SEB/MAC Asking for C Modified Feedback

[racerjon1]

Brad put this in the "Hoosier" thread, (thank you Brad) but since it isn't Hoosier-specific, I wanted to create a place to discuss the specific feedback the SEB/MAC is asking for, RE: C Modified Formula F Cars.

Official letter info! See latest FasTrack -
"#34411 Tire shortages in CModWith the uncertainty of current tire availability, the MAC and SEB are looking for feedback on the possibility of moving CM from its current Hoosier tire to a specified radial tire, beginning for the 2025 season using either the Toyo R888 (used in the Canadian F1600 series) or the Yokohama A048 (used in Australia and New Zealand Formula Ford series). Moving to this tire would keep existing wheels and open up availability of tires to the class, while decreasing running costs."

Lots of this was done before more data has rolled in but this is the letter you should reference from now on with your thoughts. Let's recap:

Hoosier has made one more run of the rear tires. There is no guarantee that another run will be made.

We have 2 working options available:
1) keep the same wheels and decide on a spec radial tire
2) allow different wheel sizes and any tire can be run

pros/cons (from my point of view)
1) pros - spec tires. car prep and driver talent determine winners. cheaper operating costs. no new required equipment.
1) cons - less total grip, everyone has to move to a new tire so burn up takeoffs between now and 2025. (no older tires for first season of spec tire requirement)

2) pros - real race tire grip! can balance wheel/tire to particular driving style. unlimited tire choice.
2) cons - those who can find/afford wheels will have an advantage. Specific tires for temp/conditions will have advantage so multiple compounds in the trailer for truly pointy end competition.


So please please please write in with your thoughts. Let us know if you like the spec tire option or the open wheel sizes option.

Brad.

[-pru-]

Thanks Jon; long term, a separate thread is the right move...

To that end, my comments from the previous thread:

Thanks Brad; appreciate the efforts to keep the CM/FF tire discussion moving forward! Glad to hear that this is slated for 2025; that is, plenty of time to work through comments, questions, and concerns...

One comment; include the (bias) Hoosier Club Ford R60 as a possible spec tire option. Pro; same size - no wheel, ride height, nor alignment changes. Con; needs heat to reach full potential (i.e. blankets / co-driver needed for optimal performance).

After initially being in the "FC 6"/8" wheel" camp, I've reconsidered and believe the (bias) Hoosier Club Ford R60 to be the "least painful" path forward...

[racerjon1]

And, I'll start with a couple of my own observations based on this post. My adjustments/notes are in blue.

We have 2 working options available:

1) keep the same wheels and decide on a spec radial tire

1b) We could open up a range of approved tires. While one would end up "spec" because of performance, I don't think we should limit ourselves to a single tire because there are other (lesser) tires than a full slick, including bias ply. The Hoosier and Dunlop Vintage tire come to mind. Sure, an 888R or A048 would be the best and we could even Spec it for National events, but ultimately the most amount of participation should be favored.

This is similar to how other F1600 series handle multiple tires of similar (or available but reduced) performance range handle it.

2) allow different wheel sizes and any tire can be run


pros/cons (from Brad's point of view)

1) pros - spec tires. car prep and driver talent determine winners. cheaper operating costs. no new required equipment.

• As issues companies continuing to make decisions based on market share continue to arise, aligning with a common F1600 tire elsewhere creates a "safety in numbers" factor. We don't have enough numbers for Hoosier to make the R20, who is to say that's not the R60 down the line? I reached out to Toyo and their first question about longevity/production was "how many tires do you think will be purchased?" Aligning with the (more popular) vintage or street-tire Road Racing classes helps reduce this possibility.
• Dry tire = rain tire. It's not just about cost, but operating and equipment complication as well.

1) cons - less total grip, everyone has to move to a new tire so burn up takeoffs between now and 2025. (no older tires for first season of spec tire requirement.)

1) Complications - We need to consider what a change in tire performance will do for the other cars in C Modified. I'm not convinced that a Solo Vee will be faster (so it might actually make MORE competition) but it must be considered as to the decision that's made.

2) pros - real race tire grip! can balance wheel/tire to particular driving style. unlimited tire choice.

• C Modified might speed up enough that we can consolidate with F Mod and have class reduction/more competition. This can lead to consolidation of B-Modified = Formula Cars/Sports Racers with wings class and C-Modified ends up formula cars and sports racers without wings class.

2) cons - those who can find/afford wheels will have an advantage. Specific tires for temp/conditions will have advantage so multiple compounds in the trailer for truly pointy end competition.

2) Complications - We creep toward a "solo FF" spec like Formula (Solo) Vee. FF wheel sizes (and hence brakes, and lots of other items) have been one of the most stable rules in all of motorsports. This is more than just a "slippery slope" of rules creep, but it's a disruption of a consistent part of a system. I don't know the specific answers to this, but does it potentially create advantages for newer chassis, newer gearboxes, etc. Right now, the 5.5" wheel and a street-type (or floppy bias ply) tire fits in a "known performance" range of thousands of F1600s across the world - disruption of that for the 30-40 of us is absolutely a complication.

I think that for this thread/letters - we don't have to pick the tire we use. The real first question is:

1) Does a spec (or approved list) of tires make sense for the class?

2) In order to keep grip levels similar to what we have had available, is opening up wheel sizes for FF/F1600 make sense for the class?

Once that's decided, then we know if we need to pick a specific tire(s) and then what tire(s) to pick if so.

- Jon

[racerjon1]

As I re-read my own post, it occurs there is still another option.

Do nothing, end up trying to squeeze FC tires on FF wheels, or work the R60 as best we can, or maybe Avon makes tires. It does sound like the MAC doesn't see this as a direction - Brad, any insight here?

- Jon

[CM/FFdriver]

As I re-read my own post, it occurs there is still another option.

Do nothing, end up trying to squeeze FC tires on FF wheels, or work the R60 as best we can, or maybe Avon makes tires. It does sound like the MAC doesn't see this as a direction - Brad, any insight here?

- Jon

Hello Jon,

I have done this and even though I could drive on the R20 FC tire on the rear with 5.5 rims, the tire started to tear itself away from the carcass. I bought FC tires to see if I could see if would work. They fit on the 5.5 FF rim and looked pretty good standing still, I then went to an autocross event at Crows Landing, the day was 75 Degrees the course was 68 sec.
Did the first 3 laps on the FC tires on 5.5 rims and did a good time, the people that were helping me with advice and then to help change the tires over to the R60 compound, So in 2 laps I was faster then the FC R20. So for Sunday I left the R60 on the car.

Ben

[racerjon1]

Hello Jon,

I have done this and even though I could drive on the R20 FC tire on the rear with 5.5 rims, the tire started to tear itself away from the carcass. I bought FC tires to see if I could see if would work. They fit on the 5.5 FF rim and looked pretty good standing still, I then went to an autocross event at Crows Landing, the day was 75 Degrees the course was 68 sec.
Did the first 3 laps on the FC tires on 5.5 rims and did a good time, the people that were helping me with advice and then to help change the tires over to the R60 compound, So in 2 laps I was faster then the FC R20. So for Sunday I left the R60 on the car.

Ben

Thanks for the info Ben, and yeah, that's all the more reason that I want to know if the MAC talked about "leaving things alone" because if the R60 is faster than the FC tire squeezed, then we all just go to that. (Other than those of us who save the R20s they just bought.. or the bagged set of R35s I have..)

My point being, "staying as we are" still feels like an option, and I just wondered about it not being presented as such.

- Jon

[Jim Garry]

My point being, "staying as we are" still feels like an option, and I just wondered about it not being presented as such.

- Jon

Jon, did Ben's response sway your thinking? Or do you still feel that "no action" is a viable option?

Thanks,

[Jim Garry]

I would like to repeat the statement made to me by Adam Batton, Hoosier's Circuit Racing Business Unit Manager. He said:
"I personally think a radial street tire will be too stiff, heavy, and not compliant enough to warm up the tread compound to an acceptable level in a solo/autocross application for a CM. The weight and geometry of these cars favor a bias ply construction."

[racerjon1]

Jon, did Ben's response sway your thinking? Or do you still feel that "no action" is a viable option?

Thanks,

Right or wrong, "no change" could still be an option. It's not one I favor, but it's an option nonetheless.

unless... the MAC/SEB has decided that we're either going to a spec tire or wheel change and, "no change" has been ruled out.


Think of it like poll options...

1) No wheel change, run whatever the best tire available is.
2) No wheel change, reset tire rules to a spec tire.
3) No wheel change, reset tire rules to a set of approved models.
4) Wheel change, run whatever the best tire is.

Are they all on the table, or has the MAC/SEB actually ruled out #1? That's all I'm asking.

- Jon

[Lynn]

5) Wheel change, spec Hoosier FC bias plies.

[Jim Garry]

Right or wrong, "no change" could still be an option. It's not one I favor, but it's an option nonetheless.

unless... the MAC/SEB has decided that we're either going to a spec tire or wheel change and, "no change" has been ruled out.


Think of it like poll options...

1) No wheel change, run whatever the best tire available is.
2) No wheel change, reset tire rules to a spec tire.
3) No wheel change, reset tire rules to a set of approved models.
4) Wheel change, run whatever the best tire is.

Are they all on the table, or has the MAC/SEB actually ruled out #1? That's all I'm asking.

- Jon

Nothing has been ruled in or out Jon. This initial proposal of spec tires is just the first and perhaps easiest proposal for us to offer our responses.

[Jim Garry]

For any of the CModders that favor spec tires, would you consider purchasing a set and testing them? I would donate to the cause.

[Jim Garry]

It's been pointed out in other posts on ApexSpeed (I think) and over on the Modified page on FaceBook but is worth repeating here.

To use the street radials there will have to be changes made to suspension. When road racers changed over to the Hoosier radial now being used by SCCA Formula F cars some cars were able to adapt with less difficulty than others. There are threads to look for here on ApexSpeed. Certainly there has to be an ability to dial in a LOT more camber. On some cars that presents a great deal of difficulty and requires involved modifications to the suspension. Also many cars needed roll center changes.

Gearing may change, I don't know if the street radials are lower or taller. If taller, most of us are already geared as low as we can go so a taller tire will just mean a slower getaway from the start line.

[racerjon1]

5) Wheel change, spec Hoosier FC bias plies.

I thought about putting this down.. I see I should have!

[racerjon1]

To use the street radials there will have to be changes made to suspension. When road racers changed over to the Hoosier radial now being used by SCCA Formula F cars some cars were able to adapt with less difficulty than others. There are threads to look for here on ApexSpeed. Certainly there has to be an ability to dial in a LOT more camber. On some cars that presents a great deal of difficulty and requires involved modifications to the suspension. Also many cars needed roll center changes.

As one of those guys (my DB3 physically can't get the camber those spec radials want) this one hits close to home. The good news - from what I can tell so far - is that it's not all radials but the Hoosier radial specifically that loves the camber.

I spoke with a Miata racer about this, and he asked, "won't the cars with radials still need the camber?" and When I told him that I'm not hearing the same issues with the need for Camber out of Canada (888R) or Australia (A048) he had a "lightbulb" moment.

He said, "Oh, so it's like the Spec Miata Hoosier, they jsut seem to want tons of camber. The Spec Miatas have wheel bearing issues on the spec Hoosier now because of all the camber they need."

I've searched threads in here, and it seems that the 888s in Canada don't seem to require the same camber. I've also watched the video of the aussies running on the A048, and there seems to be a wide range of cars competing so that leads me to believe it's also not the case there. I'll go ask...

Gearing may change, I don't know if the street radials are lower or taller. If taller, most of us are already geared as low as we can go so a taller tire will just mean a slower getaway from the start line.

I suppose I should just share my spreadsheet:
https://docs.google.com/spreadsheets...5hY/edit#gid=0

That has all the diameters and such for each of the "popular" FF tires. The range of tire diameters is 22.5 to 22.7 for each of these. The A048 is the 22.5 and the Hoosier Vintage, SCCA Spec Radial and Toyo 888R are 22.7 and the cantilevered bias ply is 22.6. (Links to my source data are in the sheet.)

- Jon

[chrisw52]

I think Racerjon1 and I are in agreement here.

https://www.apexspeed.com/forums/showthread.php?95941-News-From-Hoosier-Re-C-Mod-Tires&p=653473&viewfull=1#post653473

from the other thread on this issue:

I second that, but also we need to open up the tires I think. With an open selection on rims and tires, we can figure out as competitors which tires and rims work best for our individual cars. And remember in autocross we already do this by allowing plus sizing on rims and tires in the stock classes.


I am encouraged by Jim's comments on the testing of the 888R tire. That said I am still on the fence about which direction we should go. If we go with these new spec radials, that will be the most expensive solution for the competitors with older cars. I would have to rebuild the lower control arms on my old 91 euroswift at a minimum to get the required camber adjustments. With my new car, an RF98 I am ok with radials. The last thing we all want would be to adversely affect the older cars.

I am somewhat against the idea of a spec tire. We had a spec tire for the class (hoosiers) and look where that got us.... If we want this class to continue we need more flexibility to choose the tires available as we move forward or we risk these types of tire shortages to continue.


I would propose that we setup the next couple seasons as a "Open test" to find a longer term solution to this tire problem. So what I would propose is something like this

1. season one - open wheels, open tires gather as much test data from as many drivers as possible.
2. season two - we should know which tire rim combos are working by this point, size the available wheel/tire options accordingly.
3. season three - consensus for a spec tire (with a long term availability)?

I think this is a reasonable solution because we let the competitors figure out what tire/rim combo will work, it gives the SCCA some breathing room to design a better rule to accommodate the changes in the tire marketplace. And third, it gives us the chance to make a decision based on hard evidence, not hypothetical solutions.

[Jim Garry]

This sounds OK but how do we deal with legality while competing at Tours and the National Championship?

[Lynn]

It just occurred to me that if we go to 6 and 8 inch wheels, I can use the same tires on the Reynard that I use on the SoloVee.

Although the SoloVee uses 8 and 10 inch wheels.

[racerjon1]

I think Racerjon1 and I are in agreement here.

https://www.apexspeed.com/forums/showthread.php?95941-News-From-Hoosier-Re-C-Mod-Tires&p=653473&viewfull=1#post653473

from the other thread on this issue:

Just so I'm clear where I stand personally - I believe that we have what is a near-spec class with 50+ years of chassis to draw from, and we should lean into that ruleset to keep the most stable base for purchase and participation. With that in mind:

1) I absolutely, 100% do not favor changing wheel sizes. The rest of the FF's in the world run on 5.5" wheels. Any FF purchased is going to have 5.5" wheels. We all have 5.5" wheels - and we should stick to that.

2) I favor a range of specified tires (perhaps with a spec tire for national events), picked from widely-used FF tires globally. The Yoko, the Toyo, The Vintage spec bias-ply (Avon, Dunlop, Hoosier) I do not favor a tire only used by 50 or so cars - that's the issue that created the loss of the R20/R25 (E.g., the Hoosier SCCA Spec road race tire for instance.)

3) I don't consider "ultimate performance" to be a primary concern. I do consider a well-balanced tire that works on many generations of cars, and is the best economical choice within those specs to be the most important factor.

[TedV]

My thinking follows what Jon K has posted. I keep asking why people want to instantly jump to the 6 & 8" FC rims with no answer with documentation why the desire for the 6" front other than a used set of rims cost about the same as just rear rims. What about the cars that can't find used rims and have to buy new? Why should they have to buy all 4 rims? The FC front is working on the 5.5 now. It removed the push the 20x6 tire had. By going to a 6" rim from 5.5 with the 20.5x7 tire, it will increase the front grip. All tire testing in the history of tire testing says that will happen. If the desire to run 8" rears with FC tire what is the issue with leaving the fronts on 5.5 as not everyone can find used sets and the front will still be the limiting grip of the car? One would need to fine tune the car balance for the 8" FC tire. Changing the rim width and then possibly the backspace or center of contact patch offset will impact the handling balance.

Unless the ultimate goal is to combine CM and FM again, then sure, go for the 6" & 8" rim rule. But that goes against the rules package principle of FF in CM.

The CFF bias cantilever R60 is A7 compound.
The spec radial FF is A7 compound with more mass in the tread face that would need to heat up to let the compound work better along with floppy sidewalls equals lots of chassis changes for autocross. The R60 CFF bias is the winner of the 2 for me. I can not comment on why Hoosier prefers to build a radial over the bias as I signed an N.D.A. a while back. Bruce, Adam, Tim, or Jeff would need to say why.

I believe the goal is to keep the cars balanced and fun. The more everyone discusses, the more I think to leave the 5.5 rim rule and let the smoke clear with what will work. Too much speculation and not good testing giving rules change choices from perception.

I would love to see a weekend of testing report on the 5.5" front, 8" rear with the FC tires like Jon did in the other thread with the 83 Van Dieman. That is about the most rules creep towards SoloFF I could agree with. The FF cantilever rear kept getting more skinny over the years all while we were running the wide front, 7" FC front. There might be a need to go to the 6" front but I'd prefer testing results over speculation results. Or creep to that width slowly.

[Jim Garry]

No worries Jon, you have been very clear all along on your preferences.

I am willing to wait and see how further testing plays out with the street radials. But please provide comparison if possible of same or similar car on R20 tires. Obviously they will be used R20s. If they are 2 or 3 seconds off, well maybe that's OK. But beyond that, it's not reasonable IMO.


After Nationals I will consider testing a set of one or the other tires. I'll keep a look out for summer testing reports.

For now, barring future information, I maintain the most efficient and fun way forward is to open up the wheel allowance. The class performance will see the least change that way and the cars will need the least modifications (actually will only need typical simple adjustments of ride height, camber, sway bar, and maybe a simple spring change but no geometry changes).


Formula Ford has not been a static class for 50 years. There have been many changes along the way, many rules based and many technological based. Changing the wheel allowance isn't a big deal to me because based on historical changes that have occurred all along, there isn't too much that is sacrosanct. And the future rule, if we go that way, would continue to allow 5.5" wheels. In my case I would probably start out by just obtaining rear wheels.

I see a wheel change as something we would use for autocross but simply replace if the car were to be road raced. Just like the gears would have to be changed, especially our very expensive first gear. And to RR we'd all have to use the Hoosier spec tire and change a lot of things including in many cases geometry mods.

For nearly all our cars there are many other requirements in order to go RR. A fuel sampling port would have to be installed. And although my car retains its fire system, that would have to be installed for the majority of autocross cars. Harnesses in autocross cars are probably all out of date. We also use different rules for determining if roll bar height is sufficient. This might require some expensive changes if a car were to be raced vs autocrossed. All of these, of course, are not performance related but are items that represent differences between AutoX and RR.


Regarding a comment in the previous post: " I favor a range of specified tires (perhaps with a spec tire for national events), picked from widely-used FF tires globally. The Yoko, the Toyo, The Vintage spec bias-ply (Avon, Dunlop, Hoosier) I do not favor a tire only used by 50 or so cars - that's the issue that created the loss of the R20/R25 (E.g., the Hoosier SCCA Spec road race tire for instance.)"

Which tire would that be other than the present R20 cantilever?

Finally, if Hoosier were to relent and agree to produce 50 pair every other year would that be viewed positively by you?

Enjoying the back and forth of this discussion.

[Jim Garry]

Regarding Ted's post above, I have no issue with just allowing the rear wheel change. Others were very vociferous in their objection to just the rear change. But I don't see it. However if going to the 6" fronts is what it will take to get the change in wheels at the rear, I'll go along with it. But preference is just rears. If I ended up buying used wheels in a full set, I have a feeling I could sell the fronts-only to a road racer.

[chrisw52]

This sounds OK but how do we deal with legality while competing at Tours and the National Championship?

There are only limited know number of tires that will fit the rims, so just use those...

[evildky]

I'm fairly new to the FF's compared to most of you guys, Got my car in 2017 I think. When I got the car the tires weren't cheap, but they were cheaper than tires for my fendered cars. That is no longer the case. Price point and tire life are factors that will determine if I run the FF or a fendered car. Perhaps I'm alone in this but $1650 for tires that are good for a year or less on a car I cant use for any other discipline makes me want to park the car again.

That being said, what about running the front size on the rear? I realize this might not be ideal and may require dialing in the car all over again but I'm just wondering if this is any more or less trouble than some of these other options being discussed.

Forgive my ignorance of this is a horrible idea

[TedV]

That being said, what about running the front size on the rear? I realize this might not be ideal and may require dialing in the car all over again but I'm just wondering if this is any more or less trouble than some of these other options being discussed.

Forgive my ignorance of this is a horrible idea

Contact patch is shorter and ultimately smaller with the front tire compared to the rear tire. It might heat up and fire faster than the full size rear with a question if that would make for as much grip? Also the shorter tire radius would reduce rear ride height making for a need to change pick up points on the chassis to keep the relative geometry with a change to spring rates also. Lots of work. It has been done road racing for a Road America setup. It allowed for higher straight line speed, giving up a little in corners but overall was faster lap time. The higher straight speed is why the cantilever rear got narrower with an altered shoulder profile over the years of development Autocross has few straights with more emphasis on ultimate grip, transition response. Unless you like to experiment, probably not a wise choice for autoX

[racerjon1]

Also enjoying the healthy discussion on directions forward for the class. Ultimately, whatever each of our specific preferences, I am confident all of our final goals are focused on, "a better and healthier C-Modified."

First up, I want to talk about the road race to Solo Conversion - seeing as how I'm a participant in both.

For nearly all our cars there are many other requirements in order to go RR.

Yes there are things that are needed, but if you compare it to say - a Street Class car or even another Modified class car - CM Formula F is the absolute closest to a turnkey road race car as a vehicle than any other in SCCA Solo.

In addition, the crossover is not as much about making a Solo car a road race car as vice-versa. An older, non-competitive (or driver who finds themselves with less desire/resources) with a Road Racing Formula F can essentially take that car (or sell it) and it's ready to go autocrossing. C Modified benefits from hand-me-down road race cars, and this is the more important part IMO.

Regarding a comment in the previous post: " I favor a range of specified tires (perhaps with a spec tire for national events), picked from widely-used FF tires globally. The Yoko, the Toyo, The Vintage spec bias-ply (Avon, Dunlop, Hoosier) I do not favor a tire only used by 50 or so cars - that's the issue that created the loss of the R20/R25 (E.g., the Hoosier SCCA Spec road race tire for instance.)"

Which tire would that be other than the present R20 cantilever?

Here is a list of tires run as Spec (or approved) tires for Formula Ford/1600 in many US series, and elsewhere in the world:

Vintage Syle - Run World Wide (Treaded):

• Hoosier Vintage (Bias Ply) Front: 135/545-13 (44165) Rear: 165/580-13 (44170) (https://www.hoosiertire.com/assets/Circuit53.pdf)
• Dunlop Vintage (Bias Ply) (These seem to have disappeared from the catalog I found them in, so they may be NLA.)
• Avon Vintage ACB9 (Bias Ply) Front 5.0/22-13 Rear: 6.0/22-13 (https://www.avontyres.com/en-gb/tyres/acb9)

Contemporary Style - Run World Wide (Treaded)

• Avon ACB10 A29 Sport (Bias Ply) Front: 185/50-13 Rear: 215/50-13 The A29 (hard) compound seems to be missing from the catalog page, but there is an A24 Medium - not sure what the FF series using the A29 compound will do, but wanted to list it. (https://www.avontyres.com/en-gb/tyres/acb10-sport)
• Toyo 888R (Radial) Front: 185/60-13 Rear: 205/60-13 (https://www.tirerack.com/tires/toyo-proxes-r888r)
• Yokohama A048 (Radial) Front: 185/60-13 Rear: 205/60-13 This tire is hard to find data on as it's a specific FF tire and doesn't appear in many normal A048 retailers. (Aus FF spec tire announcement: https://docs.wixstatic.com/ugd/46d8f...5646db9801.pdf)

Racing Slicks (Only Run in The US)

• Hoosier R60 (Bias Ply Cantilevered) We all know this size! The only place such a tire is run on FF (that I can find) is here in the US in Club Ford. This size and style just isn't used elsewhere. (https://www.hoosiertire.com/assets/Circuit53.pdf)
• Hoosier R60 (Radial) This is the SCCA (and US Pro series) spec tire. These are the only places in the world (that I can find) a radial slick is run on FF. (https://www.hoosiertire.com/assets/Circuit53.pdf)

When I talk about running a range - I would not favor a pure spec tire for FF cars in C-Modified (outside of Nationals). I'd spec a list chosen from these tires with one of them designated as the "top" of the list in desired performance - that way the most amount of crossover could happen. E.g., if we picked the Yokohama, we could allow any of the tires "below" it, but not above it.

Finally, if Hoosier were to relent and agree to produce 50 pair every other year would that be viewed positively by you?

So - admittedly, I don't view it as positive.

That's still a $1,350 (not including shipping, mounting, balancing) set of tires which has a very limited useful life. Even amortizing them over a lifespan of 100 runs, which we know is questionable, that's $13/run.

I believe that we should consistently be looking for ways to reduce that cost - because lower costs will absolutely drive up participation. Sure - we can talk about the "fun" factor of slicks and perhaps reducing that "fun" might have a negative effect on some participants, but when you look at Formula F the world over - the vast amount of participation doesn't seem to mind "lesser" tires.

So - no considering the cost, I don't believe it would be positive. In fact, I think that we've been done a favor by the R20/R25 being phased out. We get to break our addiction.

I believe that we should be looking at the crossover point of fun/cost/lifespan, and finding the tire that matches that. And, as a crossover road racing driver, I wish we'd do it for our wheel-to-wheel racing too.

[chrisw52]

Also enjoying the healthy discussion on directions forward for the class. Ultimately, whatever each of our specific preferences, I am confident all of our final goals are focused on, "a better and healthier C-Modified."

First up, I want to talk about the road race to Solo Conversion - seeing as how I'm a participant in both.



Yes there are things that are needed, but if you compare it to say - a Street Class car or even another Modified class car - CM Formula F is the absolute closest to a turnkey road race car as a vehicle than any other in SCCA Solo.

In addition, the crossover is not as much about making a Solo car a road race car as vice-versa. An older, non-competitive (or driver who finds themselves with less desire/resources) with a Road Racing Formula F can essentially take that car (or sell it) and it's ready to go autocrossing. C Modified benefits from hand-me-down road race cars, and this is the more important part IMO.




Here is a list of tires run as Spec (or approved) tires for Formula Ford/1600 in many US series, and elsewhere in the world:

Vintage Syle - Run World Wide (Treaded):

• Hoosier Vintage (Bias Ply) Front: 135/545-13 (44165) Rear: 165/580-13 (44170) (https://www.hoosiertire.com/assets/Circuit53.pdf)
• Dunlop Vintage (Bias Ply) (These seem to have disappeared from the catalog I found them in, so they may be NLA.)
• Avon Vintage ACB9 (Bias Ply) Front 5.0/22-13 Rear: 6.0/22-13 (https://www.avontyres.com/en-gb/tyres/acb9)

Contemporary Style - Run World Wide (Treaded)

• Avon ACB10 A29 Sport (Bias Ply) Front: 185/50-13 Rear: 215/50-13 The A29 (hard) compound seems to be missing from the catalog page, but there is an A24 Medium - not sure what the FF series using the A29 compound will do, but wanted to list it. (https://www.avontyres.com/en-gb/tyres/acb10-sport)
• Toyo 888R (Radial) Front: 185/60-13 Rear: 205/60-13 (https://www.tirerack.com/tires/toyo-proxes-r888r)
• Yokohama A048 (Radial) Front: 185/60-13 Rear: 205/60-13 This tire is hard to find data on as it's a specific FF tire and doesn't appear in many normal A048 retailers. (Aus FF spec tire announcement: https://docs.wixstatic.com/ugd/46d8f...5646db9801.pdf)

Racing Slicks (Only Run in The US)

• Hoosier R60 (Bias Ply Cantilevered) We all know this size! The only place such a tire is run on FF (that I can find) is here in the US in Club Ford. This size and style just isn't used elsewhere. (https://www.hoosiertire.com/assets/Circuit53.pdf)
• Hoosier R60 (Radial) This is the SCCA (and US Pro series) spec tire. These are the only places in the world (that I can find) a radial slick is run on FF. (https://www.hoosiertire.com/assets/Circuit53.pdf)

When I talk about running a range - I would not favor a pure spec tire for FF cars in C-Modified (outside of Nationals). I'd spec a list chosen from these tires with one of them designated as the "top" of the list in desired performance - that way the most amount of crossover could happen. E.g., if we picked the Yokohama, we could allow any of the tires "below" it, but not above it.




So - admittedly, I don't view it as positive.

That's still a $1,350 (not including shipping, mounting, balancing) set of tires which has a very limited useful life. Even amortizing them over a lifespan of 100 runs, which we know is questionable, that's $13/run.

I believe that we should consistently be looking for ways to reduce that cost - because lower costs will absolutely drive up participation. Sure - we can talk about the "fun" factor of slicks and perhaps reducing that "fun" might have a negative effect on some participants, but when you look at Formula F the world over - the vast amount of participation doesn't seem to mind "lesser" tires.

So - no considering the cost, I don't believe it would be positive. In fact, I think that we've been done a favor by the R20/R25 being phased out. We get to break our addiction.

I believe that we should be looking at the crossover point of fun/cost/lifespan, and finding the tire that matches that. And, as a crossover road racing driver, I wish we'd do it for our wheel-to-wheel racing too.

Jon, remember that Avon is basically out of the picture, unless their new owner has changed their mind about shutting down the factory where all their bias ply tires are made.

Other than that, I agree with this proposal, it gives us (competitors & SCCA) time to figure out what the long term solution will be. I don't think running to a spec tire is the answer (we just got screwed because of this spec tire requirement with the 25b)

[Jim Garry]

I don't think running to a spec tire is the answer (we just got screwed because of this spec tire requirement with the 25b)

There is not and has not been a spec tire in CMod. The Hoosier is the only competitive tire but it's not a rule-book-requirement.

[evildky]

Contact patch is shorter and ultimately smaller with the front tire compared to the rear tire. It might heat up and fire faster than the full size rear with a question if that would make for as much grip? Also the shorter tire radius would reduce rear ride height making for a need to change pick up points on the chassis to keep the relative geometry with a change to spring rates also. Lots of work. It has been done road racing for a Road America setup. It allowed for higher straight line speed, giving up a little in corners but overall was faster lap time. The higher straight speed is why the cantilever rear got narrower with an altered shoulder profile over the years of development Autocross has few straights with more emphasis on ultimate grip, transition response. Unless you like to experiment, probably not a wise choice for autoX

Thanks for the reply. I understand this would be a compromise but it seems all the other options are as well.

[Jim Garry]

Jon thanks for that list of tires. Thanks for the research. My own research included the American Racer bias plys but they are also in the range of the Hoosier R60.

Currently you and I continue to disagree on the use of street radials.

And in addition to performance issues which I feel are considerable, there are questions on availability. Has anyone contacted these companies about that? Are those Yokohamas only available in Australia? Same for the Toyos in Canada? Or are they tires that are available anywhere? Can I call up a tire distributor and have them delivered to my house any time?

[Jim Garry]

I just spoke with Jeff Speer from Hoosier regarding tires for the upcoming Finger Lakes Tour (in about 4 weeks). After sorting things on that front, he told me the R20 cantilever rear continues to remain in their catalog. If the CM community continues to use them we could have a batch made up and sold through the Ver Mulm's as we did this past spring. (By the way, those tires are being manufactured next week.)

Of course if SCCA (us!) decides to move away from Hoosier R20's, those tires will cease to be.

It's interesting ... I initially ordered 10 rear tires (looking ahead to 2024 in addition to '23). Then with a day to go to deadline, suddenly a bunch of guys called in and I was asked to give up 6 of those tires. Now, with the most recent SEB statement saying new rules will be for 2025, I could really use those tires.

I think we could have gotten to 50 pair if word had gotten out sooner. There are some in this community who don't stay current.

I would hope that we could put in another order in early 2024.

[racerjon1]

And in addition to performance issues which I feel are considerable, there are questions on availability. Has anyone contacted these companies about that? Are those Yokohamas only available in Australia? Same for the Toyos in Canada? Or are they tires that are available anywhere? Can I call up a tire distributor and have them delivered to my house any time?

Toyo 888R

• Currently:
  Available in the US from Tire Rack and other retailers. They are currently waiting on the next shipment at Tire Rack, but that's normally a very available tire.It may be available at other retailers.
• Future:
  Toyo is working on a replacement for 2026ish. They did tell me it would be more of a dry-only tire, but have another tire in the works that they "would consider making in 13" if the number of tires was enough" - So unless we know it's a sped(ish) tire, even the 888 might have a limited life. That's my big worry there.

Yokohama A048:

• Currently: Available in Australia of course, but also available in Europe. Tires are $500-$600/set there, but of course $200-$350 shipping so I haven't pulled the trigger on a set yet.
• Future: My guess is that if they got declared a spec tire, or FF cars in the US were going to run on them, getting them here isn't that big of an issue. I'm not sure of long-term prospects for that design, as I haven't reached out.

[racerjon1]

Jon, remember that Avon is basically out of the picture, unless their new owner has changed their mind about shutting down the factory where all their bias ply tires are made.

Yeah - I thought I'd head about that but it's still a listed "spec" tire in some series across the world.

If it's really not available, that means that we would have to take it off our potential list, as will other series. (Which seems like it moves us towards five tires built with FF in mind globally.)

Jon thanks for that list of tires. Thanks for the research. My own research included the American Racer bias plys but they are also in the range of the Hoosier R60.

Yep, I brain-faded on that one and forgot to include it even though it was rattling around in my head. Of the FF tires I've talked to people about, it does seem to have the least enthusiasm though.

[Lynn]

The Brits are searching for and replacement for the Avons for next year.

[racerjon1]

The Brits are searching for and replacement for the Avons for next year.

So seemingly this means these are the currently available FF tires worldwide:

• Hoosier Vintage Bias Ply
• Toyo 888R Radial
• Yokohama A048 Radial
• American Racer FF 133 (I think this is Bias Ply?)
• Hoosier R60 Bias Ply
• Hoosier R60 Radial

Any others that folks know about?

- Jon

[Jim Garry]

Future: My guess is that if they got declared a spec tire, or FF cars in the US were going to run on them, getting them here isn't that big of an issue. I'm not sure of long-term prospects for that design, as I haven't reached out.

I think it is a big issue and it's too important to leave to guessing. A direct communication with the manufacturers is critical. This isn't an "if you build it they will come" kind of situation.

Given that CM is a small community (and thus represents low sales), there isn't much incentive for a manufacturer to send tires overseas. A written agreement will be necessary or an offshore company can just pull out and not ship anything regardless of their product being declared "spec".

Working with Hoosier and communicating with all owners of CM-FF cars is the way forward, IMO. Hoosier will make the tires we need if we can continue to place orders like we did a short while ago.

[Unbalanced Engineering]

I think we could have gotten to 50 pair if word had gotten out sooner. There are some in this community who don't stay current.

.

Or if the order had not been placed early by R&S.... I would have ordered at least one pair and a local guy who is considering buying my car tried to order another. Again, R&S didn't respond....

[Unbalanced Engineering]

3) I don't consider "ultimate performance" to be a primary concern. I do consider a well-balanced tire that works on many generations of cars, and is the best economical choice within those specs to be the most important factor.

I would point out that one of the reasons that some outsiders are interested in joining CM, is that the cars are so fast. This would not be the case on a street radial. Just something to factor in to everyone's thought process.

[Craig Henry]

All,

I apologize for some duplication I posted in the other thread.

My order of preference and some comments:

1) Have the class work with Hoosier on future group purchase batch runs as long as possible (at least one more time?)

2) Allow 8" rear rims so the Hoosier FC R20 tire can be utilized (keeping the current 5.5 max. FF rim width.)

Notes:

I'm glad Ted questioned the logic/need to allow the front rim width to be increased. I was beginning to think I was the only one questioning the need for the change. There is no problem with the front tire thus no need to make a front rim width change.

For what it's worth, I don't like allowing the rear rim width to increase as I'm a firm believer in the intent of CM/FF rules as original written/created. That being said, I don't see a better option available. I'm old enough to have seen FV's get bounced from class to class and then morphed (unsuccessfully) into SoloVees. Scares me to think this may be where FF's are headed. I apologize to all SoloVee lovers, but I've never been a fan.

3) Moving to a radial spec tire makes me nervous. Proper testing could change my mind but not until the data proves this would be a good choice moving forward. Also, I'm willing to contribute to tire testing.

Question: Am I correct that we are just tossing around our ideas and thoughts here on ApexSpeed and individual letters need to be sent to the SEB/MAC? Nothing counts unless it is in a formal letter...


Craig

[chrisw52]

All,

I apologize for some duplication I posted in the other thread.

My order of preference and some comments:

1) Have the class work with Hoosier on future group purchase batch runs as long as possible (at least one more time?)

2) Allow 8" rear rims so the Hoosier FC R20 tire can be utilized (keeping the current 5.5 max. FF rim width.)

Notes:

I'm glad Ted questioned the logic/need to allow the front rim width to be increased. I was beginning to think I was the only one questioning the need for the change. There is no problem with the front tire thus no need to make a front rim width change.

For what it's worth, I don't like allowing the rear rim width to increase as I'm a firm believer in the intent of CM/FF rules as original written/created. That being said, I don't see a better option available. I'm old enough to have seen FV's get bounced from class to class and then morphed (unsuccessfully) into SoloVees. Scares me to think this may be where FF's are headed. I apologize to all SoloVee lovers, but I've never been a fan.

3) Moving to a radial spec tire makes me nervous. Proper testing could change my mind but not until the data proves this would be a good choice moving forward. Also, I'm willing to contribute to tire testing.

Question: Am I correct that we are just tossing around our ideas and thoughts here on ApexSpeed and individual letters need to be sent to the SEB/MAC? Nothing counts unless it is in a formal letter...


Craig

If we are firmly intent on keeping the class within the original rules for the class, then our cars had better comply with the current GCR rules, including logbook.

That was also the intent of CM, as far as I am aware of, our cars must comply to the GCR in order to run in this class.

How many of you out there can say their car is GCR compliant with a current logbook?

I am almost there, I need to refresh my safety gear and then I can get a log book.