Weber 38 Carb

[Jim Gustafson]

Does anyone here have info or feedback regarding the 38? I'm curious to know what jets and emulsion tubes were found to work well?
(uprated cam, iron head). You can pm me if you prefer.

Thanks,
Jim Gustafson

[BeerBudgetRacing]

I'm expecting mine from Ivey this week. Running ButtonWillow next weekend.

It all depends on if jay works this weekend!

[T540]

Idle jets: 60
Mains:185
Air Correctors:190
Emulsion tubes: F50.

PM sent with details.

[DK540]

Also curious about your tweaking and results. I really enjoy my 38/38 on my MGB vs the old 32/36 (that's what was in the car when I bought it).

I will compare the jetting noted with mine, though it is obviously not a high rev race engine. I would be interested in the document that was pm'd if you don't mind sending it.

Thanks!
David

[T540]

PM sent.

[Jnovak]

I sure hope that these new changes help the Pinto performance. I wonder how many Pinto powered FC cars are sitting out?

[T540]

For those of you interested in the details here it is.

I have a new 38 DGMS (Manual choke) carb on my Pinto.

The carb has the choke removed and the power valve disabled.

It also has a second vacuum operated accelerator pump or low vacuum enrichment pump, I'm not sure which it is, but I disconnected the vacuum lines and blanked the ports off. This pump looks like the mechanicaly operated accelerator pump but sits on the other side of the float bowl.

Float level is set to have the fuel at "top of the beach" + 1mm. When I set the float level as per the weber manual by holding the top cover so that the float just touched the needle valve it resulted in a high fuel level and the main circuit starting to deliver fuel at idle with an erratic idle so I adjusted it down by trial and error.

Both throttle plates are geared to open simultaneously.

The emulsion tubes are the factory standard F50.

Idle jets: 60
Mains:185
Air Correctors:190

Fuel is 70% Avgas mixed with 30% 98 octane unleaded pump gas.

Running at Sea level plus maybe 150 feet (Perth, Australia)

[DK540]

Since I can't send photos via PM, I thought I'd share a couple of my old T540, which I rehabbed and has been sold twice, and is still racing somewhere in the Eastern U.S. I have some diagrams and old sales graphics... PM me if you want them and I can send via email.

David

[Clyde]

Here at Formula Haus we have a brand new never used Weber 38 Carb cost without shipping is $175.00 call 914-576-1916 or E-Mail ajp241@yahoo.com Carb is located in Hagerstown,MD near Summit Point Raceway in WV.

[westwood95]

I'm expecting mine from Ivey this week. Running ButtonWillow next weekend.

It all depends on if jay works this weekend!

Any update on 38/38 carbs ?

[gonda]

Thanks for the info. 540. Sorry I didn't get back to this sooner. I think I am starting to get a handle on all of this but there is still one area that I'm not to sure about. That has to do with the antisurge tubes or dump tubes as they are called. It looks as though the 38 has a similar system already built into it so that adding the tubes is unnecessary. But the system on the 38's also have very small round brass restrictor plugs in it with tiny little holes in them that are hard to see let alone measure. Have these just been left as they are or have they been made larger by drilling?

Gary

[T540]

It's been a while since I did the carbs.

I think the holes you refer to are to do with the vacuum signal for the power valve which is removed, thus they should be soldered closed.

I will open the carb up next week and take some pics and give a rundown of what I did.

The Jake Lamont FF book gives a good description of how to mod the carb.

I did not however fit dump tubes.

[gonda]

I'm fairly sure that they are not the vacuum signal for the power valve. If you follow them down they go into the float bowl where there is an opening hole.

Also, for anyone looking for info. on the 32-36 weber the following url gives a complete description with detailed photos.

http://www.thelolaregistry.com/DIY/Weber.htm

Gary

[Rick Kirchner]

anybody have any updates to this thread?