I've been reading that alot of us are having problems with the gearbox. I too had these problems and I think have identified the problem. It seems the cables are extremely sensitive to heat. If the cable gets even a little heat, the teflon becomes "gummy". You won't even notice it because of the leverage you have using the shifter. The problem is though, the actuator spring (on the actuator at the back of the gearbox)isn't strong enough to handle the additional friction caused by the gummy cable (it seems just strong enough with a good cable) and with leverage working against it (bell crank, shifter lever) it can't return the actuator back to it's centering point where it can "re-engage" the "cog" for the next gear change. If the actuator lever is even one degree shy of it's centering spot, it won't re-engage the next "cog"
. At my first outing at Lime Rock last weekend, I gummed up my first cable and the crew at Cape Motorsports lent me their spare cable (they were testing a higher heat resilient cable and had their stock one in the trailer). It too was heat shielded, but sure enough, after a few minutes on the track, I started having problems. The stick shift felt the same but when I detached both ends of the cable, I discovered it was considerably harder to push/ pull than before. There was no evidence of any extreme heat on the silicone/fiberglass heat shield and I routed it as far from the headers as slack would allow. The guys at Cape (I would also like to thank them again for allowing me to use (and ruin) their cable) believe that the prototype may not have this problem because of the large hole in the prototype's body work (for the temporary intake)
may have released enough heat to prevent the cable from getting "gummy". There seems to be alot of guys trying different things. I purchased a cable 24" longer and routed it down the left side of the car. There are obviously a few bends but the additional friction seems negligible. I also spring loaded each end of the cable to assist the actuator's spring to return the actuator lever back to it's centering position.
I'll let you know how it works this weekend.
Also, my car's steering shaft was too long, creating an angle too extreme in the upper universal. I ended up cutting and welding the shafts to make them work. Check your universals and make sure they're at 180' to each other (like a driveshaft), mine were aligned which made the problem even worse (the car was undriveable).
I also mounted a battery behind the seat, and don't forget to screen the radiators.
I only had two real sessions in the car once some bugs were resolved, and other than the shifting difficulties, the car was a complete blast to drive and remarkably similar to my 92 Van Diemen (understeer and all) except that torque and throttle response. Great motor!
Scott Brickey
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