Poor low end response...

[decooney]

Dirk,
Before you choose your Cobra, I recall your NorCal Cobras breakfast visit in Rocklin and us talking about this very topic of differential gear ratios, transmission choices, and what you were going to do manual vs. automatic transmission. As I recall, we discussed the taller gearset in your differential but you were considering going with a 5-speed manual trans with a lower 1st gear - but then again you were not sure about automatics either back then.

We also discussed the WC Cobra being a bit larger, maybe even smoother, and definitely heavier than other Cobras and that was one of the factors you were looking at, and "room", as I recall.

Maybe you can answer this - perhaps there was a bit of mix and match of components that occurred later on down the line then when the car got built, thus (maybe?) keeping the tall axle ratio rear then possibly switching to a C6 automatic somwhere along the line instead of going with a lower gear 5speed manual trans? Did this possible scenario occur in the end?

I ask these questions because I went through a similar situation with a friend who HAD to go to an automatic, with a little bigger cam. He later removed the torque converter and went with a 3,000 rpm stall speed. It definitely helped but it was not "snappy" with the low end grunt he was looking for either. After him trying various things he went back to a manual and with a lower first gear was able to get the extra little low-end grunt he needed and sold the car because he hated to shift. You give away something on both sides of the equation I guess.

Based on what cam/axle ratio/trans specs you've noted here, (Unless you go with a Richmond 5speed say with a low 1st gear and) I'd pitch the tall gearset (If you keep the automatic trans) in the rear and go to at least a 3.25 rear axle ratio (with posi) and try that first. I recall you wanted something you could still drive on the freeway; with the automatic the 3.25s are not bad and with a bigger cam it works out okay. It won't be a rocket ship off the line with the heavier Cobra weight there, but it should do better than it is now that's for sure. I don't work on other peoples cars, but you might consider bringing it to a friend I can refer you close by to where we do some project collaboration together. He does a lot of Cobras and troubleshooting and reconfigurations... particularly in this area we are talking about here.

Then, if you still absolutely must keep the automatic trans, you could look into what someone else suggested with a higher stall speed with your converter but I'm not sure you'll be happy with that either - gets a little sloppy and irritating at times zinging the motor up a bit before you take off. Maybe first decide if you must keep the automatic or not, then start making other changes. If you are not sure what to do about keeping the auto trans or going with manual trans, and decide to go manual, you can come up here and we can send you to a local shop here in Sac. Gary works on Graydon's West Coast Cobra and has it setup nicely for him to shift, custom hydraulic setup (basic) and it works well. Perhaps I can hook you up with Graydon E. and he can share with you how his car West Coast Cobra runs/shifts. We've gone through all the same exact discussions on his car, numerous times. Let me know and I can have him call you. DC