Stumble when accelerating

[CashMoneyKC]

If your manifold vacuum is too low the bypass valve will remain closed causing drivability problems and high IAT's. Or sometimes you have just enough vacuum to open the valve but as soon as you touch the throttle the valve closes or flutters open/closed. I had my car tuned by 2 tuners with the stage 4 cams and it never drove well. It always wanted to stumble or buck when taking off and also stumbled when transitioning from vacuum to boost. I couldn't drive in city traffic for very long before IAT2's would reach 80C/180F due to reversion. I think a good local tuner could have resolved the driving issues but I don't have access to one so I swapped to some milder cams.

Did it all work out for you? I’m nervous about getting a cobra with cams.

 

[olympic]

Did it all work out for you? I’m nervous about getting a cobra with cams.

I swapped out the 236/244 duration Stage 4's for some 222/222 duration Sage 2's degree'd to Crower specs and then had it tuned by Kevin Dunn. Now it drives perfect but the choppy idle nearly is gone. It was a trade I was willing to make though as I hated driving it with the big cams.

I think with proper degreeing and a good hands-on tuner you could get a cammed car running and driving very well but I just didn't have those resources available.