I am currently running a 355ci turbo LT1 with AFR 210cc heads, that has seen over 20psi. I am having a bit of a slight hesitation/ breakup problem when cruising. If I let off the gas, as I would to shift, then get back into it with ease or to the floor the car begins to stumble and jerk violently. I clutch in and blip the gas to a higher RPM and it stops. Data logging revels sudden changes in MAP pressure that cause a goofy A/f mix. I have replaced the MAP sensor and gasket in the intake manifold and checked all vacume ports. Immediatly after the new MAP sensor the problem seemed to fade, only to return again. Any thoughts on this issue? This only happens out of boost, as soon as it spools it pulls hard and clean. Basically its just when I am tooling around town but I will happen if I try to shift fast under boost and get back into it.

 

Whats your PCV setup out of curiosity? Mind giving more detailed specs on the car and any pics?

 

are you running a maf sensor? if so where is it at?


can you post the data logging?

 

PCV is just the valve pushed into the grommet and vented to the atmosphere.

No MAF, speed density
I don't know how to post any of the logging but I think I can figure out how to email it.

 

speed density on the LT1 pcm with boost works like **** IMHO.

 

shoot it over to blkchevyz@mofbody.com

 

good thing I sold my LT1 pcm on ebay when I bought my FAST

 

how bout spark plug gap?? maybe its too big?

 

if your PCV valve is vented to atmosphere that sounds bad to me... I would try running one with a one way check valve in it to keep boost from getting into the crank case but still maintain crank vacuum off boost.

Chris

 

Log files sent to Blkchevy, I hope you get them.

Autolite 104's gapped at .032

The PCV is in the grommet just not seeing any vac. from the engine because its not hooked back to the throttle body. Is that something that I should reconnect?

 

Probably a dumb question, but did you block off the port on the TB that the PCV line hooked too?