I had my 241s ported and my ls6 intake ported as well. Car has a 228 comp cam. Got the car out back together let the the gaskets seal etc. temp stays good! Just at woot my car does fine once let off my cars rpms drop down to 500. Which is not normal I don't think. I haven't gotten the car tuned yet just been driving it a little to make sure it's back up on it ls feet completely before taking it out of town for tuning and dyno pulls. It's been running off of 110 mixed with 93 and the car is not tuned for 110. No codes are being thrown no misfireing says the computer. So I'm kinda at a dead end and not sure what to think. Any opinions will be helpful thanks!

 

If you have yet to tune the car with the mods you listed, than that is more than likely your issue.

 

+1

Everything you described is cammed but untuned behavior