Stop in for a cup of coffee

Mopar Tim said

So have a question, why does engine idle faster after x pipe install, BUT drop more RPM when put in gear?? Nothing else changed. B4 x pipe, it would idle at about 1200 RPM in gear, real nice running here. NOW it idles 1000 in gear and the more I turn up curb idle, the harder it engages into gear. BUT still stays at 1000 rpm?

Click to expand...

Exhaust Scavenging efficiency.

The x-pipe evens out the flow between cylinder banks resulting in more power at low RPM (higher RPM in neutral) but also adds more power in gear so that torque converter slip becomes less and pushes the in-gear RPM down because it is adding more power...fighting against the stall limit.

You need a 3500 stall converter for that cam and engine now that you have let loose the low end power. I had the same problem on my 360 magnum and the 2500 stall couldn't handle the power. So I either had to drop the cam down or bump up the stall.

I chose to drop the cam down since I wanted a cruiser not a track beast.