Why more lag now?

[jvest]

Last week I pulled my cab to replaced the headgaskets and install studs. During this project I did all the standard upgrades as well as adding 155/30% injectors and 4" turbo back exhaust. I also had my tunes tweeked for the injectors. (Looney has been my daily driver tune for several years.) After this work I've got a lot more turbo lag. I've checked the vgt plug and I had cleaned the turbo about 25,000 miles ago as well as giving it a couple of WOT every week to keep the guidevanes working properly. Any suggestions why I've got more lag after this project? Could it be the large exhaust?

Thanks,
Jim

[southend]

Check for exhaust leaks, seems this gets posted often.

Sent from my phone that somebody didn't help me get.

[gsracing38]

It may be a long shot but what you are feeling might not be lag. I did studs on one and the gas pedal got out of calibration which delayed input from the throttle to the engine. To reset, just turn the key on, slowly press the pedal to the floor and then slowly release it. Turn the key back off and your done. This may be way out in left field but its worth a try since its quick and free.

[jvest]

Thanks guys. When I get home tonight I'll look for a possible exhaust leak around the manifolds and pipes feeding the turbo. I put new gaskets, cleaned the manifolds and torqued the bolts. Any recommendations on finding a small leak in this area other than listening and looking for soot?

I'll try the recalibrate procedure at lunch today and see what that does.

Thanks for the help,
Jim

[jvest]

Well I didn't see any exhaust leaks, but I did the the recalibrate on the pedal and it seems to have resolved this issue. Thanks for the help.

Jim

[gsracing38]

Awesome, glad to help.