Just finished putting my truck back together after cam swap, oil pump, ls2 timing chain, 7.4 hardened push rods by comp and jegs brand roller rockers (would have went with harland sharp rockers but the back of the rockers were touching the head, tech told me to take them to a belt sander, I sent them back and bought the jegs brand, real nice set). Went to start truck last night, started fine, ticking went away after lifters pumped up with oil, everything was running fine till I tapped the gas and now I can't keep it idling unless I press the pedal and hold it at 1000rpms. Engine sounds fine, stinks of fuel (like it is running rich), I did recharge the air filter?? Old cam specs are

2001 LS6 cam
207/217 int/exh @ 0.05" duration
0.525" / 0.525" int/exh lift
116 LSA

New cam specs are
lunati
216/224 @ 0.05" duration
0.558" / 0.560 int/exh lift
112 LSA

Anyone have an idea? I know I am going to have to get it retuned, someone did say I should drill the hole in the center of the throttle body bigger till it idles fine, but no bigger than 1/4. Thanks

 

I was just reading that in another thread myself, makes a lot of sense, if your not comfortable drilling you can get a throttle body blade out of an older vortec it has a bigger whole i believe

 

or just wait till its tuned..

it doenst take much to get it to idle right..
i went from stock to a 215/215 .566/.566 114+4 and it cranked and idled fine.. it was really rich but it ran...
after leaning out idle and messing with some other stuff it got alot better.

 

+1 it needs tuned.

When I swapped my 216/220 in it would idle fine and die at times in gear or if i slowed down too fast. Once it got tuned it ran fine.
That's all part of the swap. the computer is feeding fuel for the old cam and the new cam is trying to dump more in.
tune it

 

You need a retune for sure... I wouldn't worry

 

pull the vac line on ur driver side valve cover in the back, that will help it...TRUST ME!!!!!!!!!!!!!!

 

well on DBW trucks anyways

 

How would pulling the PVC line on the drivers side help it to run better? It seems to be running rich now. Also, I spoke with my tuning guy a little bit ago and he agrees with you guys on the computer feeding the fuel based on the older cam. Definitely +1 for the retune, to bad I have to wait another 2 weeks for him to come over. Thanks for all your help guys. At least I got the o-ring put on right for the new oil pump, that was my biggest worry. Truck is putting out around 72lbs at idle with cas gtx 10w-30 for break in, then debating on synthetic royal purple, since I only put about 1500 miles on the truck yearly.

 

dunno, but it worked when i did my cam swap

 

I think I am going to give it a try tomoro. My buddy is coming over after work and we are going to try and take it out for a drive to see if the computer will relearn itself somewhat. As for now, I am done f*****g with it