Necessary to retune?
Thread Starter
Teching In
Joined: Jan 2010
Posts: 36
Likes: 0
Necessary to retune? I had a heads/cam LS3 that was tuned on the dyno. I just replaced the engine with another heads/cam LS3 using the same heads/cam setup. All the parts on the new engine are identical to the old engine (same parts, but different physical parts), except for the fuel rails. Do you think it's necessary to retune the car given the new parts, while identical to the old parts, may have slightly different tolerances/etc., or would you think my original tune is close enough?
TECH Fanatic
Joined: Oct 2014
Posts: 1,220
Likes: 179
From: Virginia
Open or closed loop tune is the consideration here. If you have a standard closed loop tune, then you should be fine, MAF and trims will adjust and make up for the difference. If however, you are running a open loop set up, then yes, you should definitely tune it. That's pretty much a manual fueling method, unless it's set up with STFT's on, which is possible.
Anyway, if the factory can get away with one tune for thousands of vehicles, then you should be alright. This also implies that you are running the SAME sensors too, MAF, MAP, and O2's, in their original locations when tune was done. If not, well....
Anyway, if the factory can get away with one tune for thousands of vehicles, then you should be alright. This also implies that you are running the SAME sensors too, MAF, MAP, and O2's, in their original locations when tune was done. If not, well....
