View Full Version : 2002 engine recalibration
BluavalancheZ71
09-04-2006, 11:21 PM
I currently own a 2002 Chevy trailblazer. A co-worked pick up an 2006, I noticed that the new TBs with the 4.2L now have 291 horsepower mine has 275 (stock numbers). does anyone know is this just a reflash of the PCM to get this or did they do a new cam grind or other modifications to the newer 4.2Ls? Just wanted to see if anyond does know. Also I do have access to the updated gm scan tools :D
Later
Blu
ehall0527
09-04-2006, 11:28 PM
I'm pretty sure those gains where acheived by adding a MAF sensor. Someone will correct me if this is wrong.
Trailblazin
09-05-2006, 05:38 AM
- Slightly higher compression ratio
- Improved intake
- Added Maf
- Different tuning (not that much extra though)
MTPockets
09-05-2006, 05:53 AM
Lots of posts on the 2006 4.2L upgrades. Basically she's got a new cylinder head along with what ehall and trailblazin said.
Joel
blandmiller
09-05-2006, 09:05 AM
One more very insignificant change:p , larger valves....
So gurus,
what are the easy upgrades of the forementioned, so that we could increase the HP with old engines...
If you want to boost your '02 up to the hp levels of the newer 2006/2007 models, but with improved throttle response and tranny shifting, your best bet is a PCM tune. Lyndon at Wester's estimates a minimum gain of 10%, which would put your '02 at 297 hp or better with just the tune. Other easy items that help, would be an intake and exhaust system or replacing the main muffler with a high-flow unit.
blandmiller
09-05-2006, 01:00 PM
While you are at it, get your hands on the high flow head. I will buy it if you don't.