Looked up on Cobalt SS and Jbody but couldnt find a definitive answer anywhere.
1 What is the average PSI with a stock pulley M62 on a L61?
2 How much of a drop in PSI would you see with a header install?
3 How much of a PSI increase would you see with a tenth (.1") inch drop in M62 pulley size?
For future reference and because I am curious..
4 What is the average PSI with a stock pulley M62 on a LSJ?
5 What is the average PSI with a stock pulley MP90 on a LD9?
6 What is the average PSI from a stock LNF?
I am wondering to base what my PSI should be. Thanks guys.
PSI is a measurement or resistance.
- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs
of*
- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs
My L61 bone stock with the M62 stock pulley did about 10.5 PSI as measured by the 2.5 Bar Tmap in HP tuners.
"In Oldskool we trust"
as oedwards said, psi is relative to resistance.
for instance, my setup is making 11psi around 7k (similar the y3llowcav) but i'm running a header and full exhaust and a 3.1 pulley.
strat81 wrote:as oedwards said, psi is relative to resistance.
Truth. PSI isn't everything. People typically report lower PSI numbers after a good intercooler install but make more power. I wasn't too truthful saying bone stock I suppose. I was just thinking about internals and TB. I have a pacesetter header, hi-flow cat, and 2.5" all the way back.
"In Oldskool we trust"
I know.. Ive read and heard that everywhere. I believe it too. Although, it gives a lot of answers to the healt of an engine. But does anyone actually have averaged numbers..?
I am making 12-14 depending on weather with my ported and polished m62 on a 3.0 pulley.
On a 100% stock setup. Stock exhaust, no intercooling and stock pulley I was getting around 12psi.
No with lsj header highflow cat and 2.5" downpipe to stock cat back, intercooled and stock pulley im seeing around 9psi
This is at sea level.
Im running a 3.065" smoothflow pully, stock internals, stock m62, and have never made more or less than 8lbs. I have no vacuum leaks and its been consistent with different gauges to test it. 8lbs, thats what i get.
04 Cav. 2dr. 5spd. My DD. 'Nuff said.
So the moral of the story is still that PSI is way relative to a multitude of external factors; altitude, air temp, etc.
"In Oldskool we trust"
roger. my 8lbs has destroyed m62 setups on l61's with over double the psi numbers. its all in the part combination and tune...which my tune blows right now and runs extremely rich, not to mention now one of my injectors and the fpr is leaking.
04 Cav. 2dr. 5spd. My DD. 'Nuff said.
yeah PSI is all relative. there also comes a point (on the M62) where a pulley will help more with torque then with horsepower. Seasons, and ambient air temp will also play a roll in how much boost you see, as will how restrictive (or not) your head and exhaust are. The more restrictive a system, the more PSI it will make. That DOES NOT equal more power though. You will see lower PSI numbers with cooler air then you will with hot air. There is a post on here somewhere about it...
I know, I forgot that temperature and sea level play a role in boost but I knew that as well lol. But if anyone is willing to enlighten me, and this forum on some more numbers, thatd be great.
