what i asked
HI there

i own a 2005 cobalt SS/SC with the m62 supercharger witch comes stock with the car. i recently found out that the m62 supercharger should not put out more then 10 psi because anything more then 10 psi can blow the blowers. but the cobalt SS/SC comes with stock 12 psi so i was wondering why would GM put the psi to 12 on the m62 if it should not be anything more then 10 psi. im asking this because i was thinking of putting a 3.1 or 2.8 pulley on the supercharger but now after hearing this information im having second thoughts about this. i hope you can help me out on this.

I also heard that eaton told GM that they should not put it more then 10psi because it is not recommended but GM went to do it anyways, but then again that just sounds like a roumer because why would Gm go beyond what the M62 can hold but then offer a 2.8 pulley in there performance upgrade and have warranty on it.

so i really hope someone there can help me out to understand what the truth is and what the max PSI of the m62 Supercharger on the 2005 cobalt ss/sc can hold.



thanks for your time hope to hear from you soon.



Joseph

what they said

Wow , I love hearing the rumors from the streets!
Eaton currently manufactures superchargers for GM to the GM specifications
Nothing more nothing less

You can make a supercharger pump as much air as it can hold, the PSI of the air can not and will not damage or " Blow " a supercharger
The damage is caused by over speeding to attempt to build boost , this over speed causes premature failure of such components as the bearings that had not been designed to perform at such high over speeds

Most street racers think by speeding up a supercharger gets more power, but as the old saying goes " if a little is good , more has to be better "
What most people don't understand is that if you over speed a supercharger to get more boost or pressure you are actually hurting the efficiency of the air charger as you beat-up the air so bad and this causes the charge temp to rise so high you actual have less power then if you left it stock or just took a small step as GM has with the pulley in the performance catalogue


may i add it took them a good month almsot to reply to my e mail...

 

Interesting. I can see them makig the m62 to GM specifications, but the question is what do they do to the m62 so that it can run 12.5 safely and efficently, if its really only meant to run 10psi. Either way we all run risks pushing our cars further and the supercharger lifespan will suffer for it.

 

The response email says that it really doesn't matter how high the PSI values are the supercharger life simply relies on the speed the supercharger is spinning. There is a maximum speed the components are good for not a max pressure.

 

All of the info in the reply could have been easily found in the ss.net archives dude. This info is nothing new to this site. Also, where the heck did you hear that 10 psi is the max safe level of boost? Psi-rpm speed will be completely different from car to car dude(ie, Cobalt, Cavalier, RSX...), depending on the motor's ability to breath in and expell the air charge from the blower.

 

Basically, The harde something it pushed, the faster it will wear out... Seems like nothing new there..

 

Well atleast give him some credit for trying. Comon sense deson't exsactly run rampent around the .net forums. Some people really can't figure that stuff out or don't do any searches.

 

Agreed. I think this was in respons to other threads on here where some ex engineer that said GM was knowingly running the supercharger at or past the breaking point and that they would not last long on the cars.

 

Yeah man when I first saw that post the guy made I thought to myself "Oh boy here we go the newbie members are gonna have a field day worrying about this one". If post like these aren't stickied or pop up offten enough "The lemmings will just keep jumping off of the cliff" know what I mean?

 

lol yeah i here ya. To many people believe everything they read/hear no matter the source.

 

A couple things to remember:

PSI isn't soley dependent on the S/C, your engine dictatets a lot of it. If you have a car with heads that flow extremely well, your boost will actually drop. Just like if you put a really restrictive head, your boost would increase because the air would require a greater pressure difference to flow across the restrictive head.

Our cars are intercooled. That means even if you are heating up the air because of high boost, your dropping the temps a bit on the way in the engine, so you can get away with more boost.