For those experienced with HPTuner on the LSJ ...

Can we lower the boost (I'm not talking about the first gear but whatever which gear is) for say at high rpms on the LSJ ?

It could be a great idea to run the smallest possible pulley for highest possible low end torque, and to lower the boost for the high rpms, thus getting a more efficient setup producing less heat at high rpms and getting also a better differential pressure through the injectors ...

Someone ?

 

I believe there is a way but im unsure of how to. Maybe torque management settings for gear 2(controls all gears after 2nd.)

 

I'd PM Denny about that, he's been running his car that way. Said it worked out really good. I'm wondering if it still makes extra heat though because the blower is still spinning fast.

 

The thing is that the supercharger will still be overspinning thus creating alot of heat. So that would not be a good setup. Just get a more efficiant FI.

 

torque managment>supercharger>boost limit 1st or second gear. it's on the right had side of the screen near the top if it's an 05. the 06-07 is in the center section near the bottom.


depending on the year of car, you can limit it every gear, if it's an 05. or you limit it in 2nd and it affects all gears.

take your boost level and do the math against 100% to get the desired boost level you want

 

It COULD be true however we need facts from people who tried it ! Because for that particular blower, at high rpms (14000+ RPM) there is a 50+ degrees heat difference for as small as 5 psi difference. Also the fact that the power to spin it will be less.

 

Well this whole idea came to my mind a while ago. So I went and looked it up on here and from what I undertood it was an inefficiant way to setup your system. I belive it worked so well for denny because he has meth and that would cool the charge off from the extra spinning.

 

The only real safe way to run a 2.5" is with meth. Meth is a great idea.

 

That is not true at all. The safe way to run a 2.5 is with cooler intake temps and a good tune. Sure this is what he said above me but you don't need Meth to make this happen. A second heat exchanger would do the job along with lowering the temperature your fan kicks on. Then make sure your running a bit rich at WOT and you will be fine.

Other things to consider are your exhaust restrictions (restrictions in general are bad because it takes more boost to make the same hp) as the more restriction the higher boost you will see which is not a good thing, free up as much restriction as possible and you can make more hp with lower boost which will make your motor happy.

 

I agree, no matter what Meth is the only half safe way to run a 2.6" or smaller!

 

please clarify.

i have HPT'd many a LSJ, in all year segments from my 05 to two 07's and a **** ton of 06's.

if i am reading this rite, your saying that on an 05 you can do each gear and on 06, ect you use 2nd for the rest of the gears, correct?

can i get a screen shot or brake down as to how its possible to control boost in 3rd,4th, and 5th?

 

in the 05's you can limit every gear. this was changed in the 06-07 cars. to limit boost above 1st gear, you have to do it in the 2nd gear field. this limits the boost in all gears.

i can't do a screen shot till i get home later tonight, but i can.

here is the how too for the 05 cars

https://www.cobaltss.net/forums/showthread.php?t=61804

 

OK thanks for the link that was exactly what i was thinking about. I'm glad I own a 05 Cobalt SS/SC )

 

me to!!!

(i think i screwed myself by updating to an 06 OS tho)

 

Seriously? I thought you had an 06 :/ But I guess your mileage makes an 05 make more sense.

I know you like how you teach me and then someone posts something that has to do with something similar.

 

your still spininng the blower at those speeds way past its redline,
regardless of whether your using the boost.
so basically your still going to be wayyy past efficiency for the blower, and pouring superheated air into the engine.

The theory is solid, you will get boost earlier,
but the blower will still be a flamethrower, regardless of whether your using all the boost or not.

 

^^That is what I was trying to say. TY

 

Sure I agree that is true but thats why you try and get your intercoolers to cool as much as possible to cool the charge to help rid the flame thrower affect.

 

it is possible to do that.

i dont think it would make less heat though. the supercharger will still be spinning at the same speed(making same amount of boost) , it'll just be expelling the extra compressed air through the boost bypass valve.