the engine itself is perfectly fine til 7200rpm but the turbo porbaly will fall off considerably after 6500... The stage kit for the supercharged car puts my redline at 7k but i shift at 6500 even with the supercharger power levels off or falls after that..

 

found it!

from the creator himself...

 

If the motor can do it I still don't it's worth going past where the HP and TQ fall off because it's worthless. Staying in the power band is the best. I also plan on upgrading the Turbo but how much larger can we go?

 

i think it was synapse made a kit for the cobalt, put a gt2871r on there car and at 22psi made 383 and 367 something close to that and thats a other wise sotck car with downpipe , hard piping and intake. Also a new exhaust manifold

 

I hear that they now can modify the stock turbo to increase boost. Im new to the Turbo realm so i'm learning. If these engines can hold 7500rpms that proving that GM is doing their homework. I was just trying to make people understand that they don't need to push their engines past where the HP and TQ fall off the dyno.

 

82mm GT40 does an easy 900cfm, which is probably in the 600+hp range on a 2.0 motor. Or maybe you're thinking bold and looking at a 114mm GT47. You'll need a crowbar to fit it, and then a lot of patience to spin it up, but you're looking at 800-1000hp. Oh, don't forget to make a few mods to the engine so it doesn't asplode.

Absolutely. If you're gonna play, you've gotta pay.

 

i'm planning an 18G turbo down the line. i'm not going for outrageous power, but i've heard some nasty rumors about these turbos, and that they apparently won't last super long in any form of a modified car. good friend of mine worked for a Chevy dealer as a mechanic and received some training on the LNF for maintenance type stuff when they came out, and apparently they were told that any kind of modification could bring these turbos to their death as early as about 40K miles. he was the first place i've heard this, and i've ehard it a few others since then. maybe ChevyMgr knows something on this?

 

An 18g doesn't actually exist. It's a hybridized (bastardized) Mitsu TD05-16g and TD06-20g. It's also fallen well behind Garrett's feature set such that they're really not a very good choice any more. For about the price of the 18g, you can get a comparable (and much faster spooling, better bearing'd, better cooled, lighter, more reliable, and more serviceable) Garrett GT series. In addition, since you've got to have someone (or yourself) tune the ECM after the swap, you may be on your own with the choice, as others will not likely got the Mitsu hybrid route.

/2 cents

 

even without my Hahn tune, my auto has never had any trouble in the boost department. have always been close to 20 and above without the tune and better still with the tune, I think the highest I ever went was 27psi, and everything must have been perfect at that particular time.
in the last month that we have had the cold weather, the boost still will go up to 20 and above depending on the temps, I think only one time and this was hittting passing gear it did 16 psi, but it still runs great.
even the thread I did on the 0-60 times showed how much of an improvement I did going from a best 0-60 6.75 stock down to a 0-60 5.6 with the tune, to date, haven't really done any runs lately.
But for you auto drivers there is a difference with and with out the TC engaged. I always run in Launch Control, except when the road conditions are slippery.
Maybe some day I will do the dyno, but either way I am very happy with the performance the SS has given me so far, thinking about the new air system when it becomes available, who knows I may be in the low 5's after that is installed

 

Did a few test runs today around town and the car shifts at 6000 to 6200rpm.