The sticker on the stock SS will say "Premium Fuel Recommended"
The GMTU replacement sticker says "Premium Fuel Required"

15 lbs boost is about stock boost numbers.

 

Welcome to the site, enjoy that new to you SS

 

Thank you Fireman. Gettin' my Trifecta tomorrow. Can't wait.

Boydie

 

So I am driving to work today and had to hit the gas pretty hard to get around some traffic and seems it was only boosting like 5 or 6 lbs in 3rd and/or 4th gear? Is that normal? Was boosting around 17 in 3rd gear a couple days ago. Maybe it's the way I pressed the gas as I was in low RPM's in 4th when I noticed it was sluggish after pressing the gas....

 

I would guess low RPM's. These car's won't "spool up" so to speak at low rpm's because it's the exhaust gases that spin the turbo. Plus, I'm sure there's some of that ECM torque management going on.

Any thing below 2k rpms, these little cars are out of their power band. At least on my 5 speed it is.

 

Yeah that's kind of what I figured out. My Mazdaspeed was a little different and spooled rather quickly even at low RPM (even though that's not really a good thing). Guess I need to stop trying to compare how I used to drive it vs. the HHR. BTW, loving my HHR. Too much fun!

Any thoughts on bypass valves vs. blowoffs? Advantages... disadvantages?

 

I'm running a Forge Bypass with the yellow spring for the GMTU. No real issues. Just seems to spool up a little smoother.
My old man, bad hearing doesn't notice any difference in sound.

With a blowoff, I'm pretty sure you would have to tune for it.

 

I love the "swoooosh!" of a blowoff valve... would have to check into needing tuning adjustments though. I wouldn't think it would be required since it just releasing to atmosphere but you guys know much more about these cars than me.

How do you like your exhaust? Looking to maybe upfit mine eventually also.

 

You can run the forge atmospheric release valve witout a tune, throws a code but some dont care. Matthew got a tune from Vince for it. Do you really want to make that fart noise every time you lift you foot from the gas ?

Btw. yes I am also a fan of the HP2 shorty's...plural.

 

& on the SS