Took the car to get tuned on Tuesday. It was the hottest day of the year at 98 degrees,8% humidity at a mile high


Mods include-K&N intake, zzp mid header w/ catted dp, zzp stg 3 with dual pass, stealth heat exchanger, option b, 2.7, zzp adjustable tensioner, LS4 tb, gm stg1 axles, 80#injectors, e85, ottp stg2 cams, 82# springs


The boost fell off right around 7k, so that's where it stopped making power. Peak boost was 13.24, but fell down to almost 9 by 7500. I don't think my belt is slipping, new belt and I have and adjustable tensioner. Tuner though maybe since the blower isn't ported it might not be able to keep up.


Picked up good hp and tq across the whole rpm range. Started with 227hp and 214tq with the canned zzp tune. Car feels way smoother during pulls now, due to cleaning up the fuel trims. Ended up with 256hp and 233tq

Update-tighter belt held boost till7500 New hp270 235tq

 

That's super low. I would think with those mods it would be closer to 300s. From what I have seen.

 

Altitude makes a big difference.


OP is that an uncorrected number?

 

I'm not sure if those are corrected numbers. Heck I don't even know what that means haha. Yes I'm at high altitude, you loose a crazy amount of boost. I was lucky to hit 8psi stock, now I am around 13.

 

Do you have the dyno sheet?

 

Normally the numbers are corrected for altitude, temperature and barometric pressure, i.e. restated to sea level.

 

This is the printout they gave me.

 

I feel like I might have been able to get closer to 270 if I could of held 13psi to redline.

 

Do you know how much timing youre running? Graph looks good but it really shouldnt drop off like that.

 

Those are corrected numbers via SAE.

Those numbers are kinda low, it worries me they don't like the AFR. OP do you have a wideband installed?

 

The reason it drops off up top is likely due to the mid length header not the unported supercharger. Look into a long tune header if you're wanting to keep reving it out. Are you running a stock exhaust after the mid length?

 

I'm not sure how much timing exactly but I did ask him. He tried messing with it a little, but the car didn't really like. It made 1hp more and 2tq less with trying to throw more timing at it. Do you think the boost is falling off because it is a unported stock blower? Looking at the boost graph it seems to go down after 5k

 

You need more exhaust work. Also the car should pick up a lot of power with timing, on e85 you should be able to run about 24-26*

 

Yeah I have a catted midlength with stock catback. Zzp said throwing on the catback after the tune wouldn't effect if. I might look into long tube with 3 in catback now.

 

The long tube will help, going from a stock cat back to zzps will help a bit on the high end, but not make it needed for a re-tune

 

I should have went with the longtube, I just thought that it would be overkill. But the more time and money I keep throwing at it, the more I realize I should just go big. I would like to a tvs or nitrous maybe this fall.

 

When you do that PM me.

 

TVS is life

 

Gonna agree TVS>Nitrous

 

TVS+N2O>TVS or N2O

 

Im not sure which would be a better route the standard tvs or the 1320. I have a bung welded in for wideband and a 2gauge pillar from zzp. I don't know which wideband I want to install to keep it oem'ish looking. I can paint the silver ring so they match I just want to gauge face to be close. I might even go with a analog wideband, my digital sometimes gets annoying on my dsm.

 

The standard TVS is the 1320...

You want to get a wideband with a 0-5voltage output so your car can be tuned off dyno

 

Oh my bad. I guess I meant 1320 or 1900? I just don't want to get the smaller one and regret it down the road.

 

Look up some of the 1900 builds prior to buying. For most people the 1320 will be plenty, add nitrous and you certainly are good.

 

Iirc the 1900 is not a TVS style blower. It is the same style as the M62 just much bigger. The TVS is supposed to be more efficient correct?

Edit: My mistake. They are both TVS style blowers.