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2010SS

iTrader: (3)

Can you provide more info? Not objecting your statement just asking why? Since the max torque occurred before the bump... And it occurred on all three runs.. Could be clutch slippage but again how would that affect it? Like I said just asking as this is my first dyno day...

Matt M

When a dyno roller speed pickup glitches, it still tries to calculate acceleration of the drum. The average numbers will still be correct, but if it's reading too low for part of the pull, it has to read too high for part of the pull, and vice versa. Its not easy to tell if it glitched higher mph around 3000 rpm, or glitched lower mph at about 4000 rpm. It looks like it might have even glitched twice. Either way, the numbers aren't real accurate until it stabilized. Our dyno does something similar to this once in a while, in which case it will show something crazy like 850 hp and 1000 ft lb out of a lightly modded Cobalt, but only for about 100 rpm and then it smooths out. If their dyno did that every time for you, they need to fix something.

There definitely wasn't any clutch slippage on the pull in the video.

BYT*SS*TURBO

iTrader: (6)

Yea, the tach signal was jumping. He was one of the first cars to run, we had it straightened out a couple cars later.

I had basically the same setup and tune and made the same numbers, 346/414 on my car. No jumpy crap on mine, Ill post it up in a lil bit.

Matt M

If it was just the tach signal jumping, ask them for the hp graph based on mph only. Then it would be easy enough to figure the torque.

BYT*SS*TURBO

iTrader: (6)

https://www.cobaltss.net/forums/dyno...ct2010-232191/

o3nisoaso3

theres about to be a 2nd stock blower lsj to break 300whp! first ride tonight on rebuilt motor (snapped a lifter) went from stock to CAI, dual pass opt b, h/e, full 3" exhaust catless, meth 75/25, p&p head w/ supertech valvetrain. stock cams, i/m, bottom end, blower, tranny. had injectors go static just before 6200rpm. friday the car will have gm stage 2 pulley and injectors with a full tune, no dyno numbers yet tho. hopefully by end of summer car will have 2.7/2.6 pulley with a tb spacer and/or blower spacer tapped for meth... thats when the car is hoping to see 300whp+

BYT*SS*TURBO

iTrader: (6)

We get it... lol. Someone is happy (not hating, just stop reviving the old threads so people dont get confused please)

ebristol

iTrader: (4)

You should get this old threads locked.

tcbracing

iTrader: (1)

Just got done getting a dyno tune at ZZP (Thanks Turbo Tim!).

Here's the mods:

ZZP Stage 2 - 39# Injectors, 3.1 pulley
ZZP CAI
ZZP Downpipe with hiflo CAT, 2.5" Stainless Mandrel Bent Exhaust with Magnaflow resonator and Muffler

244hp - 214ft/lb with only 14psi of boost... Not too bad!! I'm happy!

Probably going to step up to 50# injectors and a 2.9 pulley in the spring.

Here's the sheet: http://i29.photobucket.com/albums/c2...12-20-2011.jpg

BlkWdoSS

iTrader: (7)

422whp/ 333wtq, I can post the graph and mods list if needed. Havent seen ralliartist around in a while though.

l8r,
PD