colderbythelake

I have read something that said Chevy under rated the zo6 at 405 hp. I was wondering if that was true. Anyone dyno a stock zo6? Am open to any thoughts on this. Thanks.

Millenium Z06

Most C5 Z's dyno 350-360 stock. Figuring a 12-15% loss the factory number is low by 5-15 hp.

eps930

Sadly no matter what the actual Z06 factory stock HP may be it still needs more. "405" will be many Mustang's, 911's and rice burner's bitch. Step-up and add some boost to make the Z06 perform as well as it should.

EPS

Sox-Fan

12,500 miles. Stock other than a vararam. There was another thread here within the last day or two were guys were listing stock dyno results. I seem to be about average.

danziger

My Z16 put out 355rwhp when stock with 18K miles on her. Math would say that GM slightly underrated the LS6 in mine.

danziger

Far fewer cars match the power to weight, power under the curve, available traction and balance to match the C5Z. 13 years later and the C5Z is still formidable in stock form and hard to beat in bang-for-buck.

marty mar

Don't forget the aerodynamics, and close gear ratios. These cars are no mustangs or ricers bitch when driven properly. (13-14 GT500s) are the only exception.

eps930

Eo chop chop, que kang tao eouu! Not shifter yett Banzai!!!

Fast and Furnace

BoostedEBZ06

Not sure if serious...

racebum

tires are always the limiting factor. if you want something that wears well we still don't have tire tech that will really plant more than 360-400whp unless the car is AWD

you can go softer, or, you can use electronics but automotive performance has been limited by street tires for quite some time

i just can't stand burn out machines on the street. they aren't fast unless you're one of those people that measures everything in straight lines, they are difficult to drive at the limit and generally get crappy mpg

it's like you come into a corner, nail a great line coming out of the apex, then, you can't use the gas pedal until the car is fully straight or you'll just spin it around from having so much power on tap.

GM Fan

I don't buy the underrated stuff. Stock LS6 dynos are around 25-30 rwhp lower on average than your average LS3 dyno. (say 350-360 rwhp vs 380-390 rwhp). That difference for 405 vs 430-436 crank HP seems right on, and those LS3s are SAE certified for their rating, they should be spot on.

No real room for the LS6 to be significantly underrated, discounting dyno and individual engine variances since we're talking averages...

bikeriderga

those are really good numbers. Did you get a custom dyno tune as well?

Toque

Bought my 2004 Z06 in March 2004.

Bone stock dyno that same spring...

Sox-Fan

Yes, what you don't see there are all the pulls after the tuning started

Pchild

@ 12% drive train loss that puts you spot on 405HP. I'd say you're pretty darn close to what GM claimed. Unless someone has better numbers on drive train loss for the C5 Z06... I always estimated 13%, but I may start going with 12% from your dyno numbers Toque.

halp

Looks like a tune will buy about a 7% increase for a stock C5Z with a CAI.
Is this correct?

dagon138

I don't have a before dyno, so take it for what it's worth.
Mods at the time were Blackwing, and tune...Borla stingers if those even count.

bikeriderga

Tune makes a big difference. Before the tune on my 03 Z06 with Corsa Catbacks and Vararam, it was good. After tune, it was BAD!!

Note: I was throwing lean codes before the tune.

Toque

I think GM underrated the motors a little.
Imagine what would happen if some car's did not dyno what they should ?
GM would be SMART to make them a little more powerful than the badge on the side.

I always read its 15% for a manual.

Toque

WannaC5Z

A Dynojet is only about 5-8% loss whereas a Mustangdynomometer is 10-12% loss. It depends on the brand of dyno.
My buddy just sold a 2002 911 Turbo with the X50 package rated at 450hp and I have driven several late model Mustangs. My buddy's 911 would pull me on the highway but would be a close 1/4 mile race. Only the GT500's with aftermarket pullies (pre 2013) will beat a C5Z. These cars are the best bang for the buck n/a'd cars out there IMO.