[Z06] Disappointing dyno today
Team Owner
Joined: Jul 2003
Posts: 34,299
Likes: 1
From: [Enter Unoffensive Comment Here]
Cruise-In VI Veteran
Cruise-In VII Veteran
St. Jude Donor '06
Re: Disappointing dyno today (Y2K253SS)
On the dyno it's the gears, but I bet it feel like you have more when you're on the street. :yesnod:
Drifting
Joined: Oct 2002
Posts: 1,823
Likes: 1
From: If you can see the car behind you, your not going fast enough
Re: Disappointing dyno today (lager99)
Pumba... I am not sure about how it works, but i am pretty sure it has very little to do with friction... you would be better off to pm julio, lou, or any other tuners that do work with them to get a really good answer :cheers:
Drifting
Joined: Nov 2001
Posts: 1,684
Likes: 0
From: Jacksonville Florida
Re: Disappointing dyno today (Y2K253SS)
You will lose power going to the bigger (numerically) gears due to increased friction loss, I have seen 10 RWHP loss on the same dyno (and operator) going from 3.42 to 3.90. So add in different dyno, different weather, different operator and 4.10 gears and your reduction is not surprising IMO.
Dyno's are for tuning, comparing all the variables above is an exercise in frustration. Go drive and enjoy the car. The track is the only place to measure before and after performance.
Les
Dyno's are for tuning, comparing all the variables above is an exercise in frustration. Go drive and enjoy the car. The track is the only place to measure before and after performance.
Les
Team Owner
Joined: Aug 2000
Posts: 67,942
Likes: 1
St. Jude Donor '12
2012 Election Contest Winner
Re: Disappointing dyno today (ZO6Les)
You will lose power going to the bigger (numerically) gears due to increased friction loss, I have seen 10 RWHP loss on the same dyno (and operator) going from 3.42 to 3.90. So add in different dyno, different weather, different operator and 4.10 gears and your reduction is not surprising IMO.
Dyno's are for tuning, comparing all the variables above is an exercise in frustration. Go drive and enjoy the car. The track is the only place to measure before and after performance.
Les
Dyno's are for tuning, comparing all the variables above is an exercise in frustration. Go drive and enjoy the car. The track is the only place to measure before and after performance.
Les
No, it is not friction. Horse power is calculated as torque * RPM divided by 5252. Gears will change the RPM vs. torque relationship - e.g. it will move max torque to lower RPM, thus you run out of usable portion of RPM range. Plain and simple.
Safety Car
Joined: Aug 2002
Posts: 4,050
Likes: 229
From: Oxnard CA
St. Jude Contributor
Re: Disappointing dyno today (Y2K253SS)
Which gear did they do the dyno reading with. When I got mine dyno'ed, Andy used 4th to redline. He was saying because the gear ratio is 1:1. If you differ from the 1:1 ratio you'll get incorrect readings. Does anybody know what gear is 1:1 when you have 4.10 rear end?
Le Mans Master
Joined: Dec 2000
Posts: 7,096
Likes: 153
From: "Atlanta" Ga.
Re: Disappointing dyno today (robz)
Its the gears. I lost 19 hp with the gear swap and others have lost close to 20 as well. Dont sweat the dyno numbers. Your car will run alot faster now provided you get traction to the tires. Trust me, get some et streets and hit the track.
Burning Brakes
Joined: Oct 2001
Posts: 983
Likes: 23
From: Northeast Ohio
Re: Disappointing dyno today (Gonzo)
Here's my opinion, Those are inertia dyno's, they measure hp, by how fast that heavy drum spin's up. But your engine now has to spin up faster than it did before, just to make the same hp, and there's limit to how fast an engine will spin up, it's the same reason that a lighter flywheel makes more hp on a chassis dyno.
If you dyno'd in a higher gear, I'd bet some of your "missing" hp showed back up.
If you dyno'd in a higher gear, I'd bet some of your "missing" hp showed back up.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
10 Most Common Corvette Problems of the Last 20 Years!
Joe Kucinski
5 MOST and 5 LEAST Popular Corvette Model Years in History!
Joe Kucinski