vettesurfer

I’ve owned several c5’s, but have never had any of them put on a dyno. I have heard just like many of you that the c5’s lose more power through the drive train than the f-bodies did. I do believe this to be true. My 98 c5, auto with the performance gear was rated at 345 hp at the fly wheel and my buddies’ 2001 z28 was rated at 310 hp. When we would race he would always pull on me and at the track would always have a few mph’s more than me. The reason I am bringing this up is that I don’t believe things have really changed that much when comparing the new c6 to the 05 GTO to drive train loss. Now I’m not saying that the GTO will beat a c6, but I was wondering how the two dyno compared to each other. They are both rated at the same hp and yes the GTO does out weight it, but it does have better gearing stock (346). Has anyone seen these two cars dynode stock?
Lets try to keep the GTO styling opinions out of this, that s not what this thread is about. I'm just wondering about drive train loss and if that is still they same.

AFVETTE

I don't know if there is any empirical formula's etc to determine the actual difference, but the IRS in the vette consumes more of the power being output than other rear suspensions. I believe it was the difference in drive train loss.

I'm sure others more knowledgeable will chime in.

Tom

Flareside

I would expect the C6 and GTO to have similar loses, because they share the rear independent suspension. The C6 is faster because it's around 500 lbs. lighter. The old F-bodies had a solid rear axle, so they didn't lose as much.

vettesurfer

So from what you guy's are saying its the IRS that made the cars lose more to the wheels not the rear mounted trans?

LS1LT1

Not sure about the GTO situation (IMO it does actually dyno less than the C6 in most cases, both cars have IRS if this means anything) but I can tell you about the LS1 F-body (Trans Am/Formula/Z28/SS). They were rated at 305hp (later 310hp) or 320hp for the Ram Air/Firehawk/SS models (later 325hp) but their LS1 was the almost the exact same motor as the 345hp (later 350hp) in the C5 (throttle by wire, slight exhaust manifold and EGR differences).
To date they are the only current/modern era car to be so grossly under rated from the factory, this was done strictly for marketing reasons as to not **** off Corvette buyers too much ...maybe for insurance reasons as well.
That is why you will find the F-bodies pulling on the C5s sometimes, they all dyno roughly the same as well regardless of the F-bodies solid axle. Though I do still think the rear mounted trans and IRS of the Corvette might hurt it's dyno numbers slightly.

yellow01

Like they said, the F-bods were never that far below the Y-bods in HP from the factor, add solid rear and for drag racing they are very close. Minus the Corvette tax on mods also makes them cheaper ot mod...there are a lot of fast SSs running around Dallas!

LS1LT1

Not sure about the GTO situation (IMO it does actually dyno less than the C6 in most cases, both cars have IRS if this means anything) but I can tell you about the LS1 F-body (Trans Am/Formula/Z28/SS). They were rated at 305hp (later 310hp) or 320hp for the Ram Air/Firehawk/SS models (later 325hp) but their LS1 was the almost the exact same motor as the 345hp (later 350hp) in the C5 (throttle by wire, slight exhaust manifold and EGR differences).
To date they are the only current/modern era car to be so grossly under rated from the factory, this was done strictly for marketing reasons as to not **** off Corvette buyers too much ...maybe for insurance reasons as well.
That is why you will find the F-bodies pulling on the C5s sometimes, they all dyno roughly the same as well regardless of the F-bodies solid axle. Though I do still think the rear mounted trans and IRS of the Corvette might hurt it's dyno numbers slightly.

vettesurfer

Well , with all that said I will let you guys know what happens. I picked up a 05 GTO auto to replace my wifes Grand Prix lease. Within the next couple of weeks I will be taken it to get dynoed along with my buddies 05 c6 auto. Then we can compare real numbers. I will say this, my wifes 05 GTO feels faster than my 98 c5 auto with 3:15 gears, but I will have to wait till I get it to the track next month to back that up.

Scissors

The average M6 C6 is turning up dyno numbers of 350 RWHP. So if 400 HP is accurate (and it's probably low, due to legal reasons,) then that means the C6 drivetrain is losing at least 12.5%.

Barely Legal

I drove an 05 GTO and it absolutely felt like a DOG. I would never buy one after that experience. I like the looks but it does not stop, does not go and does not handle. I could not get my foot between the clutch and wall to use the dead pedal either.

Brannon

I bought my wife a '05 6spd GTO. It's without a doubt a quick car and sounds great! Heading home the other day she wanted to run them. I was able to pull her quite a bit. I'm sure it was the difference in weight between the two cars.

vettesurfer

If thats what you call a DOG you must have a 10 second daily driver because though not as fast as a c6 the 05 GTO's are not dogs. You must also think all auto c5's are dogs then to because there not to far off from the 05 GTO's. I'll post the times when I get it to the track like I said and then mabey I'll agree with you, but I dought it.

Scissors

If the 05 GTO is a dog, then so is the C5 since they have the same acceleration and braking.

vettesurfer

Thanks Scissors, I could not have said it better myself. Corvettes are my first love and always will be, but too many people never gave the GTO a chance from the beginning including myself. After I drove the 05 I had a whole different view of the car. In fact in some ways I feel the interior quality in better than my c5. Strait line performance I would put this car up against a stock c5 (non ZO6) any day.

vettesurfer

Scissors, is that a dealer installed sun roof on your GTO?

Scissors

Yes. Technically, they sent it down the street to a professional sunroof installer.

And contrary to popular belief, it does not involve cutting a critical support, as the Holdens offer a sunroof as well.

My opinion of the GTO was completely changed once I finally able to drive one at last year's Autoshow In Motion. Because of how great it was, I purchased one to supplement the 'Vette.

vettesurfer

I just picked one up for my wifes every day driver last week and we love it.

dbvettez06

It would be a nice everyday driver , or , for the wife

TAL

You are forgetting the 2003-2004 Ford Mustang Cobra that was conservatively rated at 390hp. Many made 420hp-430hp bone stock.

I'm sure the 06 Z06 and 07 Cobra will be very conservativlely rated for insurance purposes.

Regardless; Ford and GM are going to rate their cars lower for insurance purposes.

This is good for all of us.

need-for-speed

While GM's published specs never changed, rumor had it that in 1999 the LS1 gained some HP when GM leaned the tuning. This seemed to be proven on dyno days when we had different year models dyno'd on the same machine, same day. 1/4 mile times also backed up the "rumor". Your friends 2001 Fbody would have benefited from the updated tuning. Also, the LS1 Fbody's were underrated. I think they had more than 310, but less than 345 (probably due to not having true dual exhaust. From what I saw many times, the Fbody would dyno the same as the C5 (at the wheels) becuse of it's solid axle, and all things being equal (driver skill), the C5 would edge out the Fbody in the 1/4 mile due to it's lighter weight and Cd (ask me how I know )