What should a stock Zzz be putting down for HP?

[Heavy Duty]

I had a friend Dyno his Zzz last week and it turned 350 Horses at the wheels. That is about an 8.5% difference between the crankshaft Vs rear wheels. I thought that there would only be about a 5% difference since these cars have manual trannys. I was at Carlisle last summer and saw a stock Zzz turn 380 horses....which would be about a 5% difference and IMO would be about right. Is there that much difference between each car?

 

[Heavy Duty]

Boy...I guess no one has dynoed a stock Z-06. Must be something we don't want to talk about .



H.D.

 

[Patrick]

HD,
The better question is, how many Z06 owners have kept their cars bone stock, right down to the original factory exhaust?

You may actually have to work to find Z06 owners who haven't done anything to it.


-Patrick

 

[Heavy Duty]

HD,
The better question is, how many Z06 owners have kept their cars bone stock, right down to the original factory exhaust?

You may actually have to work to find Z06 owners who haven't done anything to it.


-Patrick

Thanks CORed91,
I just got my Zzz last month so I guess I must be one of the few that still has a stock Zzz.

I went with a friend last week to get his tuned and dynoed. I was suprised that before the tuning he only put down 350 horses. The guy doing the tuning said that was about right for a stock Zzz. But i wanted to make sure that he wasn't yanking my chain a little. There is either a huge HP drop or these cars are not really 405 horses at the crank. I could consider a 55 Hp difference if these cars had AutoTrannies in them. But with a manual I don't think it should be that big of a drop in horse power to the wheels.

I do plan on doing some mods to mine later. Right now i gotta get the garage up so it will have a home.

Thanks again for the post. I guess not many people keep these cars stock.

H.D.

 

[DRTH VTR]

Zzz???

 

[Edmond]

HD,

That 350 to the wheels is right on target: 350rwhp/.85=412 at the flywheel.

GM does tend to underrate the Corvette hp numbers a little bit. If we took the 405 advertised hp and: 405*.15 (15% is usually the number used for loss from flywheel to trany), it would lose 61hp. 405-61=344 hp.

 

[Heavy Duty]

HD,

That 350 to the wheels is right on target: 350rwhp/.85=412 at the flywheel.

GM does tend to underrate the Corvette hp numbers a little bit. If we took the 405 advertised hp and: 405*.15 (15% is usually the number used for loss from flywheel to trany), it would lose 61hp. 405-61=344 hp.

Thanks Edmond. Thats does it. Quick as the garage is built I will be modding the hell out of it:naughty:. I will be shooting for at least 400 at the wheels. My sons just had their WS6 tuned with a new cam and it put down 378 horses at the wheels. Got the e-mail from them this morning. So now the bragging rights are in their court. As you can see, we have our own little HP war going on. So now I've got to get to work and defend the corvette's image:bang.

H.D.

 

[Edmond]

Thanks Edmond. Thats does it. Quick as the garage is built I will be modding the hell out of it:naughty:. I will be shooting for at least 400 at the wheels. My sons just had their WS6 tuned with a new cam and it put down 378 horses at the wheels. Got the e-mail from them this morning. So now the bragging rights are in their court. As you can see, we have our own little HP war going on. So now I've got to get to work and defend the corvette's image:bang.

H.D.

HD,

You know as well as I do that it takes more than raw HP to get going. You have the advantage over that WS6 in many categories:

weight-I think those are roughly in the 3400 lb. area. I think the Z06's are about 3150 or so?

suspension-the Z06 suspension is superior, it puts the power to the ground very well. 1.0g in lateral acceleration.

aerodynamics-the Z06 has a very good coefficient of drag.

it's a Corvette-that is just mojo in itself!

You could probably pick up 20-25 at the wheels with long tube headers, high flow cat and a lesser restricting exhaust.

Put a Vortex or Vararam in there and you've got a few more ponies.

 

[Heavy Duty]

HD,

You know as well as I do that it takes more than raw HP to get going. You have the advantage over that WS6 in many categories:

weight-I think those are roughly in the 3400 lb. area. I think the Z06's are about 3150 or so?

suspension-the Z06 suspension is superior, it puts the power to the ground very well. 1.0g in lateral acceleration.

aerodynamics-the Z06 has a very good coefficient of drag.

it's a Corvette-that is just mojo in itself!

You could probably pick up 20-25 at the wheels with long tube headers, high flow cat and a lesser restricting exhaust.

Put a Vortex or Vararam in there and you've got a few more ponies.

Edmond, thanks. i do know that it takes more than just HP to get going. I don't intend on going into the engine (i.e. cam) but yes the headers, exhaust, intake mods and a good tuning should get me close to where I want to be. Right now, I do think that with the added HP the WS6 is putting down that on the strip it would be a close race. But you are right in that in a road race the WS6 would be no match for the Z-06. I also know that there is always someone faster than you...you just haven't found them yet. The good thing going for the vette is that they are still built...the WS6 Firebird is history. I keep reminding those two of mine that if the WS6 was such a hot car then why did GM stop building them. That always gets them on the war path:L.

thanks again for the comments. When time comes I'll check and see what the best solution is to upping the ponies.

H.D.

 

[Edmond]

I also know that there is always someone faster than you...you just haven't found them yet.

Whenever I hear that, I always get a philosophical thought..."If there is always someone faster than you, where does it end?" :L

 

[02coupe]

I'm in the process of doing price comparisons for custom engine build job for my 66 chevelle. Most engine builders I've talked to say to deducted 17-20% for a manual shift car with newer trany's and 20-23% for automatics. According to what they've said it's pretty much the same for any car.

 

[MsSchroder]

I keep reminding those two of mine that if the WS6 was such a hot car then why did GM stop building them. That always gets them on the war path:L.
H.D.

I just love a good family rivalry!
My son gave up on the HP battle and now is going for the power to weight ratio (motorcycles). You just can't win :L

Mine is still stock but never dyno'ed. Yeah, I'm afraid I'll be under-impressed.


Tammy

 

[Heavy Duty]

I just love a good family rivalry!
My son gave up on the HP battle and now is going for the power to weight ratio (motorcycles). You just can't win :L

Mine is still stock but never dyno'ed. Yeah, I'm afraid I'll be under-impressed.


Tammy

I know what you mean Tammy. Those two of mine saved all of their life guarding money from this past summer in an effort to try and make the WS6 better than the Z-06. When we/they bought the WS6 it was understood that THEY would make the payments. Well....since they have blown their money on the engine guess who has to make the payments or at least help make the payments? I guess I could repo the car:L.

I haven't dyno'ed mine yet either. I guess if we don't we can always claim ignorance .

You guys have a happy holidays.

H.D.

 

[Jim M]

I dyno'd my 2004 Z at Corvettes at Carlisle this past August. Bone stock, and I mean just as it left the factory, it turned out 360.5 rwhp. The general consensus is there is about a 15% parasitic horsepower loss for manual transmission cars and 18-20% for automatic cars. I was happy with my results, this equates to about 424 horsepower at the crank (rwhp divided by.85). Seems like most "stock" 04 Zs dyno from about 355 to 365 rwhp. This is on a Dynojet dyno.

Jim M

 

[Heavy Duty]

I dyno'd my 2004 Z at Corvettes at Carlisle this past August. Bone stock, and I mean just as it left the factory, it turned out 360.5 rwhp. The general consensus is there is about a 15% parasitic horsepower loss for manual transmission cars and 18-20% for automatic cars. I was happy with my results, this equates to about 424 horsepower at the crank (rwhp divided by.85). Seems like most "stock" 04 Zs dyno from about 355 to 365 rwhp. This is on a Dynojet dyno.

Jim M

Jim,
I was also at Carlisle this past August. Saw a Z being dyno'd and was very impressed with the numbers it turned out (~380 HP) and the way it sounded at WOT. I spoke to the owner about it and he said that the only thing he had done to it was exhaust and intake. I was so impressed with the Z I bought one. I have plans on going back to Carlise this summer with the Z and see what it does on the dyno. Can't wait.

H.D.

 

[Jim M]

H.D.
Congratulations on getting the Z, I think it's a great choice. If your's is stock, you should dyno somewhere around my figures, give or take a few either way. I wanted to dyno mine stock so I had a baseline before doing any mods.
I go to Carlisle every year and plan on attending next year too. It is definitely Corvette heaven.

I spoke to Lou Gigliotti (LGM) who races a Corvette in the SCCA World Challenge and has a Corvette shop, just in case your not familiar with him. Anyhow, he told me that with long tube headers with high flow cats, a good cold air intake and tuning, my car or most any 02-04 Z for that matter, would develop about 400 horsepower at the rear wheels. I think getting 380 rwhp with only intake and exhaust is possible, but I suspect maybe headers or a little tuning or other boltons might be necessary. If only a catback and intake were on the Z you saw dyno'd, then that Z has an extremely strong engine. Generally a catback system on a Z is not going to produce more than a few horsepower over the factory TI system, and you can probably figure on 10-12 rwhp for a good intake. There's plenty of horsepower to be had, how much do you want to spend.

Anyhow, have a great holiday and enjoy the Z.

Jim M

 

[Heavy Duty]

Thanks for the good info Jim. I do think it is a good idea to dyno and find out what base HP is on the car. That way after adding a few goodies you will findout how much they helped.

Maybe we'll get the chance to meet up at Carlisle. Until then, you too have a great holiday.

H.D.

 

[S-TEE]

Differences in dyno's gas, temp, etc. will create a range in figures for the HP ratings. Here in SoCal, I've heard that 350-360 HP is about the norm for a stock Z.

I turned a 358HP/349TQ on a 70* morning, last June, running 92 octane. My only mod at the time was a set of Borla 2-tip Stingers, so it was pretty much the same as stock. Must be nice when you can get gas of a higher octane from the pump...

 

[Edmond]

Has anyone ever done a study where they dyno'd the car after every mod to prove how much of a gain they really got?

TPIS sort of did something like that with a 2001 Z06:

"We did indeed get a big bang for the buck. The first thing that we tested was our Air Force 3 Air Filter Asembly. The baseline rear wheel horsepower numbers on this car were: 325.4 ft. lbs. and 322.3 hp. This was about ten less each than we were hearing other Z06's producing. With the Air Force 3 installed and the screen out out of the Mass Air Sensor, the RWHP climbed to 332.6, a 10 hp jump at the rear wheels.

Next we installed our TPIS header. This time the power jumped to 354.9 and the torque went to 353.6. That's 22 rwhp and 22 ft. lbs.

For the next step, we added our TPIS spark plug wires and a set of the Bosch platinum +4 spark plugs. We saw a solid 2 rwhp and 2 ft. lbs.

The final item was a CNC'd and ported Throttle body. This gave a final number of 359.1 rwhp and 357.5 ft. lbs.

The total gain is an impressive 36.8 rwhp and 32.1 ft. lbs. of torque. At every point in the power band, we exceeded the factory power and torque numbers.

We do not use our Cold Air Cover on the chassis dyno because it is designed to take advantage of the air pressurizing the radiator cavity and wll actually show less horsepower if left on for that type of testing."

 

[slong]

365 @ the rear is normal.