[Z06] Horsepower Differences
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Instructor
Joined: Aug 2009
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Horsepower Differences
What are the differences, if any, in the horsepower rating between the standard C5, 5.7 L engine (1999) and the Z06 5.7L engine (2003).
I now have both cars and I am truly amazed by the difference in power between the two cars. The standard C5 is an automatic, stock from the factory and the Z06 has the HalTech air intake, the Corsa Exhaust with X pipe, and a 6 speed.
I used to love my standard C5 with automatic transmission, but after driving the Z06 with the 6 speed, well let's just the say the experience is completely different now. I can honestly say that it's a thrill everytime I get into the Z06 and I can't seem to get enough of it. The power won't quit, it's absolutely amazing. It's funny, the first time my wife got in the car she got a little scared, now she really enjoys the power of the Z06 and doesn't even squirm when I open it up.
I bought my first vet 6 weeks ago, and the second 3 days ago, and I swear I want to buy a newer Z06. Wow have I got the fever!
I now have both cars and I am truly amazed by the difference in power between the two cars. The standard C5 is an automatic, stock from the factory and the Z06 has the HalTech air intake, the Corsa Exhaust with X pipe, and a 6 speed.
I used to love my standard C5 with automatic transmission, but after driving the Z06 with the 6 speed, well let's just the say the experience is completely different now. I can honestly say that it's a thrill everytime I get into the Z06 and I can't seem to get enough of it. The power won't quit, it's absolutely amazing. It's funny, the first time my wife got in the car she got a little scared, now she really enjoys the power of the Z06 and doesn't even squirm when I open it up.
I bought my first vet 6 weeks ago, and the second 3 days ago, and I swear I want to buy a newer Z06. Wow have I got the fever!
Intermediate
Joined: Oct 2009
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From: Carmichael CA
Stock specs for a 2003 are C5: 350 & Z06: 405 (but has found to be underrated and is closer to 425hp). The Z06 stock is also a couple hundred pounds lighter than a stock C5 of the same year whether it be a conv or hatchback.
Last edited by ChrisC503Z06; Oct 11, 2009 at 03:43 PM. Reason: Correction
Thread Starter
Instructor
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Thanks for the reply
That power is wicked. With the halteck air intake and the corsa exhaust with x pipe, do you have any idea how much extra that might add to the horsepower. I've only had the car a couple of days, and I'm still learning about the car. I do know one thing, it will be hard to drive anything else from this point forward.
Instructor
Joined: Nov 2007
Posts: 208
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From: Cookeville Tn
My kids call it the roller coaster...
I'm guessing 55hp between the two motors on paper but I've heard that the 405hp on the Z06 is a little on the conservative side.
Couple that with a lighter car and manual versus HP eating automatic and the difference would be like adding 100hp to that C5 IMO.
Safety Car
Joined: Oct 2004
Posts: 4,816
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From: Plano TX
Cat back exhausts generally are for sound and not horsepower. Exhaust restriction occurs from the restrictive exhaust manifolds and catalytic converters.. So from the catalytic converter on back to the mufflers the stock system is as good as any other out there. You might see 3-4 horsepower at best, if anything at all.. The halltech intake is worth 10-12rwhp..
The C5 Ls1 with an automatic has either a 2.73 or 3.15 gear ratio... The Z06 has a special close rato transmission (M12) unique to the Zo6 only and a 3.42 gear ratio.. This keeps the LS6 in the peak power zone through the gears The only thing a C5 Ls1 has is a higher top speed than the Z06
The C5 Ls1 with an automatic has either a 2.73 or 3.15 gear ratio... The Z06 has a special close rato transmission (M12) unique to the Zo6 only and a 3.42 gear ratio.. This keeps the LS6 in the peak power zone through the gears The only thing a C5 Ls1 has is a higher top speed than the Z06
Last edited by David426; Oct 11, 2009 at 04:05 PM.
Thread Starter
Instructor
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Peak power zone
You know, I think that best describes the difference I felt between the two cars. The Z06 really seemed like it had as much power in every gear and the accerleration didn't let up for a second. It was absolutely amazing. Thanks for the info.
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Drifting
Joined: Feb 2007
Posts: 1,993
Likes: 7
From: LaPine Oregon
345 hp
ya, its 345 hp in '99
And the '02-'04 LS6 have more potential for hp gains . Rolling Thunder says that they believe that the rated hp for the LS6 under rated.
And the '02-'04 LS6 have more potential for hp gains . Rolling Thunder says that they believe that the rated hp for the LS6 under rated.
Last edited by dieseldave56; Oct 12, 2009 at 05:00 AM.
Burning Brakes
Joined: Aug 2007
Posts: 831
Likes: 2
From: Houston Texas
Regardless of the crank rating for HP- the 2002 thru 2004 Z06 puts out at the wheels around 350 to 360 RWHP (with the 405HP engine). This is bone stock.
Had my 2002 Z06 Dynoed this past week-end and it had 366 RWHP before being dyno tuned and 374 RWHP after tune. This with a cat-back and CAI as only mods. By reference my car's before tune 366RWHP is on the high side for the 405HP (at the crank) engine.
Hope this helps.
Had my 2002 Z06 Dynoed this past week-end and it had 366 RWHP before being dyno tuned and 374 RWHP after tune. This with a cat-back and CAI as only mods. By reference my car's before tune 366RWHP is on the high side for the 405HP (at the crank) engine.
Hope this helps.
)
Thread Starter
Instructor
Joined: Aug 2009
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Anyone know if you can put a 3.42 rear end on a 99 C5 with automatic.
After driving it around with the standard rear end, I think that might make the car a little more exciting. I don't the top speed matters to me as much as I like the quicker acceleration. If anyone has done that, any ideas what the cost might be. Also, what are some of the issues I might need to be made aware of? Thanks in advance.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
After driving it around with the standard rear end, I think that might make the car a little more exciting. I don't the top speed matters to me as much as I like the quicker acceleration. If anyone has done that, any ideas what the cost might be. Also, what are some of the issues I might need to be made aware of? Thanks in advance.
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
Le Mans Master
Joined: Jul 2009
Posts: 9,526
Likes: 12
From: Los Angeles California
HAHA!!! My mom was scared out of her mind when I took her for a ride in my bone stock 2002 Trans Am WS6... I told her my Z06 was a LOT faster... She doesn't want me to show her.
