Rear Wheel Horsepower???
Former Vendor
Joined: Mar 2004
Posts: 1,518
Likes: 7
From: Valencia CA
I'm betting closer to 290....
The 97 and 98's didn't make as much as some of the newer Vettes due to small changes GM made along the way...more internal and just part of the constant evolution and refinement of the vehicle.
Also, big variable here is what dyno and who's facility, but I think if you went to 10 different places your average would be closer to 290-295 RWHP (assuming bone stock).
Have fun...you can only go up from here. The first 50 extra HP is relatively easy...its gets more expensive and more time consuming from there...
Tony M.
The 97 and 98's didn't make as much as some of the newer Vettes due to small changes GM made along the way...more internal and just part of the constant evolution and refinement of the vehicle.
Also, big variable here is what dyno and who's facility, but I think if you went to 10 different places your average would be closer to 290-295 RWHP (assuming bone stock).
Have fun...you can only go up from here. The first 50 extra HP is relatively easy...its gets more expensive and more time consuming from there...
Tony M.
Advanced
Joined: Mar 2005
Posts: 84
Likes: 5
Originally Posted by Biggieflan
Wow!! I'm somewhat dissapointed by those numbers, but I can live with them, and do nothing but improve them. Any advice on the best mods for that provide the best horsepower??? 
With an aftermarket intake, headers, and cat-back, you should see gains in the vicinity of 20 to 40 horses, depending upon the configuration you choose to install.
Melting Slicks
Joined: Apr 2005
Posts: 3,418
Likes: 1
From: Chicagoland Area IL
Originally Posted by Tony Mamo
I'm betting closer to 290....
The 97 and 98's didn't make as much as some of the newer Vettes due to small changes GM made along the way...more internal and just part of the constant evolution and refinement of the vehicle.
Also, big variable here is what dyno and who's facility, but I think if you went to 10 different places your average would be closer to 290-295 RWHP (assuming bone stock).
Have fun...you can only go up from here. The first 50 extra HP is relatively easy...its gets more expensive and more time consuming from there...
Tony M.
The 97 and 98's didn't make as much as some of the newer Vettes due to small changes GM made along the way...more internal and just part of the constant evolution and refinement of the vehicle.
Also, big variable here is what dyno and who's facility, but I think if you went to 10 different places your average would be closer to 290-295 RWHP (assuming bone stock).
Have fun...you can only go up from here. The first 50 extra HP is relatively easy...its gets more expensive and more time consuming from there...
Tony M.
Le Mans Master
Joined: Sep 2004
Posts: 7,027
Likes: 6
From: Shiloh Ohio
Originally Posted by Tubes
Typically, the best way for the LS1/LS6 engines to gain power is to make them breathe a little better, meaning intake and exhaust. There are numerous aftermarket intakes available, and most of them generate roughly the same gains in horsepower, plus or minus a few horses depending upon the style you choose. Exhaust also plays a role, so a good set of headers wouldn't hurt either. Long tube headers create more power than short headers, but both of them have their pros and cons on installation, error codes, and smog inspections. Also, to some degree a good cat-back system might help, but actual horsepower gains with a cat-back are questionable, and you may or may not see any gains. Cat-backs are generally there to set the tone of the exhaust.
With an aftermarket intake, headers, and cat-back, you should see gains in the vicinity of 20 to 40 horses, depending upon the configuration you choose to install.
With an aftermarket intake, headers, and cat-back, you should see gains in the vicinity of 20 to 40 horses, depending upon the configuration you choose to install.
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Melting Slicks
Joined: Dec 2004
Posts: 2,322
Likes: 2
From: New York NY
Cruise-In VI Veteran
St. Jude Donor '05
Originally Posted by Fastguy
We dyno'd tw0 M6 98's, mine with 137,000 miles and my friend's with 100k less and they were both around 312.
Melting Slicks
Joined: Mar 2005
Posts: 2,534
Likes: 118
From: Columbia, SC
I have a 2000 FRC (MM6) that I put a 2004 LS1 replacement engine into (GM pt no. 89017548) because I dinged the original eng at a track day. The new block is an LS6 block, with LS1 (241 casting) heads, but don't know what cam is there, assuming '04 LS1 internals, NOT LS6 as that is obviously a different part no. The only mods are a Z06 air box, K&N air filter, LS6 intake, Z06 cast iron headers, H pipe, and Ti cat backs (complete '03 Z06 stock exhaust system). I am using the original 2000 (smaller) MAF and throttle body, and original (26#) injectors. I have not opened the engine as it is under a 3 yr/100K warranty from GM.
It consistantly dynos SAE 330 RWHP/344 RWTQ on A&A's dyno after a tune. It dynoed SAE 324 RWHP/338 RWTQ prior to the tune. I never had the original engine dynoed before I broke it. Charlie (the tuner) and Andy (the owner) at A&A both say those were very strong stock LS1 numbers, as they usually expect around 300 RWHP from a stock motor. That is approx 390 crank HP given 15% drive train loss. His dyno is supposed to be conservative (SAE corr factor of .99) due to their close proximity to the coast.
Given those numbers, I would think they made some improvments to the LS1 over the years.
It consistantly dynos SAE 330 RWHP/344 RWTQ on A&A's dyno after a tune. It dynoed SAE 324 RWHP/338 RWTQ prior to the tune. I never had the original engine dynoed before I broke it. Charlie (the tuner) and Andy (the owner) at A&A both say those were very strong stock LS1 numbers, as they usually expect around 300 RWHP from a stock motor. That is approx 390 crank HP given 15% drive train loss. His dyno is supposed to be conservative (SAE corr factor of .99) due to their close proximity to the coast.
Given those numbers, I would think they made some improvments to the LS1 over the years.
Melting Slicks
Joined: Dec 2004
Posts: 2,322
Likes: 2
From: New York NY
Cruise-In VI Veteran
St. Jude Donor '05
Originally Posted by Minkster
I have a 2000 FRC (MM6) that I put a 2004 LS1 replacement engine into (GM pt no. 89017548) because I dinged the original eng at a track day. The new block is an LS6 block, with LS1 (241 casting) heads, but don't know what cam is there, assuming '04 LS1 internals, NOT LS6 as that is obviously a different part no. The only mods are a Z06 air box, K&N air filter, LS6 intake, Z06 cast iron headers, H pipe, and Ti cat backs (complete '03 Z06 stock exhaust system). I am using the original 2000 (smaller) MAF and throttle body, and original (26#) injectors. I have not opened the engine as it is under a 3 yr/100K warranty from GM.
It consistantly dynos SAE 330 RWHP/344 RWTQ on A&A's dyno after a tune. It dynoed SAE 324 RWHP/338 RWTQ prior to the tune. I never had the original engine dynoed before I broke it. Charlie (the tuner) and Andy (the owner) at A&A both say those were very strong stock LS1 numbers, as they usually expect around 300 RWHP from a stock motor. That is approx 390 crank HP given 15% drive train loss. His dyno is supposed to be conservative (SAE corr factor of .99) due to their close proximity to the coast.
Given those numbers, I would think they made some improvments to the LS1 over the years.
It consistantly dynos SAE 330 RWHP/344 RWTQ on A&A's dyno after a tune. It dynoed SAE 324 RWHP/338 RWTQ prior to the tune. I never had the original engine dynoed before I broke it. Charlie (the tuner) and Andy (the owner) at A&A both say those were very strong stock LS1 numbers, as they usually expect around 300 RWHP from a stock motor. That is approx 390 crank HP given 15% drive train loss. His dyno is supposed to be conservative (SAE corr factor of .99) due to their close proximity to the coast.
Given those numbers, I would think they made some improvments to the LS1 over the years.
Safety Car
Joined: Jun 2004
Posts: 4,969
Likes: 534
From: Witness Protection Program Somewhere, USA
2026 Restomod of the Year Finalist
Originally Posted by Icemanskis
Those are pretty high numbers. Was this on a chasis dyno, mustang dyno? Were the numbers SAE corrected? 97-00 vettes were rated at 345 engine horsepower and 312 puts you at 359 on an MN6. No mods whatsoever, not even an aftermarket intake??
Absolutely correct. My 04 MN6 bone stock, but with questionabl gas in it, dynoed at 291. Started running Chevron and had the LS1 edit done and in worse air, it made 313HP, which is considered on the high side.#'s much higher, like stated above are
. Sorry but this is one of my pet peeves ever since a buddy of mine was told his stock 00 MN6 made 345 RWHP. Do this day he will argue that this is accurate. 
Melting Slicks
Joined: Mar 2005
Posts: 2,534
Likes: 118
From: Columbia, SC
Originally Posted by Icemanskis
those are nice numbers, but they seem pretty realistic considering you are running ZO6 full exhaust, ls6 intake, and ZO6 airbox. And you have been tuned. your engine is still very strong though
