Fastest Stock 93-97 Camaro Z 28
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Joined: Jul 2005
Posts: 9,507
From: Okemos, MI
So, why does the 95 California emissions 2 cat car rate 275 HP when the 96-97s have 285 if all the difference is in the number of cats? Seems curious. The extra cat obviously was not added for HP gains.
If even the single cat system was restrictive, then adding an aftermarket cat back would produce little, if any, HP gains (but it does add HP). I just can't buy the whole 2 cat extra flow scenario [= HP].
If even the single cat system was restrictive, then adding an aftermarket cat back would produce little, if any, HP gains (but it does add HP). I just can't buy the whole 2 cat extra flow scenario [= HP].
Registered User
Joined: Apr 2007
Posts: 927
From: Az
Absolutely bone stock my car dynod a pitiful 231/270 through an A4 with 70k miles on the second motor.
Oh and that's without doing my own tune up or anything to it. I had no idea what was going on in the car. No idea on even spark plug gap or even the brand!
That's an 18% drivetrain loss from the supposed 285 stock hp in 97. The motor was from a 96 WS6... not that they are any different.
Oh and that's without doing my own tune up or anything to it. I had no idea what was going on in the car. No idea on even spark plug gap or even the brand!
That's an 18% drivetrain loss from the supposed 285 stock hp in 97. The motor was from a 96 WS6... not that they are any different.
Last edited by LSWHO; Jan 29, 2008 at 10:18 PM. Reason: more info
Registered User
Joined: Jul 2002
Posts: 3,768
From: Friendswood, TX, USA
So, why does the 95 California emissions 2 cat car rate 275 HP when the 96-97s have 285 if all the difference is in the number of cats? Seems curious. The extra cat obviously was not added for HP gains.
If even the single cat system was restrictive, then adding an aftermarket cat back would produce little, if any, HP gains (but it does add HP). I just can't buy the whole 2 cat extra flow scenario [= HP].
If even the single cat system was restrictive, then adding an aftermarket cat back would produce little, if any, HP gains (but it does add HP). I just can't buy the whole 2 cat extra flow scenario [= HP].
GM normally under rates their HP numbers, so they don't get into the kind of trouble Ford did with their Cobra.
GM normally does not lie about HP numbers.
Without being able to dyno every 93-97 V8 Camaro, how can you say that generally one year will be faster then another? What basis are we going to use?
You know that individual dyno numbers are useless as no two dyno's will give the exact same reading, and individual cars very. The weights for all years 93-97 are listed at 3436/3521 coupes/converts, according to one source. So there should be no advantage there.
So in my opinion the only tested, reliable source we have is the manufacture.
I don't see the point of the question. In reality a race between any two "stock" Z28 coupes will come down to driver.
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Joined: Dec 1969
Posts: 27,727
From: Little Rock, AR
Couple of points.
GM normally under rates their HP numbers, so they don't get into the kind of trouble Ford did with their Cobra.
GM normally does not lie about HP numbers.
Without being able to dyno every 93-97 V8 Camaro, how can you say that generally one year will be faster then another? What basis are we going to use?
You know that individual dyno numbers are useless as no two dyno's will give the exact same reading, and individual cars very. The weights for all years 93-97 are listed at 3436/3521 coupes/converts, according to one source. So there should be no advantage there.
So in my opinion the only tested, reliable source we have is the manufacture.
I don't see the point of the question. In reality a race between any two "stock" Z28 coupes will come down to driver.
GM normally under rates their HP numbers, so they don't get into the kind of trouble Ford did with their Cobra.
GM normally does not lie about HP numbers.
Without being able to dyno every 93-97 V8 Camaro, how can you say that generally one year will be faster then another? What basis are we going to use?
You know that individual dyno numbers are useless as no two dyno's will give the exact same reading, and individual cars very. The weights for all years 93-97 are listed at 3436/3521 coupes/converts, according to one source. So there should be no advantage there.
So in my opinion the only tested, reliable source we have is the manufacture.
I don't see the point of the question. In reality a race between any two "stock" Z28 coupes will come down to driver.
Your statement about race equality between any year model was born out in threads years ago. The OP modified his question and was looking for dyno numbers (which will probably be hard to get at this point).
Registered User
Joined: Mar 2004
Posts: 2,705
in 1996 when the ss came out car and driver had a comparison. A cobra, ss, and ws6. The camaro ran a 13.6@103, the cobra 13.9@100, ta 14.1@100. im not sure how they ran a half second difference with an identical car but they did. I have heard and read about stock cars running 13.50's. Far and few though.
Registered User
Joined: Jun 2005
Posts: 208
So, why does the 95 California emissions 2 cat car rate 275 HP when the 96-97s have 285 if all the difference is in the number of cats? Seems curious. The extra cat obviously was not added for HP gains.
If even the single cat system was restrictive, then adding an aftermarket cat back would produce little, if any, HP gains (but it does add HP). I just can't buy the whole 2 cat extra flow scenario [= HP].
If even the single cat system was restrictive, then adding an aftermarket cat back would produce little, if any, HP gains (but it does add HP). I just can't buy the whole 2 cat extra flow scenario [= HP].
Registered User
Joined: Nov 2005
Posts: 106
Maybe the extra cat helps flow similar to how different length headers will affect flow and thus hp numbers. If a different catback will make any difference in flow at all with the smaller pipe then why would it not be the same for the cats. Idk though its just something to think about.
Registered User
Joined: Feb 2005
Posts: 518
285 vs 275 horsepower
I distinctively remember reading aMotor Trend magazine from 96/97 that had a interview w/John Moss and he said the y pipe was increased to 2.5 from 2 1/4 and that this was a good upgrade for the 93-95 cars and i got similiar results when i installed my 2.75 Borla y-pipe.