GT350 vs. Z/28

[BaylorCorvette]

I posted a video walk through of an actual z28r. Mantella also claimed the z28r made 470hp. That is with the small restriction and a race tuned, 100 Octane LS7. I believe it is the GMP LS7 which is rated at 525hp (crank). With drivetrain losses and the small 80mm Restrictor, I'd say 470 is probably pretty accurate.

I trust Mantella and Stevenson, both said the Camaro was 470 initially.

A 43mm restrictor on the GTS z28 nets 425RWHP. Per IMSA, the PWC GTS class Max output is 400RWHP.

I think you might have heard the 470 hp from a different source? That video you posted with Mantella said the engine is internally stock and rated at 505 hp (which is the stock crank rating),this is at the 2:41 mark of the video. At no point in the video did the number 470 come up. Only hp that was mentioned was the stock 505.

According to that video with Mantella, the only thing that different with the engine is the intake. So without a restrictor this car would be around 450 rwhp. With a restrictor (depending on size) 385 to very low 400's more than likely. A 43mm restrictor is literally cutting the TB size in half, so I would think that would have a fairly large impact on power.

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[BaylorCorvette]

Per the rules:

"Power output ranges from approximately 300-400 wheel hp. Weight varies depending on power output and tire size."

Doesn't sound like 400 rwhp is firm.

 

[thePill]

Per the rules:

"Power output ranges from approximately 300-400 wheel hp. Weight varies depending on power output and tire size."

Doesn't sound like 400 rwhp is firm.

Good lord, yes it's firm, it's been 400RWHP Max since the beginning of PWC.

The z28 doesn't belong in CTSC or GTS...

 

[thePill]

Debate over...

80mm was 470hp and 475tq.

https://scontent-iad3-1.xx.fbcdn.ne...44_1276719851330933206_o.jpg?efg=eyJpIjoidCJ9

The engine gets a rebuild after 2,000 miles, but the internals are all left stock. There’s a series-mandated restrictor behind the throttle body that knocked its power down to 470 hp and 475 ft. lbs. of torque from the stock 505 hp/481 ft. lbs. of torque for Watkins Glen. It’s the same 7.0 liter LS7 as the street car, but in the name of “balance of performance,” the Camaro has to be knocked down a peg to be on an equal playing field with the other cars on site.

 

[02gtnh]

Debate over...

80mm was 470hp and 475tq.

https://scontent-iad3-1.xx.fbcdn.ne...44_1276719851330933206_o.jpg?efg=eyJpIjoidCJ9

Looks even to me. The Boss at 450hp and the Z28 with 470hp with more weight.:shrug:

 

[thePill]

Looks even to me. The Boss at 450hp and the Z28 with 470hp with more weight.:shrug:

Your truly challenged...

CTSC requires competition to use IMSA 100 fuel and a special PCM to run. ALL horsepower figures provided ARE NOT CRANK. IMSA or the SCCA doesn't check crank power. ALL FIGURES PROVIDED are at the wheels.

The actual LS7 used in racing is a 525+hp version, the Boss 302 is also more powerful, around 460hp.

Now, if the z28 was restricted to 470hp with an 80mm restrictor, it would be around 530hp stock on IMSA 100.

The Boss 302, when left unrestricted makes about 400RWHP. Both the 302R and 302S do not exceed the class maximum of 405 in GS and 400 in GTS. It was built specifically for racing.

A stock LS7 would dyno at 450rwhp (about 20 lower) than the LS7.R. The 80mm restriction should only be about 10hp, if that.

The LS7 in SCCA GTS makes 425RWHP with a 43mm restrictor.


The only two things that don't add up is the only two people still trying to convince people the z28 is a victim.

 

[02gtnh]

Your truly challenged...

CTSC requires competition to use IMSA 100 fuel and a special PCM to run. ALL horsepower figures provided ARE NOT CRANK. IMSA or the SCCA doesn't check crank power. ALL FIGURES PROVIDED are at the wheels.

The actual LS7 used in racing is a 525+hp version, the Boss 302 is also more powerful, around 460hp.

Now, if the z28 was restricted to 470hp with an 80mm restrictor, it would be around 530hp stock on IMSA 100.

The Boss 302, when left unrestricted makes about 400RWHP. Both the 302R and 302S do not exceed the class maximum of 405 in GS and 400 in GTS. It was built specifically for racing.

A stock LS7 would dyno at 450rwhp (about 20 lower) than the LS7.R. The 80mm restriction should only be about 10hp, if that.

The LS7 in SCCA GTS makes 425RWHP with a 43mm restrictor.


The only two things that don't add up is the only two people still trying to convince people the z28 is a victim.

Those are not rwhp numbers. The z28 has 505 crank and about 450 rwhp stock. So how is it gaining 20hp with a restrictor?

 

[thePill]

Sorry bud, IMSA and the SCCA only use RWHP.

If the GTS car makes 425rwhp at 43mm then the 80mm is very close to 470RWHP.

We have two distinct regulations and two distinct outputs. We have enough information to use our brains.

There is no 480RWHP Boss 302 especially with a 60mm restrictor. I'd say maybe 408 since the 302R is at 400RWHP.

Which is in fact close to THE CLASS MAXIMUM.

Right now, with a 60mm restrictor, the z28 is probably between 440-450RWHP.

I'm sorry if you don't want to believe that, it hurts I know...

 

[02gtnh]

Sorry bud, IMSA and the SCCA only use RWHP.

If the GTS car makes 425rwhp at 43mm then the 80mm is very close to 470RWHP.

We have two distinct regulations and two distinct outputs. We have enough information to use our brains.

There is no 480RWHP Boss 302 especially with a 60mm restrictor. I'd say maybe 408 since the 302R is at 400RWHP.

Which is in fact close to THE CLASS MAXIMUM.

Right now, with a 60mm restrictor, the z28 is probably between 440-450RWHP.

I'm sorry if you don't want to believe that, it hurts I know...

You are so wrong. Sorry. Those are all crank numbers and take it to the bank.

 

[BaylorCorvette]

Good lord, yes it's firm, it's been 400RWHP Max since the beginning of PWC.

The z28 doesn't belong in CTSC or GTS...

Technically "approximately" is not a finite number. As an engineering company I know we've never used the word "approximately" when discussing a specific number. Now a range +/- from a specific number? Sure.

Debate over...

80mm was 470hp and 475tq.

https://scontent-iad3-1.xx.fbcdn.ne...44_1276719851330933206_o.jpg?efg=eyJpIjoidCJ9

That link you posted is to the Mustang, stating it make ~450 crank hp, not the quote for the Camaro's power.

BUT assuming that quote you posted is legit we're talking crank numbers. It says "a series mandated restrictor knocked its power down to 470 hp from the stock 505 hp"

Those are not rwhp numbers. The z28 has 505 crank and about 450 rwhp stock. So how is it gaining 20hp with a restrictor?

 

[200MPHCOBRA]

You are so wrong. Sorry. Those are all crank numbers and take it to the bank.

So, how bout you tell me where to get one of those 100 wheel horsepower ECU tunes for my Boss.

 

[thePill]

You are so wrong. Sorry. Those are all crank numbers and take it to the bank.

No, there is no way IMSA and SCCA make you engine dyno. All classes are based on RWHP output.

Cry all you want, a restricted LS7 is stronger than a Boss 302 by a decent margin.

 

[02gtnh]

So, how bout you tell me where to get one of those 100 wheel horsepower ECU tunes for my Boss.

What are you talking about?

 

[thePill]

Maybe Chevy should have just tried to make a complaint engine. It would have helped...

I like how an LS7 loses 35hp with an 80mm restrictor while you push the idea that the Boss is a 480hp engine with a 60mm restrictor.

:lol:


How about this, try making an efficient and compliant engine.

I would also like to know how an LS7 makes 425RWHP with a 43mm restrictor while you ASSUME a CTSC LS7 makes FAR LESS with a far smaller restrictor.

Go ahead... I'll wait....

Fact: 425RWHP @ 43mm on 98 Octane
Your Fact: 400RWHP @ 80mm on IMSA 100


Do you see how backwards that is...

and I'm sorry to say, your not going to produce LESS power with a smaller restrictor.

You are WRONG. Stop talking now.

 

[02gtnh]

No, there is no way IMSA and SCCA make you engine dyno. All classes are based on RWHP output.

Cry all you want, a restricted LS7 is stronger than a Boss 302 by a decent margin.

Your the one crying foul. Look at all the other cars hp and then look at there stock hp before you put more egg in your face.

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