Pontiac Firebird 1967-2002 - WS6 vs. Blackbird

what si so damn different? i dont understand...all that i can see is that they have GMMG catback alone...Air lid...and suspension (eibach prokit) and other lil suspension things im assuming....what is there exactly that makes them soooooooo much different stock for stock?...and what do they put down at the wheels....with whatever the mods are

anybody ttt?

go to the gmmg website and you can read about it. They get cooler rims, and the stuff you said, and put down about 380 hp I've heard. They are also very rare and kind of expensive. Top of the line Trans Am. I wish I had one!

http://www.gmmginc.net/html/blackbird.html

Wish I had one too.

im talking engine modifications....not jsut the added stuff....waht gives them that 380 hp?

the 380hp is at the flywheel, which is about the same as a WS.6 with lid + Catback. Its like the difference between a WS.6 and regular T/A, just a few appearence extras.

Lid, Exhaust, emblems, wheels, suspension, and thats about it.

some1 said that they have ported Heads and Manifolds...is that true?

some1 said that they have ported Heads and Manifolds...is that true?

Read the post in this section entitled blackbird and that might help us some.

Call Matt Murphy at GMMG and he will explain it all to you with no guessing.

some1 said that they have ported Heads and Manifolds...is that true?
I dont think so, I was under the impression the only performance stuff it had was lid and catback.

I dont think so, I was under the impression the only performance stuff it had was lid and catback.
If it were that easy to copy than they would not be as rare as they are. :drive:

Just do a search on the web and you will find an article about it. go under trans am with gmmg and you will find an article that tells about everything. :confused:

go to the gmmg website and you can read about it. They get cooler rims, and the stuff you said, and put down about 380 hp I've heard. They are also very rare and kind of expensive. Top of the line Trans Am. I wish I had one!

There were only about 50 made.

the 380hp is at the flywheel, which is about the same as a WS.6 with lid + Catback. Its like the difference between a WS.6 and regular T/A, just a few appearence extras.

Lid, Exhaust, emblems, wheels, suspension, and thats about it.

So, you are saying an air lid (I have a Gigliotti G2) and a catback will give you 380?

the 380hp is at the flywheel, which is about the same as a WS.6 with lid + Catback. Its like the difference between a WS.6 and regular T/A, just a few appearence extras.

Lid, Exhaust, emblems, wheels, suspension, and thats about it.

There are few other differences in a WS6 and a TA than simply the appearance, such as the ram air and the handling.

No you wont get 380 hp with just adding a lid and a catback. My mods in sig and hp and tq.

There's gotta be something else so I'm going to go search.

Theres got to be more to it than that. The Firehawk has more performance options and things done to it than a lid and ram air, and it's not rated for 380HP.

The Firehawk in the 2002 model year built after September 01 were 345HP. So I would bet the Blackbird went up a step from that.

380 HP Blackbirds have larger T-Body ,computer tuning, ported heads and manifolds,underdrive pulleys,air lids ,hi flow cats,and chambered exhaust

All ya had to do was ask .

Dont Forget The Cam...........different Too! Still Curious On Mine ?

Mr Bird Man it looks like you have some pretty bad ass cars.
Props man :cheers:

:drive: Mr Bird Man it looks like you have some pretty bad ass cars.
Props man :cheers:
Thanks man. Love to show them to you if your ever in the New Orleans area. :drive:

:drive:
Thanks man. Love to show them to you if your ever in the New Orleans area. :drive:
How far is that away from Wisner. I visit there a lot.

How far is that away from Wisner. I visit there a lot.
Looks like you about 4 hrs drive south east from were you are in Wisner, if you drive the speed limit. :drive: Any time dude , just give me a heads up.

cool thanks man

The 380 hp rating on the Black Bird is what they make at the crank. My WS6 dynoed 309 at the rear wheels that comes out to 363 at the crank. That was bone stock nothing added and nothing removed. When I dynoed with a Direct Flo lid that put me at 321 at the rear wheels. That made 377 at the crank. With a lid and catback I would have made more than 380. So yes the Black Birds are making that kind of power.

The 380 hp rating on the Black Bird is what they make at the crank. My WS6 dynoed 309 at the rear wheels that comes out to 363 at the crank. That was bone stock nothing added and nothing removed. When I dynoed with a Direct Flo lid that put me at 321 at the rear wheels. That made 377 at the crank. With a lid and catback I would have made more than 380. So yes the Black Birds are making that kind of power.


No offense, but how are you calculating crank versus rear wheel horsepower? The standard I've heard was take your rear wheel and add 15%. By that formula, 309 at the wheels = 355 at the crank. 321 at the wheels = 369 at the crank.

Is there a different formula I should use? If so, that'll make my quest for a big fat 500hp sticker on my car easier.

I take the 309 and divide it by .85. That is how I get 363hp.




No offense, but how are you calculating crank versus rear wheel horsepower? The standard I've heard was take your rear wheel and add 15%. By that formula, 309 at the wheels = 355 at the crank. 321 at the wheels = 369 at the crank.

Is there a different formula I should use? If so, that'll make my quest for a big fat 500hp sticker on my car easier.

Interesting.

Anyone know which formula is the "right one" to use?

Should you take (rwhp / 0.85) = hp
or (rwhp * 0.15) + rwhp = hp

I'd really like to know, since I want to get a nifty little plaque with my hp/tq ratings and I'd like to get pretty close to peak numbers before they engrave.

3.73 rear end also

So... no one has any opinions on calculating RWHP vs. Crank?

So... no one has any opinions on calculating RWHP vs. Crank?
It is just estimating anyway, but theoretically you are loosing 15% of what you made at the flywheel by the time it gets to the wheels. So here is how it figures:
x=FWHP
y=RWHP

x-.15x=y
.85x=y
x=y/.85

So basically WS6 #4541 is correct. Divide your RWHP by .85 (85%) to get your FWHP for an M6. Keep in mind though, that the 15% figure is a guesstimate. To my knowledge, no one has dyno'd one on an engine dyno using the exact components used in the car and then dyno'd it in the car to compare values. Of course even if they did dyno's range in accuracy so the number he came up with would be different on another dyno. I have also heard that dynojet dyno's actually dyno a little high so that factor may be less for them, but for the sake of comparisons, the 15% figure is what most people use.

I just read that Mecham Design has done several tests and found the 3" pipe that come from the factory is fine. The only thing they change is the muffler and ex. tips for sound and looks. I bet the black bird is just programed a little differant, with underdrive pullys.

J Rogers CHICKIN MAN