'87 IROC 5.7 vs '87 GNx
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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
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'87 IROC 5.7 vs '87 GNx
The summer I got my IROC my buddy, Ralph, got himself a Buick Grand Nationalx. One day we headed to the back roads with Dino's '78 TA 6.6, Vince's 71 Supercharged Big Block Camaro and us. The intention was to do some burn outs and take some pictures. Ralph and I were leading the way when we stopped at the end of a long straight stretch to discuss what it was we were going to do. I pulled up alongside Ralph's drivers side and put the window down. Not a word was exchanged. I looked at him, he looked at me, I looked back and before you know it both our feet were on the gas as if there was some sort of mental telepathy involved!!!!
The GN got the jump on me and got about a fender length ahead of me and that's pretty much where he stayed until we got about a quarter mile down the road when.................
The GN got the jump on me and got about a fender length ahead of me and that's pretty much where he stayed until we got about a quarter mile down the road when.................
Last edited by KnottyBuoyz; Jun 16, 2009 at 11:53 AM.
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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: Not sure, gotta look it up
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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: Not sure, gotta look it up
Re: '87 IROC 5.7 vs '87 GNx
) even though they kicked a$$. Member
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From: Toledo ohio
Car: 87 Black Irocz28
Engine: 350 TPI
Transmission: 700r4 shift kit
Axle/Gears: 3:73 richmend axles and eaton gears
Re: '87 IROC 5.7 vs '87 GNx
OK, What about the GNX and the TA that came with the GNX engine. I think it was only the 89 TA that had it. I bet that would be a good race to see.
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From: Diamondhead, MS
Car: 89 20th Ann. TA
Engine: Turbo 3.8 V6
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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: Not sure, gotta look it up
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From: Davison / Troy ,Michigan
Car: 1991 Pontiac Firebird
Engine: 3.8
Transmission: 700r4
Axle/Gears: Dana 60
Re: '87 IROC 5.7 vs '87 GNx
Not really. There really wasn't any huge performance upgrades between the GNX and the 87 GN. Nothing that would change a beat from a normal beat to a massacre. 245hp vs. 276hp. (under rated but those were the factory specs I believe) 30 more hp. meh.
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From: saint cloud,florida
Car: 1986 Iroc z
Engine: 350 tpi
Transmission: 700r4
Axle/Gears: 3.73
Re: '87 IROC 5.7 vs '87 GNx
I will give my 86 iroc to anyone who wants to trade their buick gnx. and ill give them a crisp 100$ bill.
Re: '87 IROC 5.7 vs '87 GNx
Yes really. Most GN's ran mid 14's with the very rare 13.9. The GNX is a mid to low 13 sec car all day. The HP wasn't as important as the suspension difference. If you have seen the two launch in person you would know what I mean. So yes the difference is huge.
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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: Not sure, gotta look it up
Re: '87 IROC 5.7 vs '87 GNx
Ralphie asked me if I wanted another go when I get my project on the road. Problem is he hasn't got it anymore and wants me to have a go with is Viper! Hmmmm? Lemme think about that for a minute.....
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From: Diamondhead, MS
Car: 89 20th Ann. TA
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Transmission: 200 4R
Axle/Gears: 3.27
Re: '87 IROC 5.7 vs '87 GNx
Just like a TTA. That car was a second faster than a 5.7 TPI but only rated 5hp more.
Can't go by factory ratings.
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From: Toledo, Ohio
Car: 91' bird(WS6>>305TBI), 82'Regal
Re: '87 IROC 5.7 vs '87 GNx
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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: Not sure, gotta look it up
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Re: '87 IROC 5.7 vs '87 GNx
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From: Davison / Troy ,Michigan
Car: 1991 Pontiac Firebird
Engine: 3.8
Transmission: 700r4
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Re: '87 IROC 5.7 vs '87 GNx
A high 13 isn't that rare. I've saw plenty of stock gn's knocking out 13 second times. Being a half second faster isn't going to make that big of a visual difference in a street race. That's what I was saying.
Last edited by 91Bird305; Jul 6, 2009 at 09:18 AM.
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From: NYC / Jersey
Car: 1990 Trans Am GTA
Engine: Turbo 305 w/MS2
Transmission: 700R4
Re: '87 IROC 5.7 vs '87 GNx
Originally Posted by TTA 1387
Just like a TTA. That car was a second faster than a 5.7 TPI but only rated 5hp more....

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From: Iroquois, ON
Car: 87 IROC-Z
Engine: 5.7 TPI
Transmission: 700R4
Axle/Gears: Not sure, gotta look it up
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From: NYC / Jersey
Car: 1990 Trans Am GTA
Engine: Turbo 305 w/MS2
Transmission: 700R4
Re: '87 IROC 5.7 vs '87 GNx
Originally Posted by 91Bird305
Being a half second faster isn't going to make that big of a visual difference in a street race....
http://www.youtube.com/watch?v=SHeleRyLST0
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From: Davison / Troy ,Michigan
Car: 1991 Pontiac Firebird
Engine: 3.8
Transmission: 700r4
Axle/Gears: Dana 60
Re: '87 IROC 5.7 vs '87 GNx
well yeah, if one leaves later then the other one with bracket racing, it will look like that. But if they leave at the same time...
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From: NYC / Jersey
Car: 1990 Trans Am GTA
Engine: Turbo 305 w/MS2
Transmission: 700R4
Re: '87 IROC 5.7 vs '87 GNx
Originally Posted by 91Bird305
well yeah, if one leaves later then the other one with bracket racing, it will look like that. But if they leave at the same time...

http://videos.streetfire.net/video/T...LC2_642132.htm
Last edited by Street Lethal; Jul 7, 2009 at 05:44 PM.
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Re: '87 IROC 5.7 vs '87 GNx
A G.N. motor sure would be a nice asset to my 82' Regal. I'm just happy to have my Regal though in the condition she's in. V6 (3.8NA) Pokey but runs really smooth......
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From: NYC / Jersey
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Transmission: 700R4
Re: '87 IROC 5.7 vs '87 GNx
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