86 and 87 hp/torque ratings

[jurassic five 7]

Hello,

I've hade this question for a while.

Now when looking at specs of the 86 to the 87 TR's, they're differnet. I know people say they're the same motor, but from the factory was it just how the computer was set up or a factory rating BS that made them so differnet?

To what I've read is the 86 was. 235 bhp @ 4400 rpm, 330 ft-lb @ 2400 rpm (depending on the site it seems).

Then the 87 is 245 HP @ 4400 RPM 355 ft-lbs @ 2000 RPM.

Is this the true rating it was (in reality, not from factory)

Was is just chip improvement they did to let the car get 15 psi instead of 12 psi? To deliver more fuel and run smoother?

Please, could anyone clarify the differences in this?

Thank you everyone,

Adam

 

[XLR8]

From what I have read and experienced, the motors are the same and the factory ratings were low - actual HP was higher. If you look at old publications you will see that the HP rating of the TR's was 5 more than the 'Vette. Chevy raised the HP rating in '87 and so did Buick.

 

[Swt_86]

'86 & '87 motors were the same. Like XLR8 said, the hp ratings were tied to the rating of the Corvette. They were probably understated by at least 50 hp. It is my understanding that the chips were the same with the exception of cold idle characteristics and some emissions calibration improvements. I am sure a more knowledgable member will correct me if that is wrong. They both had the same amount of boost (15 lbs.) and nearly identical perfomrmance.

 

[VadersV6]

GM didnt want to undermine the status of their flagship performance car, the corvette. If the vette guys knew that the GN made more power than the vette, they would raise hell. But GM under rated it, making the vette guys happy, and giving the GN guys one hell of a sleeper.

 

[Quick6'n'-K.C.]

Hello,

I've hade this question for a while.

Now when looking at specs of the 86 to the 87 TR's, they're differnet. I know people say they're the same motor, but from the factory was it just how the computer was set up or a factory rating BS that made them so differnet?

To what I've read is the 86 was. 235 bhp @ 4400 rpm, 330 ft-lb @ 2400 rpm (depending on the site it seems).

Then the 87 is 245 HP @ 4400 RPM 355 ft-lbs @ 2000 RPM.

Is this the true rating it was (in reality, not from factory)

Was is just chip improvement they did to let the car get 15 psi instead of 12 psi? To deliver more fuel and run smoother?

Please, could anyone clarify the differences in this?

Thank you everyone,

Adam

Ive owned wayyyy too many turbo buicks, and ive never seen or heard that 86 turbo buicks run 12psi and 87 run 15psi if thats what you were implying in the above statement.
Both run 14.7 psi (1 BAR) and make the same power. Each and every year ive seen quick cars come out from the factory, the horsepower increases 5-15 horses every year there after.
Where did you hear 86 was 12 psi?
BW

 

[83ttypecooled]

model year hp/tq

Hi,
The official mumbo jumbo I've heard on the issue is that different correction factors were used at the dyno for the 87 ratings, no calibration changes were made.You have to remember, by 87 the cat was out of the bag,so to speak. Everybody knew these were bad rides, and sales jumped drastically to prove it. A few extra ponies meant more sales. The Buick guys even postponed the inevitable FWD switch by producing the GN through December of 87! Unheard of, but it was a money maker for Buick and the general.
As far as the 'vettes are concerned, that stuff is probably true; don't kick sand in the top gun's face, or he might kick back,or whine ,or something....

 

[jurassic five 7]

Thank you everyone for giving the proper information. I dont remember where i was told/read they only made 12 psi, maybe it was somethen mentioned and just thought they made it stock

I figured it was GM who underated the motors, but i'm glad i got the 'for sure' on everything.

Thanks,
Adam

 

[madhat]

I've always been told that GNs only pushed 12psi...I thought only the GNX pushed 15! Here is one example(well this thread says 13#):

http://www.turbobuick.com/forums/showthread.php?t=107372

 

[Swt_86]

I've always been told that GNs only pushed 12psi...I thought only the GNX pushed 15!

Nope. I ordered my '86 T-Type in September of 1985 - took delivery in November of 1985 and have had it ever since. It pushed 15# of boost then and still does No idea where some of these stories get started

 

[VadersV6]

My uncle, or godfather...whatever you wanna call him...he bought an 86 turbo T in 86. Duttweiler built it up for him quite a bit, and he even went on to build an N/A V6 super stock drag car with 600hp using kenny's old car. Anyway, his turbo t made 14-15psi from the factory. The whole point was to make 1 bar...14.7psi, and naturally, weather and engine conditions could cause that to vary. Some guy with an 86 who was living at 5000 feet elevation, or had something wrong with his car, was probably pushing 12psi and started a rumor that is still going 20 years later. I still remember reading some hot rod mag back in 1986, and they even said then that the car was designed to push 14.7 stock, and how that would turn the 231 into the equivalent of a 462 big block.

 

[deezdad]

My uncle, or godfather...whatever you wanna call him...he bought an 86 turbo T in 86. Duttweiler built it up for him quite a bit, and he even went on to build an N/A V6 super stock drag car with 600hp using kenny's old car. Anyway, his turbo t made 14-15psi from the factory. The whole point was to make 1 bar...14.7psi, and naturally, weather and engine conditions could cause that to vary. Some guy with an 86 who was living at 5000 feet elevation, or had something wrong with his car, was probably pushing 12psi and started a rumor that is still going 20 years later. I still remember reading some hot rod mag back in 1986, and they even said then that the car was designed to push 14.7 stock, and how that would turn the 231 into the equivalent of a 462 big block.

You mean T-Type...