Another Myth or is it?

[bhfury]

OK - I think we all have heard the one about why the 1987 GN was the last year they were built, but I have another one for you. I was told "the factory hp rating was 245. In reality is was 425 stock. That buick switched the first two numbers around for emission, insurance and EPA ratings." Anyone ever heard that one???:biggrin: :biggrin: :biggrin:

 

[forcedfedv6]

OK - I think we all have heard the one about why the 1987 GN was the last year they were built, but I have another one for you. I was told "the factory hp rating was 245. In reality is was 425 stock. That buick switched the first two numbers around for emission, insurance and EPA ratings." Anyone ever heard that one???:biggrin: :biggrin: :biggrin:

Go dyno a full stock GN and see if you get 425rwhp. LOL, trust me dude it was 245rwhp from factory..

 

[SGRIM]

Myth!

 

[aminga]

It was only 425 for the twin turbo FBI model

 

[SGRIM]

It was only 425 for the twin turbo FBI model

With factory NAS

 

[whitehot1]

Could it have been this one instead? but it was only rated at 410 hp

http://www.turbobuick.com/forums/at...-garrett-grand-national-demo-car-poster_1.jpg


John :smile:

 

[GNBRETT]

Definately not 425 hp. Maybe slightly better then 245hp but not by much.

 

[SPOOLFOOL2]

Go dyno a full stock GN and see if you get 425rwhp. LOL, trust me dude it was 245rwhp from factory..

Weren't the addvertised numbers crank shaft HP, not rear wheel?

 

[novaderrik]

i've always heard that based on the performance, it was in the range of 300 at the flywheel, with the 245 rating being closer to what was seen at the wheels.
GM has been known to do this in their top of the line cars- Vettes have been putting out close to their flywheel rated power at the wheels for a long time.

 

[SPOOLFOOL2]

Wasn't sure.

Good info. Thanks.

Mike B.

 

[JOHNDEEREGN]

It was only 425 for the twin turbo FBI model

LMAO :biggrin:

 

[Nick Micale]

OK - ...... I have another one for you. I was told "the factory hp rating was 245. In reality is was 425 stock. That buick switched the first two numbers around for emission, insurance and EPA ratings." Anyone ever heard that one???:biggrin: :biggrin: :biggrin:

I am glad you put all those big grins with that "rumor". :smile:

Amazing what some people will say to show how "smart" they are, or not?

The "story" in 1987 about the Buick HP rating of only 245, when it was apparent nothing in then current production could keep up with it, was that they could NOT publish a HP figure more than 250.

Reason for that was the 1987 Corvette was advertised at 250 HP, and was GM's performance leader. The 1986 GN was rated at 240 HP, again 5 less than the Vette.

The showroom stock GN was lucky to get into the 14's, quicker than the Corvette, but as usual, the car magazines hyped it into the 13's by taking liberty with the term "stock".

Since it could easily out perform a Corvette at the drag strip, it was obvious the 245 HP was understated.

As far as emissions, HP had nothing to do with it. As long as the tail pipe values came into compliance, the Feds or state were ok with that.

The insurance companies had no clue about a Grand National [or T-Type/Turbo T] as they were rated as V-6 Regals. Only many years later did they care about the number 7 in the VIN, which was the designation for a turbo car.

The Grand National package was only listed as an option called WE 2.

In mid-1987 the GNX was sold with a HP advertised greater than the Corvette, but there were only 547 of them and they were more expensive that the Chevy.

I am sure your "source" will not believe a word of what I posted, and bet he is not as old as a GN!

 

["Turbo-T"]

It was probably closer to 300 hp crank power on the GN/T-type. No way could I see a 3600 lb car doing low 14's with only 245 hp at the crank.

Do the insurance companies really care about that VIN 7? I mean "it's only a V6...."

 

[Yankee John]

Horsepower after 1971 was rated as "Net" horsepower, meaning that it was the power of the engine on a dyno with full accessories and equipment installed (all emissions, power accessories, and such included). Pre- 1971 horsepower ratings from the factory were "Gross", meaning that it was the engines HP rating on the dyno with no accessories installed.

John

 

[bhfury]

I am glad you put all those big grins with that "rumor". :smile:

Amazing what some people will say to show how "smart" they are, or not?

The "story" in 1987 about the Buick HP rating of only 245, when it was apparent nothing in then current production could keep up with it, was that they could NOT publish a HP figure more than 250.

Reason for that was the 1987 Corvette was advertised at 250 HP, and was GM's performance leader. The 1986 GN was rated at 240 HP, again 5 less than the Vette.

The showroom stock GN was lucky to get into the 14's, quicker than the Corvette, but as usual, the car magazines hyped it into the 13's by taking liberty with the term "stock".

Since it could easily out perform a Corvette at the drag strip, it was obvious the 245 HP was understated.

As far as emissions, HP had nothing to do with it. As long as the tail pipe values came into compliance, the Feds or state were ok with that.

The insurance companies had no clue about a Grand National [or T-Type/Turbo T] as they were rated as V-6 Regals. Only many years later did they care about the number 7 in the VIN, which was the designation for a turbo car.

The Grand National package was only listed as an option called WE 2.

In mid-1987 the GNX was sold with a HP advertised greater than the Corvette, but there were only 547 of them and they were more expensive that the Chevy.

I am sure your "source" will not believe a word of what I posted, and bet he is not as old as a GN!

It was at a car show I (GN) was entered in. It was just some "expert" who was walking by that decided to tell me the "real story" about the GN. How many times have you heard that one before:biggrin: :biggrin: . I've heard all the stories, but I never heard that on.

 

[GNBRETT]

In 1987 Motor Trend listed the Grand National at 3600 lbs. running a 1/4 mile in 13.9 seconds at 100 mph.

100/234= .42
.42 cubed= .074088
.074088 x 3600 lbs = 266 FWHP approx.

 

[turbofish38]

Assuming a bone stock TR could do a 13.9 back in 86-87 than the magic dyno wheel says 275HP.

Okay it was all paper numbers. When the turbo 3.8 was being devolped it needed a transmission. Can't get the power to the wheels with out one,correct? Buick didn't build transmissions but Hydramatic Division did. Hydramatic about keeled over from laughing when Buick said they needed it to hold up to 300 horses and 400 lb ft of torque. A compromise was made. Kind of like a sports figure negotiating a contract. "I'm going to write a number on a piece of paper and you tell me what you think". I've heard more or less that Hydramatic set the torque limit at 350 lb ft as a favor to Buick. Why the 200-4R and not something stronger like the THM700-R4 or even a THM400 that was still being used by Cadillac? Because it would cost to much to make a new case for the THM700-R4 and a new floorpan to clear the 400.

 

[cchilly]

Nick - not starting anything, but the corvette #'s are a little different

86- cast iron head 230hp
86- aluminum head 235hp
87-aluminum head 240hp

My first car I started modding was an 86 aluminum headed one, so I remember the low numbers I had to start out with.

 

[fitz3820]

Isn't it funny how GM's HP ratings for YEARS ended with a 0 or a 5? Always 245 or 350 - not 243 or something... I call shenanigans

 

[Phoff]

Buick was playing games with the Corvette guys...1986 corvette 230...1986 GN 235...1987 corvette 240....1987 GN 245....the GN in 1986 and 1987 really made between 250 and 270 as long as it wasnt 90+ degrees outside and the car was making 13 to 14psi of boost....GM back then rounded its HP numbers....today they have to be certified so you get an exact number.

Pete