Does My 89 Formula 350 have a 9 or 10 bolt?
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Car: 89 FORMULA 350
Engine: 5.7 L98
Transmission: 700R4
Axle/Gears: 9 BOLT/ 3.27 GEARS
Does My 89 Formula 350 have a 9 or 10 bolt?
I dont feel like crawling under the car but I thought that all 89's had the 9 bolt with 3.27 gears. The guy who sold me the car said it was a 10 bolt with 3.23's. But I dont think it was an option in 1989. Could he be right?
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Car: '72 Chevy Nova
Engine: Solid roller 355
Transmission: TH350
Axle/Gears: 8.5" 10-bolt 3.73 Posi
If it's a non G92 car, it's a 9 bolt 2.77. If it's a G92 car it's a 9 bolt with 3.27s.
10 bolts came on non G92 LB9s and all L03/V6 cars.
10 bolts came on non G92 LB9s and all L03/V6 cars.
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Car: 89 FORMULA 350
Engine: 5.7 L98
Transmission: 700R4
Axle/Gears: 9 BOLT/ 3.27 GEARS
Thanks a bunch! I KNOW FOR SURE ITS NOT A 2.73 OR 2.77 AXLE CUZ AT 80 MPH I WAS SPINNING LIKE 2,500 RPM'S. SO I FIGURE IT IS A 9 BOLT WITH A 3.27 BASED ON THE INFO YOU GAVE ME.
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Car: '72 Chevy Nova
Engine: Solid roller 355
Transmission: TH350
Axle/Gears: 8.5" 10-bolt 3.73 Posi
You can also determine rear end ratio (assuming the speedo is calibrated properly) by driving 70 mph in your 1:1 gear (in a 700R4 it's 3rd gear, in a T-5 it's 4 gear) with your foot lightly on the gas keeping load on the motor, but not so much it's accelerating.
Check your RPM at 70 mph in this manner - if it's 2770, you have 2.77s. If it's 3270, you have 3.27s. And so on..
Check your RPM at 70 mph in this manner - if it's 2770, you have 2.77s. If it's 3270, you have 3.27s. And so on..
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Car: 1995 Formula; 1976 Trans Am
Engine: LT1; None
Transmission: T56; None
Originally Posted by urbanhunter44
You can also determine rear end ratio (assuming the speedo is calibrated properly) by driving 70 mph in your 1:1 gear (in a 700R4 it's 3rd gear, in a T-5 it's 4 gear) with your foot lightly on the gas keeping load on the motor, but not so much it's accelerating.
Check your RPM at 70 mph in this manner - if it's 2770, you have 2.77s. If it's 3270, you have 3.27s. And so on..
Check your RPM at 70 mph in this manner - if it's 2770, you have 2.77s. If it's 3270, you have 3.27s. And so on..
Dumb question: will non-stock tire sizes throw off the accuracy of this method i.e. tires that are taller or shorter than stock?
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Car: '72 Chevy Nova
Engine: Solid roller 355
Transmission: TH350
Axle/Gears: 8.5" 10-bolt 3.73 Posi
Yes, they will throw it off a little, but you should still be able to figure it out if you know what ratio you're looking for, i.e. 2.77 or 3.27.
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Location: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
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Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
FROM the factory, ALL FORMULA 350's & LB9/M5 cars have the performance gear, its not an option like on the Trans Am and the Camaro.
Therefore you Should have the 3.27 B&W (9) gear, unless someone swapped the rear.
The B&W axel was used from 1985 - 1989
Therefore you Should have the 3.27 B&W (9) gear, unless someone swapped the rear.
The B&W axel was used from 1985 - 1989
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Car: Formula
Engine: 6.0 LSX
Transmission: 4L60E
Axle/Gears: 9 Bolt 3:27
[QUOTE=urbanhunter44]If it's a non G92 car, it's a 9 bolt 2.77. If it's a G92 car it's a 9 bolt with 3.27s. QUOTE]
Untrue. My NON G92 Formula came with the 3.27's
Untrue. My NON G92 Formula came with the 3.27's
#10
Want proof of your axle ratio without having to rip off the diff cover? Here is how. Oh and sorry you will have to climb under the car and you will need a helper.
1. Put the car in neutral. Chalk the front wheels for safety.
2. Jack up the back of the car on both sides. Use jack stands to be safe.
3. Put a chalk mark on the sidewall of one of the back tires.
4. Climb under the car and turn the drive shaft exactly 1 turn. Watch the rear u-joint for reference.
5. Have your partner count the revolutions of the chalked tire.
Following this method if you had a BW 3.27:1 rear the tire would make 3.27 turns. So if your buddy yells to you under the car that it turned about 3 and a quarter times you know what you've got. Likewise if he said it turned about 2 and 3 quarter times then you've got a 2.77.
1. Put the car in neutral. Chalk the front wheels for safety.
2. Jack up the back of the car on both sides. Use jack stands to be safe.
3. Put a chalk mark on the sidewall of one of the back tires.
4. Climb under the car and turn the drive shaft exactly 1 turn. Watch the rear u-joint for reference.
5. Have your partner count the revolutions of the chalked tire.
Following this method if you had a BW 3.27:1 rear the tire would make 3.27 turns. So if your buddy yells to you under the car that it turned about 3 and a quarter times you know what you've got. Likewise if he said it turned about 2 and 3 quarter times then you've got a 2.77.
Last edited by cdartz; 06-03-2006 at 10:23 PM.
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Car: '72 Chevy Nova
Engine: Solid roller 355
Transmission: TH350
Axle/Gears: 8.5" 10-bolt 3.73 Posi
hmm i didnt know that about formulas. wierd.
I've seen PLENTY of 2.77 non-G92 L98s (infact my best friend has one), but i think they were all camaros.
I've seen PLENTY of 2.77 non-G92 L98s (infact my best friend has one), but i think they were all camaros.
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Car: '90 Trans Am GTA
Engine: LB9
Transmission: 700R4
Axle/Gears: 2.73's
Originally Posted by cdartz
.
4. Climb under the car and turn the drive shaft exactly 1 turn. Watch the rear u-joint for reference.
5. Have your partner count the revolutions of the chalked tire.
4. Climb under the car and turn the drive shaft exactly 1 turn. Watch the rear u-joint for reference.
5. Have your partner count the revolutions of the chalked tire.
Now, you could also count how many times you have to turn the driveshaft in order to turn both tires (at the same time) one revolution.
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