Debate 9 bolt or 10 bolt
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Car: 90 Formula 350
Engine: 350
Transmission: 700r4
Axle/Gears: Dana 44 3.54
Debate 9 bolt or 10 bolt
OK lets have a conversation on 9 bolt VS.10 bolt I think 10 bolt is the only way to go, add a 4th gen Torsen unit - no cones to wear out! whats your take on strength? I see it as a moot point 7.6 /7.75
then parts availability the 10 bolt wins that too and its easier to service
I've had a 3.27 9 bolt -never any issues with it, I went back to 10 bolt added 28 spline axles and Torsen no issues with it either, I know you can get factory GM gear sets as low as 4.56 in some Isuzu Pup's and 3.73 are common in S10 4x4s
then parts availability the 10 bolt wins that too and its easier to service
I've had a 3.27 9 bolt -never any issues with it, I went back to 10 bolt added 28 spline axles and Torsen no issues with it either, I know you can get factory GM gear sets as low as 4.56 in some Isuzu Pup's and 3.73 are common in S10 4x4s
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Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: Debate 9 bolt or 10 bolt
Stock for stock the 9-bolt. Ive shredded several ten bolts in the past but my 9 bolt held up to the abuse again and again behind a very strong built 350 in my last car. But..28 spline axles along with the 4th gen Torsen would be the way to go for parts availability if nothing else. Id probably rather have the Torsen.
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Debate 9 bolt or 10 bolt
9 bolt with the diff upgrade..
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Re: Debate 9 bolt or 10 bolt
9 bolt with the Australian Torsen. 10 bolt's have the bearings running directly on the axle. 9 bolt has the higher spline count axles no matter what year it is.
You can find good used gears in a variety of ratios and the 3.70's are available new.
The cone type are garbage on both of them.
Both are frankly a poor choice for really high power but you can abuse the 9 bolt more and the Torsen makes it a good cheap option. Mine has been flawless with the Torsen and 3.70's
GD
You can find good used gears in a variety of ratios and the 3.70's are available new.
The cone type are garbage on both of them.
Both are frankly a poor choice for really high power but you can abuse the 9 bolt more and the Torsen makes it a good cheap option. Mine has been flawless with the Torsen and 3.70's
GD
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Car: 89 Formula
Engine: 383 SBC/HSR
Transmission: 700R4
Axle/Gears: 3.73
Re: Debate 9 bolt or 10 bolt
9bolt for sure. Look at my sig, I raced on it for 20yrs. Posi wore out, but it never broke.
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Re: Debate 9 bolt or 10 bolt
I have had both. For the cost of the parts to change gears on a 9 bolt I can buy 2 or 3 complete 10 bolts with the ratios I want. Also LS1 rear brakes are a bolt on swap for a 10 bolt. That said if your doing hard launches neither one is good. But on a road course either one is good. I just find the 10 cheaper and easier to get parts for..
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Car: 90 Formula 350
Engine: 350
Transmission: 700r4
Axle/Gears: Dana 44 3.54
Re: Debate 9 bolt or 10 bolt
Ok yes I know neither rear will hold up to decent power and traction but for the most part on the street with street tires they work fine I did the other day buy a 9 bolt that was in a 90 formula and it had PBR brakes on it shouldn't these have a splash shield or backing plate on it?
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Debate 9 bolt or 10 bolt
Ok yes I know neither rear will hold up to decent power and traction but for the most part on the street with street tires they work fine I did the other day buy a 9 bolt that was in a 90 formula and it had PBR brakes on it shouldn't these have a splash shield or backing plate on it?
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: Debate 9 bolt or 10 bolt
Pretty sure GU5 is a 3.23 10bolt. So guessing that someone swapped in the 9 bolt from a later 89.
My friend has a 90 formula with a 10 bolt and it's the 2,xxx th car built for 90. (even though it was built in 89)
My friend has a 90 formula with a 10 bolt and it's the 2,xxx th car built for 90. (even though it was built in 89)
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Car: 90 Formula 350
Engine: 350
Transmission: 700r4
Axle/Gears: Dana 44 3.54
Re: Debate 9 bolt or 10 bolt
took my 9 bolt partially apart- did you know carrier caps are retained by 3/8" bolts? no wonder people want support covers on these
10 bolts have 7/16" bolts for carrier caps
10 bolts have 7/16" bolts for carrier caps
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