9" Ford or 12 Bolt Chevy rear end

[Grumpy]

ok thinkin about moving up the food chain here .. any "opinion's" on these rear ends in a GN

 

[1FASTV6]

ok thinkin about moving up the food chain here .. any "opinion's" on these rear ends in a GN

Is that for the stage car? You can check out Moser Engineering or
Strange Engineering . If you have some coin then check Mark Williams Enterprises- Homepage . If you add up the cost of axles, c-clips, rear and maybe disc brakes you are not far from a complete rear from one of these vendors.

 

[Grumpy]

already have a 9" for the Stage 2 TTA .. This is for Melissa's GN oh I wanted to get it complete .

 

[Quick6'n'-K.C.]

This car isnt too far from me, if i win the auction i could sell the rear to you

eBay Motors: Buick : Grand National (item 320045465217 end time Nov-11-06 11:06:39 PST)

 

[TR Custom Parts]

I remember reading somewhere that the Ford 9" is not as efficient as the 12 bolt. Something to do with the pinion location. I am sure the 9" weighs more as well. That said, my GN had a Currie 9" in it when I bought it with only 4700 miles on the car. Don't know why the original owner went thru that expense with a brand new car?

 

[SVORay]

I read the same thing about the 9" Ford years ago but can't remember much about it. Anyhow, the 9" Ford makes swaping gears easier. If you plan on sticking with the same gears, I would use a 12 bolt.

 

[John Wilde]

The cons on the 9 inch, it weighs more and is a little less efficient.
The pros on the 9 inch, it is stronger, easier to work on and industry standard.
You can be at any track and find 9 inch gears. The 9insh is more scalable IMO.
For example with the 9inch I bought in Chris's car.
It was used behind the 1050HP V-6 and 1833HP V-8 and the only thing we did was put in a spool for safety reasons, since it was out we changed to a 3.7 Gear for more mph.

 

[KEVINS]

9"...If I remember correctly the 12 bolts have slightly different lateral angles than the stock rearends.. They can be bolted in but there is a difference..

ks

 

[T Spool]

I slowed down 2 tenths in the 1/4 when I swapped out the 10 bolt for a 9" in my 79 Z28. The peace of mind was well worth it, no problems with well over 300 passes.

 

[RobsIron]

I read somewhere that there isn't much difference between the 8.5 and a 12 bolt. Mainly just ring size(8.875).

It said a 8.5 is a 12 bolt with a smaller ring gear.

Just what I read. Someone correct me if they know different.

Why not beef the 8.5?

 

[49-blues]

The pinion angle on the 9" is 2" lower than the 12 bolt thereby adding more friction to the 9". mark williams sells a 3rd member that adjusts for this and allows you to run gm 12 bolt gears in a 9" housing correcting the 2" pinion angle for less friction. Strange also sells a S-60 (my next rear) which has a 9.75" ring gear-almost bullet proof for a S2 application I have a 9" in my 84 gn and a strange S-60 is going in my 87 gn.

 

[Louie L.]

been checking out the S60's. They appear to be the best of both worlds.

 

[Ormand]

The Ford weighs 177 lbs, without brakes. The Chevy weighs 185, without brakes. And if you get the aluminum third member for the Ford, it's even lighter. There is a comparison at "Chevy High Performance" that gives these weights, I didn't make them up. The comparison points out that the Chevy uses "2 or 2 percent less power", but that's misleading. A hypoid gear set is about 97 or 98 percent efficient. So it might "use" 20 or 30 hp, IF you have 1,000 hp to the rear wheels. So, the difference between the two gear sets is going to be pretty small. Here's the link:9-Inch Vs. 12-Bolt Rearend Compararison - Tech Article - Chevy High Performance Magazine

 

[turbobuick]

ok thinkin about moving up the food chain here .. any "opinion's" on these rear ends in a GN

Why? You really don't need it. If you insist I would go with the 9" the UC location is MUCH better and really helps the IC and shortens the TQ arm in the suspension.

I maybe stepping up to a lighter one on my S2 car and might be willing to sell mine complete with brakes. Give me a call I left you a message the other day.

 

[DCVING 6]

I helped swap in a dana 60 into a TSM car last year. It went SMOOTH! Pretty beefy, but ya don't have to worry about breaking it.

 

[SVORay]

Strange also sells a S-60 (my next rear) which has a 9.75" ring gear-.

Now is this something kinda like what is in my F150?

 

[VadersV6]

The GN rear end can hold up to mad power with some work. If you're going to go ford, why not just go with a late 90's 8.8? Every V8 ford out there comes stock with this rear end. Theres a huge aftermarket for the 8.8's and they can handle ALOT of power. Plus they're light and use all the latest technology in terms of manufacturing and materials.

 

[Louie L.]

Now is this something kinda like what is in my F150?

Its a hybrid style full rear assembly from Strange. It mimics the Dana 60 rear end .

 

[SVORay]

Its a hybrid style full rear assembly from Strange. It mimics the Dana 60 rear end .

Just so you don't think I'm aruging and being a smart ass, I'm just trying to better understand this info. So did the Dana 60's come stock in trucks like my HD? And if so, Strange built a some what better beefer verison of it? Sorry, I've never really messed around with rear end stuff before...well I did meet Mark Williams once if that counts for much :biggrin:

 

[Grumpy]

The GN rear end can hold up to mad power with some work. If you're going to go ford, why not just go with a late 90's 8.8? Every V8 ford out there comes stock with this rear end. Theres a huge aftermarket for the 8.8's and they can handle ALOT of power. Plus they're light and use all the latest technology in terms of manufacturing and materials.

well I put an 8.8 in the Mazda guess we are staying with the stock rear end ... thanks for the reply's guy's