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FE Power Forums => Non-FE Discussion Forum => Topic started by: mn67 on March 12, 2017, 07:27:18 AM

Title: 8 in. rear end
Post by: mn67 on March 12, 2017, 07:27:18 AM
I think I know the answer to this but was wondering if anyone has made an 8 in. work. I am building a 71 Maverick with a 445 FE and C4 trans. The car already has an eight inch rear end. Can these be made to take the torque of an FE? Or should I just scrap it and go with a 9 inch, it would need to be gone through and re-geared anyways.
Title: Re: 8 in. rear end
Post by: rcodecj on March 12, 2017, 10:29:31 AM
Go with the 9 inch.
If you have skinny street tires and no wheel hop you might get by on the street with an automatic, no track use.
Even then I'd be nervous about using an 8 inch behind a 445 FE.
I hope I've talked you  out of using the 8 inch.   ;D
Title: Re: 8 in. rear end
Post by: machoneman on March 12, 2017, 11:04:00 AM
No on the 8".

I'd look at a cheap-to-acquire 8.8".

http://www.hotrod.com/articles/ford-8-8-rear-end/

With very heavy racing use (slicks, actual drag racing) go with the much more expensive 9".
Title: Re: 8 in. rear end
Post by: Rory428 on March 12, 2017, 12:55:51 PM
Sell the Maverick 8" to a street rodder, they love them for some reason. Invest in a good 9", with 31 spline axles (larger if drag racing with slicks in your plans).
Title: Re: 8 in. rear end
Post by: mn67 on March 12, 2017, 01:14:48 PM
That's what I thought,  9 inch it is..
Title: Re: 8 in. rear end
Post by: Falcon67 on March 15, 2017, 09:25:20 AM
A properly set up 8" will live - for a while.  How much a while is a crap shoot.  I know a guy that ran low 11s for 2 years on one before it broke.  We got about 600 passes on some 8" 4:11s before it broke a pinion tooth.  Put in a 9" with a 28 spline spool and the stock axles, got about another 250 passes before shattering an axle.  Replaced all that with Strange 31 spine parts in 2006.  No problems since, car runs 7.2x in the 1/8 pulling the wheels every pass.   I built a 9" for the Falcon in 1999 using Mark Williams 31 spline Masterline axles, Peyton housing with small ends (to fit stock 10" brakes), Richmond 4.56 gear.  It's had everything from 300~500+ HP hitting it, racing regularly - maybe 200+ rounds a year or so - since 2003.  Parts still look nice.  Cost $1650 for me to put it together, have spent $45 for one axle bearing since 1999.
Title: Re: 8 in. rear end
Post by: gdaddy01 on March 15, 2017, 09:38:17 PM
I would say that is a good return on your investment .
Title: Re: 8 in. rear end
Post by: cammerfe on March 18, 2017, 12:43:57 PM
A friend of mine started a project on a '79 turbo Mustang. One of the things he did was to put an 8" rear axle in it to replace the factory stuff. Ultimately, I bought the axle from him and soon thereafter, replaced the 4.60 gears with a more liveable ratio.

I used my '79 turbo Mustang as a test bed for a series I wrote for Super Ford Magazine. By the time I was done, we had changed the draw-through carb factory set-up to use a 45 DCOE side-draft Weber carburetor and put a spray system on it, and put out almost 25 pounds of boost. (I ran methanol with the spray.) It was a bit hard on clutches, a corvetty-eater on the street, and I never had a bit of trouble with the 8" rear. The 8" used the same axles as a 9".

KS
Title: Re: 8 in. rear end
Post by: Rory428 on March 18, 2017, 01:19:08 PM
Lets see, a lightweight FOX Mustang with a 2.3L 4 cylinder, and a built 445  inch FE, in a bigger heavier car, yeah, thats an apples to apples comparision!
When you consider that his stock Maverick 8" likely has 2.80 or 3.00 gears, and no form of limited slip differential , spending a bunch of money to upgrade a weak rear end makes no sense at all to me.
Title: Re: 8 in. rear end
Post by: FElony on March 19, 2017, 03:13:45 PM
For those of you possibly unaware, a full spool for the 8-inch in both 28- and 31-spline flavors is available.  http://www.ebay.com/itm/391543894671