Hey everyone. On my current project 65' F100, im looking into dropping some decent power. Looking at a blown 383 stroker, making 650hp or so. The truck will be a weekend cruiser, not a drag racer. Im wondering if the stock OEM ford 9" will be up to the task and hold up to the power? Or will i have to upgrade the rear end with a locker to hold up? Im also looking into doing traction bars to prevent axle wrap. What are your thoughts?

Thanks,
Nick

 

The center section will be fine, but the early 28 spline axles may give up first.

If you can find 31 spines you'd be fine for awhile.

 

Thanks. I figure im not going to be doing any drag racing, no hard transbrake launches and stuff like that, lol.

 

Many moons ago during my first round in performance....the only 2 rear-ends worth their weight were the Ford 9" and the Dana60. It is true about the spline but I have never seen a 9" fail at the track. On the otherside of the coin, I have seen a dozen 12bolt chevy rears fail in a single weekend.

Since you are not racing, then you shouldn't have an issue. But if you are going to have over 600 horses in the stable, my suggestion would be to install new tubs and shorten the rear end. Using the 31 spline axles and shortening the thing will make it virtually bullet-proof.

My guess is with the added horses you're gonna need the extra rubber anyhow.

 

Thanks for the reply. What i was looking for. Guess i'll take it easy on er', until i upgrade, or run it till it breaks then upgrade.

 

Believe it or don't but the very highly modified rears that are run in all of Nascars series today are based on the Ford 9 in.





John

 

There are quite a number of articles comparing the Chevy 12 bolt to the Ford 9"; CarCraft, Muscle Machine Magazine, Chevy High Performance, to name a couple, all basically indicate it's a matter of preference decribing the Chevy 12 bolt as reliable high performance rearend, ideal for a cruiser; however, for those who intend to go for 'off line' torque, durability, and performance the 9" stands out; Chevy Performance described it as 'flogging'.

Went thru back issues of CarCraft Magazine and came across Feb/09 article comparing the 2; fortunately, CarCraft posted article on their tech section of their web page.

12-Bolt Chevy vs. 9-inch Ford: Which is Better?- Car Craft Magazine

Chevy High Performance Magazine also gave the Ford 9" high marks.

9-Inch Vs. 12-Bolt Rearend Compararison - Tech Article - Chevy High Performance Magazine

Back issues of Muscle Machine Mag. are stored somewhere may be on their web page. Anyhow, makes for interesting reading.

 

Until just a couple years ago I had some of my old Car Craft Mags. They were from 1977 thru 1980. I know of many articles in these pages about the comparison of 9" vs 12 Bolt. Just wish we didn't have the limb punch through the shed roof and destroy everything in that box. I would have loved to have some of that info not only for conversations like this but for several things in general.

Quick story about a 12bolt a friend had in his '57. The car was all original sheetmetal including wheel tubs except it did have a tilt glass front end so he didn't want to start cutting it up to put what he really wanted....a shortened 9". The 331 in the car was some serious power. well over 550 horses and that was a lot for 1979. It was a 13 second car and I mean basement 13 seconds in street trim with just the collectors opened up and maybe a tad bit if advance added in. Anyhow he broke seat brackets left and right more than a couple times and that 100.00 bill was never taken off the dash by anyone and I tried more than once or twice and this was just on the street. Once we had it at the track, only had 12" slicks on it and after the third pass, he destroyed the rear end. Sheered all the bolts of the ring gear to the center section just comming out of the bleach box. This happend twice in the same weekend and 3-4 times in the car after that. Since then, I lost my trust in the 12bolt. I know there are hundreds out there that have never had an issue but for me it's the Ford 0" all the way.

 

Thanks for all the info and re insuring info. When time comes, i will pull the rear, make sure its shimmed correctly so it lasts. And if i manage to destroy it, Randy's Ring and pinion sells entire units with the locker built for drag cars, upgrade with that and some axles and i'll be good to go. Thanks again guys for all the info, much appreciated!