Beef up the rear...need advice.

[Mikie]

Ok guys,
Please tell me what I need to safetly run slicks on the car. Reccomend me a set of axles (part number if you know it)
I have FRPP 3.73 gears , but factory differential. what else needs to be upgraded to hold 3,000-4,000 rpm launches.
The Factory clutch may **** out on the track, but right now Im concentrating on the rear.

Thanks for any info.

 

[02nightmaregt]

Are you wanting a straight up drag setup or DD setup?

 

[Mikie]

Definitely a daily driver with ...say 10 serious track events per year.
Gotta drive it to and from the track back to the house.

Also these are full hoosier slicks, not drag radials or dot slicks.

Thanks

 

[AdRock]

Get a set of 31 spline axles, Moser, Superior. 3 inch studs, and since it's a DD you would most likely be fine with an OEM F150 31 spline diff. Before putting it in have a shop do the mods needed to fit the extra clutches in the diff. Might as well replace all the bearings & seals while you're in there too.

 

[the98stang]

Get a set of 31 spline axles, Moser, Superior. 3 inch studs, and since it's a DD you would most likely be fine with an OEM F150 31 spline diff. Before putting it in have a shop do the mods needed to fit the extra clutches in the diff. Might as well replace all the bearings & seals while you're in there too.

+1

31 axles, FRPP 31 spline diff would be perfectly fine.

 

[bhuff30]

Ironically, slicks are often nicer to driveline parts than drag radials. Drag radials don't have such soft or tall sidewalls as slicks. The distortion of the sidewall absorbs a lot of the shock load which drag radials would otherwise give to your driveline.

The 31 spline upgrade would be nice for reliability, but not mandatory either. Just depends on your launch style, tire choice and transmission type. Heck, my 2.3 is still running a 7.5" open rear end with a 1.797 60' time. It survived this long because the automatic is much nicer and doesn't shock load the driveline the way a clutch drop would.

 

[pony_grrl]

I have Moser 31 splines (# A883153) with a Detroit TruTrac diff (# 913A561) and a T/A girdle ( # TA-1806).

It's a daily, my only car, and I have 0 problems. I've run drag radials for 2 years now and no issues also.

 

[TonyG]

I had my stock 28 spline axles/trackloc for over 200 passes with 28" slicks and 5000-6000 rpm launches, and it held up.

For peace of mind, I just switched over to a 31 spline carrier from Randy S ($169) and Moser axles from Jegs ($250).

 

[Mikie]

Thanks guys..and grrls
Definitely food for thought.

 

[02nightmaregt]

I just got done doing the 31 spline upgrade last week. I got the FRPP 31 spline T-lok, Moser axles, and FRPP3.73's. I'm sure this will be strong enough for a DD that doesn't do TOO much dragging. And like bhuff said about the slicks, they won't be jarring the hell out of you either.

 

[SaleenGT2001]

31 spline axles, auburn pro diff, and c clip elims would do the trick.

thats my set up and it has seen numerous 5000 rpm clutch drops

 

[Mikie]

 

[blubullett]

buyfordracing.com should have both the axles and 31 spline trac loc for good prices.

 

[frey_gt]

31 spline Moser axels, 31 spline diff with restacked clutches and no problems yet.

 

[slayr281]

buyfordracing doesn't seem to have them up in their store, only the rebuild kit. Buy Ford Racing Parts!

However, we stock Ford Racing and Moser 31 splines for some great prices.

 

[Mustang92]

At your power level I'd say 31 spline axles, 3" studs, 03/04 Cobra 31 spline diff or TruTrac, weld axle housing (center section to axle tubes) and weld the torque boxes. Then you should be fine. Not 100% bullet proof (you would need to go spool for that) but that will keep the rear together and prevent you from spinning an axle tube or ripping the rear suspension out. I'd steer clear of anything made by Auburn in a drag racing situation.

Bill

 

[Mikie]

Thanks Bill.

I am invited to go with the SC Cobra club to a track rental on Nov 22 and probably wont have time or cash to get the rear done. I am going to plan on a Tax check to take care of it.
Here is my worry....
I am going to put the full Hoosier slicks on a set of Weld wheels and try to get away with running the factory rear.
Now keep in mind that Im not going to be dumping the clutch at any rpm. I plan on heating up the stickies, pulling up to the line and leaving like I normally do on street tires...just easing it out.
I think I will be ok doing this. What do you think?

I will have my buddy there with his trailer so if something would break, I got a ride home...lol

 

[Shiroelex]

I have Moser 31 splines (# A883153) with a Detroit TruTrac diff (# 913A561) and a T/A girdle ( # TA-1806).

It's a daily, my only car, and I have 0 problems. I've run drag radials for 2 years now and no issues also.

I run essentially the same setup, except I have a Tru-Trac Detroit Locker. I've done numerous 5k clutch dumps on 315/35/17 BFG DR's, and have never heard peep from the rear.

 

[stangJunkie04]

I have a eaton rear dif with strange 31 spline axles and frpp girdle it has held up pretty well at the strip. I run MT et streets and launch pretty hard and it has held up so far. (KNOCK ON WOOD)