Question for the racers

[400ex]

I got a 71 1/2 ton with 3.73 open in the rear. Everything on the truck is stock setup expcept for a 400 hp 383. Took it to the local 1/8th mile and ran it on street tires.

Of course no traction. Will the stock 12 bolt and carrier bearing (changed once) handle the strain if I install a posi and run 10.5 slicks?

Thanks for any response.

James

[rage'nrat638]

well ...it will brake sooner or later....
if your going to beat on it......
spend your money once.....
12 bolt truck rear end is not the same as a 12 bolt car rear end.....
the car 12 bolt is much thicker as needed to hold up to the high h.p. of the muscel car's.....trucks .....never had much h.p.

i went with a fad 9"...after i blew the built 12 bolt out......
i spent the money twice

[Longhorn Man]

Although, I have witnessed a 68 with a stock 4.10 geared 12 bolt, it ran 13's most of it's life, was driven fairly hard most it's life, was a daily driver, and the last 2 years of it's life it was a high 12 second truck. (still driven daily) He never had a single problem with the rear. He even bolted on one slick at the track. (yes...just one)
I don't know what he was pushing as far as HP or Torque, but 12's is not exactly easy.

[bigjimzlll]

mine hasnt broke yet...11.01 with 13.5" slicks

[400ex]

Thanks for the responses. I don't have the money saved for a nice unit like in Rage's pic. I guess maybe I'll do the posi first and see how that goes. I'm assuming the carrier should be ok since no one had anything to say about it.

Again thanks for your input.

James

[john@thepier]

thats good info guys. I also am in the process of building a truck for the track,and hope to run in the 12's to start out with and then graduate to 11's and so on.my cosern is how is the launch with the stock set-up.how squirly,etc.and if you could afford a 4-link at which point will it be nessary to weld one in. JOHN

[djracer]

I added a posi to my stock 12 bolt and swapped the3.07's for 3.73's I have been 13.50's so far.


As far as the 4 link goes I know 67 drag truck has been 5.40 eighthmile with trailing arms and coilover shocks!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[Longhorn Man]

John, give the stock set up a chance...it's an awsome set up.

[fast_dev]

12 bolt truck here, i do run a stick however so after breaking an axle and then the carrier i switched to a spool and moser c-clip eliminator axles. best of 12.21 with a 1.7 60 ft.