I'm building a 8.5" for my 4-speed 71' GTO. At what point do I need to have my axle tubes welded to the housing? I'm at about 380 HP,guessing around 450 ft. lbs. torque out of my 400. I run the car at the track for test and tune on street tires,but MIGHT use slicks sometime in the future. Would an auto trans be any different?
Also what type of weld? MIG,TIG,oxy/acetylene? If I take it in to a shop to be done,anything they need to know/info I need to pass on to them? I'm afraid they might know welding,but not rear ends.
Thanks
At what torque/HP level do axle tubes need welding?
Re: At what torque/HP level do axle tubes need welding?
Good questions Drake...
Welding the tubes when at what power level? - TORQUE. Usually Torque is what is a problem on the axles spinning in the housing. anything over 500ft lbs. under 2500 rpms will be trouble with slicks. This is a general rule. NOT an exact... You could have weak welds that could cause this axle tube to spin in the housing before that level or you could have very good welds and not have any trouble at all.
WELDING!!!!! ----> When you have some one weld the tube a high nickel rod etc is best and a preheat to cherry.... BUT most use a Mig welder and will do the job fine for the performance levels well into the 9 sec range.
WARNING!!!!! of welding. When your rear axle is being welded you must not over heat the tube and REALLY SHOULD NOT HAVE ANY SPRING PRESS ON THE TUBES AS THE AXLE MAY WEEP OR END UP BENDING AND BECOME UNTRUE IN STRAIGHTNESS. PLEASE USE CAUTION !!!!!! AS YOU COULD CAUSE MORE DAMAGE THAN IMPROVEMENT IF DONE WRONG.
So it might be better to remove the rear and have the person welding it use a stitch weld technique to keep the tube cool from over heating and weeping. absolute best way is to use a straight bar in the housing to keep the tube absolutely supported and straight until cooled.
Welding the tubes when at what power level? - TORQUE. Usually Torque is what is a problem on the axles spinning in the housing. anything over 500ft lbs. under 2500 rpms will be trouble with slicks. This is a general rule. NOT an exact... You could have weak welds that could cause this axle tube to spin in the housing before that level or you could have very good welds and not have any trouble at all.
WELDING!!!!! ----> When you have some one weld the tube a high nickel rod etc is best and a preheat to cherry.... BUT most use a Mig welder and will do the job fine for the performance levels well into the 9 sec range.
WARNING!!!!! of welding. When your rear axle is being welded you must not over heat the tube and REALLY SHOULD NOT HAVE ANY SPRING PRESS ON THE TUBES AS THE AXLE MAY WEEP OR END UP BENDING AND BECOME UNTRUE IN STRAIGHTNESS. PLEASE USE CAUTION !!!!!! AS YOU COULD CAUSE MORE DAMAGE THAN IMPROVEMENT IF DONE WRONG.
So it might be better to remove the rear and have the person welding it use a stitch weld technique to keep the tube cool from over heating and weeping. absolute best way is to use a straight bar in the housing to keep the tube absolutely supported and straight until cooled.
J D Race
Re: At what torque/HP level do axle tubes need welding?
Thanks,that is what I was looking for.