I have a 72 coupe it came with a 2.0 auto, I have recently put a 4sp in it and just noticed while doing some burn outs in my drive way that both tires spin (nice set of 10 foot marks) (ran out of driveway)
I have the 6.75in rear end
My question is did this car come with posi ??? and if i keep hammering the crap out of it how long will it last ;D
No ,there were no 6 3/4 factory posi units. And, yes, you can thrash the heck out of them and they will last. Now that I said that, A 2.0 will "probably" not brake the rear end. I say that because way back when, I was beating up the stock rear real good behind everything from turbo kits to Nasty N/A motors. The trans, however is a different story.
If my car has posi and it appears to be
what rear end would be in it? It has the cover that bolts on in the rear if the dif.
Has the car sat for a REALLY long time? If so its possible that the spider gears are rusty and dragging enough to get it to lock up. The spiders let the wheel with the least traction spin so its possible that when you have equal traction that both will grab, Ive done it without posi. Rare but doable. Want to see for sure? 2 ways jack up rear and turn one wheel, the other should rotate opposite direction. Other way is put it in a slow hard turn and hammer it, It should just spin the inside tire! Hope this helps.
Yep, and the other thing that old drag racers did way back when was to weld up the spider gears.
It could be a narrowed up 8.8. They had bolts on the rear cover im pretty sure.
The car did sit for a while but that was a few years ago. I will try the spin on a hard turn. (like i need a reason to spin my wheels)
Thanks
Joe
OK
Here is what i got.
I did the sharp turn burn out (lots of fun) and only the inside tire spun, then I jacked it up and if the car is in gear and you spin one tire the other one spins in the opposite direction. if you put it in neutral and spin either wheel the drive shaft turns and the other wheel does not.
If i do a burn out in either forward or reverse it leaves two even tire marks ???
i have a simular problem with my pinto wagon. its a derby car and i wanted to wled the spider gears, but there are non. and if you spin 1 tire the other spins in the same direction but slower. what do i weld for posi?
There has to be spider gears in there somewhere...
It's not hard to get an open diff to act like a posi.on my 73 we used a different spring on one side and unequal lengh traction bars. This will plant the pass side tire first sending the power to the drivers side. when the drivers side bar loads power equalizes and both tires roll.It is possable to do this with just springs
I talked to a guy at a tranny shop and he said both wheels will spin if you have equal traction on both wheels.
I like leaving who tire marks but I think I could really smoke up the street if only one would spin.