so i jus got a currie 9 inch rear end for my 87 iroc and i ahve a 700r4 tranny...what kinda driveshaft lenght do i need anythign out there i can use or do i have to get a custom one made....anyone kno....cuz i dont....

 

get a custom one made, for several reasons.
- If you needed a 9", then you need more than any factory shaft will handle
- even if you didn't need the 9", factory shafts really aren't that great
- yes, the factory is the wrong length.
As for the proper length, do a search, people who have done the swap have probably posted the length they used. -OR, do the right thing, install the rear and measure as requested from any driveline company.

I'm not trying to be a d**k, but this has been addressed in almost every post involving a 9" install/swap.

 

well i heard differ, i heard i can use my ls1 shaft that i have and get away with just a rear joint change....im hopin for it...eventually im gettin a 4 inch one...ls1 is good for now....

 

1LE & LS1 dr shaft will work but require end yoke change.

 

Did this a few months ago with a friends '86 thats now got a 9"... you just need a combination joint in the back. I beleive 447 was the P/N

 

You can use the factory shaft if you really want to... just make sure you are not going to have and issues with bind between the rear and tranny anywhere in your suspension travel. I don't know about the 3rd member you have, but there are stock yokes of different lengths for the 9". I ran into that problem on a speedbump. Gear backlash didn't like that very much at all.

 

oko im gonna try to wing it with my ls1 shaft with a joint change...its a currie rear end so i donno what kind of third memeber they used...hope it works out.

 

You should be ok just use the conversion joint, if they used a 1350 yoke. I just did this in my 84 TA and had no problems, but I will be upgrading this winter with torque arm and subframe connectors, so I will put in a stronger driveshaft same time. Should be able to do some launching next summer

 

yeah so rear u joint change to 1350 and my ls1 shaft will be good...i got subframe connectors welded in to the ladder bar bracket and the ladder bars are welded to teh rear...with 4:11 and a locker and my blown motor...i wanna see some show winnin wheels in the air i hope

 

...as I said before, if you need the 9" (sounds like it from your combo) then you need more than a factory ds.