just got my currie 9" housing and axles last night.i also got the 11" explorer disc brake setup. its a very nice piece. i still have to order a 3rd member but im going to get a strange one through one of my bosses. he is a dealer so i should be able to get a good deal. i have a couple of quetions that i need answered first.

-should i get a locker or a clutch type posi
-what size u-joint should i use(1350/1330/1310)
-witch drive shaft should i get frome spohn(extreme duty or top gun). and will the stock driveshaft length work with the 9"
-are lower control arm relocation brackets really worth it
- and lastly, what gears should i run. i have 373s right now and im pretty happy with them. i was thinking about stepping up to 411s. its mostly a street car but now that i have this rear i want to take it to the track more. keep in mind that i have to drive to the track. thats why im not sure about the 411s.

any other tips or comments would be great. thanks for any help.

here are some pics

 

Looks nice!! I have a Moser, but I'm pretty sure the install will be the same. I had mine installed in a day - and that's without help!

-I'd get a locker (I got the "Tru-Trac")
-I forgot what U-joint it took, but if you search it's here somewhere.
-I'm still running the stock driveshaft on mine
-I don't have LCA relocation brackets, but I've heard they work.
-They have 4.11's for a 9"?? I'm running 3.70's with a 5 speed (had a 3.73 10 bolt) and that's as steep as I want to go for street/strip, but it's personal preference.

Just my opinion. I'm sure there's others...

EDIT: I didn't hear you mention sway bar brackets - your stockers won't fit right w/o modification. I bought the Spohn ones for a 9". And although my stock TQ arm fit, I thought it was a bit flimsy to control the 9".
I had a heck of a time finding an aftermarket that would. You'll need the ones with 2 sets of holes, and you might still have to do some grinding to fit. - Or fork over the 500 bucks for a Spohn one (way too much IMO)...

 

U-joints are a no brainer: if you want bullet proof the 1350's are the only answer, and make sure they are solid with no grease zerk, the hollow tubes/chennels in a greaseable u joint make them weaker

Driveshaft, a nice 3" steel will handle about anything you can throw at it without going completely nutz to which you'd need a parachute/full fire gear/licsence/etc... if you have a shop locally that builds drivetrain parts for OTR trucks keep the money there and have it built, should a problem ever arise you can deal with it locally instead of the phone BS and shipping BS game. and no, the stock lentgh wont work, you will have to get a new one made to spec.

LCA relocation brackets are not necesary unless you'l lower the car quite a bit, since they're main purpose is to bring driveline angles back to where they should be to prevent binding/wheel hop issues. It is a worthwhile investment to upgrade LCA's themselves to a tubular or boxed set-up to eliminate any flex.

If it's 90% street 10% track, stick with a posi/detroit locker set-up since this will release going around corners and not stress your axles. I've run a full spool for the past few years since I cannot gamble with a posi going bad/slipping for racing, and the car has a real bad push when turning a corner since the rear end is locked soild. But this is a mainly race, street drive when I have time car so I live with it.

How tall of a rear tire are you going with? this will play into rear gear ratio. Where is your cams power band? what type of convertor (stall rating) are you using...is it complimenting your cam? The key with gearing is keeping the engine in the power band so you can use what it's making....too high of gearing and your winging it with little effect other than taking away engine life, under gearing and your lugging the motor and not going as fast as you could be.

 

With 582ft lbs get the 1350 ujoints and measure for the driveshaft to be safe as far as the gears what tranny do you have? If its an o/d the 4.11 should be ok I think there is a 3.90 ratio for a 9" Depending on your tire dia the 4.11 would be about 450 rpm more at 65 mph than the 3.73 the 3.90 will only be about 150 rpm more.The locker should be stronger than the clutch type just more noise.The LCA brackets are going to help you hook better by moving your instant center put them in while your doing the rear swap.

 

Hey IHI looks like your car runs pretty good. Are you still using the stock k-member Im looking into a PA Racing one but dont know if its good its cheaper than most of the rest also looking for a tubular x-member for Th350 cant seem to find a lightweight one Ill probably just make one myself. Any info you might have would be great .Thanks

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The stock driveshaft length doesn't work?!?

I guess I'd better find out why mine works.

 

All I did was change a u-joint and the length of the driveshaft worked just fine too. I guess some apps aren't the same.

 

its going to take me a little while to install it. i have to make time to get over to the body shop i used to work at so that i can spray it. then i have to order the 3rd member. then i have to figure out what im going to do for brake lines. i was going to order LCA relocation brackets but i think they wont do that much for me. im still not sure if i want to use a locker or not. i dont know if i want all that noise.

as for the rear suspension, i have the spohn adjustable lower control arms and the spohn adjustable torque arm. the panhard bar is stock though.

as for right now i have the stock T5 it there . thats why the thread title is "almost bullet proof". i think the tires are 25 or 26 inches tall. next time i get tires i want to run something alittle bit taller.

 

The stock T5 with 576HP ....we should take bets on how long that will last !!!! With an O/D tranny your 4.11S should be fine and if you go with a taller tire it will also help. Are you near Englishtown ,AtcoRaceway or Island Dragway .Ive been to all three Atco beeing the fastest. Im working on a 68 chevelle at work that has a currie 9" and had those explorer brakes (we upgraded to 13" baer brakes) but it came with braided ss hoses to some tabs welded to the axle tubes then we just bent up some lines from there.

 

yeah, all my friends are taking bets when that trans goes. island and englishtown are both a little over an hour from me. i think atco is about 2+ hours. so i have never been there. i plan on bringing the car to island when i do go. im going to check the currie website for the ss brake lines. im sure they have something. i bought some brake line yesterday. ill bent them today.

 

I don't have any personal experience with a Truetrac locker, but if they work anything like a Powertrax locker unit, I'd stay away from it unless you're strictly building a race car. The Powertrax unit I ran was really jerky and noisy, and made it miserable to drive on the street. If anyone can chime in on the how the Truetracs work, that'd be interesting to know. If you're mostly street driving though, I'd still recommend one of the higher end clutch style posi units, such as an Eaton with the heavier preload springs or an Auburn pro series. Also, I just bought a Tremec from a guy who was running a 9" in his 86 Iroc and he said he had to have a custom driveshaft made also, and I'm pretty sure he went with 1350 u-joints. I suppose you could buy a Spohn driveshaft if you wanted to spend that much, but you could probably have a custom steel driveshaft made locally for half that price. Just my .02.

 

I find this amusing if nothing else.....
You've already heard from 2 people that run a 9" rear - EvilCartman and myself, and the stock driveshaft length works fine. But I have a Moser, and Evil has a Strange I believe - maybe Currie is diff. from the rest?? With your torque, you'll most likely need to upgrade anyway IMO.

No way I'd run a clutch type posi myself with the kind of power you're talking - unless it's strictly a street tire only car, or you don't mind replacing them occasionally.

I can't tell you how a Tru-trac posi works, but I CAN tell you I have one, and it's no noisier than the stock ten bolt was. The ONLY thing different is that it doesn't un-lock real easy and a rear tire will sometimes squeel when making a sharp right or left. Then again, I don't have many miles on it yet, so it's still breaking in. Detriot makes it, and it's kinds new - should be plenty of info out there on it.

Everything else it as IHI says, he's a wealth of knowledge when it comes to these cars - he just threw me for a loop with the DS length thing...

 

Confuzed: if you guys used the stock shafts then they will fit when rears are the only mod, it's been awhile since I swapped it and I also changed trannies so drivetrain was totally different that stock so I think that is why I had a brain fart and stated that.

regardless, if he wants bullet proof like he stated a new shaft should be the order of the day if stickey tires will be involved at some point since the stockers are thin wall and small, you start throwing some power+stickies+typical weight street car and it will stress the next weak link and the driveshaft would be the next inline....and them things get extremely ugly when they can open your floor boards and whip wildly inside the car....seen 4 cars have that happen and one guy with a dent in his funny car hoop that envelopes the drvier with a dent that went through half the diameter of the bar easily a killer if he did'nt have the funny car addition to the cage and it'd a caught him upside the head and is the main reason I will be installed a rear DS loop before the car comes back out.

Sorry for the mis info on DS length, but from stated above it will work for now, it will just be another department for upgrading.

 

Actually, I'm running a Currie with a center section I got from a local Ford nut hehe.

Mine is also a Tru-trac posi, very smooth operation. Did you soak the clutches before putting it together? If not, it'll chatter and stick. I found that out doing mine but everything seems good now.