my Subaru will beat with a Buick heart!

[Laverne]

interesting, we cryo all our shafts and gear sets. they last a lot longer through the same beating

[Laverne]

Another thing is REM ISF micropolishing. There is actual data (id have to search again for it though) that shows significant increases.

[frank_ster]

and who does this cryo treating ?

[ehsnils]

I would say that the real reason is that it's a tad stronger engine combined with the fact that all torque is put down through the rear diff. A beefed up rear diff would be the thing, but you have to find one. Maybe you should look for one from a mid-sized Japanese pickup truck.

[ClimberDHexMods]

Interested to see what you choose. There are used options on Nasioc classifieds for a lot less than the $1200 price tag.

[BAC5.2]

Why not take an oe carrier and spiders and send them to get cryod. It will be a lot cheaper and much stronger than standard oe stuff. That's more than likely what kaz is doing for the most part

 

Cryo-treatment only has significant benefits when it's a part of the original heat treatment process. Simply dumping parts into liquid nitrogen can improve impact toughness and hardness, but at the cost of forcing the part to become more brittle. That's one of the reasons they do it with tool steels, because an extremely hard tool is going to be stiffer and deflect less under load, the trade off is a brittle tool that fails catestrophically.

 

Micropolishing does work, but the improvement isn't significant. All it does is give uniform surface flatness to all components, so that there is no "minimum" diameter on any one component (which would be the location of failure). Micropolishing would work on a new component, but on a used component where cracks may have already formed, it won't do anything.

 

I've worked with a LOT of gear manufacturers. 9/10 times, aftermarket cryo-treatment has resulted in no change in the frequency of failure. One retailler of STi gearsets told me over the phone that Cryo was the best marketing he could have asked for. Failure rated were the same, but people loved to think that cryo'd gears were going to be stronger. The biggest benefit of a cryo process during manufacturing is exactly what Frank said; an increase in wear resistance.

 

If you were going to break something that wasn't cryo'd, you'll likely break something that is.

[frank_ster]

I would say that the real reason is that it's a tad stronger engine combined with the fact that all torque is put down through the rear diff. A beefed up rear diff would be the thing, but you have to find one. Maybe you should look for one from a mid-sized Japanese pickup truck.

 

i'm quite sure the chipping happened when the car was almost stock. as well to the reason i changed the cv shaft.

 

i'll look on nasioc see what i can find

[ClimberDHexMods]

I'm still a fan of the Ford 8.8 IF THE AXLE SHAFTS AND DRIVE SHAFT can be adapted, but to be realistic it is a waste. Any reputable aftermarket rear R160, or even some OEM helical or clutch type diffs are probably plenty strong to endure the abuse you give.

 

That's funny, Cryo is (from what I can tell) one of the big things IPT offers over a standard rebuild for their race build. Other than that, it's a spring in the valve body, and lathing the 3 main clutch pack pistons down to allow more layers of frictions/steels. Slap it back together with proper tolerances, and it lasts for years of hard driving. Says a lot about how stong the 5eat really is, that the only thing it lacks is firm clutck pack engagement, and a durable center diff.

 

R180 rear would be nice, but you would have to find it in 3.272 ratio, which isn't going to happen from what I've seen.

Edited November 7, 2011 by ClimberD@HexMods

[YourConfused]

Look to the old Z cars for a diff. I ran R180's in my 240 before upgrading to late model R200's . 2100lb car was killing the R180 rear diffs. The R200 found in the later Z31's (I think it was only in the turbo cars) is a stronger housing, about the same as an 8.8 ford, our the auburn in the late model f-bodies. Just an idea. The Z cars that had the lsd R200 diffs had a finned aluminum rear diff housing which made them easy to spot in a junk yard. I remember them to be a clutch type, but my memory is not the best. Edited November 8, 2011 by YourConfused

[BAC5.2]

What was the final drive in them? Could you get a 3.90/4.11/4.44 ring and pinion for them? What about axle splines?

[ClimberDHexMods]

Or 3.272/3.083?

[Alfred_Buchi]

^^^ Clever screen name!

 

Inventor of the turbo incase anyone was wondering.

 

Sorry didn't see this. Thanks man - first person to mention it. I might have come up with something different had I realized everyone would be calling me Alfred, haha.

[NSFW]

What kind of diff did you damage? Was it an R160 or an R180?

 

If 160, then I vote for upgrading to 180 and see how long that lasts. There's STIs running loads of power through those, I think you'd blow an axle before you blew the diff.

[frank_ster]

stock 160

[YourConfused]

reply to posts 1035, 1036, 1038 & 1039 cause I fail at multi quotes! lol

 

 

 

 

I have a 3.90 and a 4.11 and something else that is low numerically but I forgot what it was. I liked running the 3.90 hooked to the T5 from a mustang, good street gears. I couldn't tell you the splines as that was too long ago and I have all that Z stuff in storage for now. All I remember is that the R160 and R180 were interchangable as far as the half shafts (or rear axles) drive shaft flange, &&& (side note) the viscous lsd and ring and pinion from the SVX (I have two of those funky cars) were also swapable.

 

I only used 1 R160 for a few miles when it started to make noise before swapping to the R180. It was a direct swap for me then. When it went crunch I put in the R200, but it required a different mount from a 280 ZXT or the 300ZXT. The R200 also used shorter half shafts because it was wider by a couple of inches, and about an inch longer overall. The R200 used a different diff to axle conection that my memory is fuzzy about though.

 

Anyway sending 350 ftlbs to a single diff is allot different than sending that energy to multiple diffs. So the R180 should be an easy, reliable find and usually for cheap. The ring and pinion from the 2+2 280zx and any automatic Z of that era was the 3.90 I believe. I think that I got the 4.11 gears from a diesel maxima (think it was a 810 or something model), also from the early 80's.

 

Hell, my front calipers were 4 piston ones from a 84-86 land rover that replaced the single piston ones. All the Japanese stuff seems swappable if you look hard enough.

 

It's been over a decade since I played with all this stuff so I may not be 100% on the specs.

Edited November 9, 2011 by YourConfused
I'm we todd did.

[YourConfused]

foot note

 

Most of the reason the drive train failed was due to every mount being solid, steering to rear diff, machined from Al, steel and G10. The tires were the only forgiving portion of the car. The U joints were Spicer heavy duty, lifetime warranty ones mated to oversized custom made drive shafts (from Austin Drive Train) and they would fail every 3K-5K. I ran 255/50/15 BFG R1's fyi.

[ClimberDHexMods]

Frankster can't upgrade to R180 unless someone finds a 3.272 or 3.083 R180 gear/pinion set, which TTBOMK was never made by Subaru.

[ehsnils]

Alternative is to modify the front diff too to get the right gearing. Lower gearing - better acceleration (or more rubber on the road...)

[ClimberDHexMods]

I looked at doing that. It would be a pretty custom diff, but nothing frank_ster can't do. Would require some custom machined parts. Actually, not sure about whether you could get a MT pinion to go in a 5eat... would need to be a 5eat pinion mated to a MT ring gear... nevermind that's not sounding good anymore.

[frank_ster]

^ yea some guy put a 4 eat ring and pinon modified pinion into a 5 mt ..

 

to have 4.56 or what ever gears in his 5 mt ..

 

but if i change gears i would go lower ..

 

3.07

 

but i think if i get another carrier i will be fine .. its only the stupid spider gears that break. soo .. its on the list of to get parts before i start launching again ..

[Max Capacity]

i changed a rear cv shaft , i poped open the diff while i was there ..

 

and the small spider gears have a bunch of chipped teeth.

 

any body can get me a good price on a carrier ? torsen ?

or a whole diff ? there is a junk yard that has one near by whats a fair price ?

 

 

I paid $330 shipped for my R160 back in May of this year. It had 40,000 miles on it. I did a goggle search for a used R160... and found Tunersnation out of FL.

 

Another idea to find out what other diff's and axles, may be usable is to call Leigh or Frank at the Drive Shaft Shop they have a ton of info. They build some strong stuff for the 1000+whp Honda guy's.

 

http://www.driveshaftshop.com/

Edited November 11, 2011 by Max Capacity

[frank_ster]

the cv only had a torn boot at this point i'm looking for either a torsen or similar diff

[frank_ster]

i think a getting the spider gears stronger or different will get the differential good.

i think the general strength of the 160 is fine since i never intend to use slicks.

 

what about a spool (locked diff carrier )

that must be avaliable for wrx's ?

 

and yes i know the handeling differences and there actually welcome to make the car easier to drift

Edited November 12, 2011 by frank_ster
edited to makesence

[frank_ster]

http://www.franavehicles.com/diffsminispools.html

 

 

yay 350$ for a mini spool !!!!! f ya

[paintpollz]

You should bring it to a hillclimb.

In years past, we've had a vw scirocco, with an audi quattro driveline and buick gran national motor. The car has been in the middle east with new owners for the last couple of years, but rumor has it that it's coming back this summer. It has several of our hill records.

 

Fastest car I've ever seen compete.

 

is this okemo?