trying to get ready for track day, i got an 87 TII differential unit, and a spare 5spd FD differential

unfortunately, the spare FD diff had been sitting out in the junkyard for quite many years, so the before/after pictures will be amazing

FD Diff










ewwww

 

as you can see, FD on left, FC on right, the TII diff assembly is cast iron and is full of clutch discs rather than fancy gear mechanisms

it is noticeably more stout

 

get back to work!

 

Thanks for the pics! It is nice to see them side by side.

 

i am going to try to weigh them once i swap the ring gears

 

clean that parts washer you dirty chicken monkey!


why do I see an iron imprint in the towel? WTF?? Can I buy towels like that?

 

TII Clutch Type LSD



FD Torsen LSD

 

FYI, full rebuild kit for a differential is $160, that includes new races/bearings, seals, and the crush piece

i am only replacing seals, as the bearings are reuseable, the diff is in the oven right now getting some wrinkle black, pics to come

 

ive been thinking about trading with my brother. he has an s4 gtu. . . supposedly it has the lsd in it, but im not sure if theres a difference between that and the tII diff. anybody know?

paul

 

the clearance of the ring gear is crucial for it staying around for more than a month. I think the backlash tolerance on the FD is measured in the thousandths.

Think you'll be ready by Sunday?

Tim

 

yep different.

 

yep different.

 

i'm taking it over to rick engman to set it all back in place

i should have it ready by then, if ray crowe can get me some axle seals, he was all sold out

 

before going into polisher



yes, that's the same differential the next day! sandblasted and powdercoated wrinkle black

 

BEAUTIFUL! Definately on my lest of things to do next.

 

I need a 3.9 gear set and would like the more stout turbo II diff.

Is there a specific year/model FC that has exactly what i need or will I have to use the ring and pinion from a FD with the second gen diff?

 

ring and pinion will be needed, the FC is not useable

 

I just found and paid for a set of 3.9 FD gears.

Should be in the mail.

What year Turbo II rear end should I look for?

 

if you'd read my original post, 87-88

unless you goto a reputable junk yard (www.mazmart.com) or buy new, you are likely to be sold the wrong diff and get burned

 

Also,

what are the advantages and disadvantages of running the Clutch type LSD vs the Torsen LSD.

I should be making over 600ft/lbs of torque.. will that be a problem?

 

I hadn't seen another post by you. Just this one stating that you used an 87 diff. I'm asking because I want to know what will work best, in case there is a preferable year beyond 87.

Thanks

 

goto howstuffworks.com and read up on LSD's, Crispeed has ran over 600ftlbs of torque through his, on slicks, and cut 1.3 60ft times without issue

there are several other threads on this subject if you search-

https://www.rx7club.com/showthread.p...light=tII+diff

https://www.rx7club.com/showthread.p...hreadid=229115

https://www.rx7club.com/showthread.p...hreadid=270066

 

thanks.

 

Crispeed also runs an automatic transmission, IIRC, which is FAR easier on the drivetrain...

 

Thanks jim. that's a good point. I'm not familiar with crispeed's setup.

I'll try this setup and see how long it holds up.

It's more sturdy that the stock diff but a lot less expensive than a Kaaz. Utlimately I'd like do something like an 03 cobra rear end.