FD mods may eventually lead to a focus on the rear end/rear gears. and of course "8.8" emerges as settled science.

maybe.

before taking the XXXXX$ plunge consider that most of the rear end failures (broken diff cases) have occurred due to the fragile spider gears. break the gears, break the case. i don't recall stripped pinions. that's why i run an S6 T2 plate type LSD. out w the spiders, in w the plates. happy OE rear gears.

while i am currently running 600+ i have never done a first gear launch so my trouble free usage should not be necessarily supportive of my suspicion.... that our gears may be fine but our LSD def needs to be changed in many apps.

another very important link to a trouble free driveline is the clutch material. the new ACT Mod Twin ORGANIC sprung double disc is waay easier on the rear gears than any cerametallic disc and that includes the Exedy double.

if i was building another FD i would keep the rear gears, swap out the torsen/spiders and run the ACT organic double.... and save 5+K. my bet is i would have no rear gear problems.

this is just my opinion and i would be very interested in feedback... caveat: i am not saying the 8.8 isn't stronger than our OE gears, rather that OE gears should be fine for most usage with a change in the LSD.

unlike the trans... take the 8.8 money and spend it on a different trans.

 

Ideally, choose a clutch with barely enough torque capacity to hold after a WOT shift into high gear.

Grant

 

Or you could use a Tilton or similar clutch release valve to let it slip a bit on engagement, to soften the hit.

 

One-way orifice style valves like the Tilton leave a lot on the table when compared to a real clutch hit controller...
Here's a link comparing different clutch control devices...
http://grannys.tripod.com/clutchcontrol.html

Grant

 

that’s for dedicated drag racing, the Tilton is well known for street and general motorsports like road racing, autox, etc.

 

Maybe well known, but still leaves standing start reaction time on the table when compared to a real clutch hit controller.

Grant

 

after a bit of searching and coming up w zip i wonder if someone on this board has tuned up their T2 S4 plate type differential.

i recently checked mine... for the first time.

you jack up the rear of the car and turn one of the rear wheels. if it is working the opposite wheel also turns. then, to see if it needs a tune up, you lock one of the rear wheels, put a bar type torque wrench on the axle nut (36 mm) and note the torque at breakaway. my wheel took 25 foot pounds. that's the lower end of O K. from a bit of researching, probably 40 or 50 will work for my needs. serious track mostly is in the 100 neighborhood but you then get chirping around low speed corners.

as many know there are a bunch of friction plates and, i think, a wavy spring that make up the T2 S4 LSD. over time they wear. they also need a fair amount of a specialized friction modifier along w the usual rear end lube.

i would appreciate it, if anyone on our board has rebuilt their Mazda T2 S4 limted slip, might be able to share their expertise.

 

Might want to break out that post into a new thread. Might want to post it in the FC or FD or both forums too. Those are more visited than the Suspension subforum.

I know Goodfellas has done it a long time ago along with the drag racers like Ernie T and such.

 

"Might want to break out that post into a new thread. Might want to post it in the FC or FD or both forums too. "

will do

 

my 4.30 ring and pinon (RX8 auto) is looking a bit shaky ATM... anyone w a 4.1 ring and pinion or carrier under 60 K would be welcomed.

 

found a 36K 4.30. thanks Michael. ordered a Giken LSD and am adding HPPFab diff brace.