Was out at Thunderhill all day and on the last session my rear end developed a crazy whine on partial throttle.
Its not nearly as loud on WOT or decel.

I have a cusco 2way RS and 4.77 FD that came with the car

the dif probably has about 50K+ on it now so if one of the side bearings is shot or the pinion needs to be adjusted
should I go ahead and have it rebuilt?
Im not sure where to buy a rebuild kit either - seems Kaaz is more popular these days.

thanks for any input - Im not much of a mechanic so sorry if any of these ?s are silly

track day was WAAYYY worth any damage!

cheers!

Rebuild. Weir performance sells a rebuild kit for the rear diff, and he can probably help you with the lsd rebuild. If not try Rhys Millen Racing, EDO Performance, or any other authorized distributor. If all else fails contact cusco usa directly; their customer service is very good.

I'd also grab a solid pinion spacer from weir if you don't already have one.

rad - thanks man.
Ill call them on Monday for some advice.

Were you in the 2-tone hatch or the white coupe? I was in the silver coupe.

Two tone!

I was the one who was trying to fashion a catch-can from
some tube & a crystal geyser bottle (thanks for the suggestion)

I was smoke screening people after turn two

I'm suspecting I munched my pinion spacer on the last session.
Car made it home to SF but I had to wear ear plugs (it was screaming!)


Had a blast even tho I was slow (2:25 best lap)
Stock bluetop with 4:77 FD.

That white coupe was pretty fast!

That guy that gave you the idea and the bottle was some kind of genuis. I was filling my catch can too quickly, so I had to make a secondary out of one of those bottles too. It was nice to meet you. Hopefully we'll see you at more events in the future. I'll be instructing again at GDS12 if you want to come out in Aug.

My quick lap in the morning was 2:20.33. I was on dead tires and it was pretty greasy all day. In the afternoon, I couldn't better a 2:23. Once my tires got over 140 deg, it was like driving in the wet. A 2:25 was a respectable time for how hot it was. I rebuilt my engine last Dec and I have redtop higher compression pistons, so I am probably putting a little more power to the wheel than you, but I'm on 4.3 gearing. The white coupe is F20C powered, so it should have been fast!

Sounds like it's time for a new ring & pinion and a rearend rebuild. You most likely broke a tooth or two on the pinion gear and that's why you suddenly have a howling rearend. Hang on to your wallet.