Does anyone know the OD of the eshaft at the two rotor bearing locatoins? And what are their dimensional tolerances when brand new?



I'm thinking of running rx8 eshaft and rx8 front and rear start gears again. I want to know if I will need to purchase new rotor bearings to achieve the correct clearance between the rotor bearings and eshaft.



Thanks

the rx8 eshaft is the same as the rx7 the only diffrence is it is lighter causing you to have the rotating assembly balanced to your set up.

Thaniks for your opinion. Anyone else have anything accurate or at least "Right" to share?



From what I understand the E-shaft has neutral balance in the engine, just like the flywheel and pressure plate.

From mazdatrix:





These shafts are .6lbs. lighter than the earlier 13B shafts. The main journal diameters are approximately one-half thou smaller, and there is a one-half thou taper in the rear main journal.



Does the rotary journal lands also correspond to a 1 thou smaller diameter than a S5/S6 eshaft?

There are 4 different rx8 shafts, running the lo po ones will gain you pretty much nothing. Running an FC shaft in Rx8 stat gears, gains you well, nothing..

In order for you to make this an enhancment, you need the rx8shaft of the Ho model, the corresponding stat gears, and either the rx8 or FD front stack.

The rx8 is dimensionally similar to the FD shaft, which are staggered bearing designs. In truth most turbo motors power peak is so far below the reasoning for the rx8 stuff, the cost benefit difference really doesnt make it add up.. The RX8 gears arent any stronger than what its in an FC block..

The main thing I guess I was looking at the rx8 stuff was because the rx8 stuff is the same price as the FC stuff.

I totally agree with you, but the nice thing about the rx8 gears in the HO models they have a 10 window bearing, they are brand new, and I got both for $220cnd. The FC or FD Bearings would have cost that much to get pressed in, with the price of the bearings.

the rx8 ho/6port uses the same bearings as the fd, part number wise. rotor and main.



the low output engine uses fc bearings in the stat gears.

Yes it has the multi window bearing needed to feed the needs of the staggered shaft, which the FC doesnt have, so its not really implementing the whole benefit of the bearing/shaft design. The extra oil is needed for the looser tolerance of the outer rear bearing journal , which is wider tolerance to allow for some shaft flex due to flywheel weight and rpm, without wiping out the rear bearing. On the FC setup for rpm, the key to engine life is getting the engine oil pressure up, and flywheel wieght down and a .0005 cut on the e-shaft, thats where I would spend my money, thats whats also the direction I went with my P-port with a 9500 rpm shift point and also my bridged turbo car which I meant to shift at 8500 , but I couldnt always catch the shift fast enough. I read alot that people think that only s5 up and stat gears were hardened, but mazda says that all gears from 85 on were hardened, makes sense, I have never seen a stat gear failure in an s4 turbo and they have the heaviest rotors.



Btw your getting hosed for bearings, I think I pay 11.00 a piece and I own a press.. https://www.nopistons.com/forums/pub...IR#>/smile.gif ..

lol, i might order some bearings.... you're beating mazdausa by like $26 each