TII rotors in N/a block question
 

Question to the rotards.

I have recently taken apart my 90 N/a block, and have it ready to put back together. I wish to put in s5 TII rotors and housings in place of the N/A ones.

My question is: at some point it was brought to my attention that I might have to change a few other internal parts to accomodate this "conversion". I will be running a turbo.

WHAT PARTS DO I NEED TO LOOK INTO REPLACING? WHY?

thanks

thats a lot of work/grinding to get the turbo mannys to work with your na more. if your going to turbo an na run the higher compression rotors for more power its the same amount of work and youll get more power out of it.

why do you want to do thst.. The turbo rotors are lower compression ,so your going to lose ciniderable amount of power. The only plus will be is the turbo II housings so you have a more free flowing exhuast

so your saying use the stock s5 N/A rotors and housing? and and work friom that set up?

You probably don't want the N/A rotors then. The Turbo II rotors are only a downgrade if you plan on keeping it N/A.

Back to your original question...

You need to keep the rotating assembly as a group. I don't think you need to worry about S5 NA vs S5 TII rotors (they're very similar in weight), but you need to match the counterweights & such when swapping S4/S5.

The parts you'll need to make sure you have, in terms of keeping the rotating assembly sane:
Front counterweight
Eccentric shaft (the same across all the FCs)
Rear automatic transmission counterweight (if going with an aftermarket flywheel), OR
Flywheel with built in counterweight.

-=Russ=-

There is not much diff in compression... I'm using N/A rotors on my 91 TII engine, I would just swap the housings... Here you go... This is the compression and weight chart...
hxxp://www.mazdatrix.com/faq/rotorwgt.htm

Remember... You can match A+B, B+C, B+A, but not A+C, letters must be within one up or down... Yes... rotors have letters for a purpose... LOL...

thanks, but honestly, already knew that....

I just needed to know that if you were to put turbo rotors in a motor originally n/a...what other parts "internally" would I have to change? bearings?tationary gears?

The bearings and gears are all the same. If you're looking to make a LOT of power, you might want to consider looking into hardened stationary gears, and race bearings (there's more area for oil to flow... or such - I'm a bit fuzzy on the differences).

-=Russ=-

You should change the oil pump also, the TII one outflows the n/a one, and for good reason. And put on a TII front cover for oil return or drill/tap your n/a one, and make sure you have the oil return baffle/cover thing under the front cover.

And don't forget about oil feed for the turbo, you'll have to compensate for that. You're going to continue running n/a irons from what I can gather? Or are you swapping the rotor housings and end housings (irons) all together?

^ good call. Use the T-II oil pump.

Once you get it all done, it might not be a bad idea to get the rotating assembly re-balanced.