I'm in the process of deciding on an aftermarket turbo. Part of that equation is my redline. What mod's do I need to extend my usable RPM's? I've heard of the following:[list=a][*]clearancing rotors[*]taper e-shaft[*]locking rotor bearings w/ set screws[*]hardened stationary gears (RB or 3rd gen)[*]3rd gen or RB rear stationary gear bearing[*]increasing oil psi (85 or 115)[*]replace e-shaft check ball and spring w/ weber jets[*]lighter ('89 and up) rotors[/list=a]

2) Are any of these mod's not needed?

3) Which mod's should be done first, and how many rev's will each mod get me?

5) About clearancing the rotors, I can calculate running clearances, what numbers am I looking for? Are we talking about just the thrust surfaces, or the entire rotor face? Assuming I have access to a machine shop, what would I tell them to do?

6) About tapering the e-shaft: How much over how many inches?

7) Do the e-shaft end play numbers matter for high-rpm applications?

Any other suggestions for mods that will net me more RPMs?

My setup: '88 Turbo II, 80k miles, fresh seals & springs, E6k, '89 turbo/manifold, and other mod's. I'm still trying to decide between a street port and a mild b-port. Car is used for track events (road racing). Occasionally I run to the store for bread and milk

Apologies for a zillion questions. Thanks for reading this far. Thanks for any input!

Steve C.

 

For sure, CDEF and H. But I'm sure you're more interested in the others!

Rotor bearings have been the items I've heard most of being destroyed by big rpm. (Besides big boost/big rpm/too much timing munching apex seals like I eat M&M's.... 8-P) I guess there are some 3 window? bearings, essentially have more/bigger grooves for oil.

How high do you want to spin?

I'd like to score some of the scoot needle roller bearings. Anyone have some lucky lotto numbers?

 

What is the need to rev above 8500 rpm's if you are going to be running a turbo?

 

the engine I had built for high boosts and High rpms has the following **** in it.

Hurley 2mm racing 2 piece seals
Type II stationary gears
Deep groove rotor bearings
3 window bearings
110 psi oil pressure regulator
4 extra dowl pins
Jesus Chris thats big street port
"Special" E-shaft

I should be able to go to 10,000 rpms but I am not dumb enough to try that ****.

 

I'm not looking for 10,000+ I'd be happy with 8500 - factory redline on the '88 TII is 7k.

Basically, I need the machining specs for rotor clearancing (and possible the e-shaft tapering, if its needed), and some commentary on which of the mentioned mod's are needed for 8500.

I've purposly excluded stuff like RB's $2200 ea. lightened rotors for obvious reasons.

 

One important mod that most of the RX-7 crowd omits:
have the entire rotating system balanced. Do this even for a 8000 rpm engine. Improves power and engine life.

Mazda Trix did mine for about $300 and the engine is soooo smooth.

I sent in the complete e-shaft assemble. Including rotors and flywheel.

You can also rework the oil passeges around the oil pump and in the rear housing to improve oil flow.

Back in my 12A 1983 RX-7 days, my NA 12-A was faster than any of the local NA 13B cars. Why? Attention to every little detail that affects power and speed.

There are some things the rest of you rotor heads could learn
from the boinger crowd.