Captain Apex

I am the proud new owner of a 1990 rx-7....Im not gunna lie, im kinda new to this whole rotory thing, ive done enough theory and teardown of blown rotories to be able to successfully do a rebuilt on mine but i need some insight on wut internals to use.... does ne one have ne reccomendations as to whut rotor and apex seals i should use.... and if there is any real need to get a high preformance crank... or even where to get one? i want to replace them with internals that allow some serious high reving action.... i like that idea and want to know how to go bout it... help me lol

alexdimen

iTrader: (13)

i've only built two engines, but i do have 10k miles of moderately hard driving on my current engine running factory compression and i can tell you what i used.

i got all of my seals, gaskets, and bearings from atkins rotary and replaced *everything* but the oil seal springs. they have held up well so far and i enjoyed dealing with them but like any company there are people who have had bad experiences with them.

first it's an eccentric shaft, not a crank and i've honestly never heard of anyone even considering a custom one for just a near-stocker on the street or auto-x track. the only reason i can think you would need one for would be an very high revving peripheral port engine. the stock shaft is very durable and i have spec'd out a 190k one and a 90k one and they both had like-factory wear on them and no run-out.

besides you're not going to get any more power after a certain rpm unless you have some wild porting and a good standalone ecu and you'll just end up putting undue wear on a nice hand built engine.

Aaron Cake

iTrader: (1)

Factory. There is a discussion in the Archives about which rebuild gasket set is best.

There are a few available if you want to spend several thousand dollars. Not necessary at all.

Why?

Syonyk

And... why again do you want "serious high revving action"? On a daily driver, the porting needed to make power up above 8000 RPM or so is so dramatic that you have a 1500+ RPM idle, and almost no power at all below 4000 RPM.

It's not at all practical to use a 10k RPM engine on the street. Plus, you need special rotating bits that can take the RPM, as well as a scatter shield & such.

-=Russ=-

GTR

iTrader: (6)

I would recommend OEM parts. Cost a little more but you can never go wrong with OEM. Most of the time

Mx6-Rx7 Addict

You really can't go wrong with almost all aftermarket/oem seals on a NA application. Off the top of my head..

Rotary aviation (i think the most inexpensive)
Atkins
Mazda OEM (Id reccomend)
Hurley (don't think people use these too much anymore due to being on the softer side)

If you really want to go all out you could try a set of Ceramic seals, But in a NA application, it really isn't feasable. Keep in mind that the apex seals alone will cost over a grand for ceramic.

Ianetti is a producer of ceramics. There are a couple other companies but i don't remember there names

If you have the money, i would just throw some 2 peice Mazda seals/springs in it.

No need for an aftermarket eccentric shaft.

If you are really worried about running higher rpms and you want a blanket, I'd spend the money to send your whole rotating assembly off to a company to balance them. I think Racing beat offers this service.

While your motor is torn down, you should port the motor to get the best top end out of it. Running higher than stock redline will not create any more power unless you have larger ports.

Hope this helps

Justin

Captain Apex

well this isnt gunna be like a grocery getter, im trying to build myself a seriously high preformance machine.... it its turboed, its a JDM, right hand drive and all that stuff.... i want to rev to 10 grand and run 20+ pounds of boost.... but im prety sure the stock internals wont hold up for very long doing that, wut i need is some ideas as to wut equipment i should go with, or if some things r better than others.... and yeah im in the process or getting race ports... due to that I currently idle at 1200.. lol

Syonyk

See, you should SPECIFY that it's a track car when you post. Most of the "how can I rev my rotyr engine highr?" threads involve people wanting to outrev someone's Honda just for the sake of doing it.

You'll want to race clearance the rotors, get the race bearings, run a higher oil pressure, and probably some other stuff I can't think of right now. However, you still haven't answered why you want to hit 10k RPM - why not be happy with 8k RPM & a somewhat more reliable engine? Insanely high revving rotary engines are generally NA and peripheral ported, because that's the only way to make insane power without a turbo.

-=Russ-=

Aaron Cake

iTrader: (1)

Whatever...Just find a decent shop, write them a $18,000 cheque and be done with it.

You'll need at the minimum:
-rebuilt engine with large bridge/j-port or small peripheral port
-hardened everything
-3 window bearings
-clearanced everything
-balanced everything
-dowling
-large aftermarket turbo (ie. GT45, T70, etc)
-FMIC
-EMS to run it all
-appropriate fuel system
-big injectors (1600cc)
-aftermarket everything (pump, FPR, pulsation damper, filter, lines)
-upgraded rad
-exhaust

And that's just off the top of my head. There are plenty of details missing (like clutch, flywheel that can support 10K, gauges, driveshaft hoop, scatter shield, etc.).

That doesn't even make sense. You can't be in the process of making ports yet have a running engine. And idling at 1200 RPM shows poor tuning or problems for anything that's not a full bridge or peripheral port. Good tuning can get a bridge idling around 1000 RPM, and even large street ports should idle just a little higher then stock.