Like said. I am doing a rebuild but I would like to increase the redline to 9K rpm. What will I need to do/buy for the rebuild (just concerned with the internal bits at this stage). Is a streetport good enough? Or will I have to go bridge? Do I need race rotor bearings? How about stengthened stationary gears? Rotor clearancing?.........etc.

And is there anyone here running above stock redline? Tells us what you've done.

 

Not to many engine builders want there engines to go 8,500+ let alone 9k. The only engine builder that I know will warrenty a 9k rpm engine is Rob from Pineapple. For one thing I know the oiling system will need to be upgraded along with a pretty large street port. (Ask Nocab about what the idle will be like) Not to mention, a single turbo setup of some sort. Sorry I can't be of much more help. CJ

 

if you can talk to a luis from Dragon Motor Sports. his own Rx-7 was able to rev at 9k.. consistanly. so he could spool that giant fookin turbo of his.

 

9000 grand is nothing...The problem is not the revs but your hp drops depending on the set up..
I used to run my 1 st gen to 10,000 EVERYDAY. I ran it 12,500....The engine lasted 121,000 I had rebuilt it once earlier.

 

 

The stock oil system can handle 9000 rpm if in good condition. Modification does not hurt though. What you need is three other things:

(1) porting and turbos to make it worth going that high,
which means torque/power that go up there. Go to https://www.rx7club.com/forum/showth...hreadid=138618

(2) dynamically balanced engine rotating parts. Should be done even for 8000 rpm engines. Makes them soooo smooth.

(3) some engine part clearances need to be increased.

 

How much does the balancing typically run?

 

Kan runs his bridgeported motor to 9k rpm....the guy actually yelled at me for only shifting at 8k . He'll have to chime in on the details, however--I don't know specifics.

 

You can always contact Bryan at rotorsportsracing.com to check as well. Granted he's not as reputable as Steve Kan, but still he is a great rotary mechanic. Just my .02 though. Laterz.

Zach

 

Balancing cost about $350 at Mazdatrix.

When I rebuilt my own engine, I had Mazdatrix balance it. Had to send them all rotating parts. That is the e-shaft and everthing that bolts to it or fits on it like the rotors. They even ask what type and size apex seals you will be using.

I used a new; oil pump, pump chain, and pressure regulator. I did a little oil system passage cleanup, especially on the front housing. Above 4000rpm, even in summer with 10-30 Royal purple, my pressure is about 110psi.

My engine has stock ports but is non-seq with all the other mods you can think of. I did all of this extra just for the increased reliability and smoothness.