I have a new motor with a few thousand miles on it that is streetported with all new parts and competition bearings and grooved water channels. I did not get the rotors clearanced (that's what you do to run higher rpms right?).
What RPM can I safely run? It's still pulling hard when it hits fuel cut at 8K.
I have a PowerFC, I take it my other mods are not really relevant for this discussion.

 

If you are hitting fuel cut, then your least of worries is hitting 9k RPMs. Fix your fuel first. I don't think it's healthy to run to 9k rpms all the time. Maybe every once in awhile for carbon cleaning purposes and not on a stock port 13B for sure.

 

I think he is talking about the rev limiter not fuel cut. He has a PFC so I dont think he would be having boost/fuel cut problems.

 

Yeah I can set the fuel cut wherever I like with the PFC, just wondering if it's going to cause a lot of extra engine wear.
I think the rotors get pushed against the side housings from the e-shaft flexing at high rpms?

 

Wouldn't at some point if no fuel upgrdes were preformed still have fuel cut or does the PFC take care of that and eliminate it all together?

 

I'm running non-seq with 9psi so I'm not running out of fuel... I have 1200 secondaries and a walbro pump to put on before I run more boost.

 

I wouldn't do it daily. I would reserve exceeding 8k rpm for setting up for a certain corner at a racetrack when you just don't quite want to upshift or some circumstance like that.

I think Racing Beat and Mazdatrix recommend to get the engine and flywheel balanced if you are going to be regularly exceeding 8k rpm. Also, even with a streetport, it's probably pointless to rev beyond 8k as the power should start falling off by then -- especially with the stock turbo manifold.

 

Do not do it.

I bet you did not even have your engine dynamically balanced which I condiser a must even for
8000RPMs. Plus as you said, clearancing for rotor to housing and even bearings all have to be done.

 

How does an engine builder "dynamically balance" an engine? I have the bearings.
I have a M2 9.5# flywheel and an ACT Street/Strip clutch.

 

Power used to drop a lot after 7000 but now with the streetport it keeps pulling, I don't know how much it drops off after 8 since I've never tried it. I also have intake, midpipe, catback etc.

 

Best bet is to dyno the car to see where the power drops off. No need to push much beyond that. You're just wasting gas!

 

Yeah as soon as I get all my stuff on I'm going to get it dyno tuned, hopefully someone in San Diego has a Datalogit by then

 

There isnt a point, your powerband is going to be from about 6000-7500. You go past 8K and your way out of your power band. I shift at about 7700 and it drops back to about 6000 or so. Thats pretty much optimal unless you have some crazy porting but you just have a streetport so thats not the case.

STEPHEN

 

I hit 9000+ on my first track day. Of course I should say it was shifting from 3rd to 4th that went into second. I saw the tach comming down through 9000 so I don't know what it hit. I guess no damage because it has taken a year of open tracking and street driving since then an no problems. Thank god there are no valves in there. Aint rotarys grand.

 

Hey thanks guys, I'll keep my redline where it's at.

 

my engine been to 10k rpm. my engine builder judge ito told me as long as the rotors and eshaft were matched from mazda(balanced etc) you can rev to 10k without doing any damage. once you start mix and matching engine parts its not a good idea. that said i have matched rotors and eshaft

 

I wish I had known, the only used part on my engine is one of my rotors. I would have spent a little extra to get it all balanced and matched, does it cost much?

 

What is the average street performance shift if you have a street port two peice two mm motor running on brand new rebuilt stock twins? 7500 garenty that your motor will not have premature damage and how often can you push to 7000 rpms?

thanks joe

 

racing beat can do it. price i have no idea. oh well just rev to 8000 rpm only

 

Mazdatrix balanced my engine for $350 two years ago.

You have to send in your complete e-shaft assembly(that includes everything that attaches to it pemanently). This includes rotors, flywheel, pullies, attaching bolts, keys. They even asked which type of apex seals you will be using. I did all except the clutch as this will be changed periodically and can be balanced seperately.

Engine runs as smooth as an electric motor.

 

I'm in SD and I have one

 

how or where do you get the datalogit?

 

$299 from rx7.com

http://www.rx7.com/cgi-local/3catalog.cgi?cat=11&part=5

 

The engine builder should be the one to set the rpm limit of the motor. Depending apon the street port design, 9k can happen fairly quickly. Ask nocab CJ

BTW: Who did the motor anyways?

 

Larry Scott in Escondido. He said to set the redline at 8K