what rotors and seals would you be using though? Aren't there complications in the type of seals you can use for PPort versus side port configurations?

 

Plain Jane Rx-8 rotors, and Seals. Remember these are just smaller Pport exhaust sleeves, not the same size as Rx-7. This is a very good friend of mine's car who has agreed to be a mule so I expect there to be a learning curve. Got his engine apart late the other night, and have a spare being broken down monday.. Going to start machining housings in about two weeks..

 

I don't mean to be a downer, but you're planning on running high boost, in a high compression engine, with seals that weren't designed for PPorts?

There's a reason why you can't interchange seals between the generations and why mazda used the particular design in the rx8.. Chances are that you are going to run into major problems, but a cool build nonetheless! I wouldn't aim for 400-500 horsepower though...

 

WHOA WHOA WHOA!! BACK UP HERE A MINUTE!

I thought that early rotor couldn't be used with Renesis side plates because the side seal had move outwards by a few mm and that this would cause 86-95 rotors' side seals to hit or catch the port on the side plates....

if this is not the case, then the gas control rings are the only obstacle? who machined yours?

also got my GSL-SE housings ready to put along side my renesis plates :D

 

Ok --would the total exhaust port cross sectional area be the same or what?
why go to all this trouble--just drop a 13 B in?

 

boring......
we rx7er's like to mix and match as much as possible, my renesis plates, 85 GSL-SE housings, and yet to be decided rotors, are going in my 91 vert.... it was common place to use gsl-se housings with 12a irons of the past, for secret sauce hp numbers.

 

we are all rotorheads. you guys with previous gens needs to understand that

 

it's been my experience that there is a learning curve that last an entire platform.

The guys with the rx-2s/3 before the rx-7s came out, are about the same as me, whose learning platform was the rx-7, FC mostly. if you have a platform under you belt, you have a different look at what the new platform will do.

They were putting old school carb'd 12a's and 4 port 13b's in the fc, and ditching the new motor without giving it a fair chance. same as many have done with the rx-8, and the 13Brew. anything you can think of is fair-game.
i'm still wanting to see what a 13b msp with "open after 4k rpm" peri exhaust, AND intake, would do. i just don't want to muck up the only 2 gsl-se housings i have. yet.

MOST new to rotary/rx8 Owners, are slowly working there way up into the world I and several others on this forum have been in for years.

 

A 13b msp with peripheral ports wouldn't be a renesis anymore but comparing it to older engines with lower compression ratios would be neat.
I can tell you that a mix and match NA engine built with renny internals, some intake loving (not only ports related), side exhaust ports welded shut (of course relapped to be smooth) and gsl-se housings plus the usual secret sauce becomes an interesting platform. Leaving 2 of the 4 side exhaust ports open may end up being too much while being NA.
My little hands on experience on such a project was limited by a loud bang and budget constraints though.

Going 100% peripheral you're in 13G parts \ race engine territory. Speaking about "engine" names there becomes a moot point as we all know. Each and every builder has its own way of building a peripheral engine but the results are all pretty close together for the top builders.

 

Can't believe I never hurd of this until know. We're was I at this whole time

 

Probably 40 to 50 thousand miles so far on low compression rotors without a failure.
You are correct that they need gas seals added, Cam from Pettit made my rotors.
As for the side seals, I do not know all that was changed, but my ports were definitely non stock.

Not so sure about the older housings, wouldn't you need a custom exhaust?

 

New 2-1 exhaust (saves weight! lol) and custom engine mount (tricky part).

 

I said the mule engine is going to be run n/a.

I've already had a customer reach 550rwhp on a stock height rx-8 seals, and stock rx-8 rotors..

 

longetivity though?
Two weird question--can the rx8 rotors be "sanded" down to reduce the compression just a tad? I am meaning basically just "sanding" down the ridges making it a smooth surface?
Also why are the rotor faces gently curved? Why couldnt the tips be more concave to help fight the end gas movement?
Yea--I am strange this morning.

 

Why do these threads always turn into a bunch of high school kids having a circle jerk around a Penthouse magazine?


.

 

yea i was weird this morning---nevermind.........
but have you SEEN the latest issue--hot dang!

 

I am sure we have all looked at the same machined area, on the exhaust side of the Reny housings and wished.

 

Fixed

However gsl-se housings are a quicker option and you can port them enough, other 13b housings could work but the orings\seals are on the wrong side there...

 

shut ur pretty mouth boy. i have everything to build my 5 exhaust port motor, except the rotors... and a car to put it in... :D i guess the vert could take yet another turn in the other direction...

 

I thought the only purpose of the third ring was to prevent exhaust contamination into the intake? I don't see a necessary reason to spend all the money to have rotors machined because of a lil more dilution. I have about 10k miles on a 6port renesis with 8.5:1 rotors and a Borg Warner s363 with out any problems.

So just curious as why you machined for them. Maybe I missed something.

 

I was told it was required, then again, I was told it could not be done too, and that if done it would cause flow issues due to the lower compression.

Seems to work, glad to hear it can be done easier.

How much boost are you putting to it and what power are you making?

 

very interested myself.

 

oh really? Do you have dyno graphs? Mods list? What transmission? You reached that amount of power, but did it drive off the dyno afterwards?

I really find it hard to believe to be honest - but I'd love to see what was done and how to get that power from a renesis. Oh and if you really did, your customer has the most powerful renesis in the world.

 

550rwhp was made @ 14psi.

Dyno was not recording for that pull. There is a thread here about car. Car drove away.

 

Pretty crazy how well Renesis flows compared to older rotaries, it seems that zero overlap helps with supposedly restrictive exhaust ports Or is it in the top-end?

Did the fuel flow correlated with measured power? I'm pretty sure it did, otherwise you wouldn't post it with such confidence