i forgot who it was. i think it's about time for an fc project

 

Mazmart has some

 

cool, i'll call them.
thanks!

 

excuse me for my ignorance, but what is fc?

 

the fc is my favorite (86-91) rx7.

i just talked to paul and harry over there--very cool guys.

 

Awesome, and poke some holes in the side of that motor to see what happens, we all know that exhaust is dying to take the shortest route in to the hot side of a snail.

 

i was actually thinking about a peripheral exhaust port. timing options are limited, though. if i dont' close it late enough, i won't make any power...but if i go for the power, it'll eliminate the whole renesis zero overlap vibe.

maybe i'll keep the big side exhaust and do a small pp..maybe, sotra kinda....i dunno. naw, i'll just hog the side ports out and get them welded up.

 

The zero overlap thing is nice and can produce decent power (Surprisingly so), but the peri is king! It would be interesting to see if someone could devise a way to put a sleeve in the new housings to accomodate the peripheral ports and a way to facillitate blocking off the side exhausts. The problem is the amount of heat there wouldn't be very conducive to it. GSL-SE rotor housings might be part of the solution. The increased overlap would allow the scavenging capability that currently is missing, hence the inability to affect power levels through much exhaust tuning. Maybe the answer is to use the Renesis rotors and some aspect of it's efficient induction system in an FC motor or something.
Maybe I should go home and get some rest. It was a real pleasure chatting with you briefly Dave .
Paul.

 

I wouldn't do both types of exhaust ports. Now you're sacrificing proper exhaust timing for flow. Bad idea. There must be balance. The Renesis still makes more power than any nonturbo engine before with the exception of an all peripheral port race engine. I'd leave it like it is and try to imrove it rather than guess about adding different ports. We still haven't seen full potential from the side ports yet. No need to jump ahead.

 

i'm not...i brainstorm outloud a lot.

this would make a nice aux-bridge opportunity... slap on an fc front cover and use an e6k...workhorse ecu. i think lowering the afr's into the low 14's or even high 13's would really help the idle out quite a bit.

but i'm not looking for a rocketship in this one... ported with 200-230 whp is more than enough. i'd kinda like to shoot for a 30mpg fc.

 

I'm really surprised that you're seeing such an increase in mpg on snoochie's bridgeported engine. Do you guys attribute this to mazda's sacrificing of efficiency in order to meet emissions? or possibly to add reliability?

This engine is capable of more all around as an NA and most definitely as a turbo motor. When you did your first porting, I was absolutely astounded to see an increase in gas mileage.

 

i think the intake porting has nothing to do with it. it's all about opening up the exhaust with the renesis...to the best of my (miniscule) knowledge, anyway.

the aux bridge wasn't enough to change the way it feels while driving, except in the top-end, but it isn't diggin' closed loop idling anymore. it never stalls out, but i may end up putting an rpm switch on it to disconnect the o2 sensor below 2k rpm's just to richen it up slightly.

when i was playing with the cz, as soon as i added a very slight amount of fuel (3-5%), it smoothed right out and idles like glass.

of course, the computer saw it about 2 seconds later and took the gas back out. anyway, we know for sure that running it even very slightly richer just makes it hum, but we need a way to do it without killing the fuel economy--hence my above idea.

 

and why the hell isn't the throttle plate opening up more than 67%???? as soon as we get that settled, we'll strap it back on the dyno and see what it does.

 

ooh ooh!!! i might get to do a renesis powered miata later on this year!! i can't wait for that.

 

Your engine is ported right? Have you tried restricting the intake before the MAF to try to reduce flow? If this lets then throttle go 100% open during WOT, then it may be that with an unrestricted intake, the MAF values are too high and throwing the ECU into saftey mode.

Have you put a scanner on the MAF values can compared to stock to see how much higher (or lower) you are flowing?

 

By the way,
I'm already doing a renesis in a 99 Miata with a motor acquired from Mazmart. I'm hoping to use Motec management and of course ceramic seals courtesy of Dr. Iannetti (Design Ideas) available through Mazda comp. Let me know if you want to collaborate on anything.

 

ceramicseal--if you do it first, i'll definately be picking your brain on it. if i do it first, feel free to do the same.