BDC

I don't have a readout of mass-air numbers or the AFR but I do know the fuel was set to run rich, about 12 flat:1. I didn't tune the car and it's not local. All I did was provide some direction to my guy. I'm working on limited information but I do know it's the same car on the same dyno with the port job being the major change. The other stuff is the intake, exhaust, stuff like that.

I didn't do the TB on this car. I know it's an AEM intake kit thing. The exhaust is header change, full exhaust change from there back to the two tips (which, while the header change may not be a good thing for a street car due to potential for loud noise, the rest of the exhaust to change is a good thing for this car).

I didn't build the engine either. This was done for a forum guy who likes to lurk and keep to himself.

I don't understand the desire for the mass air readings in as much as trying to validate the power output of this motor. The dyno shows it. The porting that I did on the housings, even though I had no idea what the specific numbers would be, pretty much line up with what I suspected would result. The motor starves for air up high and it's really no surprise. It tells me there's enough intake manifold but not enough intake port itself. I think I've got a handle on it now.

B

BDC

Yes on the balancing and yes on port timing.

Edit: I've had a couple of these Rx8 rotating assemblies balanced and even though they're close from the factory they're not spot on. It'd be worth doing with all the stock components (from a known-good factory assembly: front c/w, rotors, crank, and factory flywheel) and ESPECIALLY when putting an aftermarket flywheel on that can have a rear c/w!!!

BDC

Thank you. I think I found the trick that works on these.

BDC

VE of the motor is higher throughout and the lack of falling off up to 9k tells me the porting was able to push the effective redline (with respect to where it would normally peak and then dip) up higher. My guess is it'd go to about 9400rpm or so but I could be wrong.

B

BDC

Got this re-printed graph too.

GeorgeH

iTrader: (2)

So, not tuned, runnnig low 12s - it seems that more power & torque could be found with a good tune - no?

RIWWP

iTrader: (2)

No, he said 'he' didn't tune the car. It's still possible that it was still tuned.

Good to see the clarifications, does look quite awesome.

BDC

It was tuned but I didn't do it. I'm not sure honestly what kind of leaps and bounds would be made with tuning on an NA motor unless the stock computer just fires the spark way too late or something to begin with.

The only thing I really had a hand in was the porting work and a suggestion or two here and there on setup. Otherwise it was done remotely. It's one of those guys who doesn't really do forums. It was just interesting to see the change as he was shocked at the difference and so was I.

B

rx 8speciale

iTrader: (3)

nice numbers, when mine pop ill do some intake porting,

olddragger

iTrader: (3)

and that is a reason I have considered going back to the oem flywheel.
OD

GeorgeH

iTrader: (2)

A good tune certainly can make a difference on a N/A motor - it did on mine, and it wouldn't surprise me to learn it's even more important on a ported motor.

Anyway, I understand what you are trying to show here, and it looks good. I've been told (although others here know much more than I) that you want to shoot for an AFR of about 13 on the Renesis, and if the owner is running about 12, there could be bit more torque waiting to be uncovered.

shadycrew31

iTrader: (6)

Jeff was able to squeeze out 13 whp when he tuned my engine, the stock tune is pretty good but there's always room for improvement.

Charles R. Hill

iTrader: (7)

You sure that did not come from those D-585 coils you are using and the new dwell settings for them?

shadycrew31

iTrader: (6)

Must have been!

Charles R. Hill

iTrader: (7)

You can laugh all you want but we have seen 8-15 additional rwhp from Jeff's tune combined with those coils (with 7-8 of that from the coils, alone, by Jeff's own estimation) and with the new standard of proof required by this thread we can post tons of dyno sheets that would "prove" it.

Good luck in your porting exploits, Brian.

shadycrew31

iTrader: (6)

Sorry about that I thought I was laughing with you. I genuinely thought you were kidding since I've never heard you mention this before.

I don't need to see any proof though, I'll take your word for it!

I hope no one thinks that's what i was looking for when I was asking for more information. I simply just wanted to see more data, not for "proof"...

Brettus

iTrader: (2)

It's your avatar Shady - it's got that look about it .

shadycrew31

iTrader: (6)

I was curious about the side seal clearances becuase i know having tighter clearances and using new internals can have a great effect on the engine. there is a good amount of power found in closing up those side seal tolerances. A little late for that now, oh well!


Time to go find some C cups in a bra and get this thing handled!

RotaryMachineRx

iTrader: (1)

Oh Andy

Chad D.

iTrader: (19)

My engine is pretty solid at 9K+. Not that I always push it that far.
My car doing a burnout at 9400K when I was leaving a shawarma place.
Not that this helps with data or anything for that matter, I think it lightens up the thread.
I have learned that my next engine will be meticulously logged to find the "real" solution (other than turbo) thanks to this thread.
-http://www.youtube.com/watch?v=8_tRMe2ym6g

Charles R. Hill

iTrader: (7)

Sorry to have misinterpreted someone else usng my favorite emoticon.

If I ever have a chance to gather the MAF data I am whining about with my own engine build I will do that and present it to the forum for discussion.

BTW, Rotarygod ported my irons many back in '06 or so and I regret not being able to gather MAF data at that time. Comparing my own torque curves to typical torque curves yielded much the same result as seen here.

One thing I am curious about is whether or not these porting dalliances changes the nature of Mazda's design with regard to the Helmholtz resonance effect.

TeamRX8

iTrader: (25)

this seems appropriate

Razz1

Good Job!

RIWWP

iTrader: (2)

Eric, not sure what is going on, but I keep seeing you post here in iSpy, but nothing is showing in the thread for me

lastphaseofthis

So your porting was only to increase the runner diameter? or did i miss something?