why no porting?
 

ok welp i was just kinda sitting around on the 7 boards and i realized there is alot of powe rto be had by porting, just cuious but why doesn't anyone on here do any kind or street porting or 1/3 bridge porting or anything else like that? if noone can give me a good reason why not to i think i might try it in the future seems like a good alternative to the normal mods that i see here. aparently there is someons with a street port and gained 9% whp gain w/o tuning and is running gayly rich so that seems pretty nice

At least one person has ported there engine, but the gains are unproven. Remeber the Renesis is very different from the previous 13Bs. Renesis is all side ports and this gives the engine a different response to porting.

Another reason I don't think it has been pursued extensively is that porting is very intrusive and we (the rotary community) are still trying to figure out what can be extracted from this engine w/o tearing into the engine. Porting is the last horsepower upgrade that should be attempted since it is so damn intrusive.

Just my thoughts

well like i said previously with just a mild street port some guy on teamfc3s.org did he gained a 9% hp gain W/O tuning that pretty impresive it is running like ubber rich. its just a thought

https://www.rx8club.com/series-i-major-horsepower-upgrades-93/great-renesis-porting-project-45052/

when you've got some time, there's a start...its long. 1000+ posts. enjoy ;)

If I ever need an engine rebuild for my 8, I would go ahead and have a port done, but I dont see the intelligence in tearing my engine out just for a 25-30 hp gain.

First off there isn't much room to port on the housings. The intake ports are just about as large as they can get. The exhaust ports do need some attention but they don't really need to get larger per se. There isn't much room to make them larger. Maybe a little. There is far more to porting than just making them bigger anyways. The most important parts of porting are the transition from port to runner. This is what needs the most attention on the Renesis and prmarily on the exhaust side. From what I have seen from playing with those housings, alot of work needs to be done here but most of it is with the exhaust sleeves and not the ports themselves.

I actually don't want to see bridgeporting on this engine anymore. At one point I did. If you look at the 7 forum, there are alot of people that try to bridge the auxiliary ports only on their 6 port motors. Too bad you'll never find a thread over there where they outperformed a much milder and simpler port. Those guys never learn. It's not to say you can't get nice power if you do a full bridgeport but why mess up the drivability of the car and sacrifice low end and gas mileage (if you can say it has any now!) for a few extra horsepower? For a street engine it's not worth it. There is alot to be done yet on the Renesis without getting into larger porting. The exhaust ports just really need to be cleaned up quite a bit. I feel that we will see some nice things happen with port work but it won't take larger ports to do it. That's the single biggest mistake people make when they build engines. They make things too large and too aggressive for their needs and ignore the runners.

You should have a new ecu, a flywheel, and all the usual bolt-ons long before you ever consider porting.

ok kool thanx rotorygod, like i said it is just a question i'm new to owning a rotary my buddy has a fc and all i know is what i learn from him hes pretty smart on it and he also reccomended not goin full bridge i was just thinkin a bridge of 5-6 and street port on 1-4 but i'm gonna do all the bolt ons and such first i was just thinkin this as a alternative to boost

there was a member of the forum who had some crazy hp gains from porting i think his name was judge ito you may still be able to bring up his threads by using his name but he left and they closed them all it was early on and people wouldnt believe him so he got mad i am pretty sure he bridged the last two ports he had a dyno sheet with 248 rwhp posted

The dyno sheet looked very suspect as he had a dyno chart from an RX-7 that looked very close to the one he posted here. When asked about them, instead of explaining it, he got very mad and defensive. There was also a spot on that chart that jumped up about 10 hp but only for a very narrow range of about 100 rpm or so. He also quoted this number when it was probably a glitch. The chart also peaked power at 6500 rpm. That is not where the Renesis makes it's power. No one believed him. He wouldn't explain himself. He just got all mad and rather than try to discuss the results he showed us, he just decided to leave. If they were real numbers, we wouldn't have had all of these problems. He is on other forums and has also not explained himself over there either. There are also those that just believe him and save him the trouble of explaining it. If it sounds too good to be true, it probably is.

I'm new to the RX8 forum. I'm a member of RX7 club as I own 2 RX7's, an 88 S4 and a 93 TT. I also own an 04 RX8 and I wanted to share my intentions. I'm sending my RX8 up to PFSupercars on September 15th for extensive work. By extensive work, Ray (Head Mechanic/Owner) is going to experiment with the engine. He's going to be installing a custom turbo kit, porting the engine, stand alone ecu, injectors, custom tranny. Ray and I have not sat down and discussed which parts will be used, I'm probably going to see him tomorrow. The car will be with Ray for over 2 months as he does his work, research and seeing what will work with the Renisis engine. As Ray makes progress I'll post results of what he did, dyno numbers (with dyno sheets) I don't know exactly what I'm expecting from the RX8 right now, but it should be very interesting to say the least. So wish me luck and hopefully we can start unlocking the secrets of the Renisis engine.

C.J. "EightMan" Rumpf

That sounds cool. Document everything. That's the best way to learn a new engine.

good luck, let us all know of your progress:)

Eightman1977 what state you located in?

Maryland, about an hour away from PFSupercars.

good luck eightman.

I wish i had the cash and some local experts to do that with as well.. it sounds like fun!

that was me with snoochie's car. we actually ended up doing the aux. bridge on it, but only gained another ~7-8 hp.

3rd and 4th gear pulls were a lot different with the afr's but just for the numbers, stock 4th gear pull was ~150, small sp was ~176, aux bridge was ~184. gains were less in 3rd gear, but peak power was about the same.

and the throttle was only 67% open. i'm still waiting on him to save for the ems so we can lose the drive by wire and tune it better. the idle got a little rough with the aux bridge, but drivability wasn't affected. if we can get rid of closed loop @ idle, it'd be smooth as glass still.

Anyone looked at the intake ports of a 4port motor. With the lack of the tertiary ports I wonder if there's more room for improvement than with the 6port motor.

This may be a huge pipe dream but, I was thinking the problem with porting is that you loose alot of driveablility and the engine has to idle at 2,000 RPM plus no fuel mileage etc........ What I ws thinking is a Peripheral or J port that opens up after 5500RPM on the Renesis. SImilar to the kick in the pants that S2K's get when they switch into vtec. Obviously this is not about cams but about air flow. So in the upper range RPM's the car runs like a ported drag rotary with out sacrificing too much driveability in the lower PRM band. Part of me wants to think that this is possible with the right Engine management and some amazing engeneering. I am just curious if this is even a possibility.

^ that's basically what happened with the aux. bridgeport...more top end without compromising low end.

Would it be possible to engeneer such a port on the Renesis? The way I see it as long as it can be opened and closed with RPM one should loose any driveability. Or would adding a bridge port over complicate engine management? Sorry if I sound like a NOOB. I am just trying to gain information on NA horse power gains. I am aware of the limited gains with the "basic" bolt ons. I am also aware that the turbo kits out there a rerather good with the righ ttunning. Personally think it would be great to do a full NA buildup of the renesis and try to achieve 250-280 whp. Which isn't totally out of the question. Time and money anything is possible.

i'm a firm believer that nothing is impossible, so we'll just say that doing anything like that with the stock computer is improbable...

250+ n/a whp is gonna be pretty hard to get with the side exhaust ports, but i bet you could get it pretty close with the porting, tuning, a good exhaust and intake, and engine management. it sure would be expensive to do it that way, though...

hey guitar would you be interested in possibly doin this again if so how much and what form of engine management would you reccomend. My buddy Vince is on teamfc3s.org and he told me bout you and i've been thinking very hard bout doin the porting PM me with some info and how much you wanna charge i can prolly get the management after xmas and maybe we could work something out

guitarjunkie28 - whats the 28 mean?

I'm thinking about buying a Renesis motor this Winter and send it to you for some R&D. What have you thought about doing and just have not done yet because of lack of metal?

it means 27 people picked that name before me :p
that was back in '97 when i first got the hotmail account. since then, i've just kept it for simplicity--that way i don't have to remember a dozen screen names for all the forums i troll.

one thing i've been thinking of--since the port runners are round is doing actuators for all 6 ports and having a full bridgeport that will pass smog.

that'll take custom intake and exhaust manifolds, full exhaust behind that, ems, etc... nobody wants to spend that kinda money on a "i wonder what would happen if..." idea.

that or the nitanol peripheral sleeve actuation on the intake side. i'd try to hook that up to a stepper motor for true-variable port timing...not just the open/closed actuation that we have now.

i'm full of bullshit ideas for this motor. if you got enough time, money, and spare engines, i'm sure i can get at least one or two of them working good.. :D

moonrover... hit up rotaryheads.com--my number is there and we can talk about your PJ. the pm would probably be too long for me to have the patience to type.