rotarygod

It depends on how small the pipe starts out at. It might go up to 3" or it might only go to 2.5". It really will be affected by how large the primaries are. As far as noise goes, that's what mufflers are for.

patrick_andraste

those were my thoughts, Just the megaphone part of the chamber without the closing cone.
Divide the siamesed port in the center completely and have each rotor's two ports feed to a pipe that starts out about 1.75" and opens to 5" then stays that way for a few feet before entering some sort of resonator or chamber sort of muffler.
the idea is to eliminate backpressure to the point that you create a scavenge and create a vacuum in the chamber before it gets to the intake.
Even with some port overlap the idea is to suck through the intake port. that should create a intake tract vacuum to suck more air in and if velocity gets built it could create a stacking effect to get even more air in.
BUT, Port overlap will create unburnt hydrocarbons into the atmosphere (excess pollution) so for enviromental reasons, no overlap or direct injection into the chamber after the exhaust port closes would be the best solution there.

Back I go into my shop and play with my good old fashioned two strokes.

David_M

The best your going to be able to do short of using mechanical means is to equalize the pressure in the chamber near atmospheric pressure. You can only create areas of lower pressure until the exhaust hits open air and you can't have any area within the exhaust be lower than atmospheric. Simple physics proscribe the limit without a mechanical pump involved somewhere. Secondly, since the renesis internaly scavenges would it be wise to pull the small amount of unburned fuel off the edge of the epitrochoid? I don't want to discourage you in your experimentation but I don't see you getting a vacuum without an external pump. If your reffering to increasing the mechanical vacuum that the engine itself produces there is still a practical limit with regards to proper internal scavenging.

I do think that the edge of the NA envelope is nowhere near being pushed but since this is the first practical no overlap engine I think that everyone ( including Mazda ) is facing a steep learning curve.

rotarygod

Let me fully clarify what I mean by leaving a vacuum in the chamber. It would be more accurate to say I want closer to a vacuum left in the chamber than any traditional currently available setup can give. It is very possible to have a pressure lower than atmospheric in the engine through incredibly good scavenging. It has been done before. There's nothing physics defying about it. You just can't get it without doing so at the expense of something else. The cleaner I can leave that chamber and the lower the pressure I can get in it, be it atmospheric, above, below or otherwise, the more power the engine will make everywhere.

Richard Paul

iTrader: (5)

That is correct RG. The word vacuum indicates a total lack of pressure. We use it incorectly. But to get a low pressure area is most certainly possable. Partial vacuum might be a phrase but a pain in the *** to write all the time.

The problem you have Fred is that they expect you to be perfect all the time. You no longer have any slack. Price you pay buddy.

As told by our resident 2 stroker getting the exhaust to work for us is done all the time. It is a pain in the butt to get right but that's why it's an art. One can get a good start on the art of it by reading the book "Intake and Exhaust" by Smith.
This is a British publication and I belive has been up dated since my copy was writen. As have most of my text. Damn I'm getting old.

Speaking of that I got my new copy of Ricardo and while I will comment on it later there is something of note. I never read a book starting at the front and rarely have ever read a "Foward". For some reason I did this one and this was my bible years ago and never saw it but Sir Harry made note of the rotary in his foward, saying that maybe it would be the next breakthrough. I'll have to get it and give you guys the direct quote. This is like God validating your engine.

Nemesis8

iTrader: (3)

Bump-a-t-bump

When you ported, did you change this edge any that Mazda is talking about in this pic?

rotarygod

In that picture, the left side of the port can't be changed as a corner seal would fall in. I could be backcut though to smoothen out the runner to port transition. The right side can't change because it would cross an oil seal track. Only the top and bottom edges can change. If the casting thickness is as it shows in that picture, you can't go up very much at all.

Nemesis8

iTrader: (3)

That's an image from the Mazda Press Release, so who knows if it is accurate for casting thickness. I thought it was interesting to read about that shot of high pressure air.

TrackAddict

Really curious as to the status of this project. Any more tuning done? What about the interceptor as a way to unleash the power this porting was going to deliver?
Thanks!

Nemesis8

iTrader: (3)

I read where the inserts in the exhaust ports speed start up of the catalytic converter. What does this mean? Do they transfer heat or something?

Nemesis8

iTrader: (3)

I found this bit of info:

"The anti-wet port is a bulge cast into the primary intake port of the intermediate housing. It works with the jet air nozzle to create air fuel mixing and atomization. This increases air flow and fuel efficiency at low RPM."

burnoutking999

i'm baaaaccckk!! Its been a few months since i came here. i am recently in a position(soon) to get an rx8. Is snoochies car any further than what is posted a few pages back? if not and time/ money is the issue i would look into it. however i plan i=on going FI and in a bigger way so whatever i do would have to compliment that. i remember that it was a NA project first and then FI possibilities later... am i right. I am interested in seeing what is going on lately.

SomeGuy_sg

Any up dates on the porting process ?

guitarjunkie28

never got to do the ems in snoochies car.

gh0st

OK.... it took me 2 days but i just read through this whole thread starting from day 1.

guitarjunkie- from what i understand, the second time you ported snoochis car, you didnt bridge port it like you wanted to right? you just cut through the water jacket. how is that holding up? how close where you the first time from punching through?

there was a post that said he got the canzoomer, then in the last post you said you guys never got to tune it. has that changed since then?

RG- did you ever persue porting the renesis and flow testing? i know you were more interested in keeping things the same size and against breaking through the water jacket. do you still take that stance on these issues?

also did you ever finish your true dual exhaust system/header/sleeve idea?
----------------------------------------------------------------------------------------------


sorry for all the questions. there is just soo much info in this thread! its been a while since the snoochi porting day, what have we learned since? im still waiting on snoochi to lean out his mix a bit.

rotarygod

Unfortunately the engine I thought I was getting back then, never panned out like I thought so no I've done nothing. It's still just on a list of things I'd like to do. I am trying to get Dave (guitarjunkie) to send me an intermediate housing so I can at least get that project started (hint, hint!!!).

guitarjunkie28

you hint one more time and i'm gonna epoxy that corner and use it myself
but since we're on the subject, i did find it and pulled it off the shelf this morning. i'll find a box and ship it out...just be patient with me.


ghost--
the best we could manage in a 4th gear pull was 185 whp with the canzoomer, but the afr's never steadied out in the low-mid 13's, like i wanted. even so, it only pulled 150~someodd in 4th gear stock, so it's a substantial improvement.

the water jacket stuff i think you're a little confused on. the aux. ports have a secondary bridge to them, but i didn't go through the water jacket there. it was the exhaust i went through the water jackets on, then had welded up. i haven't talked to snoochie in a while, but i saw him a couple months ago on the 210, so makes me believe it's still rollin'. i'm sure i would have got a phonecall if it wasn't, anyway.

this whole project was pretty much cancelled due to lack of funding for an ems.

i've got a ported engine, interceptor, and modified greedy turbo kit i'm going to toss in my fc and have some fun with. i think i'll put it in n/a style to get some factual ported engine numbers, since i never got the results i was looking for.

after i have some n/a fun, i'll go ahead and put that turbo on and have some more fun with the car. i don't think the porting will increase the turbo engine's power output significantly, since the turbo is the limiting factor, but i do believe it'll spool the thing up quicker and have a bit broader power curve.

after all that's done, i want to get rid of the 6-port engine and use a 4-port for the turbo. i think the turbo will like the port timing of that one better.

rotarygod

LOL!

Are you still interested in that 36-1 wheel?

lukky-1

hey,
i'm new to this site & have some rx8 mod questions if anyone is willing to help out.
thanks

guitarjunkie28

gimme gimme!


lukky-1
wuzzup?

lukky-1

i'm looking at a 04 rx8. i drove the car & like it except feel it should have more power. are there turbo kits available for the car that are somewhat easy to install, with fuel & spark management, an external wastegate, that is not too dificult to set up? also reliable?

gh0st

hehe.. sorry for the misunderstanding. i knew going through the water jacket was just on the inside corner of the exhaust port. i just worded my question funny because i asked about the bridge port idea (not sure if you did it yet) and the concerns about breaking the water jacket (the exhaust port) at the same time.

i guess snoochi never got an exhaust/midpipe or header. thats too bad. going from 156 to 185 is huge for the amount of porting done. did you have numbers from the first port untuned ( i think it was 170 or so) to the larger port untuned? in short, did the additional gain from the second attempt come from the canzoomer tuning or the actual enlarging of the exhaust ports?

if i can find a used canzoomer, i wouldnt mind getting a small bridge port done just for the sound and for the persute of knowlage. my only concern would be how drastic the flow path in the motor would be affected. heaven forbid if i decrease up atomization.

gh0st

easy buddy. he addmited hes new so lets welcome him before you chew his head off.

Lukky- welcome to this board. to answer your question, the greddy kit is the most popular kit due it being the only kit availible up until only recently. its cheap and is pretty much bolt on so intallation is easy from what ive seen IMO (some would disagree). keep in mind though, you get what you pay for with this kit so dont expect fuel or spark upgrades.

if your looking for the whole enchilada, id recomend looking up mazsport in the vendor section.

for now, please keep these questions off this thread. the reason i love this thread is becuase its managed to continue for 70+ pages WITHOUT STRAYING OFF TOPIC. Keef is right though, most your questions will be answered by using the search function provided to you. PM me if you have any more questions.

guitarjunkie28

that's a question i can't really answer. maybe it did....or maybe thecomputer was just in a good mood that day.

but all that set aside, i should be able to get some good numbers with the renesis/fc project i'm doing. that one is my personal vehicle, so it'll bet played with daily until i get something noteworthy.

from what i've seen from other people, i'm hoping for maybe 210 whp conservatively, but hopefully a bit more. but only time and a lot of work will tell that whole story.

i should hopefully get the car running by the end of the year, so look for some results (positive, OR negative) sometime in january. i'm a relatively humble persn, and i'm not afraid to post up any mistakes i make just so the info is out there and other guys can learn from them and correct them. but hopefully we'll be able to get some true-to-life idea about what the engine itself is capable of, without the factory ecu limitations.

after all the ported n/a, ported turbo, then maybe a bridgeport in the not-too-distant future, i'm hoping to see something in the neighborhood of 230-240 n/a whp, with good street manners, and not too much noise. don't hold me to that, but that's the tentative goal, anyway. and i still want to go all out with a bone-stock engine too, just to see what the story is....exhaust port only, intake port only, etc etc.... if i had the time, money, and enough engines and donor vehicles to play with, i'd be more than happy to devote a substantial amount of time to all this.

and if all THAT works out, i'll be offering renesis swaps for fc's and fd's. i do have one potential fd/renesis pj in the works, but that'll probably not be until next summer, so i'll just post up when and if it comes to life.

so for now, let's just stick with what we got, and hope for some more impressive results in the future. my knowledge, not only on the renesis, but tuning and rotaries in general has grown by leaps and bounds since the beginning of this thread. i honestly expect some good, solid, REPEATABLE numbers in the future.

this is really exciting, being able to be a part of the "ground floor" of all this stuff.

btw, if anyone wants to do a ported renesis with an interceptor, i'm willing to do all the work involved for next to nothing as far as $$ is concerned--just to get more experience, and more information available to everyone.

patrick_andraste

Not too much noise?

all my vehicles set off car alarms. I just have to try harder with my -8

Noise is good.