Well since i made my first prototype steel header that made 7 hp more on my RotoTest comparing to stock log type manifold i had some problems contacting my Tig guru and header maker. He will not answering the phone, so i have decided to contact another company that shall build and weld my Renesis header. The plan is to launch the header to public in June if no more mishappens takes place! I will post data on my webpage that shall be up in a few weeks.

/Lasse

Great job! What other modifications accompanied the 7 HP increase? Cat elimination, ECU tuning? Thanks for your time and contributions!

Laters!
Edgardo

:ylsuper:

Great work! I look forward to the product. Any pictures?

he's got a muffler that will give you 10 hp too ...

Any updates on this project or your porting project?

Finally i have been talking to my "header maker"! He's back in business and shall begin constructing a small 5 series of 3 pipe stainless Renesis headers for me. When these headers is finished i don't know yet, but i keep you informed!

/Lasse

good news---keep us udated
od

Post some pics if you can.

Looking forward to seeing your header!

coolio!!

Sorry for this, i will post on Friday (i'm just screw things up today!)

/Lasse

yeah, i'd like to see some pics. regardless, i'd like to say good job on getting that far despite whatever people may about it.

Is there any difference in sound?

Ok! I know it,s already Saturday and no pic yet...but as soon as my friend is home to me with his camera he can upload it for me.

Yes there is a little deeper throatier tone not much but it's there!
I think when i measure the sound with a db meter 20 inch 45degree backwards the exhaust it was like 82-83dbA. That was with only the complete exhaustsystem (no header)

/Lasse

Great job! What other modifications accompanied the 7 HP increase? Cat elimination, ECU tuning? Thanks for your time and contributions!

Laters!
Edgardo

+1
and great job! cant wait till the pics get posted!!!

update?

I would like to see some pics

If you actually made 7 hp i would not post any pictures until you have a patent for it.Most headers now only get from 3 to 4 hp ,you never know who might be looking here and steal your design.

Pics or it didnt happen...

i want to see some proof!! i neeeeed power!!! Muahhahah

Pics or it didnt happen...

+1

If you actually made 7 hp i would not post any pictures until you have a patent for it.Most headers now only get from 3 to 4 hp ,you never know who might be looking here and steal your design.


those 3-4 hp ones claimed 10 - 15, get a clue ...

First i actully made on my Rototest 10-12 hp more with "my" Ferrita complete exhaust system minus header. The car went from high 6s 0-60 mph to 6.23s with exhaust system and Shell V-power 99 octane fuel and Motul oils. Then i dynoed with my steel header on same RotoTest hub unit and made +7 hp at 8000+ rpm. 0-60 mph went down to 5.86s. Of course i know this is not proof enough but when Peter G finally makes the first stainless header(hopefully in July) i will have proof with dyno curves and some photos. I have not driven the car since 7 weeks though i had a gearbox failure but next week i will also add an Interceptor X.

/Lasse
www.wankelracing.se

Can you really drop the 0-60 time by almost half a second by gaining 7hp at 8000+ rpm?:spank:

No not really but everytime i "race" i improve on starting and shifting of course. Today i have mount the ACT flywheel and stock clutch, so now i'm only waiting for Wednesday next week to pick up my 8"

/Lasse

any more info on your header ?

pics we need pics .................

wow, this is taking a bit too long... :(

suckers are always willing to bite ...

suckers are always willing to bite ...

wait wait wait....

suckers are always willing to suck...

cant bite due to lack of teeth...

stop spreading lies...

heh...

Thing is, i will wait for 1st week in August to have Peter G begin with my stainless Renesis header. I know i'm very lazy about posting pictures, but i have lot of work to do in my rotary business so sometimes a simple thing as posting a picture takes long time for me but i will do my very best.

/Lasse

Zzzzzzzzzzzzzzzzzzzzzzzzz

wait wait wait....

suckers are always willing to suck...

cant bite due to lack of teeth...

stop spreading lies...

heh...

valid point - your contributions are most informative :rolleyes:

Now i'm heading to www.ferrita.se to pick up my first 5, 2.5" stainless steel sport exhaustsystem. They come with a 100 cells racecat and front 2.5" full flow silencer. Rear is a 2.5" pipe with a full flow rear single silencer not baffled as stock but same size as stock,along with double 3.5" chrome tips. This complete system picked up +10 hp on my RotoTest. I will have my new webmaster to take some pictures of the system and have it on display next week on my website www.wankelracing.se

/Lasse

3 months and still not 1 picture? Come on Lasse, you need to show us something........anything?

www.wankelracing.se

/Lasse

If only I could read that...:banghead:

If only I could read that...:banghead:What, you don't know Swedish? :uhh: :)

I lost most of it when I learned Russian

If only I could read that...:banghead:

I know i must translate to English! But question is when?... Next week!

/Lasse

I lost most of it when I learned Russian

My pig latin is still ubparsay.

To all you disbeleivers, here finally it is! ML wankeltrim prototype header.

http://www.molnsatra.se/bil/header.jpeg

/Lasse

alrite, we got a pic!

so a 7hp inrease, eh? sounds pretty good. or did i just read 10?

The increase + 7 hp was after i added my Ferrita 2.5"sport complete exhaust system.

/Lasse

wait. what is the ferrita 2.5 exhaust system? so are you saying you got 7hp with the header, and the exhaust together?

wait. what is the ferrita 2.5 exhaust system? so are you saying you got 7hp with the header, and the exhaust together?

I would think then that the header adds the standard 3hp. It looks really cool though.

wait. what is the ferrita 2.5 exhaust system? so are you saying you got 7hp with the header, and the exhaust together?

The Ferrita complete exhaust system is 2.5" with a front race cat and a little round full flow silencer + a rear tube connecting to a dimensionally RX-8 stock rear muffler but with fullflow type,y tubing in muffler exiting to 2 rear 3.5" chrome tips. This system alone gave 10-12 flywheel hp more on my RotoTest. Then i added my prototype header and that added + 7 hp at flywheel. I will try to translate my homepage to English and ad some pictures of the exhaust system the coming week.

/Lasse

So, with the header and the exhaust system and highflow cat, we can expect 17 to 19 hp increase?

2.5 inch pipe is not unexpected. Most seem to think that they need 3 inch tubing. 2.5 inch should flatten out the powerband a bit. This is more in line with the figures that rotarygod comes up with. (Yes RG, some of us pay attention)

17 hp from exhaust system? But that is with a race/high flow cat --right? Plausible!
Curious with what you have done with the center port--can you give us another picture showing the header ports? if not then I understand--have to guard development secrets.
Important step toward that hp goal of yours and i am following closely. If that goal is obtained (and I am optimistically cautious:)) then i will not need to go FI.
header looks good for prototype. Are there air holes for the air pump present?
olddragger

oooooooo okay:). sounds good man. as long as it really works. im first in line!!!

17 hp from exhaust system? But that is with a race/high flow cat --right? Plausible!
Curious with what you have done with the center port--can you give us another picture showing the header ports? if not then I understand--have to guard development secrets.
Important step toward that hp goal of yours and i am following closely. If that goal is obtained (and I am optimistically cautious:)) then i will not need to go FI.
header looks good for prototype. Are there air holes for the air pump present?
olddragger

Yes it's a Ferrita made short race cat. The center ports of the header is more like stock, but with little modification. If i remember right the biggest length difference is 4" of the rear and middle tube but only 1" of the front and rear tubes. No there are no holes in header for air pump, but will be with final product. If now only PeterG could inhibate his vacation "lol".

/Lasse

oooooooo okay:). sounds good man. as long as it really works. im first in line!!!

I will have to wait until late August to dyno test the "new header, though PeterG is beginning to do a jig and meticously build first stainless prototype with what i hope all primaries within 1/2" length difference.

/Lasse

looking good man--looking good.
olddragger

(Yes RG, some of us pay attention)
LOL!!!

The exhaust ports themselves are much smaller in area than the exhaust runners are which is why I think 2.5" is fine if done properly. If you go purely off of runner area, a 3" is about right. Unfortunately Mazda can't seem to get port area and runner area matched up very well. Even if a 2.5" makes slightly less top end power, I'll bet it makes more average power everywhere else. Someone go test that statement and report back.

hey lasse, i'll be your guinea pig with the header:) hAHAHA

LOL!!!

The exhaust ports themselves are much smaller in area than the exhaust runners are which is why I think 2.5" is fine if done properly. If you go purely off of runner area, a 3" is about right. Unfortunately Mazda can't seem to get port area and runner area matched up very well. Even if a 2.5" makes slightly less top end power, I'll bet it makes more average power everywhere else. Someone go test that statement and report back.



Lets ask Lasse since he seems to have all the needed equiptment?

Have you tested out a 3" exhaust as well as the 2.5" that you are currently using? What about a 2.75"?

I can say that i have not tested any 2.75" or 3" on my N/A RX-8. But it can be easily done i just have to ask Ferrita and they will make a bigger bore exhaust. Maybe i'm gonna test the 2.5" and a 3" prototype on Lennarts RX-8 race car on my RotoTest dyno? Lennarts RX-8 has a Procharger kit from DNA on his stock block Renesis engine that is pumping out 326 hp at rear wheels on a DynoDynamics hub dyno. Should be interesting to see the results!

/Lasse

Is this being sold as a full exhaust system? Price estimate yet?

After 1.5 months any updates Lasse?

Cheers

jird20

This looks promising for all us normally aspirated guys. Is that a big dent I see in the front runner? :rolleyes: I'm more curious about dropping weight. Any target weight reduction numbers verses stock weight?

http://www.molnsatra.se/bil/header.jpeg

Well one thing i can say for sure is that i am still waiting for Peter G to get his hands dirty on manufacturing the headers! I talk to him last Monday and then he said he should "only" do some Ford Cosworth turbo headers. This means that hopefully he can start with my headers late next week. I am not gonna comment or write anything more about the header before he makes the first one!Then i will post some pictures. About the weight i think it will be around 2 lbs lighter than stock.

/Lasse

Oh, this sort of header thing could be beneficial to Remote turbo setups like mine :)

:rolleyes:

Headers may not be of any benefit to N/A apps but definitely to F/I or nitrous apps. I already have a p.m. out to Lasse about a 3"-collector version.

A small weight reduction fro me until RP gets his thingamabob completed for my conversion from N/A to F/I.

:D:

I wonder what this type of header does for the exhaust note? I really do not want a raspy sound. I want a deeper sound.

^ Yes I know, but that post confused me because it says (no header) when he did the dba test. ??

Yes there is a little deeper throatier tone not much but it's there! I think when i measure the sound with a db meter 20 inch 45degree backwards the exhaust it was like 82-83dbA. That was with only the complete exhaustsystem (no header)

I'm the only one interested it seems, so send me one for Christmas please :)

Any problems with tuning?

dyno late august????

for the 1 billionth time, a multi-tube header is worthless on a zero-overlap timing Renesis

english please

I'm more interested in weight savings and sound changes

update?

LOL!!!

The exhaust ports themselves are much smaller in area than the exhaust runners are which is why I think 2.5" is fine if done properly. If you go purely off of runner area, a 3" is about right. Unfortunately Mazda can't seem to get port area and runner area matched up very well. Even if a 2.5" makes slightly less top end power, I'll bet it makes more average power everywhere else. Someone go test that statement and report back.

Newbie here, hi all.

Slight thread hijack here but hey!
Just flicking through the exhaust threads for some tips on making up our exhaust system to mate to our own headers, and picked up on this, nice to see someone confirmed my calculations, I was getting a bit worried I'd gone too small seeing all the big bore systems on here! :)

is this header still in the works

for the 1 billionth time, a multi-tube header is worthless on a zero-overlap timing Renesis

You can help pull the exhaust gases out but that's about all, saying that though, those exhaust ports need all the help they can get!

You can help pull the exhaust gases out but that's about all, saying that though, those exhaust ports need all the help they can get!

ummm...ok...

with overlap...the in hole is open when the out hole is open...
zero overlap...the in hole is open when the out hole is closed...

suck on a closed hole all you want...

savvy?

Your sucking the exhaust gases out, it's called scavenging, normally with overlap you get more effect because you can also help pull in some inlet mixture, you can't do this on the renesis but you can still help with the exhaust gas scavenging, savvy?

Your sucking the exhaust gases out, it's called scavenging, normally with overlap you get more effect because you can also help pull in some inlet mixture, you can't do this on the renesis but you can still help with the exhaust gas scavenging, savvy?

right but there exists a maximum theoretical gain to doing this on this type of engine...and in this case due to the design of the engine itself, the amount of possible gain is further reduced.

not saying do not do this...but setting a realistic expectation that this modification is not the same as in a piston engine where the gain is significant.

I agree, but there is some gain to be had, removing more combustion gases will also help draw in more intake charge when the chamber gets around to the intake port.

Slight gains, but gains all the same.

I agree, but there is some gain to be had, removing more combustion gases will also help draw in more intake charge when the chamber gets around to the intake port.

Slight gains, but gains all the same.

Well see thats just it...it fails my "efficiency" test...the costs for gain...bang for buck...

If your into racing...and I'm talking about hardcore racing...your probably going to be fabing your own header anyway...

This type of product in the other markets is aimed as a low cost easy NA mod with "butt-dyno" gains...

As much as I love aftermarket support for our cars, this is one market which has a very hard sell in the one argument that matters most...bang vs. buck...

Cost us £40 to make ours ;)

Cost us £40 to make ours ;)

Heh...when you make your own sure anything is cheaper...but thats when it starts becoming addictive...

Too addictive, got have this car done in a month and we're too busy tinkering! :lol:

for the 1 billionth time, a multi-tube header is worthless on a zero-overlap timing Renesis

I believe you cause I know you're not dumb, but then why did RE Amemiya build one of these headers? Are they tuning their Renesis with overlap (that even possible?) or is it just bling factor and weight-loss?

Also, if you're bored Team explain in more detail why multi-tube is worthless.

-Fil

ummm...ok...

with overlap...the in hole is open when the out hole is open...
zero overlap...the in hole is open when the out hole is closed...

suck on a closed hole all you want...

savvy?

right but there exists a maximum theoretical gain to doing this on this type of engine...and in this case due to the design of the engine itself, the amount of possible gain is further reduced.

not saying do not do this...but setting a realistic expectation that this modification is not the same as in a piston engine where the gain is significant.

Guess that answers my question...haha

Too addictive, got have this car done in a month and we're too busy tinkering! :lol:



nice...

There is most certainly a benefit to "scavenging" with a zero overlap engine! I know it's been stated many times that you can't get scavenging without overlap. You definitely can't get scavenging without collecting exhaust pipes such as true duals on a 13B but scavenging you can get with no overlap.

But how? When we think of scavenging, we think of the exhaust velocity pulling on the intake during overlap through the benefit of the low pressure wave behind it. Obviously we can't utilize this low pressure wave if there is no overlap. Or can we?

This low pressure wave, at vertain points in the rpm range depending on tuning, can in fact leave the chamber below ambient outside pressure. This means that when the intake ports open, there is a greater pressure differential than normal and the air in the port gets "moving" at a faster rate. Higher intake velocity helps cram more air into the engine. Keep this trend going and it will also help as the port closes. It will raise the average air speed velocity through the port which increases efficiency. Yes it can be done!

The downside to trying to do this is the evil siamesed center exhaust port. It completely messes up tuning in this manner. No matter how long your equal length header tubes are, there will always be an interference wave where the center ports come together which will off set what we are trying to accomplish with header length. There may be a way to "trick" this interference wave into becoming a positive effect wave however and you can't do it with 3 equal length pipes and only 1 collector.

On some old 4 cylinder engines, the original Mini Cooper comes to mind, there were only 3 exhaust ports. These engines had the 2 middle valves dump into a siamesed runner in a similar fashion to the Renesis center ports. I know someone is going to complain that the firing order of a 4 cylinder through these 2 ports isn't even and this is true but all we care about is acoustic resonance of the system and not so much how often pulses run through. The reality is that an even stream of pulses such as with the Renesis actually works more in our favor.

These older engines and cars did get raced. Keep in mind the Mini wasn't the only engine with a siamesed center section. It's just the only one I can think of right now. The race cars had some very creative exhaust designs to deal with the siamesed center ports. The most successful setups ever used on these engines utilized unequal length runners and dual collectors. The 2 outside exhaust runners were equal length as each other and collected with each other only. The center port was deal with in one of two way. One of them just being an addition to the other. The first way was to make this pipe anywhere from 30%-50% longer than the outer pipes and collect them downstream of the first collector at a second one. The length of this center pipe being the critical item to tune. You first figure out what the optimum header pipe length is and then base the outer pipes around this length. The center pipe length was then tuned. It MUST be collected farther downstream though as lengthening it and collecting it at the same point does NOTHING! RB tried this.

The other setup which was a variation of the above added a "dead leg" pipe to the center immediately after the port left the head of the engine. It gets tee'd off right at the entrance to the center runner. This pipe was the exact same length as the outer pipes but plugged off at the end.

Each of these setups tried to take advantage of acoustic resonance to help with a scavenging effect. Since sound waves are also energy, it was the hope that these acoustic waves, which are known to tune very well, would offest the negative waves that cancelled out the fact that the center ports were siamesed. Hymee proved in a dyno a few years ago that the center port has much more energy in it as it was the first to glow brightly in a dyno session. This is proof enough that the center needs to be treated differently.

However, NO ONE had addressed the center port in a different way. Until someone does, none of them will have any more spectacular results than any other setup. I don't care if it's cheap ebay crap or has RE-Amemiya stamped on it. None of them will give more than 4-5 additional hp. I don't care what they claim. The reason they gain anything at all is through additional flow. It has nothing to do with tuning. I know team has claimed that his works best but he won't say how it is designed. Until then I'm raising the bs flag. I'll keep it up after I see it if the center port isn't addressed uniquely from the rest too. He also says mine won't work. Maybe it won't. I don't know yet. I do know that I am the only one to address the center ports being siamesed and that gives it the greatest probability of success. That doesn't mean it will work any better though. One thing is for sure that a downside to my design is the space required to do it.

The reson I feel this has the most validity is that it isn't a new problem and that it has been solved in the past. That's a good place to start with a design for this engine. Only when someone tries it and proves that it doesn't work will I agree that NO header design out there will do anything other than any other. Up to this point, they don't. There are only a few more designs to eliminate. Mine included. It might not work. We'll find out someday I guess.

That's what I was trying to put across but nowhere near as eloquently.

I'd quite like your opinion on ours in regard to that though, as you can see the two outer ports run a far different exhaust length than the centre port and the centre port joins 2 inches further down the collector than the outer ports.

I'd love to weld the centre ports up and run a pair of small peripherals in their place, along with the outer side ports, but can't justify the cost at the moment.

That's what I was trying to put across but nowhere near as eloquently.

I'd quite like your opinion on ours in regard to that though, as you can see the two outer ports run a far different exhaust length than the centre port and the centre port joins 2 inches further down the collector than the outer ports.

I'd love to weld the centre ports up and run a pair of small peripherals in their place, along with the outer side ports, but can't justify the cost at the moment.

Haa...eloquently or as grossly detailed as only Fred can...

Tell me RG, do you buy keyboards in bulk to account for wear and tear? ;)

Hey, RG. Is it possible to create a center pipe with a divider that is extended to match the center port divider. In essense creating four ports with four pipes. The center two just happen to be siamessed.

Not really work?

Too hard to mass produce?

Be easier to have a bolt on CNC milled piece that fitted in and split out into two seperate pipes to use with a bespoke 4-2-1?

Be easier to have a bolt on CNC milled piece that fitted in and split out into two seperate pipes to use with a bespoke 4-2-1?

Unfortunately CNC machines are still expensive...but oh man...all the naughty things I would do to with that poor machine...

But having things CNC milled is fairly cheap if you do the CAD program yourself, I've had exhaust manifold plates milled before for less than 10 per unit, fortunately I have both a program and a CNC mill these days.....

RB tried a center divider and made a 4-1 header. I posted pictures of it a couple of years ago. The conventional 3 pipe header made about 4 hp and the 4-1 made about 5 hp. Little difference. I would like to see this tried but instead collecting it into 2 separate pipes. 1 for each rotor. Then adjusting it's total length. I don't like the idea of 1 collector. Even trying 2 separate pipes all the way out would be an option. The 13B guys call this a true dual system and it works better on engines with less overlap than more. It would be interesting to see how it works with no overlap.

Phillip I think your header looks great. Very nice work. I don't think the short collector distance difference that you have is going to do anything though. You do have some good distance to play around with though so you could actually try many different things and learn what works best. I can't wait to see your project when it's done.

Aye, if there's one thing we have it's room!

Hopefully the shorter pipe length will make the difference if I've done the maths right - it's actually joining 10" before the outer pipes, even though it doesn't look it, if not I'll try the centre section and dual pipes you've suggested.

And if that doesn't work the housing is going on the milling machine.

kinda reminds one in theory of the expansion chambers that 2 cycle bikes have used?
Understand the benefit on the na engine---if you throw a supercharger on the engine(not turbo) would not the benefits be greater?
oldscdragger

The problem with 2 stroke theory as applied to a rotary is that 2 stroke tuning not only helps pull gasses out of the chamber but also push some back in near the end of the cycle. We don't want that.

I dont know what in the hell i am talking about:)
oscd

I think the best thing I can do here to help out is to dyno the car with a standard manfold on if I can get hold of one and it'll fit, then put ours on, then try it with the centre pipe taken around the back of the engine as a completely seperate pipe with it's own silencer.

That should help with an idea of where to head with the systems

I think the best thing I can do here to help out is to dyno the car with a standard manfold on if I can get hold of one and it'll fit, then put ours on, then try it with the centre pipe taken around the back of the engine as a completely seperate pipe with it's own silencer.

That should help with an idea of where to head with the systems

That's always the best way. You never know, you may discover that really long pipe work good on the Renesis which is why we've never seen anything do much.

We seem to have hijacked Lasse's thread a bit. Does everyone remember Hymee's pics?

http://www.rx8club.com/attachment.php?attachmentid=61089&stc=1

We seem to have hijacked Lasse's thread a bit. Does everyone remember Hymee's pics?

http://www.hymee.com/rx8/images/dscn7061.jpg

http://www.hymee.com/rx8/images/dscn7063.jpg
http://www.rx8club.com/attachment.php?attachmentid=61080&stc=1

http://www.rx8club.com/attachment.php?attachmentid=61081&stc=1

http://www.rx8club.com/attachment.php?attachmentid=61082&stc=1

http://www.rx8club.com/attachment.php?attachmentid=61089&stc=1

http://www.rx8club.com/attachment.php?attachmentid=61090&stc=1



kev,

nice to see you around.. king of the quote pic posts..

that is a damn sexy cat and resonator..


beers :beer:

The power gain he reported with that header wasn't spectacular but also included removing the cat which alone adds about 7 hp or so. I think he made somewhere around 12-13 hp with that exhaust which adds proof that headers can only give around 5 or so more peak.

A video he posted of that engine on the dyno also clearly showed the difference in energy in the center port vs the outers. The center pipe glowed MUCH faster than the outers did. This is proof that it needs to be treated differently.

Rotarygod, the only header I've seen that used the 4 pipe design was Knight sports's header.

http://www.knightsports.co.jp/blog/imgs/SE3P_EXMANIFOLD2.JPG

http://www.knightsports.co.jp/blog/RX-8-SEP3P/post_se3p_independent.html

What do you think of that header in comparison to the others?

all are absolutely pointless ....

all are absolutely pointless ....

Which begs the question why hasn't anyone else designed a "log" type of header similar to yours? It seems to be the simplest design and since there is no overlap complicated tube style headers may be convoluted and unnecessary.

Because tubular manifolds can still provide a benefit to an engine with no overlap....

you can build a better manifold than the OE design, but a tubular design only complicates the fabrication and cost without any payoff over a log manifold

you can build a better manifold than the OE design, but a tubular design only complicates the fabrication and cost without any payoff over a log manifold

but they look so pretty. :wiggle:

as long as you don't mind a heavy car and a light wallet :p:

you can build a better manifold than the OE design, but a tubular design only complicates the fabrication and cost without any payoff over a log manifold

You can't provide the correct harmonic pressure pulses with a log manifold, which still help, even with no overlap.

You can't provide the correct harmonic pressure pulses with a log manifold, which still help, even with no overlap.

I appreciate your design and the theory that Rotarygod has presented as viable. I just think you will have a hell of a time putting that manifold you have created - or similar variant - into an RX8 chassis. It doesn't have nearly the room to work with that you do. It could probably be done but you will also probably be fabricating a complete exhaust system at that point, too. Thats not going to be cheap for your average joe that doesn't have access to a lift and welding equipment/skills. I think all that is being said by Team is that for the effort and money required to make the project work in a stock RX8 chassis you might as well go with a lightweight OE-like design and call it a day as only modest HP gains will come from an all out N/A setup anyway.

It would be a lot of time and money I agree.
But then so is any modification compared t just buying a faster car, so....

$5,000 USD into a, well designed F/I setup can make you faster than $5000 towards a faster factory car, IMO.

And there are not many other cars in the price range of the RX that have as well an engineered chassis, suspension or brakes to begin with so you will stop and turn faster as well. but now i'm just playing the fan boy roll.

Keep in mind that my header design is not proven. No one has built one. I truly can't say it does work. It is just my approach to dealing with the setup we have. The lack of overlap does pose a problem. For all I know my design is viable. However is it viable on an engine with no port overlap. That design is nothing more than a hypothesis I have based on what I know. I do admit that it will be very hard to fit it in an RX-8. I am going to install a Renesis in an old RX-7 so I have plenty of room. I just have no idea when I'm going to get around to this though as I have a wedding and a new house to worry about first.

Team is a smart guy. The exhaust issue is the one thing that we have disagreed about. Not because I don't think his design is bad but because he blatantly feels my design which he also hasn't tried won't work. I prefer to keep an open mind but do admit that it might not work as I hope it will. The only way to find out is to build one and that's not something that get's priority from me. If I actually owned an RX-8 you can be rest assured that I'd have tried it by now.

I do think Team is correct based on what we know to this point that there isn't necessarily any point in building a full tubular header. I know for a fact that Racing Beat has tried very many different combinations and lengths and has never really shown an advantage of one over the other. It doesn't matter if it's been long or short. They all give 4-5 more horsepower over the stock log style manifold. This seems to suggest that the only thing that matters is flow and once you hit what you need there is no more to be had. Up to this point tuning hasn't been beneficial to the Renesis. Flow has. Team has come up with a simple design that gives the gains of any other header system out there and for simplicity sake it's hard to justify doing it any other way.

I actually have 4 different designs that I still want to see tried. Keep in mind NONE of them would be emissions legal. I have no way of knowing up front whether any of them will work better than anything else that has been done. From the sheer number of designs that have been tried so far it would seem the odds are against me. That's OK though. This only means they haven't been proven not to work. My optimism for these designs comes from the fact that although many different setups have been tried, they have all fundamentally been just 2 separate designs. They have been log and equal length header. The other couple of designs I have contemplated are not either of these. Since none of these have been proven not to work, I have to hold out some optimism that there's a chance that they will. These other designs are the only things that take into account the crazy center port characteristics.

I do know that a true 4 runner header has been made and it too showed no significant gains over the 3 runner which would suggest that this isn't an issue. However I feel that the design that was tried was a bit too short and not quite what I want to try.

Here are a couple of simple things I want to try. The first is to build a true 4 tube header but then collect the rear rotor and front rotor pipes so that now we have 2 pipes. The front rotor and the rear rotor. Now we try a couple of things. The first is to have 2 totally independent pipes going all the way out through 2 mufflers. True dual exhaust. This works fantastic on stock port 13B's but it's effectiveness actually falls off as port overlap increases. That's an interesting trait. Does this mean that it would be beneficial with no overlap?

The other thing to try is to collect these 2 pipes at the back of the car right before the muffler to have what the RX-7 world refers to as a "long primary". This is my personal favorite setup on a 13B but then again that's not a side exhaust port engine. I've talked about the other setups before.

I'm not saying any of them would work any better. They are different though and no one has tried them. Until someone proves them not to work, I have to believe that they might. If someone does try this and shows no significant gains, go ahead and just build tubular manifolds all day. When it's all said and done, after everything has been tried, the best product will be the one that is the simplest that still does what it's supposed to. From what we have seen so far, Team just might have this part figured out.

Keep.....(Unproven design based on a theory...however lack of time and resources to pursue).....first.

Team.....(Team's solution is elegant and exists...it isn't the only answer however, simply the only proven one...if I could I would have tried it, cuz I likes to tinker).....now.

I do.....(Suspect that full tubular headers may not be the way to go, based on the results of tests done by Racing Beat which did not produce significant gains over the log style manifold. Log style is an elegant solution.).....other way.

I actually.....(I would like to test some designs strictly for educational purposes.).....port characteristics.

I do.....(The 4 runner header tried was a bit too short, but that horse has been beat.).....to try.

Here are.....(We should test a true 4 tube header and collect them so each rotor has its own independent poopie chute to the planet...since it has interesting characteristics in a no overlap situation.).....overlap?

The other.....(In the next test, create a "long primary" by collecting them at the rear of the car.).....before.

I'm not.....(It will possibly all be filled with complete FAIL...but it would be fun to experiment...at the end of the day, the one which works as advertised wins...and its hard to beat the existing solution which is elegant.).....figured out.

So after reading all that...how much do you need for material costs and when would you like my time/car to mess around with this stuff?

I'm going to be moving to FI soon...but due to technical difficulties not for a while...so in the interim I don't mind messing with it in N/A trim...and I'll have it probably ripped apart with extra parts and stuff...

I mean...if your just wanting to mess around with it...

I'm willing to bet it took you longer to write all of that than it did just to read and comprehend it!

I'm willing to bet it took you longer to write all of that than it did just to read and comprehend it!

Heh...yeah...however it does indicate that I at least DID read it...

You might be seriously long winded...but its always good stuff...ramble on...ramble on...

zero overlap = closed chamber

closed chamber = no flow momentum potential past evacuation

I wish anyone the best to try and pulse additional flow out of a closed chamber.

zero overlap = closed chamber

closed chamber = no flow momentum

I wish anyone the best to try and pulse flow out of a closed chamber.

The good ol...suck on the end of a sealed straw argument...

Heh...I think everyone agrees...but its all in the name of "screwin around"...

The real question is what is the pressure inside the closed chamber? If it isn't at absolute vacuum (and it isn't) then there's still some potential left. Extracting it is an entirely different thing though.

zero overlap = closed chamber

closed chamber = no flow momentum potential past evacuation

I wish anyone the best to try and pulse additional flow out of a closed chamber.

The trick is the evacute the exhaust side of the chamber more effiecently, as the chamber does not empty completely - more vacuum = more inlet charge when the inlet port opens.

=You can suck on a closed straw.

Even without overlap there could be a benefit from scavaging, a vaccum created before the port opens may help(but by how much?)

Not a huge amount, but we'll found out when ours goes on the dyno this month.

The trick is the evacute the exhaust side of the chamber more effiecently, as the chamber does not empty completely - more vacuum = more inlet charge when the inlet port opens.

=You can suck on a closed straw.

Right...I was just pointing out that the "suck on teh zero overlap" is the "suck on a closed straw argument"...

When the straw opens up...the negative pressure is going to suck whatever is on the other side...

Which was the conclusion of the "closed straw argument"...

Happy Birthday Lasse! (I'm still older than you though :) )

Thank you! But i don't feel that kind of old when playing with my rotors... I have decide not to write anything about my header project thread that i started, but all i can say i have not given it up!

/Lasse

wow, just read all this and i just thought of something that no one has said yet, ohhh im so tempted to pm rg