The RX-7 was able to spit flames because of the overlap in the intake and exhaust ports. The old 13b was also bridge ported for more horsepower by many racers and this made the flames even more visible.

The Renesis Engine does not have this overlapping problem, so I would not expect to see any natural flames.

 

What I have observed with the Borla exhaust is that you do get flames if the car has been driven hard and has had enough time to get the exhaust very hot.

You can get a burst of flames, along with a pop or two, by quickly lifting off of the throttle after it has been wide open (pig rich).

If the exhaust is hot enough, you will end up with continuous flames out of the tips (predominately the left tip) by just running under full throttle.

I'll see if I can capture it on video this weekend.

 

before i had traded in the FD i had a full exhaust setup with no cat and shot flames all the time. this occured usually when i got backfire because of the low amount of pressure build up. it makes a popping sound as speed racer stated and will just shoot flames everytime it popped. i haven't knoticed any popping at all in the stock exhaust setup on the rx8.

Dan

 

this is precisely it. you can shoot flames in ANY car you want, not just a rotary... but yeah, they happen to be much better at it

this is because of the inherently less efficient combustion chamber shape of the wankel engine, and also why they get low fuel economy (no, this has little to do with consumption problems of the RX-8, i'm simply saying you'd never see a wankel in an economy car application).

the overlap between the intake and exhaust of the heavily ported semi-perhipheral 13B's creates tons of breathing at high rpm (seeing how porting will evolve with six side ports on this engine will be terribly interesting), and what really brings the flames is the earlier opening exhaust port, sans catalyst.

simply because the RX-8 doesnt' have any overlap doesn't mean it can't shoot flames like crazy, as speedracer attests to (even with cats). the rich mixture of the intake charge is what's leaving the soot on your tail pipes, so ignite that, and you've got your flames.

 

hmm.....im really tempted to go catless. however, i live in california so theres probably little chance of that going over too well.

 

sure the fire shooting out of exhaust is cool... but the consequences for getting caught with that is freakin HORRIBLE. you can ahve your car confiscated in CALIFORNIA and crushed... you could catch someone on fire - like we have ENOUGH DAMN FIRES HERE ALREADY! (ash is raining here). and you can seriously hurt someone by shooting flames at objects... I would only do this on a track car or PURELY show car you do not drive all the time. Think before you do something stupid, please!

 

um, are you kidding?? i've never seen any car (less those which have fuel feeds and igniters right at the exhaust) that actually projects a meaningful amount of flame out the exhaust: when a car "shoots" flames, it's a pop of uncombusted gasoline going up (in a rather unclean fashion) once it hits the oxygen rich atmosphere combined with the heat of the exhaust itself, but this isn't a flame thrower, it can be as much as setting a marshmallow on fire for a few seconds (not a fire that's actually gonna burn anything). maybe soot-up the paint around the exhaust tip something nasty, but that's it.

 

I actually got a few pops out of the stock exhaust when I first got the car. It only happened when I held the throttle full for a second and then let off quickly. I haven't really noticed it since the car has been broken in.

 

that's precisely it: the stock muffler and cat keep the car fairly tame, but open it up a little more, and those'll be big back-firing plumes.

 

Thanks wakeech! You took the words right out of my mouth.

The photo that I posted makes the car look like it's a flame thrower but if they had watched my video they would have seen that the bursts of flame last about a second at most. IMHO it is hard to catch something on fire when it is exposed to heat that briefly.

 

*Puts Nomex suit on*
I like neon undercarrigage lights too. IMO, the Rx-8 could not be accused of being "rice" if neons were fitted because it has power to go with it. Rice=All show, no go.
Oh yeah, you do get tacky crap for cars I agree with that being rice.
Sorry for going of topic here.

 

OK I have personalyl seen several cars launch flames because they are running a highly aggressively tuned fuel mixture. I have seen skylines, silvias, rx-7s, and truenos do this on the track also. rally cars also. in japan they have flame launching contests that extend up to 6-15 feet beyond the vehicle...

here is a pic of a VW Gold GTi tuned by Dahlback Racing... it seems to be SHOOTING FLAMES!

 

now that is sweet
great pic

 

My race shops FD with full dp and exh sure belches out some good flames when we are @ the track. I tried to get pics but couldnt catch any. I knew people who would purposely throw HUGE fireballs from rotaries but they were carbed so I dont think EFI will let you do it the same.

bring car to speed, 3rd or 4th gear throttle to floor, kill ignition while throttle still on the floor, wait 5-10 seconds and return key to on position as if you were bump starting it. and BOOOOM a huge fireball will erupt out the back.

 

Actually, Efini 8 has a point even if it is lost in his hyperbole. Even a hot muffler has the potential to start a nasty fire in dry enough conditions. A good number of wildfires in the last few years have been traced back to 2 or 3 matches or a stray cigarette butt, which would seem almost as innocuous as a flaming marshmallow.

 

My owner's manual for the SA states that I shouldn't park on a grassy area after a long drive, because my exhaust could start a fire. That's before I deleted the thermal reactor and heat exhanger! I would imagine my RB header/presilencer gets even hotter.

As far as flames go, my car used to spit flames with the stock exhaust, but now that I've deleted my air pump and installed the header system, it doesn't shoot flames, afterburn or make any untoward noises. Kinda boring really. My stock system was good for a backfire that sounded like a rifle shot if I went from WOT to instant decel, like preparing for a turn in autoX.

 

I need someone tell mi whats heel is this for?
Somebady nouse it?

 

Good question, I've wondered that too. Looks like an exhaust cut-out of some sort, but if that were the case, I would expect there to be a flange to cap it off for the street, or possible some sort of a bypass valve.

Anyone?

 

I dont know what that is but i think putting a switch to open it and byspass the mufflers might give you good power on a drag race although loud as hell

 

If that were a picture of a system for a 2 stroke, say a new Yamaha snowmobile, it likely would be a Resonance Chamber used to cancel a particular frequency.

 

Now there's a thought!

 

is that the stock exhaust? or aftermarket? if so what kind?

 

Aftermarket, and I'm pretty sure that exhaust came from Knight Sports. Check out http://www.knightsports.co.jp/whatsnew-index.html

 

Everyone is talking about the different cat-backs on the market and how much power they will make. Now, I am pretty familiar with the rotory engine, however, after the exhaust is released from the exhaust port, it must go into some type of manifold before the first catalytic converter. Everyone is concerned with how much power each cat back is going to make. What i want to know is who has the ***** to fabricate a race exhaust to eliminate all the cats and have it be stright piping (Or a "high-flow cat") from the motor onward, in order to make the MAXIMUM amount of power.

BTW: I know I am totally ignoring warranties in this thread, but i don't really care. I's prefer if anyone is going to cry about warranties, just dont post in this thread at all.

 

YES!! I want a full exhaust too! :D

Racing ceramic coated header, ultra high flow, high temp, high performance cat (or no cat) and complete cat back!!