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-   -   lots of fire (https://www.rx7club.com/1st-generation-specific-1979-1985-18/lots-fire-680166/)

rotaxrave 08-15-07 08:20 PM

lots of fire
 
Well simply my car shoots fire when i let the engine wind down from above around 4000 rpm with it in gear and my foot off the throttle. My rear bumper is melting. The car still has the "thermal reactor" and ive tuned it to what i think is almost perfection. It doesnt miss or run ric or lean as far as i can tell throughout the entire rpm range. I know its normal for rotaries to backfire and shoot some fire. But 4 foot flames that are constant for more than ten seconds is dagerous. If i always put it in neutral and just use the brake there is never fire., or under acceleration or constant speeds.

83rx7boy92 08-15-07 08:30 PM

reinforce your bumper and enjoy the flame throwing lol

sly-sa22c 08-15-07 08:43 PM

wish my car would do that.

take chernobyl off and retune.

what exhaust are you running and does it backfire between gears?

Kentetsu 08-15-07 09:00 PM

Check your timing, and look for any exhaust leaks in the system. Air entering the exhaust system will result in backfire.

Bptznumba1playa06@sbcglobal.ne 08-15-07 09:48 PM

wish mine did that more often hehe cool shit brap brap boom!!!!!! always fun to see the look on other peoples faces when it happens.

rotaxrave 08-15-07 10:08 PM

well is it dangerous? You would think thought that if you are going 40 mph plus and the fire is shooting back away from you it would be really heading away from your car enough to not catch it on fire.

But its sweet cause if you race someone and when you reach the top of 3rd going like 80 then shift to 4th and let the engine wind down and they see blue flames swirling in your muffler then erupting into a flame the look on their faces is priceless. The car is not terrilby fast but the flames make it look really cool and high performance :)

Its got straight pipe and a magnaflow muffler which has withstood 4 months of this fire quite well.

maybe ill take some vid at night to show what it does. Its more ectreme than anyhting ive seen on youtube.

steve84GS TII 08-15-07 10:13 PM

You have a 79-80 thats doing the flame throwing?
Sig shows an SE,but you mention a thermal reactor, which is 79-80 specific.

If it is an older car with the reactor,and your not concerned with smog,you could try switching the trailing ignition to full time operation like the cat equipped 81-85 cars.The 79-80 cars would cut their trailing spark so there would be enough raw fuel entering the reactor to keep things reacting.They also ran richer carbs and the 79 had unreliable timing since it used points in the distributor.

Definately check the timing.If the car is all stock,it shouldnt blow flame.If its modified,then your mods arent compatible with the thermal reactor type smog control gear and thats likely the cause of the afterburning,assuming its all tuned right.

Echoing the others........yea,I wish my car did that.
With as much power as I make,and since stock rotaries can do it,I wish I could coax a flame or two from my engine!

Bptznumba1playa06@sbcglobal.ne 08-15-07 10:13 PM

cool post the url here id watch that video

rotaxrave 08-15-07 10:33 PM

no its an 84 se. I meant its a manifold, not a thermal reactor. I was just looking at the vacuum diagrams in the haynes manual and it confused me. When its dark ill try to get a pic. People used to follow me and tell me to shoot flames for me but after i raced my friend he pulled up to me cause i won and he just said. "Ithought your car caught on fire. Huge flame!" When i race a civic or prelude, they back off when i shift from 2nd to 3rd or let it wind down after im letting them catch up.

1badFB 08-15-07 10:38 PM

TPS ???

Shouldnt the -SE cut fuel on decel?

rotaxrave 08-16-07 03:56 PM

it doesnt cut the fuel if the throttle postion sensor is turned 25 turns in the wrong direction, so when the throttles are closed, it still is giving as much fuel as if they were open much more.

XLR8 08-16-07 05:07 PM

It's all in the muffler dude. If you don't want flames then put something on there that will choke it down.

You could be running on the rich side. Bad gas mileage? Drivability good?

rotaxrave 08-16-07 05:20 PM

used to suck. Now its like 16 city and lke 26 highway

drivability is great, it starts perfect, idles perfect, doesnt miss. I have a magnaflow muffler which suprising has held up quite well. It has withstood 3 months of backfires and fire and hasnt burned out or got any louder. Everyone says magnaflow shouldnt be used on rotaries but so far magnaflow is awesome. Really brappy sound, quite, low pitch idle, and at really high rpms it sounds kick ass. I like magnaflow

steve84GS TII 08-16-07 10:52 PM

Typically,yea the EFI engines should cut fuel on decel,but anything is possible if something is outta whack with them. And without a real diagnostics system,its tough to anylize the SE fuel system.

Is the AFM tilted or rotated at all from stock?
You have the stock injectors?The SE has the large,680cc primary only injectors,so I imagine they are a little rich at idle/off-idle pulsewidths.....rotary EFI is rich to begin with from the factory anyways,and they waste fuel out the exhaust by design.With no cats to munch it up,flames can be substantial and unavoidable.I have a Bonez main cat,no pre-cat, and Ive never seen a single flame from my S5 EFI.
Could be a rich adjustment on the variable injector resistor.

If it were me,and I didnt have to worry about smog......Id just weld on a turndown tailpipe like the Aussie's do and let the flames do their thing.All the more fun, and youll only scorch the pavement, instead of the bumper.


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