Fuel524

i am new to the rotary sceene, but am a gear head. i jutst purchased the car 3 wks ago, new toyo proxes tires, filter, sprkplugs,and oil filter change(10w30mobilsnthetic), and amsoil tranny and rear diff syn. also have removed the ac hardware all of itinside and out, as well as a SHO taurus elec. fan with temp control relay. I am in the navy and have access to lift and hobby shop etc. so i emptied out my cats as the car has 119k on it. it back fires like a bad outa hell. pretty scary. i use 92 octane gas with valvoline 2stroke. would my gas type be causing it to backfire or is it something else?

BigJim

backfiring as in throwing flame outta the back>? cause if so any rotary engine without cats will do it. Dont be scared, just make a video and get a kick outta it. Rotary engines dont burn all of the fuel injected into the engine so its expelled through the exhaust and wihtout the cats it is able to ignite and blow out teh back

Stoops417

i still dont' understand why my car doesn't backfire... i don't have cats... perhaps becase my car doesn't run rich?

BigJim

yea, its when the car runs rich that it happens, i forgot to throw that in. When u are decellerating it usually happens, if it happens more often, change ur mixture would be my suggestion

Fuel524

maybe a lower octane fuel would decrease this backfiring for i live in a military community and i think it scares ppl and draws saome unnecessary attention. also i am planning on purchasing a RB full srteet port exhaust.

BigJim

ull still get the fireball with that exhaust. Theres an adjustment screw to thin your fuel mixture. Id lean it out a little and see if the car stlil runs right and stops fireballing

kel26

I'm a newbie here too and I've just gotten hold of a ITA first gen from a friend of mine. He has told me that (stock)rotaries do not like high test as a rule, and that it really doesn't help to run anything higher than about 89 octane . Anyone have any thoughts on this?

BigJim

ive read alot of threads and ive heard the same thing. Rotaries just cant burn enough gas so why waste your money on the higher octane when its just going to get wasted. Ive even heard about some guy that races these getting below regular octane fuel for racing. Not sure how true all that is, but its just what ive heard

JIMMY54

iTrader: (2)

Adjust the TPS and the backfires will stop.

I can turn my backfiring on and off. Too be honest after 3 years of LOUD *** backfiring you begin to miss it.

It's like a friend saying hello as you tach drops from 4,000 to 3,000.

Also in my experience, 94 octane makes my car run smoother. Octane boost makes it even better.

JIMMY54

iTrader: (2)

whoops I didn't realize you are running carb. I can't help with that....

However have fun with it.

I was inside of another car beside a backfliring rx7 and we thought that there was something wrong with our car, cause you can't tell were it came from. But afterwards i remembered my car and I figured it out. Most people have no idea what that sound is and would never guess its your car. so have fun

gummie

synthetic = bad!

85rotarypower

Its generally good to run the lowest octane fuel you can find. 87 is normally good. The race engines don't even run anything higher than 89 unless its turbo charged. Then you run the highest you can find.

Fuel524

thankks for the advice, this is my first time with this forum i think it is radical. how do i adjust my mixture(screw) where i have a haynes manual but i cant find it and i know where my idle adj. screw is. any halp on that. also i will have to wait on the lower octane gas for i just filled it up. also somehing to take into consideraion i have removed the belt for my air pump. also any detailed info on removal of air pump, but nots rats nest. thank you guys rock.

1stgen4life

iTrader: (1)

I was thinking the same thing, but he said something about valvoline 2 stroke, so I assumed that he was premixing. If you are not, then you should not be running synthetic oil. I'm not trying to start a flame war with synthetic users, but I have read that to be a bad thing.

Fuel524

i have only used syn. oil once and i just stareted using premix. so ill use regular oil from now on. also i have heard rotarys dont like to start when theyre cold. when they do how should it sound. like it does when theyre warm or kinda like a boing boing missing. then it goes away

MicahMan

i have a 83 gsl and the cat is hollowed out and i had a really bad backfire because i had a small leak in the exhaust and my carb needed to be rebuilt cause there was too many gas fumes in the exhaust. i get more response and less backfire with 87 octane gas. rotary cars dont like high octane unless you have performance upgrades.

Fuel524

cool, thanx for the help.

Northern 7

iTrader: (3)

Not flammin ya buddy but if you are going to tell someone not to use Synthetics, you should explain why. The fact that you read it somewhere is not good enough to justify as being "advice". BTW, I use synthetics and I read somewhere that they are a Good thing - I think it was Racing Beat

Back to topic - your car shouldn't back fire and there are a number of reasons why it might; including timing, vac leaks, exhaust leaks, poor ignition or carb issues.

Fuel524

northern7, to my knowledge i have no vac leaks, exhaust leaks. if you could help me with some indications of a bad carbura8er, or ignition, probs. it would be a great help.

83gslRX-7

dont worry bro my car backfires too. i love, what other car shoots flames when either shifting slow or downshifting.. nothing like beating the **** out of a civic then getting in front of them downshifting, an d.. BAM!!! flames all over them haha i love it!

Fuel524

can someone tell me where i can find out how to check for proper timing it seems to run fine but i want to be sure cuz the last owner new nothing about rotaries just did regular maintenance, so some help there would be nice as far as using synthetics i too have read tey r good mazdatrix uses redline in everything that needs lubricating. a lil help would be great