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NorthRyder
01-22-2004, 02:27 PM
What exactly makes the car backfire with a fireball out of the exhaust. I saw this 300z clip and it looked sick. Any tips on how to achive this?? thanks

mirek
01-22-2004, 07:20 PM
:rolleyes: :rolleyes: :confused:

Mikester
01-22-2004, 07:34 PM
make sure you dont fill up at esso at yonge/finch... i live and drive around there and dont want stuff hitting me from the explosion

NorthRyder
01-22-2004, 07:46 PM
hahahhahah no not like that.
This might sound rice but the Skyline in FAF2 had that. And i have seen race cars do it to. i heard this happens when u take away the CAT and make the exhaust a straight pipe. but i still dont know what causes it!!!

mirek
01-22-2004, 07:47 PM
a buildup of gases in the exhaust all being ignited at the same time

NorthRyder
01-22-2004, 07:49 PM
so how do i achiave this. and can i contol it somhow. so it doesnt shoot out infront of a cop!! thanks

blacknblue-e30
01-22-2004, 08:26 PM
thats tough, your best bet is probably just to duct tape a few sparklers on your car, then light them whenever you want.

hehe :)

mirek
01-22-2004, 08:36 PM
hehe, some roman candles in the back, and a spark switch hooked up to an igniter in your rear ;) *par-t* *uzi*

NorthRyder
01-22-2004, 08:51 PM
LOL

330DTM
01-22-2004, 09:14 PM
I can't give you a full detailed explaination, but fire usually comes out beacuse of unburnt fuel being ignited while up/down-shifting. This may require the removal of the catalyic convertor.
It's pretty cool when fire spits out, I've seen my buddies A4 doing it and it sounds like a Sonic Boom firecracker as the fire comes out from the exhaust. It's usually pretty easy to do it on turbo cars, but I've seen a friend's civic w/Teg type R engine conversion doing it before from an APEXI exhaust :D

Someone verify with me on the reason for fire coming out. I'm almost sure that that's a factor as to why it happens.

Justin e36
01-22-2004, 09:23 PM
Backfiring is when the fuel-air mix burns back towards the carburettor, resulting in flames/sparks out the top of the engine

Afterfiring is when the fuel-air mic continues to burn towards the exhaust manifold, resulting in flames/sparks out the exhaust

Afterfiring is commonly mistaken for backfire - and both are usually caused by sticky valves or build up of carbon etc in the head of the engine.

Older type cars, (without a fuel cut-off solenoid in the carby), can be prompted to backfire fairly easily. (older muscle cars). you can then turn the ignition off while coasting in gear, (using the momentum of the vehicle to 'suck' fuel and air in, and pump it straight out again without burning it), after this is built up --- turn the ignition back on again, thereby causing a flaming afterfire. Unfortunately, if you have a vehicle manufactured after about 1973, you will have to bypass the fuel-cut solenoid to achieve this.

On a newer car though... keeping it healthy and forcing it to afterfire is still unknown to me... I know certain cars are prone to this, such as Porche... also to backfiring within the engine, leading to engine damage.

325iSBimmer
01-25-2004, 06:27 PM
My blazer used to do that exact same thing....it was a carburated and one of the jets got cloged and there was way too much fuel going into the engine and If you just pined it form idle it would start afterfiring and it looked pretty cool coming out of the dual exhausts but that was short lived when it backfired and caught the insulation on the hood on fire. I you get a normal non-turbo charged or high compression engine to backfire/afterfire it probably will be running like shit...

Gamite
01-25-2004, 07:23 PM
Originally posted by 328DTM
I can't give you a full detailed explaination, but fire usually comes out beacuse of unburnt fuel being ignited while up/down-shifting. This may require the removal of the catalyic convertor.
It's pretty cool when fire spits out, I've seen my buddies A4 doing it and it sounds like a Sonic Boom firecracker as the fire comes out from the exhaust. It's usually pretty easy to do it on turbo cars, but I've seen a friend's civic w/Teg type R engine conversion doing it before from an APEXI exhaust :D

Someone verify with me on the reason for fire coming out. I'm almost sure that that's a factor as to why it happens.


*BANG*

Autotechnica
01-25-2004, 08:22 PM
It does look cool once in a while, but I would prefer not to have that *snap* *crackle* *pop* sound everytime I let off the throttle at higher RPM's.

Aside from the sound, racing wise people used this to boost up the RPM's when they lifted their foot off the throttle, it would keep the revs up and give them more power once they got back on the throttle. Very common in WRC cars.

Anyways, while your at it might as well add a "fake" blow off valve. ;)

Bry

Justin e36
01-25-2004, 10:58 PM
fake blow off valves?.. never even knew fake ones existed. rice as they may be.... they sound god damn intimidating.

BMW_7
01-26-2004, 12:07 AM
I think to do something like that you should have a small pipe that leads fuel to the exhaust tip, and have a spark plug in the exhaust tip.

So inside you can flip the switch on, and fuel gets sent up to the tip, and gets ignited by the spark plug. Would be a cool site when peeling out...

That is more like flames coming out of the exhaust constantly..


BTW this site is cool http://www.gotflames.net/

Justin e36
01-26-2004, 12:09 AM
yeah... not very healthy for your car though. Also not really a fan of igniting explosions and fires in non-controlled situations... but hey, that's just me. Anyone wants to try, be my guest. :D

BMW_7
01-26-2004, 12:27 AM
Justin, do you have these? http://www.procarparts.com/product/BMW-3SR-9298-DIRC-4DXX-TL2X.JPG

Autotechnica
01-26-2004, 12:39 AM
Originally posted by Justin e36
fake blow off valves?.. never even knew fake ones existed. rice as they may be.... they sound god damn intimidating.

Intimidating if he has a turbo. There are products which simulate the sound of a blow-off valve to make it sound like the car has a turbo installed. Pathedic, this is the true definition of rice.

Justin e36
01-26-2004, 01:01 AM
Originally posted by BMW_7
Justin, do you have these? http://www.procarparts.com/product/BMW-3SR-9298-DIRC-4DXX-TL2X.JPG

Yes I do.. had em since April or so. I just wrote something about them in the 1994 318is Exhaust thread over here (http://www.maxbimmer.com/forums/showthread.php?threadid=27536&highlight=crystal)

But I'll paste what I replied with. (was asked if I had any pics of them on my car.) *note: I changed some wording here... I wasn't really clear when I initally posted this. If you have any questions though, let me know.

Unfortunately I don't... all the pics of my ride (including the one in my sig) are old. I got the crystal tails recently... haven't seen another e36 on the road with em though. Could just be the area I'm living in though... but personally, I think they look better than the stock euro tails.

A word of warning... these tails are designed for the Euro cars, which have different wiring schematics to accomodate the rear fog light. (which is cool, so you can do a Euro Fog Tails mod) ...

However, when you install them initially you'll find your turn signal coming on instead of your break light on one side, and a reverse light on the other side. Your other reverse light, and your brake light will be on all the time (as running lights)... it's really messed up.

So you'll need rewire it... I've also had to tap my brake light on the left, and run a wire to the bulb on the right.

So if you're not comfortable doing this, I don't recommend it... it's not that difficult to do, if you have the mindset for it.

Also, the build-design is different from the stock tails, and the usual red/white tails... this one is all wires crisscrossing to each bulb (and much cheaper quality mind you... even though from the back you can't tell, as they seat perfectly.) Because of this design, you can't change the bulbs easily from the holes in your trunk. There will be times (90% of the time) when you'd be forced to unwire everything, remove the complete tail light, change the bulb, and wire it all back up / install it again. A real pain in the ass during winter months.

I'll see if I can get some recent pics for you though...

Justin e36
01-26-2004, 01:02 AM
Originally posted by Autotechnica
Intimidating if he has a turbo. There are products which simulate the sound of a blow-off valve to make it sound like the car has a turbo installed. Pathedic, this is the true definition of rice.

True... real turbo with a blow-off valve is :eek: though... had some dude in a Talon (stock turbo) revving beside me from a red light. I didn't even bother the attempt. Just kinda sunk into my seat and pretended to disappear. *shiner*

Jammasterj
01-27-2004, 07:03 AM
hahaha i smoked a talon off the line in my old MX-6
the guy rolled down his window and i had a blown exaust at the time so the mx-6 sounded all beefed up when really it just had a hole in the resinator...lol

so anyways this guy was with his girl and was all like lets go...
so i agreed and he turned to me and said hey, no matter what happends in the end. i still have the girl...
i turned to him and said, ill be looking at her in my rear view....

to make a long story short. i SMOKED him! he couldn't drive...*wiggle*