A/F ratio for flames? Also, for driving under vacuum.
08-17-06, 06:09 PM
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A/F ratio for flames? Also, for driving under vacuum.
I know alot of people look down on people who want to shoot flames. But it's something unique to our engines (I think) in doing it without add on spark plugs. And I seen some built up V-8's at a car show with spark plugs in the tailpipes and their flames were quite pathetic in comparison to what I've seen rotaries do, I thought they'd be bigger, brighter, and longer lasting but the cars I saw doing it were not. I would not add spark plugs but wouldn't mind tuning the car to do it on it's own sometimes.
Anyway, I'm running a Microtech with a large streetport, RB full exhaust, and Jacobs Rotary Pro pack. What A/F ratio is good for making flames? Like 11:1 or lower? My wideband only reads to 10:1 and my first attempt at tuning the highest idle vacuum fuel setting pegged the gauge. Also do you need to do anything with the timing? I do have that shock absorber on the throttle cable removed but can't remember what it's called. Will the ignition box make it hard for the car to flame? I can bypass it easily (just switch connectors) but it's not really worth it.
And for the more important question, a mechanic that tuned my car before said you wanted close to 14:1 AFR for acceleration under vacuum, not just cruising, is this true? I know that is good for cruising and 11:1 is good for boost. He also left the timing settings alone saying there was some internal map that it was basing off of since it just adds some as boost gets higher, is that correct or will it harm the engine. Not really worried about extracting maximum horsepower as it would probably only get 10hp or so more I think, just want the timing set reliablly for the engine, kinda like a factory tune would be.
Anyway, I'm running a Microtech with a large streetport, RB full exhaust, and Jacobs Rotary Pro pack. What A/F ratio is good for making flames? Like 11:1 or lower? My wideband only reads to 10:1 and my first attempt at tuning the highest idle vacuum fuel setting pegged the gauge. Also do you need to do anything with the timing? I do have that shock absorber on the throttle cable removed but can't remember what it's called. Will the ignition box make it hard for the car to flame? I can bypass it easily (just switch connectors) but it's not really worth it.
And for the more important question, a mechanic that tuned my car before said you wanted close to 14:1 AFR for acceleration under vacuum, not just cruising, is this true? I know that is good for cruising and 11:1 is good for boost. He also left the timing settings alone saying there was some internal map that it was basing off of since it just adds some as boost gets higher, is that correct or will it harm the engine. Not really worried about extracting maximum horsepower as it would probably only get 10hp or so more I think, just want the timing set reliablly for the engine, kinda like a factory tune would be.
08-27-06, 01:23 AM
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Yeah, it runs at 180 in the cooling system and I've got it tuned to about 14:1 while cruising and 11:1 under boost, just don't know what number to shoot for at high vacuum. I don't have room for an EGT gauge either, I like the factory clock/warning lights.
08-27-06, 01:49 AM
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the easiest way is to ground out the ignition so it wont send a spark to the plugs. The way I do it is a 2step rev-limiter that cuts ignition at whatever I set it at.
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10-27-06, 08:51 AM
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i thought flames were due to fuel burning up in the exhaust system. so basically do some sort of ignition cut while the exhaust is really hot(after hard accel) and bingo....flames.
10-28-06, 12:11 PM
#12
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I've noticed that if you tune rich under decel, then you get a lazy big *** flame.
If you tune LEAN, you get lots of staccato POPS out the exhaust with really short flames but they are really LOUD.
Turn off your DECEL CUT - I dunno what MT calls it...
-Ted
If you tune LEAN, you get lots of staccato POPS out the exhaust with really short flames but they are really LOUD.
Turn off your DECEL CUT - I dunno what MT calls it...
-Ted
11-12-06, 03:57 PM
#13
Cutting the ignition then turning it back on will do it.
My brothers Datsun 260z had a mechanical fuel pump so you could leave it in gear, turn off the key, and let it pump gas into the cylinders. Then push in the clutch and turn the key on. Then BOOM burn baby burn!
My brothers Datsun 260z had a mechanical fuel pump so you could leave it in gear, turn off the key, and let it pump gas into the cylinders. Then push in the clutch and turn the key on. Then BOOM burn baby burn!
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