Big Bang Firing Order
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Teching In
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Big Bang Firing Order I've been reading a little bit lately about the "Big Bang" firing order that has been used by motogp racers.
http://en.wikipedia.org/wiki/Big-bang_firing_order
In short the theory is that by firing 2 cylinders at the same time you end up with a power stroke every 360 degrees instead of every 180 on their four cylinders. In motogp this was used to allow the tire more time to recover from wheelspin and gave higher corner exit speeds as a result.
I've been looking around a little bit and can't seem to find any application of this being used in cars. I'd be interested to know if anyone has any knowledge on the matter. It seems like there could be some small benefit to small tire cars if the motor could handle the increased imbalance?
As a side note, I would love to hear a v8 in this setup, i'm sure it would sound bad ***.
http://en.wikipedia.org/wiki/Big-bang_firing_order
In short the theory is that by firing 2 cylinders at the same time you end up with a power stroke every 360 degrees instead of every 180 on their four cylinders. In motogp this was used to allow the tire more time to recover from wheelspin and gave higher corner exit speeds as a result.
I've been looking around a little bit and can't seem to find any application of this being used in cars. I'd be interested to know if anyone has any knowledge on the matter. It seems like there could be some small benefit to small tire cars if the motor could handle the increased imbalance?
As a side note, I would love to hear a v8 in this setup, i'm sure it would sound bad ***.
Teching In
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On a V-8 considering conventional intake and exhaust, I think this would be a hindrance due to overwhelming exhaust flow in single bursts and basically the same for vacuum pulling from the intake as there would be no time for the air charge to equalize. These are just ideas that came to mind, but I think it would be kind of a neat concept and sound if you made a big V-8 fire 2 cylinders at a time without tearing itself apart.
I also don't think it would be too hard to do, most likely just a camshaft and some tune tweaking. I was thinking of building a Frankenstein golf cart like I saw recently with a V-8, may just have to find a 4.8 and see if I can have somebody grind a camshaft to test your theory.
Edit: After some brainstorming, my thoughts about intake and exhaust may not be as much of a hindrance as first expected, considering the two cylinders would be on opposite sides of the block, but firing and fuel rations would have to be dead even or you would loose power due to one cylinder doing more work while the other is trying to catch up vs each cylinder being on its own power plane or stroke as were accustomed to.
I also don't think it would be too hard to do, most likely just a camshaft and some tune tweaking. I was thinking of building a Frankenstein golf cart like I saw recently with a V-8, may just have to find a 4.8 and see if I can have somebody grind a camshaft to test your theory.
Edit: After some brainstorming, my thoughts about intake and exhaust may not be as much of a hindrance as first expected, considering the two cylinders would be on opposite sides of the block, but firing and fuel rations would have to be dead even or you would loose power due to one cylinder doing more work while the other is trying to catch up vs each cylinder being on its own power plane or stroke as were accustomed to.
Last edited by K1SSRSS; May 30, 2014 at 04:59 PM.
Thread Starter
Teching In
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Yea, I definitely don't think it would be very hard to do. Getting a custom cam speced for it would be relatively easy. I haven't used my copy of HP Tuners in a while but I don't believe its possible to change anything with firing order in the stock ECU's, would have to splice some ignition/injector wires but I don't see why that couldn't work.
I wish I had the money/time to test this, but it is definitely all theoretical right now for me. If anyone has anymore input/experience on the subject I'd love to hear it.
I wish I had the money/time to test this, but it is definitely all theoretical right now for me. If anyone has anymore input/experience on the subject I'd love to hear it.
TECH Apprentice
Joined: Feb 2014
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From: Baton Rouge La
I cut a 6 cyclinder cam in half welded it back together. The customer had this great idea to fire two cyclinder at once. So we made the cam for him. He was a dirt track racer. First problem he had was firing both cyclinders at once. After he got it to fire at the same time it shook itself to death. It did really run that we'll of course it was my fault
I told him not to do it. Don't try to out trick yourself.
I told him not to do it. Don't try to out trick yourself. 
