We started using the LS firing order in several different engines and have had mixed results.All positive but not the same gains in every engine.
Some BBC stuff we do showed very positive gains over the std. firing order versus the 4-7 swap but compared to the LS order it was night and day. Both power and torque showed impressive gains compared to std firing order with the same cam profile and no other changes were made to cam timing ignition carb etc.
I am currently testing SB blk and BB mopar to find out how they respond to the firing order differences. Since the 4-7 swap is commonly available for these engines the logic is since they benefit form a 4-7 swap they should really like the LS order better.
ProPower engines wrote: ↑Wed Feb 07, 2018 2:04 pm
We started using the LS firing order in several different engines and have had mixed results.All positive but not the same gains in every engine.
Some BBC stuff we do showed very positive gains over the std. firing order versus the 4-7 swap but compared to the LS order it was night and day. Both power and torque showed impressive gains compared to std firing order with the same cam profile and no other changes were made to cam timing ignition carb etc.
I am currently testing SB blk and BB mopar to find out how they respond to the firing order differences. Since the 4-7 swap is commonly available for these engines the logic is since they benefit form a 4-7 swap they should really like the LS order better.
Post your results please. I never found a LS FO core for any mopar. Unless I bought an UGL core. If you can find a core with the LS FO (or Cadillac as I call it) it certainly won't hurt anything.
Well if you have this data why don't you share it to end the debate. Otherwise you too only share an opinion......
How was Ford so much more advanced than everybody else for decades?
If the guy who runs the dyno at Hendricks says it works, it probably does.
What’s completely fascinating about firing order is how it effects camshaft velocity variation. Talking to Billy Godbold, a V8 can use a more aggressive lobe than a I6 which can use a more aggressive lobe than a I4. A single cylinder has to be really smooth. An even fire V6 can run a more aggressive profile than an odd fire V6.
...Something to chew on.
I listened to the Billy Godbold interview and it was great. But there were also people who tested V6 engine packages using the odd and even fire combinations and found no real advantage either way. Why? Also how would moving the firing order around in the engine change the pulses felt in the valvetrain? You still have four pulses per rotation in a V8 what's causing the difference? Is it a difference in the way the crankshaft behaves as RPM changes? Is it strictly in the valvetrain? Is it in the induction? Is it in the exhaust?
I've heard all kinds of different ideas about why different firing orders were tried but none seem very solid except for the one I heard long ago about a NASCAR team. The idea was simple: put the two adjacent cylinders that fire 90 degrees apart that are in the rear of a Chevy in the front to even out the temperature in the engine so that they could run more tape on the radiator and go faster at places like Daytona. That seems most probable.
If the guy who runs the dyno at Hendricks says it works, it probably does.
What’s completely fascinating about firing order is how it effects camshaft velocity variation. Talking to Billy Godbold, a V8 can use a more aggressive lobe than a I6 which can use a more aggressive lobe than a I4. A single cylinder has to be really smooth. An even fire V6 can run a more aggressive profile than an odd fire V6.
...Something to chew on.
I listened to the Billy Godbold interview and it was great. But there were also people who tested V6 engine packages using the odd and even fire combinations and found no real advantage either way. Why? Also how would moving the firing order around in the engine change the pulses felt in the valvetrain? You still have four pulses per rotation in a V8 what's causing the difference? Is it a difference in the way the crankshaft behaves as RPM changes? Is it strictly in the valvetrain? Is it in the induction? Is it in the exhaust?
I've heard all kinds of different ideas about why different firing orders were tried but none seem very solid except for the one I heard long ago about a NASCAR team. The idea was simple: put the two adjacent cylinders that fire 90 degrees apart that are in the rear of a Chevy in the front to even out the temperature in the engine so that they could run more tape on the radiator and go faster at places like Daytona. That seems most probable.
Really it's all the above, just in varying degrees. (No pun intended! Lol)
Your most probable understanding, the evening of temperatures, by far has the least impact!
I can't get into it too much, but Bob has posted info and links in this thread (Google has Nothing on that guy! Lol) that covers most all of it in one way or another.
ProPower engines wrote: ↑Wed Feb 07, 2018 2:04 pm
We started using the LS firing order in several different engines and have had mixed results.All positive but not the same gains in every engine.
Some BBC stuff we do showed very positive gains over the std. firing order versus the 4-7 swap but compared to the LS order it was night and day. Both power and torque showed impressive gains compared to std firing order with the same cam profile and no other changes were made to cam timing ignition carb etc.
I am currently testing SB blk and BB mopar to find out how they respond to the firing order differences. Since the 4-7 swap is commonly available for these engines the logic is since they benefit form a 4-7 swap they should really like the LS order better.
Post your results please. I never found a LS FO core for any mopar. Unless I bought an UGL core. If you can find a core with the LS FO (or Cadillac as I call it) it certainly won't hurt anything.
Testing 1st with the 4-7 swap cams in both FT and roller using a 408 and 440 mules. The LS cams have to be special ordered but they can be had. the starting point will be FT because of costs to do rollers.
I want to play with the FT stuff 1st as it is the easiest to make cam changes and see results but I also have several intakes that want testing as well.
It will be coming up after I get the testing done to move onto the LS cams to get made but we have a local cam guy we work with and getting changes done is not a long time waiting just need a few cores to start with.
But when I get to the roller stuff yall will be the 1st to here about it
statsystems wrote: ↑Wed Feb 07, 2018 2:39 pm
Post your results please. I never found a LS FO core for any mopar. Unless I bought an UGL core. If you can find a core with the LS FO (or Cadillac as I call it) it certainly won't hurt anything.
I believe LSM has that core. And has had it for quite a while.
statsystems wrote: ↑Wed Feb 07, 2018 2:39 pm
Post your results please. I never found a LS FO core for any mopar. Unless I bought an UGL core. If you can find a core with the LS FO (or Cadillac as I call it) it certainly won't hurt anything.
I believe LSM has that core. And has had it for quite a while.
Yes they do make them.
That is who they will be ordered from when I get there
I listened to the Billy Godbold interview and it was great. But there were also people who tested V6 engine packages using the odd and even fire combinations and found no real advantage either way. Why? Also how would moving the firing order around in the engine change the pulses felt in the valvetrain? You still have four pulses per rotation in a V8 what's causing the difference? Is it a difference in the way the crankshaft behaves as RPM changes? Is it strictly in the valvetrain? Is it in the induction? Is it in the exhaust?
I've heard all kinds of different ideas about why different firing orders were tried but none seem very solid except for the one I heard long ago about a NASCAR team. The idea was simple: put the two adjacent cylinders that fire 90 degrees apart that are in the rear of a Chevy in the front to even out the temperature in the engine so that they could run more tape on the radiator and go faster at places like Daytona. That seems most probable.
Really it's all the above, just in varying degrees. (No pun intended! Lol)
Your most probable understanding, the evening of temperatures, by far has the least impact!
I can't get into it too much, but Bob has posted info and links in this thread (Google has Nothing on that guy! Lol) that covers most all of it in one way or another.
Google is my friend! I'm a scientist by training - half the battle is just finding good data and learning how to optimize searches. I usually have a target person (Harold, Mike, Billy, etc.) and then put some 'trigger' words after their name. You never know what'll pop up! Harold left a lot of great stuff scattered across a couple sites.
Google is my friend! I'm a scientist by training - half the battle is just finding good data and learning how to optimize searches. I usually have a target person (Harold, Mike, Billy, etc.) and then put some 'trigger' words after their name. You never know what'll pop up! Harold left a lot of great stuff scattered across a couple sites.