I apologize for asking this question....
4 cycle engine and number of cylinders
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A single plane V8 has 1.5 times the vibration as a four cylinder of half the displacement. If you take two inline 4 bangers and make a V8 out of them, you wind up with 1.5 times total vibration, and not twice as much total vibration.
Going into the "wayback machine" to 1988, you first started to see flatplane cranks in NHRA prostock engines. This fad lasted 2-3 years and then it was decided it just wasn't worth it, as gains in exhaust efficiency just didn't compensate for intake distribution problems, and the really horrific vibration.
At the same time there were some really "out there" big bang setups. There was a 2X4 with two pistons firing simultaneously. Then there were even odder firing arrangements. 90-180-90-90-180-90 or some such arrangement.
The 180 degree cranks were easy to tell by sound. The "big bang" stuff always sounded like a sick engine.
Eventually this stuff fell by the wayside as better valve spring material/manufacture, and better transmissions/more gears became the norm, and engines were safely revved higher.
There are some neat one off parts sitting around in a few shops out there.
Going into the "wayback machine" to 1988, you first started to see flatplane cranks in NHRA prostock engines. This fad lasted 2-3 years and then it was decided it just wasn't worth it, as gains in exhaust efficiency just didn't compensate for intake distribution problems, and the really horrific vibration.
At the same time there were some really "out there" big bang setups. There was a 2X4 with two pistons firing simultaneously. Then there were even odder firing arrangements. 90-180-90-90-180-90 or some such arrangement.
The 180 degree cranks were easy to tell by sound. The "big bang" stuff always sounded like a sick engine.
Eventually this stuff fell by the wayside as better valve spring material/manufacture, and better transmissions/more gears became the norm, and engines were safely revved higher.
There are some neat one off parts sitting around in a few shops out there.
Originally Posted By: A_Harman
Originally Posted By: ZeeOSix
No ... each 4-stroke "cycle" comprises 720 degrees of crank rotation (ie, 2 crank revolutions). If people don't use the correct terminology all thoughts are jumbled.
There are never two pistons in the same part of the 4-stroke cycle on a typical, common V8 engine.
You're the one with terminology trouble.
A "cycle" is 720 degrees of crankshaft rotation.
A "stroke" is 180 degrees of crankshaft rotation.
Hence the term "4-stroke cycle".
Again, people are not reading very well. I said above in the quote that "each 4-stroke cycle comprises 720 degrees of crank rotation."
So how is that different than saying "A cycle is 720 degrees of crankshaft rotation"? Really, sounds pretty much the same to me.
So however people want to say it, the bottom line is that a 4-stroke engine's crankshaft MUST rotate 720 degrees (2 crank revs) in order for a piston to go through a complete cycle of the 4-stroke process. That was the message I was trying to convey.
Interesting discussion, as can be seen there are many, many engine designs out there, which makes it hard for everyone to stay on the same page.
Originally Posted By: ZeeOSix
No ... each 4-stroke "cycle" comprises 720 degrees of crank rotation (ie, 2 crank revolutions). If people don't use the correct terminology all thoughts are jumbled.
There are never two pistons in the same part of the 4-stroke cycle on a typical, common V8 engine.
You're the one with terminology trouble.
A "cycle" is 720 degrees of crankshaft rotation.
A "stroke" is 180 degrees of crankshaft rotation.
Hence the term "4-stroke cycle".
Again, people are not reading very well. I said above in the quote that "each 4-stroke cycle comprises 720 degrees of crank rotation."
So how is that different than saying "A cycle is 720 degrees of crankshaft rotation"? Really, sounds pretty much the same to me.
So however people want to say it, the bottom line is that a 4-stroke engine's crankshaft MUST rotate 720 degrees (2 crank revs) in order for a piston to go through a complete cycle of the 4-stroke process. That was the message I was trying to convey.
Interesting discussion, as can be seen there are many, many engine designs out there, which makes it hard for everyone to stay on the same page.
Here's some cool info on cross plane and flat plane crankshafts.
Link: Crankshafts
Link: Crankshafts
Here's a link for details of many different multi-cylinder engine designs. As can be seen, there are many ways to design a multi-cylinder engine.
Link: Multi-Cylinder Engines
Link: Multi-Cylinder Engines
How do you make an LS sound like a 4 cylinder?
Convert it to flat plane. This engine kind of sounds like a Honda in this video. A 5.9L boosted Honda
Funny how it's a completely different engine, but could produce a similar sound signature. It's all about the length and volume of the pipes and the shape and volume of the ports, and the timing, spacing and distribution of cylinder events. With this OHV flat plane LS, the timing gives it the basis to mimick a multivalve 4 cylinder engine. Lingenfelter's super high redline just compliments that effect
Convert it to flat plane. This engine kind of sounds like a Honda in this video. A 5.9L boosted Honda
Could someone please describe the firing order of this engine: (shown in animation)
https://www.youtube.com/watch?v=wBTF5Ps4Scs
https://www.youtube.com/watch?v=wBTF5Ps4Scs
Originally Posted By: KevGuy
I apologize for asking this question....
No No , don't do that, we love this stuff. No one is throwing rocks and this is good discussion ! At least I've enjoyed it !
I apologize for asking this question....
No No , don't do that, we love this stuff. No one is throwing rocks and this is good discussion ! At least I've enjoyed it !
can i shift a little. my dad ask this Q. chevys, chrysler V8s have the number 1 cyl on the cyl that the con rod is the most forward. but ford has the cyl number 1 on the con rod that is the second one back from the front?
Morris,
Australia had it's own home grown V-8 small block,and they staggered the block to the reverse of the American way of doing things.
The forward most cylinder (number 1) is on the RHS of the engine (from the driver's position) rather than the LHS for the American Iron.
Reason being that with RHD, the RH forward arrangement gave more room for steering/clutch/brakes.
Australia had it's own home grown V-8 small block,and they staggered the block to the reverse of the American way of doing things.
The forward most cylinder (number 1) is on the RHS of the engine (from the driver's position) rather than the LHS for the American Iron.
Reason being that with RHD, the RH forward arrangement gave more room for steering/clutch/brakes.
Here is an interesting design. It's a 120 degree V6. It has 3 crank throws, which results in a very robust crankshaft. The exhaust exits upward, placing the turbocharger above the V. It is the proper and natural configuration for a V6 engine. It also results in a low center of gravity.
Originally Posted By: KevGuy
I apologize for asking this question....
I'm assuming that your question is basically asking about engine balance and smoothness. Here's a good article to read:
http://www.caranddriver.com/features/the-physics-of-engine-cylinder-bank-angles-feature
Any engine configuration can be balanced by counterweights and bank angle to make them run smoother. However, there are some engine configurations that do not need counterweights. These are boxer engines, straight-six, VR6, and I believe a V-12 and W-12.
I apologize for asking this question....
I'm assuming that your question is basically asking about engine balance and smoothness. Here's a good article to read:
http://www.caranddriver.com/features/the-physics-of-engine-cylinder-bank-angles-feature
Any engine configuration can be balanced by counterweights and bank angle to make them run smoother. However, there are some engine configurations that do not need counterweights. These are boxer engines, straight-six, VR6, and I believe a V-12 and W-12.
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Cujet, that mill is suhh-wheeet Is that an airplane engine? All this stuff about V8 and V2 engines is purely entertainment for me. In line sixes have 3 pistons opposed perfectly by a mate, creating a balanced state and the least vibration. V 12s are even better but beyond my resources. I'm bad with the terms, but I do know that in line sixes are the smoother and longer lived of the designs.
Originally Posted By: jrustles
How do you make an LS sound like a 4 cylinder?
Convert it to flat plane. This engine kind of sounds like a Honda in this video. A 5.9L boosted Honda
Funny how it's a completely different engine, but could produce a similar sound signature. It's all about the length and volume of the pipes and the shape and volume of the ports, and the timing, spacing and distribution of cylinder events. With this OHV flat plane LS, the timing gives it the basis to mimick a multivalve 4 cylinder engine. Lingenfelter's super high redline just compliments that effect
I met john L once. Truly my most respected engine builder, and a true camshaft guru.
Anyone remember him showing up at Car and Driver's top speed shootout many years ago in a stock bodied Camaro that went over 200 mph?
I love his naturally aspirated preferences, though. He does wonderful things with engines and puts the power where it really works...
How do you make an LS sound like a 4 cylinder?
Convert it to flat plane. This engine kind of sounds like a Honda in this video. A 5.9L boosted Honda
I met john L once. Truly my most respected engine builder, and a true camshaft guru.
Anyone remember him showing up at Car and Driver's top speed shootout many years ago in a stock bodied Camaro that went over 200 mph?
I love his naturally aspirated preferences, though. He does wonderful things with engines and puts the power where it really works...
Originally Posted By: Cujet
Here is an interesting design. It's a 120 degree V6. It has 3 crank throws, which results in a very robust crankshaft. The exhaust exits upward, placing the turbocharger above the V. It is the proper and natural configuration for a V6 engine. It also results in a low center of gravity.
Yep, 120 degree bank angle is THE perfect bank angle for a V6, just like 90 degrees is perfect for a V8. What engine is that BTW?
Originally Posted By: SteveSRT8
I met john L once. Truly my most respected engine builder, and a true camshaft guru.
Anyone remember him showing up at Car and Driver's top speed shootout many years ago in a stock bodied Camaro that went over 200 mph?
I love his naturally aspirated preferences, though. He does wonderful things with engines and puts the power where it really works...
Heck yeah! I'd love to have a beer and a chat with him. Never met him though
Here is an interesting design. It's a 120 degree V6. It has 3 crank throws, which results in a very robust crankshaft. The exhaust exits upward, placing the turbocharger above the V. It is the proper and natural configuration for a V6 engine. It also results in a low center of gravity.
Yep, 120 degree bank angle is THE perfect bank angle for a V6, just like 90 degrees is perfect for a V8. What engine is that BTW?
Originally Posted By: SteveSRT8
I met john L once. Truly my most respected engine builder, and a true camshaft guru.
Anyone remember him showing up at Car and Driver's top speed shootout many years ago in a stock bodied Camaro that went over 200 mph?
I love his naturally aspirated preferences, though. He does wonderful things with engines and puts the power where it really works...
Heck yeah! I'd love to have a beer and a chat with him. Never met him though
Last edited:
Originally Posted By: andyd
Cujet, that mill is suhh-wheeet Is that an airplane engine? All this stuff about V8 and V2 engines is purely entertainment for me. In line sixes have 3 pistons opposed perfectly by a mate, creating a balanced state and the least vibration. V 12s are even better but beyond my resources. I'm bad with the terms, but I do know that in line sixes are the smoother and longer lived of the designs.
Is that why you have the 528 in your sig? My dad has a 123 body 280TE Benz and that engine was sweet. Too bad it wasn't taken cared off well. Inline sixes are my favorite engine designs also. But, it also depends on what car it's in. BMW and the old Jaguar XJS made nice ones.
Cujet, that mill is suhh-wheeet Is that an airplane engine? All this stuff about V8 and V2 engines is purely entertainment for me. In line sixes have 3 pistons opposed perfectly by a mate, creating a balanced state and the least vibration. V 12s are even better but beyond my resources. I'm bad with the terms, but I do know that in line sixes are the smoother and longer lived of the designs.
Is that why you have the 528 in your sig? My dad has a 123 body 280TE Benz and that engine was sweet. Too bad it wasn't taken cared off well. Inline sixes are my favorite engine designs also. But, it also depends on what car it's in. BMW and the old Jaguar XJS made nice ones.
That 120 degree V6 is an Audi diesel race car engine.
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