Where does the engine smoothness come from?

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squaredeal91

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I know I am late to the party but there is a lot of talk on various forums that swapping cams to the LS firing order makes SBC run smoother, reduce load to increase longevity, better mpg, and run cooler so you can put more timing in it and increase power and mpg.
I didn't know the LS is a different firing order than small and big blocks. But it's really interesting to me because comp makes a cam that swaps firing order on #4&7 I put one in my 454 a few years back. My firing order is now 18736542. It was said to help Smooth the engine.
 

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I didn't know the LS is a different firing order than small and big blocks. But it's really interesting to me because comp makes a cam that swaps firing order on #4&7 I put one in my 454 a few years back. My firing order is now 18736542. It was said to help Smooth the engine.
Curious as to whether you could feel a difference or run cooler?
 

squaredeal91

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Curious as to whether you could feel a difference or run cooler?
I wish I can tell you i can tell a difference
but I bought the engine as a core and I rebuilt it. I'd say it runs a little cooler than previous small block and I'm using same Radiator.
 

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It's fuel delivery, too.

Fuel injection (especially computer controlled fuel injection) allows you to tailor the air/fuel ratio across the entire map of engine RPM and load. Precise fuel delivery helps smooth the idle as well.

Carburetors are crude, crude devices, and are really just one step short of you riding around on top of the engine and dribbling fuel into the engine upon occasion.

K
Not if you know what your doin... proper jets for motor size correct float adj and choke settings and idle adj and correct mixture screw adjustments...
 

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Want your engine smoother than already designed? Take your engine to the machine shop and have it balanced. It's usually done with a rebuild. They balance most of the moving parts. Do you already have a roller cam?
Fwiw the shop I worked at for 17 years,we had our own machine shop,built engines in house,built carry out rebuilds,did carry out machine work. I've never heard of anyone including balancing as part of a standard rebuild. We'd do it but that wasn't a standard rebuild.We would blueprint too,deck and square,but again extra charge services.
 

squaredeal91

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Fwiw the shop I worked at for 17 years,we had our own machine shop,built engines in house,built carry out rebuilds,did carry out machine work. I've never heard of anyone including balancing as part of a standard rebuild. We'd do it but that wasn't a standard rebuild.We would blueprint too,deck and square,but again extra charge services.
I didn't mean literally a part of one but I think it should be is all lol. I should have been more specific. I just think that if you're going to go through and spend the money then why not get it balanced while its already there because it's going only be a blessing to your engine.
 

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