Harmonic balancer
Melting Slicks
Joined: Feb 2011
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From: Middletown Ohio
2016 C1 of Year Finalist
Thread Starter
Race Director
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From: Cottonwood AZ
C1 of Year Finalist (performance mods) 2019
Google Fluidamper or www.fluidampr.com/what/
See what they offer.
See what they offer.
Thread Starter
Race Director
Joined: Nov 2003
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From: Cottonwood AZ
C1 of Year Finalist (performance mods) 2019
My engine will be internally balanced as I stated earlier. Are you suggesting I need an 8" balancer? My rpms will seldom if and exceed 6000.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
'55-'56 pass balancers had the belt pulley riveted to the balancer as part of the assembly. Don't know about Corvette. Best I can do.
Melting Slicks
Joined: Feb 2011
Posts: 2,892
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From: Middletown Ohio
2016 C1 of Year Finalist
6 1/8 inch balancer.
68Hemi
The original balancer off my 283 HP 283 FI engine is 6 1/8 inches in diameter.
Should be the same on the 270 HP engine.
Second pix shows actual dia measurement.
See attached pics.
I might have a spare, if you are interested in it I will hunt for it.
Bruce B
The original balancer off my 283 HP 283 FI engine is 6 1/8 inches in diameter.
Should be the same on the 270 HP engine.
Second pix shows actual dia measurement.
See attached pics.
I might have a spare, if you are interested in it I will hunt for it.
Bruce B
Last edited by ohiovet; Mar 21, 2017 at 12:05 PM.
Race Director
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From: CT
Don't know about the Corvette 57, but I have a '57 Belair with power pack and the balancer is very small, about 6" and it is one piece (no rubber inbetween. i image that would be a very bad set up for your purpose. My 70 LT-1 engine in my '62 has an 8" balancer.
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Le Mans Master
Joined: Feb 2012
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From: Glen Allen VA
Yes, and I am looking at the web site of Fluiddampr for one and they list several that are for small block and they are different sizes, hence the question about the original size for a 57 270 h.p. balancer.
My engine will be internally balanced as I stated earlier. Are you suggesting I need an 8" balancer? My rpms will seldom if and exceed 6000.
My engine will be internally balanced as I stated earlier. Are you suggesting I need an 8" balancer? My rpms will seldom if and exceed 6000.
Thread Starter
Race Director
Joined: Nov 2003
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From: Cottonwood AZ
C1 of Year Finalist (performance mods) 2019
So, am I correct in assuming from all of this that an original type 6 1/8" balancer should be fine on this 383 stroker as long as I keep it under 6000 rpms?
Race Director
Joined: Nov 2000
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From: Beverly Hills (Pine Ridge) Florida
May be splitting hairs here, but it is of no consequence that your engine is internally or externally balanced. The "balancer" has no affect on bringing your engine into a balanced operation. This "balancer" is not a "balancer" in the rotational sense, but rather is a harmonic damper. It's purpose is to absorb and lessen the torsional flex in a crankshaft to prevent fatigue failure.
And that the 400 crank (3.75" stroke) is what is used in 383 engines (some with different main bearing diameters, but most with the same basic balance configuration).
And that most 383 CID engines are externally balanced, and require that offset balancer (plus offset balance flywheel or flexplate) be used, or they will shake themselves to death in short order?
Plasticman
Last edited by Plasticman; Mar 21, 2017 at 02:49 PM.
Team Owner
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From: Greenville, Indiana
I'd again advise you to contact an expert for your needs. I'd be surprised if anyone on this forum has the technical background to make a specific recommendation but I could be wrong.
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
The link AZDoug posted
http://www.bhjdynamics.com/index.php...ek8av8l1d37od7
Le Mans Master
Joined: Feb 2012
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From: Glen Allen VA
Are you aware that Chevy 400 CID engines used an offset balance (special) balancer?
And that the 400 crank (3.75" stroke) is what is used in 383 engines (some with different main bearing diameters, but most with the same basic balance configuration).
And that most 383 CID engines are externally balanced, and require that offset balancer (plus offset balance flywheel or flexplate) be used, or they will shake themselves to death in short order?
Plasticman
And that the 400 crank (3.75" stroke) is what is used in 383 engines (some with different main bearing diameters, but most with the same basic balance configuration).
And that most 383 CID engines are externally balanced, and require that offset balancer (plus offset balance flywheel or flexplate) be used, or they will shake themselves to death in short order?
Plasticman
Race Director
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From: Eagle, Idaho
I am starting with a bare block that is currently at the machine shop. It will be balanced and blueprinted. The intention is to create an engine that looks like an original 270 h.p. engine. I want a balancer that will appear the same as the original 57 hi lift cam engines. I have ordered the deep groove pulleys as these engines had as well. I already have the balancer/crank spacer. I need to know what balancer and timing cover spacer to buy to go with this stock look.
Safety Car
Joined: Oct 2016
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From: Olive branch Ms
The short answer is yes you'll be fine running it. You are getting some less than great advise here. Now days most 383s are internally balanced. I would hope you went with a steel crank. If you use the best most expensive damper or the stock one you'll never know the difference. As far as technical experience been building race motors for 43 years. I've built tons of SBCs that run above 9,000 for extended time. I use an elsatomer type balancer, ATI, they're on pretty much all NASCAR engines never seen anything else on one. Sprint cars routinely run that kind of rpm and they don't even have a damper on them. A stock type damper will be fine for your app. Ask the guy doing your work if you don't trust his advise well!!!!!!
Team Owner
Joined: Mar 2003
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From: Greenville, Indiana
By all means, ask the guy with the greasy rag in his back pocket!
Do you realize the OP is building a street engine and not a race engine? Two totally different animals.
Race Director
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From: CT
Chev used different sized and different weight balancers on the small block engines for a reason. Stray too far from the "reason" and you will be posting "why did my engine go bad"
Safety Car
Joined: Oct 2016
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From: Olive branch Ms
During the 70s I built heads that won several NHRA US Nationals in S/S. In the 80s for The same company I headed up the street engine department hiring and training enough people to build 2,000 street engines per year for a total of 6,000 engines while I did that. From then til the early 90s I ran my own shop where I actually balanced engines. And now your turn. I am finished with this thread now as the one thing I do know is if you wrestle a pig in the mud long enough you figure out the pig likes it!
Race Director
Joined: Feb 2004
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From: CT
During the 70s I built heads that won several NHRA US Nationals in S/S. In the 80s for The same company I headed up the street engine department hiring and training enough people to build 2,000 street engines per year for a total of 6,000 engines while I did that. From then til the early 90s I ran my own shop where I actually balanced engines. And now your turn. I am finished with this thread now as the one thing I do know is if you wrestle a pig in the mud long enough you figure out the pig likes it!