Can anyone tell me the difference between a Pulley/harmonic balancer for a Chevy 230 engine and a 250 engine. I am not sure which engine I have and Ebay indicated they are not interchangeable. Thanks Pete
Ebay is wrong. The same balancer fits both engines, and will also fit the 292 in some applications. The 292 balancer usually has 3 belt sheaves instead of 2, and is usually of much heavier-duty construction. Both the 230 and 250 have a 2-sheave pulley with the belt grooves machined into the outer ring of the balancer. They both fit a crankshaft snout 1 1/4" in diameter, just like a 216, 235, 261, and a lot of the V8 Chevy engines.
Since both 230 and 250 engines use the same block casting, the only way to tell the difference in the engines will be to check the stamped ID number by the distributor or measure the crankshaft stroke. A 250 has a longer stroke and the same bore size as a 230. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
First off, you wanted to know what you have a 230 or 250. The best way I know is pull a sparkplug and bring that piston up to or close to TDC . Shine a flashlight in hole and look at top of piston. Flat top with valve reliefs =230 and a dish shaped top piston equals 250. If you have off set motor mounts side to side your a lucky man cause you have a 292. I believe they would fit but can affect you in different ways. Possibly the number of grooves on balancer for belts 1vs2 , timing mark on balancer ( I've seen the indicator tab on timing covers on the right and left side) which makes the mark on the balancer in a different position. I know the 250 has two different balancers. It has to do with the v groove belt spacing which is different after 1975. Hope this helps!!
Not my photos... off of 12 bolt .com. Can go to their web site and get a better explanation and additional photos of dampners. Just search harmonic dampners.
If you don’t know if you have a 230 or 260, here is a link to Deve’s website on engine identification that may help. [LINK]
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Sorry to be the wet blanket. It's not a balancer. The factory used different ones for different engines because... ... the harmonic vibration periods of similar engines varies depending on stroke length (among other things).
Panic, thanks for pointing that out and correcting me... I knew it was for vibration but also thought it was used for balancing All engines which I was incorrect. INTERNALLY BALANCED ENGINE=harmonic dampner. EXTERNALLY BALANCED ENGINE= harmonic dampner/balancer Thanks Dan
My casting number is 3921968 which doesn't show up on DEVE's casting list. He does have 3921967 which is a 64-69 230CID. My build number is CON2 E289 which translates to May 28, 1969. I also looked at the top of the pistons and they are flat so it most definitely is a 230CID.
Engines like the Windsor, BBC 454, SBC 400, Chrysler 360, etc. are externally balanced (manufacturer's preference, also possible to balance internally) using components attached to the crankshaft but outside the engine block. Generally, this is done by adding a fixed weight (Windsor dampers are 28 oz.) to a conventional flex plate or flywheel and/or similar to the damper, so that in future these weights will always be correct: the final adjustment is done by machining the crankshaft as usual. Unfortunately, placing the weight outside adds some bending motion to the crank so the consensus appears to be: use it if you have to, but for racing try to make all adjustments internally. This is where Mallory metal (Tungsten alloy) is used to make the counterweights heavier.
The 230 and 250 in theory would benefit from a different damper, but the .28" stroke difference may change the crank's harmonics so little that the same damper will be close enough to work on both.
I also looked at the top of the pistons and they are flat so it most definitely is a 230CID.
I have built a bunch of 250's with 307 V8 pistons. Those are flat tops. Unless you measure the stroke, you're still guessing. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
