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Old 09-01-2009, 07:20 AM
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Default Bearings and Damper BBC

I just picked up my winter project! Which is a new engine for my 242 Formula. Yes, I finally gave up on the built small block idea. I found a 454, 4 bolt freshly race prepped block bored .060. The new rotating assembly is all forged and balanced. The crank is a 427 GM (3.76) So basically I have a 440 ci engine. Everything is new in the boxes so I now need to assemble it. I also have a set of 781 oval ports that I will be putting on this. The two things that I'm a bit unsure of is the harmonic damper and the bearings.

The damper is a Professional Products 8" Powerforce? I've never heard of these before. The guy I bought everything from told me that his race shop/ machine shop told him that this was the damper that they used on their race engine. Has anyone used one of these before? If so was it better, worse, or on par with other dampers. Or should I just sell it and buy a fluidamper? If this is a good damper i'd rather just use it.

The next question are the main and rod bearings. There Clevite P series. Which from what I can see are there middle of the road bearings. Again, should I use these or upgrade to a different bearing.

I'm going to have Bob Madara build the cam, so I want to make sure the rest of the engine is up to what his cams are capable of.

Thanks for the input

Last edited by endeavour32; 09-01-2009 at 08:06 AM.
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Old 09-01-2009, 07:45 AM
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The Powerforce damper is made in China for Professional Products. Their stuff is low on the quality scale. If you use it you will probably be ok. Boaters don't turn their engines 8000 rpm and you're not building a long stroke engine. However, I would mark the balancer with a scribe to make sure the outer ring doesn't move. I have heard of that happening in drag cars. And make sure it is a good tight fit on the crank. If you want the best, get an ATI.

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Old 09-01-2009, 09:03 AM
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The P bearings are fine for almost all applications. If your crankshaft has large fillet radius then you need the H bearings. They have a large chamfer cut into them to clear the fillets. Some of the newer bearings are just narrower again to clear the fillets. If you are using an aftermarket crank, you will have to watch for this.
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Old 09-01-2009, 09:13 AM
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The crank is a new GM forged crank. The machine shop picked all the parts so I'm sure there the correct bearing. I was just questioning them because of the damper choice. Thanks for your help on this.
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Old 09-01-2009, 09:44 AM
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Default dampers

i have used the cheap/china made dampers before on a 454 w/a blower and havent had any problem yet.as said,mark your inner and outter shell and keep a eye on them.make sure they do not move.you should be ok.
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Old 09-01-2009, 10:18 AM
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Originally Posted by bcfountain
i have used the cheap/china made dampers before on a 454 w/a blower and havent had any problem yet.as said,mark your inner and outter shell and keep a eye on them.make sure they do not move.you should be ok.
Cool, more money for other things!
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Old 09-01-2009, 10:22 AM
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THat is going to be a cool motor. With that crank, you should be able to get some serious RPMS out of that thing. What is your comp ratio. Let that thing scream up to around 6500 or so.

It will be a cool engine.
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Old 09-01-2009, 11:28 AM
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Originally Posted by jeff1000man
THat is going to be a cool motor. With that crank, you should be able to get some serious RPMS out of that thing. What is your comp ratio. Let that thing scream up to around 6500 or so.

It will be a cool engine.
With the oval ports its going to be just under 10:1. Yea, this thing should sound great ripping across the lake at 6500 rpms.
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Old 09-01-2009, 11:32 AM
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Originally Posted by endeavour32
With the oval ports its going to be just under 10:1. Yea, this thing should sound great ripping across the lake at 6500 rpms.
Your gonna need the rpms with that ratio.

Bob will probably like that set up as well. Use a 454-o intake on those heads. Maybe have the larger valves installed also. Port out the exhaust side of those heads. They will be screamers.
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Old 09-01-2009, 12:15 PM
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Originally Posted by jeff1000man
Your gonna need the rpms with that ratio.

Bob will probably like that set up as well. Use a 454-o intake on those heads. Maybe have the larger valves installed also. Port out the exhaust side of those heads. They will be screamers.
I want to see if I can get the compression down a bit. I would rather be at 9.5:1. I'm not sure how much a thicker head gasket would help with this. If I install bigger valves I know they have to also increase the chamber size a bit to help with the valve shrouding. In which case I will loose a bit of compression. First though I need to get the engine assembled and measure the piston to deck height and then CC the cylinder chambers. At that point I can be spot on, right now all I can say is that speed pro says my pistons will have a 9.99:1 ratio with a 119 cc chamber.
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