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Quote:

Originally Posted by Young Performance (Post 3827610)

Depending on how the pistons and crank counterweight are cut, they may or may not clear the crank counterweights with a stock (6.135) length rod. Usually, they won't clear, so you need to go to a 6.385 or 6.535 rod with a 4.25" crank. You would also have a less than desirable rod angle(1.44) with a 6.135 rod and 4.25 crank. If you use the longer rod, then you will have to change the pistons because the compression height will not be correct. Most would use a 6.385 rod with the 4.25" crank.
Eddie

+1.

something to consider also. If your $hit's in good shape, and its power you seek, freshen it up, install some good headgaskets, a superchiller, a hyd roller cam, and up the boost a bit. If that doesnt sound like enough, sell those 256 blowers and bolt on some whipples, or 8-71s. You'll find more power there than just going up 35-40CI, for around the same money. Because at 540CI, your blowers will be smaller than they are now.

My Potter built 540 is the short deck block .030 over with the 4.25 crank and 6.385 rod, this is what most do so you are starting out with a fresh bore, the right pistons, and is a totally fresh short block.

Quote:

Originally Posted by drivrswntd (Post 3827687)

Dead on and sounds like a Bob M build up. He did the 548 tall deck I got and cant wait for spring to get it in the boat and on the water

10-4 B.M. build, we talked today about piston selection for my motors, great guy and a wealth of knowledge.

Quote:

Originally Posted by tunertech (Post 3827684)

pow :lolhit:

just make sure I out run Keegan when were done

Quote:

Originally Posted by MILD THUNDER (Post 3827693)

I failed to inform that I already have upgraded the blower to an 871 littlefield and a whipple low pro cooler. The motor is out right now and my gears are turning. Maybe it is time to just upgrade the cam to a hyd roller...going to have everything inspected and make some decisions. Wouldn't mind going to some aluminum heads either.

Some of the 575 cams had issues breaking, I know!
Go roller!

Quote:

Originally Posted by JRider (Post 3827784)

Now your talking!

Just a thought - if your 502 is running sell the long block and start over from scratch.
What's left of your old engine if you replace the crank, rods, pistons & heads?

Quote:

Originally Posted by Mbam (Post 3828415)

Just a thought - if your 502 is running sell the long block and start over from scratch.
What's left of your old engine if you replace the crank, rods, pistons & heads?

Yeah, I am leaning towards utilizing the good components I have and deciding where to go based on what my fuel injection can give. One reason I would like to keep what I have is that people tend to like merc packages...and even though this will be very thin on Merc content it is still blue. I know Zuckerman upgraded a 575 and made some pretty respectable numbers. Assuming my bores only need honing, I will keep the pistons as they are JE/merc. The crank and Hbeam are manley/merc so I if they are good after inspection I will keep them.

The biggest decision I have to make is heads. I cannot go with raised exhaust port heads due to my hatch clearance with the etops. That limits my selection of heads. I considered going with the edelbrock marine heads due to cost and hatch clearance...OR I could have Valako port my stockers on the exhaust side. Any input in this catagory would be helpful. After choosing heads the cam is next.