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So I decided to get a a stroker kit to put in, and right away I decided to get all forged and balanced parts. But now that I think about it, I'm wondering if forged pistons and rods with a cast crank will be ok. What do you guys think?

the top of the block will have AFR 185 heads, an edelbrock RPM II manifold, and a comp cam--- .550 lift with a range of 1600 to 6200. How much power will this make and can a cast crank handle it? THANKS!!
 

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I have actually heard there are some advantages to cast vs. forged at certain applications.

TWO THINGS: 1. Keep the RPM's under 6500 2. DON'T Dentonate

Zero foregiveness in cast.

GO BIG!! Get the 347. Get the free HP.
 

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the only disadvantage that I've heard of with the 347 vs the 331, is that the pin lies marginally closer to the top of the piston and this can make the piston slightly weaker and sometimes it can also cause oil loss issues. What are advantages of cast over forged besides price?
 

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the only disadvantage that I've heard of with the 347 vs the 331, is that the pin lies marginally closer to the top of the piston and this can make the piston slightly weaker and sometimes it can also cause oil loss issues. What are advantages of cast over forged besides price?
Reggie is gona have something to say about that. If you buy a quality kit and have it put together correctly a 347 will not have these issues. Might as well go bigger...but it is your choice.
 

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theyve pretty much have corrected all of the old 347 issues.

i say go 347!!
 
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the only disadvantage that I've heard of with the 347 vs the 331, is that the pin lies marginally closer to the top of the piston and this can make the piston slightly weaker and sometimes it can also cause oil loss issues. What are advantages of cast over forged besides price?
Reggie is gona have something to say about that. If you buy a quality kit and have it put together correctly a 347 will not have these issues. Might as well go bigger...but it is your choice.

Those issues have been corrected in 99.9% of all 347 kits sold today......

I highly recommend ProPower as a source for your kit......

Pro Power : The engine parts professionals :
 

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the only disadvantage that I've heard of with the 347 vs the 331, is that the pin lies marginally closer to the top of the piston and this can make the piston slightly weaker and sometimes it can also cause oil loss issues. What are advantages of cast over forged besides price?
Just ensure you have the 5.315 rod in the 347 kit and you will not have a wrist pin intersecting the piston issue.

If you are planning down the line seriously racing and spinning past 7,000 then go with the 331, as it has a better rod ratio and ring package, and will actually out perform the 347 in the 7,000+ rpm range.
 
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Just ensure you have the 5.315 rod in the 347 kit and you will not have a wrist pin intersecting the piston issue.

If you are planning down the line seriously racing and spinning past 7,000 then go with the 331, as it has a better rod ratio and ring package, and will actually out perform the 347 in the 7,000+ rpm range.

If you plan on any small block ford spinning past 7000

Plan on going with and aftermarket block also......:)
 

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fordstrokers.com

Highly recommend fordstrokers.com

Woody builds s good product and stands behind his work :bigthumbsup
 

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Cast... what material? There's several materials considered cast. To save money, you could go with 5140 cast steel. It's stronger than a stock crank but not as pricey as 4340. By the way, 4340 forged is a waste of money if you #1 aren't going to be seeing 6500 rpm+ on a consistent basis, #2 putting out over 550 hp, and #3 if you're putting it in a stock block. If you're limited by the stock block, the stock internals can withstand it.
5140 cast steel is plenty strong, good up to 550 hp, and is more than enough for most street engines. 4340 is expensive and heavy as a boat anchor. If you don't need it, don't get it.
 

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Discussion Starter #11 (Edited)
Cast... what material? There's several materials considered cast. To save money, you could go with 5140 cast steel. It's stronger than a stock crank but not as pricey as 4340. By the way, 4340 forged is a waste of money if you #1 aren't going to be seeing 6500 rpm+ on a consistent basis, #2 putting out over 550 hp, and #3 if you're putting it in a stock block. If you're limited by the stock block, the stock internals can withstand it.
5140 cast steel is plenty strong, good up to 550 hp, and is more than enough for most street engines. 4340 is expensive and heavy as a boat anchor. If you don't need it, don't get it.
So with AFR 185 heads, Edelbrock RPM II intake, and .550 lift cam (1600 6000rpm) would the power output be low enough (never thought I'd ask that!) to use the 5140 cast steel crank on the stock block?
 

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Yup, the 5140 is plenty strong and if it's balanced along with full preparation (knife edge counterweights, chamfered oil holes and cross drilled, fillet radius), you shouldn't be able to break it unless you're trying to. The block would break before the crank will. Plus 5140 is about 1/2 the price of 4340.
 

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Discussion Starter #13
Just ensure you have the 5.315 rod in the 347 kit and you will not have a wrist pin intersecting the piston issue.

If you are planning down the line seriously racing and spinning past 7,000 then go with the 331, as it has a better rod ratio and ring package, and will actually out perform the 347 in the 7,000+ rpm range.
I remember hearing that a rod ratio that is too low (such as what you might have with a 347) then the piston might start digging into the side of the walls, this of course can be fixed with a longer rod, but the longer rod starts moving into the neighborhood of the oil ring. So both cases have longevity issues right? I want the engine to live for 10's of thousands of miles.
 

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We're talking .085 of an inch difference in length of the rod. That shortness difference is not significant enough to worry about an increase in side loading, but having a piston pin intersecting an oil ring landing IMHO does cause for some worry. Your choice. Good luck with your project.
 

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I personally say the 5.315 rod is better than the 5.400, they seem to do better overall in terms of durability.
 

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I don't agree with the 'durability' arguments, but all I'm going to say is that there are TONS of reasons to have durability issues.
I've known crappy engine shops that would blame the parts being used, rather than fess up to their lack of knowledge/skill....


FordStrokers.com would be where I would go. Talk to Jim and see what he thinks for your application & goals.
He does offer balancing on his kits. He can also ship you a fully machined block, rotating assy, and all other components needed to assemble your engine yourself.
Or just let him build it...


Rich :wavey
I'll call this afternoon :bigthumbsup
 
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