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Discussion Starter · #1 ·
I'm thinking about makin the 351c a 408c over the winter. Since my block will end up being my weak link (I'm guessing), I want to run the cast crank incase the block lets go. Since my bores are still good, I won't be hard-blocking it either. The only changes made to the engine will be the rotating assembly. The cam is a 242/244 @0.050 custom MME hyd roller so I'm guessing 6500-6800 will be the max rpm. I'd guess for a hp it would be in the 500-550 hp range ??????? The engine will always be naturally aspirated and I highly doubt there will ever be any nitrous used and primary use will be street with an occassional blast down the strip. So under these conditions, will the series 9000 cast Scat crank and forged I-beam rods hold up fine?
 

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I have used a couple for BBF and they are nice. I would use them again no problems. For 6800 RPM i would do an internal balance which you would have to do anyway for the stroker.
 

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I've seen some guys spend a lot of money for an internal balance.
Joe can correct me if I'm wrong but I thought he once said that an internal balance made no difference in power in his engines turning 7500.

Really, the cam is way too small? Could you explain why?

If you don't mind my asking Big Joe, when did you become a Ford guy?
 

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On 2006-10-09 21:03, BrianS wrote:
I've seen some guys spend a lot of money for an internal balance.
Joe can correct me if I'm wrong but I thought he once said that an internal balance made no difference in power in his engines turning 7500.

Really, the cam is way too small? Could you explain why?

If you don't mind my asking Big Joe, when did you become a Ford guy?
Internal balance isn't a power thing. It's a bearing life thing. At 7500rpm your front and rear bearings are being pounded on by 50oz/28oz imbalance counterweights with a substantial amount of leverage. This is not to mention harmonics and crankshaft flex (cranks flex, no joke =).

Far as Joe being a ford guy...he built that 400hp 302 what...7 years ago? Maybe a bit more, and I'm sure he's built more than a few high hp fords before even then =). Plus as he has said on this forum, a 347 will walk away from a 350 series SBC any day of the week. They're EASY to make power out of. Same for the big stroker windsors.

My take on the cam being too small...

That cam would make good power in the 6000-6500rpm range on a 347, all things being equal. What happens when you suddenly add 61ci to the mix. More stroke, more cubic inches, more air/fuel necessitates more duration for a given rpm.

Cris
 

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Discussion Starter · #7 ·
On 2006-10-09 21:40, Is1BadFord wrote:

That cam would make good power in the 6000-6500rpm range on a 347, all things being equal. What happens when you suddenly add 61ci to the mix. More stroke, more cubic inches, more air/fuel necessitates more duration for a given rpm.

Cris
That cam made a peak hp on a chassis dyno from 6800-7000 rpm in my 357" Cleveland. After doing a bunch of number crunching on engine analyzer pro, adding the 51 inches to this engine and retarding the cam 4 degrees, it should give me a hp peak between 6250-6500 rpms and doesn't fall off til about 7000 rpms. So if I'd shift at, lets say 6500-6700 rpm, it should run just fine.
 
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