[DeTomaso] 351C Crankshaft Question

[JDeRyke at aol.com]

In a message dated 9/26/08 9:23:10 PM, tonydigi at optonline.net writes:

> One more time on a common debate:  For a stock-displacement Cleve of 10:1 
> compression for occasional track and street use, do we prefer a stock crank, 
> cast steel crank, or forged crank????
> 
First, I suggest you call a real race engine builder-with a reputation for 
quality- and spend an hour picking the brains of a guy who does this for a 
living. Most of us build 1 or 2 engines every now 'n then- hardly a good reference 
point. Having said that, you're talking about a mostly-stock engine and the 
stock crank is the toughest part of a 351-C! Seldom does one fail; even if you 
manage to spin a main bearing, the thing can be reground up to 0.030" smaller 
without compromising strength, or if you really like THAT particular crank, it 
can be weld-repaired and reground back to stock size. I wouldn't worry about 
using a stock crank until you get up to over 500 rear-wheel horses (around 600 
at the flywheel), unless you have a big stroker, very high rpms or some tricky 
lightening work in mind. I'd suggest a good set of aftermarket con-rods and 
ARP rod bolts, though.
As for external balance vs internal, again don't bother until you get above 
500 RWH. Internal balancing tends to allow longer main-bearing life and less 
crank-twist during steady over-6500rpm running but you gotta have an engine 
powerful enough to twist it! A good std balancing by a specialist will pay off 
big-time in smooth running and long bearing life. IMHO there are many more places 
to spend $2000 than on a trick steel crank for a 400-horse street engine- 
which will be plenty exciting, believe me. Stock was around 275 real horses at 
best. Good luck, Tony- J Deryke



**************
Looking for simple solutions to your real-life financial 
challenges?  Check out WalletPop for the latest news and information, tips and 
calculators.
      (http://www.walletpop.com/?NCID=emlcntuswall00000001)