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by the time you get it balanced and finished you will have spent enough for a forged crank..





EXACTLY........

Few years back i broke a cast 4 inch stroker crank. I had upgraded my combo from high 10's to 10.30's and it broke after about 50 passes, and ruined the rest of my season. I learned the hard way to do it right the first time.

Like i love saying, spend the extra 500 bucks and get the good piece the first time. In the whole scheme of building a motor, 500 bucks is just a small fraction of the total build, so why scrimp, just wait till you can do it right, then you wont ever have to wonder




to the cast crank's credit, B422W5, how many years did you run the cast crank, externally balanced in your 3400lb duster running 10.75-10.80? IIRC yours was a MP crank, which was made by SCAT...and I'd imagine your drag strip launching with slicks and a high stall converter would be as brutal, if not more so, than street driving a 4 speed with street tires.

as far as factory cast vs. SCAT 4" cast, hotroddave makes some good points, although the factory cast cranks are ductile (nodular) iron, so the continuous phase of the material is steel, not graphite, like it is in grey cast iron. the lack of filleted radii is offset by the fact it has more journal overlap due to the shorter stroke.

if you have no plans for further upgrades, I'd just run the cast crank, or even if you do have plans for further upgrades, it might be more cost effective to build a whole new motor in the future, because soon you're going to get close to the limits of the factory block....





Actually, i didnt run that cast crank as long as you seem to remember.

I had the 416 built by Hensley, very mild. Ran it first year and it went 11.70's without that many passes at all. Over the winter upgraded a few things and it went 10.70,and 80's. The third season i put w5 heads on the shortblock and it let go( flat tappet, 11.8 compression. I probably had 150-170 passes on it when it let go that third year part way through. And as i said the first year it was ultra conservative. So not that many passes with real good power, and a good bit without much power at all( 500 horsepower maybe)

My point is, spend the money and get a good crank, and only have to do it once.

BTW, ALL the above passes were off the foot without a 2 step. I only went to a brake when i put the X block roller motor together after the crank broke in the above 416.


69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight
418 BPE factory replacement headed stroker, 565 lift solid cam
Best so far, low 10.30’s 1/4
1.41 best 60 foot
6.56 at 104.17