SBC 427 questions

[cgarb]

Awesome...I happen to have 2 sets of Crower .904 lifters, the next generation of my 421 will have a bit more pep to it...lol. Good to know the standard base circle clears the 2" rods in an SHP Pro. I know your application is truck pulling, so I assume that is why the Callies Magnum crank. If you were building one specific for drag racing would you consider a lightweight crank...similar to the Scat F-43 that they offer in 3.875 with the 2" rod pin or would you stay with the more heavy duty crankshaft?

[randy331]

Yes, for a drag car I'd at least consider a lighter crank. Not sure it'd be worth the extra cost for most.

The Pullin truck 412 has about 60 Lbs of flywheel/clutch/pressure plate hanging on the back of the crank. It's a pull down situation. Starts out at high rpm and the sled pulls rpm down, so added weight isn't a negative. No need to take weight off the crank.

Randy

[cgarb]

I know what you are saying... lightweight crank won't make any more HP...but will accelerate quicker. I went from an 8" dampener to a lightweight 6.75" one on my 355 and it picked up...2 to 3 hundreths in the 60ft. Exactly the opposite that my dad thought would happen. He told me it would go slower...he kept saying it was like a lightweight flyweel, the heavy weight flywheel will 60ft harder in a clutch car. It was funny to see his reaction when it went faster. He couldn't explain it...lol. My dad is a very good mechanic...he knows how to fix cars well, but not the most scientific at times. I don't claim to know everything...but I'm trying to get better everyday. I've learned a good bit on here...it's funny to see the difference in the old wives tales that was thought to be truth back in the day to actual results. Dad just always did stuff...he didn't know why, but that's what his dad thought him and he didn't know why he did it that way. I'm the first in my family not to be a mechanic...I'm a machinist....and I want to build HP just like he did, but not just know what works but why it works.

[JoePorting]

A lighter flywheel/crank/damper should give better 60 foot times because it'll hook up better.

[rfoll]

OP, you didn't say exactly what your needs were. If going faster is the primary goal, a 415 will make the 383 look slow. The 3.875 crank will allow you to clear a reasonable cam core diameter, and most rods should clear at the pan.. Bore your block .030 or more to add cubes. The Dart blocks have very wide main bearing caps, and many oil pans don't fit. The Iron Eagle block is about double the cost of the SHP. The wide case requires a very expensive pan. How much money are you going to spend for 12 cubic inches?