Is something up at Scat?

replicaracer43 said
Yeah, but in my opinion, I dont see any real advantage over the 4" stroke, and it also increases rod angle, thrust load on the cylinder and a shorter piston comp height. Most ALL of the stroked sbm builds are cylinder head limited anyway. But again, that's just one guys opinion!

Cylinder head has always been the Achilles heel made worse by huge stroke.

Icetech said
You are the first person to give me a legit answer to that question :) Everyone acts like 408 over 390 is a MASSIVE difference.. but 408 to 426 doesn't matter at all.. but without much backup as to why.

Thanks :)

A lot of racers have spoken on the 3.79 being better. I’ve never really seen them explain why but I did take it with a grain of salt since sometimes the racers aspect isn’t the same as the next guy looking for big cubes.

cpearce said
If I'm not mistaken, with the additional stroke to make the 426 sb the rings are up into the wrist pin area, requiring support rails, possibly not ideal for a car that is driven. As @replicaracer43 has stated, less than optimal rod angles, short piston, side loading, and limited cylinder head architecture. If you have ever been in a 408 without W2, W5, Indy, or seriously worked standard port LA heads, they nose over fairly quickly in the high 5, low 6000rpm range. If you add more cubic inches the rpm limitations become more pronounced. Something that can't be measured on a dyno is an engines rate of acceleration, when strokes get very long, engines don't gain rpm as quickly as one with a shorter stroke. Though I don't really race, I've seen at the track where shorter stroke engines can get off the line quicker than some of these really big stroker. I feel the 408 is a nice balance with good heads.

This is the street guy perspective IMO. While there is a advantage to a larger stroke crank for the street guy because there thinking more power to be made at a lower rpm which equals less rpm stress, this also may not be as true as they think. While being accurate, it’s not what most think it’ll be.

I still want to do a 434, or larger. I don’t expect it to be a few things. Things like;
Cheap
Effective
Longevity
Fast in the car because huge cubes isn’t everything.

I do expect a ridiculous amount of tire burning torque even with a numerical low gear set.