Kinda slow today been doing some thinking. I run a 410 stroker small block. It has edlebrock heads that other than valve springs, retainers and milling to 59cc's hasn't been touched. I have been running a M-1 that has some port work. I run a solid cam in the .555 lift 296 dur area with a lobe cent of 108. I have been shifting at 6600 and tach at 6900 in the quarter. I have been worried about the cast crank at these rpms and since the engine peaked at 525hp @ 6200rpm on the dyno maybe I'm twisting her too tight. I have a dual plane that is supposed to be good to 6500 rpm and I doubt the heads flow much more over than anyhow. Would I be ahead shifting at 6200 and running the dual plane and my 4.10 gears back in? I am running 4.56's now with 29.5 mickeys. Car runs good now I'm just concerned about the Eagle cast crank.

Thanks
Gary

Only way to know for sure is to try it, I don't think the dual plane will make more power than the M1. 4" stroke small blocks need more plenum size then your typical 340 or 360. You could always short shift the car, it might slow a little, but would help with longevity. I'd say leave the motor alone, try the 4.10's if you're worried about the crank at current rpm's.

Before I changed anything I would start shifting at 6000 rpm and go from there. If the car will run about the same times at a lower rpm I would leave it there. If you are bracket racing I would leave it at the lower rpm anyway just to help the engine survive longer.

Move the shift points up on each gear change to lower the top end RPM at the finish line Try 6900 RPM instaed of 6600 RPM

You wasting the motor away turning that many RPM.

Try the 4.10s first and shift mabey 6500 max and you will probably pick up everywhere except mabey 60ft, if you want that back try the dual plane and a 1 inch spacer. All that should help the motor last longer also.