My first pump gas 400 stroker 511 C.I. motor ended up needing four sleeves in it, two due to the block being blown out on the deck surface between # 4 and 6 and two on the other side(#1 and #7) due to bad pitting that boring it to 4.375 wouldn't clean out whiney
I already had the 6.800 long BB Chevy type H beam rods and custom forged Ross dished pistons along with the Ohio Crankshaft CO 4.25 stroke low deck crank and I couldn't find another good 400 block so I went with having four ductile iron sleeves installed and I never regretted doing that boogie I also had a set of Mopar brand Ductile iron main caps installed with ARP main studs up
I beat on that motor from day one and it exceeded all my expectations and never let me down, Fast TOO devil
One of the past members on here, R.I.P. Dan angel couldn't, wouldn't believe me when I posted the first dyno testing results when that motor had a set of ported with big valves BB 906 heads with 9.25 to 1 compression ratio and was 511 C.I. with a low deck eddy six pack set up on it. That combination made 612 HP at 5500 RPM and 644 Ft. Lbs. torque at 4500 RPM on CA 91 octane pump swill boogie
I ended up changing to four different sets of heads and ended up changing the crankshaft from the original 4.25 stroke to 4.300 stroke to raise the pistons up from -.025 down to zero deck to raise the compression from 9.25 to 1 to 10.29 to 1. I kept the same block,cam shaft, rods and pistons and I swapped the heads and intakes only after the crankshaft change the second year.
It ended up with a set of Indy SR Max wedge port size heads and a Indy 400-3 intake with a 1050 CFM Holley 9375 non HP Dominator carb. on it which made 727 HP at 7000 RPM on a DTS engine dyno on 92 octane Oregon pump swill in Klamath Falls, OR which is at 4300 ft. altitude devil
I now have several other 400 block stroker motors that I built and I'm looking forward to using on the street and at the track up
BTW, that motor had a custom ground Com Cams solid roller cam that liked to RPM, I have shifted that motor with the 440 type heads and six pack at 7800 RPM and it wasn't slowing down on the RPM gain per second in second gear shock I ended up trying to shift it between 7000 to 7300 RPM from then on up
That stupid motor didn't follow any of the normal rules for six pack motors, but it wasn't a normal six pack motor either devil boogie
Don't be afraid to experiment up twocents

Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)