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63 421 help

08/16/2020 23:17
FIRSTLAST
I am slowly working toward a 63 421 using 455 crank, ported 9770716, a head that flows well similar to s SD 980 set. Anyone be able to help me out a number on a pretty stock combo? I may need to get the block evaluated to give you an accurate bore dimension. It is clean, should be no more than .030 over, but that is only a guess. What am I lacking to plug this into a HP calculator?
08/16/2020 23:19
FIRSTLAST
The question was HP?
08/19/2020 11:24
FIRSTLAST
Getting a 450 HP answer running a roller cam. Any experts out there watching?
08/19/2020 12:00
ASHLEY P
"What are you lacking..." A LOT of info. Head flow, cam spec, CID are the basics. I'd suggest not getting focused on a HP number. Just look at how heavy your car will be and how fast (MPH) you want it to go. Then look at prior builds that accomplish similar goals.
08/19/2020 17:02
FIRSTLAST
The HP is for my carb builder, making the factory correct dual quad setup. I am constrained, correct block, heads, intake, carbs. Flow opened up to very close to the Super Duty 980 heads. I haven't got the flow data on my heads, but can access from articles. My heads have been in the machinists shop for a really long time. Have to be patient, the work is good and they are expert. He has the background and builds champion cars. This car will only be able to get bore stroke and cam changes. So I thought 455 crank unless I go to a Chevy crank 462? The 421 block is nice, building for street and durability, so prefer only .030 over. Engine will produce vacuum, need driver amenities, so no race radical stick lacking overlap in duration. I will put 2500 miles a week on this, seeking a combo and O.D. for trans. to sustain the long drives. I can still get some decent track times with those limiitations.
08/19/2020 17:21
ASHLEY P
Are you allowed a roller cam? IF so, are you going to use a roller cam?
08/19/2020 23:24
FIRSTLAST
Yes, going with roller cam.
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