Thread: 396 Block and a 454 Crank

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I know there's been threads about this before, but I just want some more input. I've already decided I'm going to do this, both because the casting numbers are fairly close to my car, and my great uncle gave me the 396 for free as long as it goes in my Bel Air. The engine is a 325hp 396 from a 1966 Impala with a TH400 automatic. A guy that drives truck for my dad did the same combo in his 1970 Chevelle and he's really happy with it. For the long block, I'm going to do the 454 crank, with ARP main studs, and I've heard there's some KB pistons that make up the difference in stroke. I think I'm going to use the stock heads and port and polish them. I'm not sure what I'm going to use for a cam, but I think I'd like to use a Comp mutha thumpr roller cam and Comp roller rockers. Just wondering if anyone has any tips.

kb makes a piston in a hyper s . you do not need main studs on a bbc for this power level .if you use studs you will have to check the main bore of the block should be checked any ways .made 600hp+ with the stock gm bolts many times for many years there 1/2 inch never seen one fail ever and they fit and clear the oil pan were the nut and washer can hit and if you buy the kit for the windage tray you are going to have to trim the studs they will hit most all oil pans .GM bolts/ stand offs for tray fit and work like they should make sure there for a lV block as the Vl are longer bolts . do not do much on intake runners .do not port /polish the heads..it.s not needed . some bolw work chamber work with better flow ss 11/32 stem valves will be all you need . i do not use thumper cams.but yes on a hyd roller cam. this is the short list .oh check back cam bearing on that 66 block you may have to have a groove on number 5 so you get oil to the lifters and top end

Just curious, why wouldn't you polish the ports? The number 5 journal on the cam has a groove in it, so I'm guessing the bearing doesn't have one? I suppose any aftermarket cam I get isn't going to have a groove

Originally Posted by Dieselholic92

Just curious, why wouldn't you polish the ports? The number 5 journal on the cam has a groove in it, so I'm guessing the bearing doesn't have one? I suppose any aftermarket cam I get isn't going to have a groove

polishing the ports is not going to do any thing . do you have any idea whats going on in the head ports . smooth intake ports do not help mix fuel . i can get more power out of a set of heads with 4to 5 angles on the seat and a full radius cutter on EX and some bowl profilers then some hand blending . then you are going to get playing around with the ports. cut out the short side radius of the heads you will have junk. the bbc ex side there is not much short side to screw with. do if you want knock your self out .if you never done set of heads you do not want to hit the seats or open this parts of the head up or you will have junk or the machine shop will have to put seats in the heads or sink the valves and thats not good . the heads really do not need alot of work to make good power there is some things that well help to a point then its better to look at some AFR s or Brodix Race Rites .or RHS . or Pro fillers .all are good heads but you have to watch port runner size on this build . small O port is all you need . the block it.s self #5 is not grooved like 67 till 89 so the cam needs the groove for upper oil that feeds the lifters and top end . your block would be 65to66 . the cam can be cut if the machine shop has a lathe or cam can be done at the company that you buy the cam from.your block has no dowel pins to line up the front timing cover and the block has a dist tower casted in the block as well. done many