not as experienced as some guys on here but have built a 383 (except clearance the block) and a couple 350s. Next time won't have a machine shop clearance the block after seeing it, its not very difficult. I don't see a 350 living longer at the same revs of a 383 with similar rods (its not a 327), and its a gain of a good amount of torque, and depending on how high you want to wind it significantly more hp than smaller sbc's. A 350 block with a 3.875" stroke isn't going to make as much difference from 383-> 396 as a 355-> 383 would make, plus that stroke will start losing rpm capabilites (a 4.0" stroke with 350 block is a low revving torquer) a 383 is the perfect build for a street engine, don't have too much clearancing headache, will run cool over a 400sb, and for something like you're building not as thirsty as a bb.
the first few things I noticed here was overbuild for your hp goal/min rating, odds are you're going to end up short of the mark and the engine will be able to handle the higher hp # anyway, unless you're hot lapping this on a 1/4 or are a superb tuner working on the edge of mechanical failure. I am running hypereutectic Keith black pistons similar style to what dogshit recommended. I would not use forged for your power numbers, the alum/silicone is lighter (rotating mass) and much more than enough for 450 hp. I run an eagle cast crank thats rated at 550 hp, also lighter than a forged version. My current setup is around 450-470 hp and have no fear of anything breaking.
As far as the rods thing, I disagree with using 6.0 rods in a garage built motor for longevity. Yes you have less sidewall loading but what kills home built hot rod street engines first (usually), blowing them up or wearing out the sidewalls at 130Kmiles? 5.7 rods are lighter (again with the rotating mass), and their pistons are stronger. The biggest problem with a 6.0 rod on a street motor is they dwell longer at TDC, and would be affected by detonation quicker than the 5.7's. Plus 5.7 rods may be cheaper if you buy through the right source.
For the best bang for the buck + lightweight rotating mass, go cast crank, hyper. pistons, 5.7 rods.
Now for the top end, you'll need heads with at least 180 cc intake runners that flow at least 230 cfm at .5 intake lift. I would look into the 185-195 cc intake runner range with something that flows around +/- 250 cfm. This is limiting you to a dozen or so aftermarket heads (unless you really want to work over some stock vortecs, it'd prob cost about the same for what you're wanting). But for your power numbers don't dwell on flow ratings alone. AFR's are nice, but you can buy something 600-700$ cheaper that would flow MAYBE 10-15 cfm less across the board at your useable rpm range. We're talking max 10-25hp for the engine you want. not worth the extra 600$ IMO. I would have previously recommended patriots, but after the cluster**** I've had with valvetrain geometry on these things I'd say go with another high quality (not pro comp) aftermarket heads, aluminum saves a ton of weight. Trick flow/dart/brodix make good heads in that range. The problem is there just isn't another new aluminum aftermarket head in the 190-195cc runner cnc patriot freedom series range, others that are more expensive generally flow less until you get to the big boys like AFR or CNC'd (that started from) 185/190's runners from other companies and thats way out of the same price range. I see one thing you liked, the 210's --- don't do it. That is not anywhere in this build equation. If you're dead set on 210's then explain what you REALLY want out of the engine. Combustion chamber depends on other things, but in general a 68-72cc chamber will be in a solid compression range for n/a pump gas.
For longevity and reliability, a hyd. roller cam is the way to go. shouldn't really even be talking about the cam until you've got the rest of the pieces together esp your choice of heads.
the first few things I noticed here was overbuild for your hp goal/min rating, odds are you're going to end up short of the mark and the engine will be able to handle the higher hp # anyway, unless you're hot lapping this on a 1/4 or are a superb tuner working on the edge of mechanical failure. I am running hypereutectic Keith black pistons similar style to what dogshit recommended. I would not use forged for your power numbers, the alum/silicone is lighter (rotating mass) and much more than enough for 450 hp. I run an eagle cast crank thats rated at 550 hp, also lighter than a forged version. My current setup is around 450-470 hp and have no fear of anything breaking.
As far as the rods thing, I disagree with using 6.0 rods in a garage built motor for longevity. Yes you have less sidewall loading but what kills home built hot rod street engines first (usually), blowing them up or wearing out the sidewalls at 130Kmiles? 5.7 rods are lighter (again with the rotating mass), and their pistons are stronger. The biggest problem with a 6.0 rod on a street motor is they dwell longer at TDC, and would be affected by detonation quicker than the 5.7's. Plus 5.7 rods may be cheaper if you buy through the right source.
For the best bang for the buck + lightweight rotating mass, go cast crank, hyper. pistons, 5.7 rods.
Now for the top end, you'll need heads with at least 180 cc intake runners that flow at least 230 cfm at .5 intake lift. I would look into the 185-195 cc intake runner range with something that flows around +/- 250 cfm. This is limiting you to a dozen or so aftermarket heads (unless you really want to work over some stock vortecs, it'd prob cost about the same for what you're wanting). But for your power numbers don't dwell on flow ratings alone. AFR's are nice, but you can buy something 600-700$ cheaper that would flow MAYBE 10-15 cfm less across the board at your useable rpm range. We're talking max 10-25hp for the engine you want. not worth the extra 600$ IMO. I would have previously recommended patriots, but after the cluster**** I've had with valvetrain geometry on these things I'd say go with another high quality (not pro comp) aftermarket heads, aluminum saves a ton of weight. Trick flow/dart/brodix make good heads in that range. The problem is there just isn't another new aluminum aftermarket head in the 190-195cc runner cnc patriot freedom series range, others that are more expensive generally flow less until you get to the big boys like AFR or CNC'd (that started from) 185/190's runners from other companies and thats way out of the same price range. I see one thing you liked, the 210's --- don't do it. That is not anywhere in this build equation. If you're dead set on 210's then explain what you REALLY want out of the engine. Combustion chamber depends on other things, but in general a 68-72cc chamber will be in a solid compression range for n/a pump gas.
For longevity and reliability, a hyd. roller cam is the way to go. shouldn't really even be talking about the cam until you've got the rest of the pieces together esp your choice of heads.
