383 build up (450+) hp
 

good 383 build. cast heads. decent CR. 6000rpm redline. nothing coming up through hood. 4 speed 3.55's. 4200 lbs car. headers exhaust size. for a friend he wants to know what you guys think. any suggestions thanks!:)

shouldnt be too hard engine masters did a lifter test using the 383 they claim its stock bore/906heads/ they added kb hypereutectic pistion. (9.1 comp) headers rollor rockers(1.6 ratio) M1 intake and 750 speed demon carb.and got 455.7 hp at 5800. and 457.4 tq at 4900. using a comp XE 285 HL cam and comp HE lifters

it is easy to achieve 450 hp with those guidelines
which heads would you use?

well I was thinking just somthing stock. 346's 452's 906's something. wasn't sure. HP springs. no porting a simple yet powerful build. maybe decked heads not sure. how far in the hole do 383 pistons generally sit? its an 67 or 68 383 out of an airport limo. low miles. good shape. no heads so i need to pick heads. i though i saw that it was a 300 hp motor. making big torque like upper 400's 480 or so. big numbers was shocked. Saw that in chilton. so im thinking a relative easy 450 hp. what CR and cam? street car. either a heavy E body but i was thinking for me a 69 valiant. but not sure tell me what you guys thinkg thanks!

:pistol:Shoe horn that in to a valiant! box the frame or you may be driving around with a front wheel in the air. would be a Honda killer!

72 -

Stock cam?
What do you consider a decent CR?

Archer

Stock 906 flowed in the 195-205 cfm area if memory serves correctly. And that will be a major factor in hitting your goal. You wont hit it with stock valves and flow.

Send the 906s to Muscle Motors as they have a CNC program for them to flow 300 cfm with a exhaust that flows 70 percent.

Deck block and /or heads to get your CR pump gas friendly if you are keeping stock short block.

Headers: 1 3/4 or 1 7/8 full length with 2.5 (min) mandrel bent with x-over.

If it runs mostly street use the best flowing dual plane intake you can find with that heavier weight.

There are numerous cams that will hit that mark. I prefer to look at the overlap in the transmission and its gears to find exactly what rpm the ride lives in the majority of the time and cam accordingly. This is often overlooked.

For a street fighter I never use a cam to create HP, cam the motor to dial where you want the HP and TQ to peak.