thedonz

I would like to re-build a 383 sbc to about 450hp. What parts should I use and how reliable should I expect the engine to be (assuming a correct build)? I probably need a new set of lifters. Should I use hydraulic roller lifters? What cam should I use? What should I use for heads? I have a Performer intake. Is it adequate?

Thanks for your help.

Frank

SB

A performer is best for a 305cid. I would never use it on any performance 383 or 350 for that matter.

Air Gap RPM - will easily support your hp wants

Good heads - AFR 195's / Trick Flow 195's / Canfield 195's / Brodix 200cc IK's or RR's / Dart Iron Eagle Platinum 200's / etc,etc. Vortec l31 max at about 400-410hp without some good porting as an FYI.

Cam - I would go with a Hydraulic Roller. The better the head the 'less cam' will be needed. And vice versa. Head chosen will determine type of cam spec's.

Compression - 9:1 to 9.5:1 max.

Exhaust - lightning or cmi headers. Not to sure anything else will support that hp level.

cstraub

Just had a customer do one for a 22 Scarab. Top speed with a 26p prop is 68 mph GPS at 5200 rpm. Best the boat ran was 56mph with a 23p at 5400 rpm.

Bottom end
Flat top forged pistons with Eagle I beam 6 rods for 9 to 1
Stef's 9qt (10 qt system) pan with stock cooler (runs 210 degrees max)
Dart 200 Heads
AirGap Intake
750HP Holley that has been marinized
Hyd roller 222/230 .560/.510 on a 112 with 4 degrees adance
Morel Hyd rollers
Lightning Headers

Engine has been in for 3 weeks now. He is on his second alpha drive build.

ratman

ive built a few, start with a 4 bolt block go .030 over for 388ci, skat makes a drop in crank for the 383 3.75" stroke. skat makes a 5140 cast crank engine parts warehouse in hollywood fl has great prices on the skat parts specify 5.7 rods so the crank counter weight ill be the correct diameter as the make a crank for a 6.0" rod also, summit reconditioned 5.7" pink rods with arp bolts, srp/speed pro pistons flat top forged, run a cyl head with 72-76 cc chambers to run pump gas, victor single plane high rise intake, 750 cfm holley, doug herbert has great prices on roller valve train, cam, lifters, roller rockers, moly 1 peice push rods. install main bearings 1,3,5, and drop the crank in the block, install the cam and a speedmaster timing chain and gears. you will need to mock up the short block to clearance for the rods. you will have to grind the block in a few places and will need to gring a couple of the rod bolts to clear the cam shaft, a small base circle cam will make it easyer, but is not a neccesity, you will be amazed at how much grunt that little sucker has! pm me if you have any questions, or round up the parts and run over to tampa for a weekend i'll help you assemble the short block or the whole engine. rm

Plane Silly

I just built one for a blower application. I used the Eagle 12106 rotating assy with -31cc pistons (8.5:1), it was right at $1500. I am using the Edelbrock Etech 200 heads because I have the Vortec intake with the fuel injection. Hp should be in the 550 range.

thedonz

thanks for all the info and advice....

phil,

how much hp do you see out of that setup? ever had one in front of an Alpha drive?

bobl

Hey Blowncrown, I just dyno'd the Whippled 383 I built. Ported Vortec heads, 3.3L whipple with 800 carb. Crane hydraulic roller, Stainless Marine exhaust. Initial pulls made 571 HP at 5500 RPM, over 600 ft. lbs. of torque at 4000 RPM. This is ready to drop in the boat with wet exhaust, sea water pump and alternator. Power was still climbing at 5500. A little bit of tweaking should get me near 600. That is with 6 psi boost.

Plane Silly

Awesome Bob!

I'm going to hit the water with mine tomorrow and see how close AZM got the tune. What cam did you use, I may need an off season project?

ratman

450-470, with a flat torque curve. the motor pulled like a locomotive from 2000 to 6500 rpms it was an animal. i used oem casting #882 sbc heads that i ported myself, added ss valves roller springs 7/16 screw in arp rocker studs. you can get a lot of alum sbc head for 1000bucks these days, with ss valves set up for roller, i would go that route on the heads, but you dont need to spend big coin on a/mkt rods and forged steel crank for the ho your want to make. i ran a solid .550 roller cam that doug herbert recomended idled great, but what torque, that thing throbbed at idle, you would have thought it was a bbc the way it pulled. go with a flat top forged slug and a larger combustion chamber, the flat tops will be lighter and less chance of detonation with fewer sharp edges on the piston crown. i psoted the number to competition product that has a stroker short block with good parts for i think it was 1800 bucks ready for your cam and heads. figure decking the block, hot tanking the block, align honing the block, squaring the block, boring and honing the block, the machine work on the block might cost you 7 or 8 hundred bucks, the assembled short block might be the ticket. do a search for cometition products ph#, i posted it here a few weeks ago for another guy wanting to build a stroker sbc, good luck let me know if you need any more info, pm me, take care. rm