Thread: HELP - Underdesigned 383

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My new street rod is a Chevy powered Mercedes. Been out of engine building for a few years so I relied on tech info from my local speed shop. I think the specs are to soft for what I want to do, so here goes : 3,700 # car, 700R4 trans, vette 3:73 rear, 27.5" tall tires. Now, the good stuff, SBC 383c.i. w/ 5.7 rods, edlebrock alum heads, performer 170cc runners, 72cc, 1.60 / 2.02 valves, Air Gap dual plane intake, Race Demon 650, flat top pistons, 10:1, 1 5/8" headers into long collector w/ crossover and 2 1/4" pipes. I saved the cam for last cause its not in yet. The car will be a street rod that will only see the strip once or twice. For street use I want all low end torque, even if I`m done by 5,500. The cam can be hyd. or solid roller, and I`m guessin about 220@50 / 525 lift and 106 centerline for rumpity rump. I want a rocket street toy but I think that the heads might be too lite. Short block is done and I have the other parts, less cam. I`m willing to change or modify if needed . Whats the right answer for my setup? I`ve got pics of the engine and car if needed. Thanks drm184 ( drm184@bellsouth.net )

If you want to see a magical combination for low end torque, see Combo 11. here....
http://www.ryanscarpage.50megs.com/combos2.html

That same cam will work with 10.0:1

Call these guys up and ask about the other specs on the build. Bearing clearances, deck height, head gasket used, etc.
http://www.airflowresearch.com

The reason cams go rumpity rump is beacuse they are barely making enough torque to keep the crankshaft turning. Get a cam ground on a 110 degree center for torque. In the Comp Cam's Xtreme Energy line, they have a grind, XE262H which is just starting to get pretty rumpity rumpity on a 350 which means it will be a little smother on a 383. I recommend you go 1 size up, but no more than 2 if you want lots of torque. I just built a 350 with the XE256H cam and it makes more torque than the stock cam everywhere in the rpm range but also extends the useable rpm range to almost 5500 rpm which is your goal. The 262 and bigger cams will have you running 6000 or 6500 rpm redlines to take full advantage of their powerbands. The Comp Xtreme Energy and I believe Crane Z product lines all use faster valve opening rates to maximize torque for a given duration meaning more hp and better driveability.