Thread: TechInspector: 383 heads recomendation.

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If you remember that 383 I did last winter and documented here, I am pulling it back out and changing to an aftermarket head, intake, and a 4150HP carb. The carb is a 750 vac secondary thats been reworked by Pro-Systems. Why? The father in law had an accident that damaged the box truck, and he has found a deal on a 95 E-350 truck...with air conditioner. So he wants to scrap the chevy...I get my engine back. Its going to end up in my daughters 71 Chevelle Malibu. So, as far as aftermarket heads go, whats a good out-of-the-box assembled head that I can move my Crane gold rockers over to? I do not need center bolt valve covers or anything. I'll be runing a Crane HI-6R ignition, the 4150HP, and I would like to go with a Hydraulic roller cam. The car is an automatic, and I would like to keep the stall reasonable...say under 3500 RPM. With a bottom end like I did (Scat 9000 crank, Eagle I-beam rods, KB Hyper pistons, ARP rod bolts) I should be safe to about 7 grand on the tach...and if not we will fix what busts later. So Im asking for a recomendation on a Hyd-Roller cam by Crane, and what head (I want to stay pump gas...so 72cc) would I want? There are so many port vollumes available for these SBC's that I have no idea where to start! Trick flow, Brodix, Dart, World Products....Oh-My!

Remember...Im a ford guy, so playing with these GM's is out of my detailed knowledge....engines in general are not.

I saw Summit has a Brodix kit with a hyd-roller that is heads/cam/gaskets....you buy lifters and springs seperate, this kit is stated as 460HP and its under 2 grand! I would like to see 500+ HP from this thing, Idle at less than 1,100 RPM, and make as wide of a TQ band as I can. Not wanting a super peaky engine, but yet this will not be a truck engine. I dont need low end power, the tranny will take care of that as will the 3.73 gears.

Hey Larry, good to hear from you again.

I've never been a fan of high-rpm, big horsepower numbers for a street motor, preferring to build for a nice, flat torque curve. If I were going to build a motor like you're looking for, I'd be looking hard at Air Flow Research 195 cc Street Heads. They're available in 68 or 74 cc configurations. On AFR's site, click on dyno tests at the top of the page and then click on Chevy dyno tested packages. The first entry on a 383 shows and incredibly flat torque curve with a peak of 517 ft./lbs at 4,500 and a minimum of 450 ft./lbs. all the way down to 2,500 rpm's. Just call 'em up and use their parts recipe and ask 'em what clearances they used to get there. Piece o' cake!! There are also other 383 packages listed. Check 'em out.
http://www.airflowresearch.com/

Here are some other dyno-proven combos to look at. Look particularly at combos 15, 16 and 71, all using AFR heads.
http://www.ryanscarpage.50megs.com/combos1.html

I don't see any way I could improve on these dyno-proven combinations. Just use the parts they used and plug-and-play.

P.S. Also, pay attention to the fact that all these combos use a pump-gas-friendly compression ratio!!!!!!

I would agree the afr heads are the about the best on the market if you want big time performance. But you can get a package for the Vortec heads from Scoggin Dickey for under 800 dollers that includes the an Edelbrock intake, rocker arms, assembeled heads and gaskets with arp bolts. On my stock bottom end the package made close to 400 hp on the dyno. But if you just looking for the best heads go with the afrs.

One thing to consider if you go AFR, I have heard several folks saying they are having problems with oil consumption problems with some of the AFR heads. It sounds like it around the valve seals, it seems that the heads hold alot of oil at the bottom area where the valve seals are causing oil to be pulled in during the intake stroke.