Would you guys chime in with your opinions for my 383 build? I'm beating myself up over this and I could use some first hand knowledge. My original goal was 450hp/500tq after looking at a Chevy High Performance build on the internet, but after realizing thats probably trying to take it too far, I'm now shooting for more like 400/440, with peak torque coming in early (like around 4k rpm).

This is for a 70 Chevelle that is driven often, will never see a drag strip, and will have a 12 bolt posi with 3.31 gears and a TH350. I also want to make sure that my power brakes work just as good when I'm done.

Here's what I have so far:
88-90 one piece block, .030 over, zero decked
Eagle 383 cast rotating assembly, dished hypers (advertised at 9.7 -1)

My next decision is the toughest for me, the heads and cam combo. I've had my eye on this setup:

Lunati Voodoo 60103:
268/276 227/233 .489"/.504" 110/106 Hyd/Hyd 1800-6200
Description- Hydraulic: The most awesome "268" cam ever produced Out-powers all others This High Performance street cam likes 2400 RPM stall, 700 cfm carb, dual plane intake and headers. Makes un-equaled power to 6200 RPM with proper valve springs. If you're looking for a Very Strong cam with great street manners for your "Crate Motor" this is it Factory EFI motors need custom chips/tuning.

But I'm still confused on which heads I should be looking at. Should they be 2.02 valves or 1.94? Which size runners would be best? Again, this is for a street only Chevelle that will not need to rev to the moon, and I would like at least the peak torque to come in somewhere in the 4k range.
Thanks in advance-

I know you want to talk about the 383, but I am in the exact boat you are in. I wanted about the same power. I think you should consider, as I am, going with a 406 stroker. It is much more likely to get 450/500 out of these motors, or at least this is what Im told. It should also be able to be done for about the same price and little more work clearancing. If not good luck with your 383, I still might go down that road.

IMO with a 383 you should get 2.02/1.94s and 200 cc runner.

What kind of heads are you looking at? Have you considered retrofit hyd roller?

If it's just going to be a street only car, why bother with the expense of the 383 and 400 hp? You'll never be able to use the full potential of that motor on the street, especially those specs. The 60103 is a great cam with wonderful street manners, in fact you can't even tell my BB has a cam in it running that same cam. Can't go wrong with the 2.02's IMO. I'm not a big SB guy so can't help you with the part numbers here on the heads. good luck JN

for heads i would look into a placed call tristate cylinder head based out of indiana. I got a set of aluminum small block heads with 190cc runners and 2.05 valves and they are great....i think i got them for $800ish

Why do you think 450hp is so far off for a 383?

I have seen alot with 450hp and more, yes they are more radical but its not like it cannot be done.

http://www.pro-formanceunlimited.com/specs/383_350_economy.html

http://www.enginefactory.com/Stroker.htm

http://www.dallasexportsales.com/383485TK.htm

http://www.guaranteedengines.com/shopcart3/Default.asp?pID=134

If it were me Id put an AFR 180 head on, thats all it needs. However, you may want a little "more" (cam, bigger intake)down the road, so you may want to consider their new Eliminator 195 street head. At $1400, its the best bang for the buck Ive seen.

If it's just going to be a street only car, why bother with the expense of the 383 and 400 hp? You'll never be able to use the full potential of that motor on the street, especially those specs.


I have talked to everyone who will listen about replacing my numbers matching 350, and they all said the same thing, "might as well build a 383 for the extra torque, your car's kinda heavy, you'll love it". So I went with that idea since the beginning of the build. Now my rotating assembly is here and it's about time to assemble the short block. I know I need to get a cam in there first thing so I'm trying to make the cam and cylinder heads a good match for each other.
I'm hoping the 383 wasn't a mistake, I love to drive the car and I love it's current street mannors, never runs too hot, nice vacuum for power brakes, etc. Pretty much everything except the serious lack of power :boring:

No, its not a mistake. "If you build it, the tire smoke will come".

I have a 383 in my 70, currently running dart iron eagle heads with 2.02/1.60 valves, 200 runners and 64cc chambers, approx. 10.3:1 comp. The cam is not optimal, but it pulls nicely. I ran a best 2 weekends ago of 14.93 with 2.4x - 2.5x 60' times (terrible) and short shifting between 4 and 4.5K rpm. This is on a cam with under .50 lift, and it was shifting mid powerband! Granted 14.9 is not that impressive, but for it being my first time, terrible launches, and short shifting - there is a lot left.

I built a 383 4 years ago and it's been in a ~6000lb 4x4 (one ton diffs, 205 tranfer case, th400, 10" 3500 stall, 4:10's, 35's"). It's awesome, anyone who rides in this truck can't get over how well it goes. I ran 14.20@90mph last year and I'm not even hitting third gear at the top of the track!
My combo is:

10.2:1 compression

Vortec heads, stainless vavles(1.94/1.50), screw in studs, comp cams springs for .550 lift

Pro magnum rockers 1.5 ratio, (dyno'd with 1.6 roller tips but I got a good deal on the pro magnums and I've read vortec's don't flow past .500 lift so I swaped to the Pro's)

Comp cams extreme energy 12-243-3, 226/236@.050 , .480/.498 lift, 111 centerline(this cam has a nice idle, shakes the truck just enough to let you know it's there)

Edelbrock Performer RPM

Trans-adapt torque swirl spacer(worth 10ft/lbs, didn't move the horsepower which I thought was weird)

Dyno'd with a Holley 750 DP and I ran it with that carb for three years, just switched to a 750 vac. sec. Demon thinking the fuel mileage would increase and it didn't http://www.chevelles.com/forums/images/icons/icon9.gif.

I put little things in the motor like a windage tray, lifter valley baffle, crank shaft scrapper(all supposed to be worth power)

ARP head studs, main studs

CAT crank and H beam rods 4340 (I was very sceptical about CAT because at the time they were very new, but the price difference between them and SCAT was incredible and I could'nt afford to step up to Eagle or SCAT so I rolled the dice and so far I've been lucky)

This motor was put together on a budget and made 420hp@5400rpm and 500ft/lbs @4100rpm. This motor makes 400 ft/lbs at 2500rpm and is making 450ft/lbs at 3500!

I've just sold the 4x4 so I'll have the 383 in my 67 Chevelle by spring, I'm switching to Edelbrock E-tec 200's and a roller looking for 100hp and low 12's, high 11's on motor.

Build the 383, you'll love it.

I would go with AFR 195cc heads with 2.02 valves, a solid lifter cam around .525 lift and 240ish@.050. Top it off with an rpm manifold and you will have a strong running small block.