ive searched thru the boards, and thers only 1 or 2 threads on 383's, but none talk about NOx.

so my question is, what specs should i be looking for when selecting heads? obivously ali heads, but what chamber size, what SCR should i have, what kind of flow numbers should i be lookin at (int and ext), and how do these numbers change if i want to put a 150 shot NOx as a "once in a blue moon".

my setup isnt complete yet, i want to know as much as i can before i make decisions, all ive really decided on is the crankshaft and the rods. i will have a ported TPIS big mouth intake and runners, and a 58mm TB.

Tony

 

ttt, some input plz.

 

well, what kind of money are you looking to spend?
trick flow's got a 195cc head that would work great or some AFRs.

 

Heres what id look into for heads:

72cc Chambers which will put you at about 9.8:1 Compression ratio
195 - 210cc intake runners, because a 383 flows a rather large amount of air, the larger ports will allow more air flow at a higher RPM.

If you plan on using nitrous, gap the rings, and get at the mininum Hypereutectic pistons, some I beam Rods, and if possible a forged crank.

Chances are you will want to eventually want to run more nitrous, so you can plan ahead and put some studs in to hold the heads down, or atleast ARP head bolts.

Some good options are:
AFR 195/210cc Eliminators
Brodix 200cc
Dart 200cc

 

i was looking at the brodix, they have some awesome build-ups, and money isnt a problem either.

ive decided on a scat 9000 lighweight crank, will that be able to take the nitrous? and since ill be on the bottle maybe once or twice a season, will the bigger ring gap hurt off-bottle performance or reliablity?

PS: thanks sheldon

 

If you are only going to run the bottle 1 or 2 times a year, then just build the motor as if you were running n/a. You won't know the difference and it's not worth it to buy components designed for high hp juice use if you are only shooting it 2 times a year.

You are still rpm limited by your intake on a 383. Get the trick flow 195cc heads from summit or jegs, a scat or eagle cast steel crank kit(don't need lightweight), shoot for at least 10:1 compression, port and siamese the crap out of the base/runners/plenum, and shoot for at least 8:1 dynamic with your cam(depending on gas used).

You need to put your money where it will work the best. If you are using a stock 700r4, then it might give up the ghost, so the money spent on a lightweight crank/rods/piston combo could have been spent there instead.