Dragula

I need y'alls help. I finally have the money to finish my 383ci that I am building. It is time to order heads. I need y'alls input on which ones to get. Here are the choices.
1) Edelbrock Performer RPM Aluminum
2) TrickFlow 23 degree Aluminum
3) AFR 180 or 190
I know the AFR heads are by far superior. The only problem with those is the 68cc combustion chambers will drop my CR to 9.2:1. The Edelbrocks and TrickFlows will keep it up around 9.6:1. I know that with aluminum heads you need to keep the CR up due to heat more being transferred out of the cylinder to the heads. Will the increased airflow of the AFR's make up for what I am losing in CR. Will 9.2:1 be too low to use with aluminum heads? Any other suggestions out there?

383ci
forged crank
forged 6" h-beam rods
Kieth Black 164 Hypereutectic pistons with +19cc dish
Edelbrock RPM Air-Gap Manifold
Edelbrock RPM cam
fully machined 4-bolt block (.010" decked...how much will this
increase CR?)

Chuck Everly

All of them are good. The AFRs can be shaved to get the CR you want. I built a 383 a few years ago and used the Edelbrock heads. I had no complaints, they are nice quality heads. Their flow numbers are not as high as the others but then they are a velocity head.

If you have the cash get the AFR heads. If it were between the Trick flow and Edlebrock I would pick the Edelbrock. The only real reason is I know they work with your combination. With your combination the motor should make around 410 to 420 hp and 430 to 440 ft/lbs of torque with a good carb and free flowing exhaust.

I hope you have a manual transmission or a loose converter, that RPM cam has a lot of duration and it is pretty lumpy at an idle.

One last point, why hypereutectic pistons? You went with a forged crank and rods and put in cast pistons. I made that mistake and wish I had used forged pistons. I was afraid to spray the motor with the hypereutectic pistons. They are better than cast but are still prone to crack under extreme duress.

Dragula

The engine will never see anything other than a normally aspirated system...no NOS or supercharging. I had a hard time finding forged 383ci pistons for use with a 6" rod that kept the CR where I wanted it. The ones I did find were more than I had the money to spend at the time. Since it has all been internally balanced I guess its a little too late now.

onebad82z

iTrader: (7)

If you have the money definitely go with the AFR.AFR can mill these heads to your specs to keep your CR where you want it also,they did it for me for and extra $50.

Dragula

Won't milling the heads effect the alignment of the intake manifold? If so do you just use a thicker intake gasket? How much can you safely mill the head?

1bad91Z

iTrader: (1)

Do yourself a favor and get the GM aluminum fast-burn heads! They also have a 62cc combustion chamber that would bump up your compression to ~9.8 to 1 with the parts you selected. Read my topic that I posted in this forum called GM Fast-burn heads. This should give you some good info. Hope this helps.

onebad82z

iTrader: (7)

If you get the AFR heads they will mill the intake side to fix what was thrown off when the heads were milled,it is just a given that this is done and corrected when the heads are milled.I didn't run any special gaskets on my intake,just ones that fit my port size and all was well.

SUPER CHEVY66

iTrader: (1)

brodix makes a set of nice aluminum 23 degree heads that flow pretty well so take a look at them.

iroc22

If you're gonna go with Trick Flow, go with the G2 head. The AFR's make superior horsepower, but for quality the Edelbrock's cant be beat.

AJ_92RS

By using the comp. ratio of 9.2, you can go to SMOKEmUp.com and use their comp. ratio calc. and calculate it by using a Fel Pro embossed shim gasket of .015" comp. thickness.

That will increase the comp ratio to about 9.73-9.75:1. You can get the gaskets from Summit for ~$20.

If you call Summit and ask them, they will tell you which intake gaskets you might need to make up any difference in the shorter compressed height of these gaskets.

Good luck,
AJ

espirocz

iTrader: (2)

G.M. also makes an aluminum L98 Corvette head with a 58cc combustion chamber and ZZ4 valve springs. FYI. Double check with GMPP dealer on runner size though, might be too small.