i have a 400 destroked to a 377 and i was wondering what the best way is to make the most power without nitrous turbo or supercharger. i also wanna run on pump gas and i have a range of carbs and intakes that i can use because my grandpa has a bunch from 600cfm to 1000cfm. i should be getting 202 heads but i dont know anything about them. thanks Ty.

You will need decent heads, aluminum. You will need a solid roller cam and 11 to 1 compression. Have any of that?

good heads and cam.

hope your lookin to turn sum rpms. thats the reason 4 most 377.

Decent heads,yes.No reason why he HAS to have aluminum.
His choice of camshaft should be well thought out,and matched to his cylinder heads.However,while a roller is superior,there is no reason why he HAS to have that,either.There are plenty of good flat tappet choices out there.

the heads that i would get would most likely be cast iron and im gunna have to buy the cam

Doesnt have to be, but unless you want to spend hours on grinding away at those iron heads, it wont outrun a good set of aluminum from Dart/Brodix/AFR/Canfield/etc. Not to mention 50lbweight loss.

Doesnt have to be a roller either but they are much better cams than flat tappets.

377 is a good base for some rpms... give it 11 to 1 compression or close to it with aluminum heads/single plane, 750-800 cfm carb, and a decent roller cam to match and it will fly.

If you do stick with whatever iron heads you have, keep compression down and the cam will have to match the heads as they probly will be limited in performance unless heavily reworked.

I dont think the best way to make most power as you can without going power adder means iron head and flat tappet...but some guys have gone really fast with solid flat tappets. But they usually have good heads

So being iron makes them flow worse?Wrong answer.Dart and World Products make iron heads that are 220cc+.

If I wanted to build a ballsy but streetable 377 on a reasonable budget, this is what I would use:

- Holley 300-36 intake (out of production now, but still not hard to find and not expensive)
- Holley 4779 750cfm double pumper or 3310 750 vac secondary
- reproduction LT1/L88 14x3 air cleaner (only way to get that intake to fit under a stock hood and still breathe)
- Hyd roller cam in the 236*/242* @ .050 range
- Cylinder heads with 195-210cc intake ports - World and Dart both make very reasonably priced iron heads in this size
- Keep CR to around 10 - 10.5:1
- Hooker 2210 headers (1-3/4" longtubes) or similar
- full 3" exhaust system of your preference

And they still dont compete with other 220+ cc aluminums..... I did not say Iron heads flow worse than aluminum just because of the material itself.... but 90% of the iron ones you can buy now dont flow like the cnc ported aluminum heads out there for the money. Its easier to develop and manufacture an aluminum port, and todays technology has produced great ports. Days of racing iron heads is over.

Oh and cc's dont mean flow numbers nor does it mean performance. Lot more to the head than just overall volume of the runner.

From what the original poster has posted, it sounds as if the heads he was trying to use are some old factory castings that are no better for racing than they are for paperweights. Motowns may be worthy but arent any cheaper than most aluminum heads. Why spend same to put 50lbs weight on the car?

Thanks for straightening me out,pal.I never knew how wrong I've been doing things all these years.

Just saying man its my opinion, if you have done well with iron castings have fun. I dont know anyone running fast around here with iron heads unless its heavily worked over. I'll take the 50lb weight savings for 200 extra bucks anyday