My 1984 351w is in a machine shop for Eng. balancing before a rebuild. The engine will go in an f1 (48). I have most parts including dished pistons and it is coupled to a c6 tran. Rear end will be a 9" (don't yet know the gear ratio. My desire is to have the f1 as a street rod with good mid range power (around 350 hp) But, I need some help selecting the AFTER MARKET HEADS first so they can be matched with proper camshaft and intake manifold (to b.e purchased)
At this point the best prices I have found on heads appears to be on EBAY. I need some help with head combustion chamber size. Suggestions about selecting the right heads for my requirements and combustion chamber size will be welcomed.

 

What size dish do the pistons have?
What will be the installed compression height?

The typical aftermarket head will have anywhere from a 58cc -64cc combustion chamber, all of which will work on your motor with the right piston. Static CR between 9 and 10:1 is fine for a street motor on pump gas. Once you know the answer to the above 2 questions and select a head gasket any one of the online compression ratio calculators will tell you what your final CR will be.

 

The racing head serivice (rhs) is the best value ihmo. If i was you i wouldn't get edelbrock performers or world products. Been working with a new pair of world products heads, and they suck. A afr 165 or trick flow twisted wedge 170 would be better.

 

thanks fordeverpower
conanski I have no idea how to find the"installed compression height"

 

I am going with the Trick Flow "Twisted Wedge" heads myself. Will be ordering them soon as my tax return comes in

 

Ask your machinist. You want to know if the top of the piston will be flush with the deck surface or down in the hole, and if it is down.. then how much.

There are a lot of very good heads on the market, some proven and some not so much. There is also a lot of flow data on the web, and while it's not all accurate it's probably close enough for comparison purposes. Here's a chart I found while researching heads for my 5.8 build.

 

pretty good chart, avenger and afr are cnc, powerheads ports stock heads and others. Canfields are very good but i think cost as much or more than the others.

I have used a set of gt40p from tristate cylinder head. They had 1.94/1.54 valves, and seemed ok. I think you want a little more than them though.

 

Edelbrock 1.90s are pretty good over stock,Trick Flows require special pistons

 

What do you mean trick flows need special pistons?

 

Edelbrock makes a ton of heads, some just a little better than stock and some right up there with AFR and such. Another company that isn't on the chart above is Dart, they make both cast iron and aluminum heads that compare very well with the best on that chart, and for considerably fewer $$ than the top names.

 

When I built my 351 the first time I had to fly cut the pistons for valve clearance.When I stroked it out I just put the TF pistons in it.

 

Wether you need them pistons are not depends on the cam you pick.

 

twisted wedge have the valves in different locations. a lot of the time this will cause piston to valve clearance issues.