[dragula81]

I have a bunch of heads that I'm about to sell but I want to keep the best set for myself for an upcoming 455 build in a 2nd gen TA. Below is a list of what I have right now. I need the accessory bolt holes.

I intend to build just a streetable, weekend racer on pump gas. I get machine work including port and polish work for free by a local builder so I figured that I'd just use a set of these heads since I already have them rather than going with aftermarket alum heads.

So, which ones out of the list below should I keep for me? I know that a lot of people run the 6X's but I wasn't sure if I might have something else on my list that would be a better choice.

Thanks for any help!

(Note that lines of the same color are matching sets)

[Ollie]

Any of the 6X-4 heads # 3, 7, and 12. They will have a 96 to 98cc combustion chamber. On a 455 these will have a pump gas friendly 9.0 to 9.5 cr. These will also have all the correct accessory bolt holes for a 2nd gen TA.

[BVR421]

IMO, They are all pretty equal in stock form or ported either one. Pick the head by combustion chamber size to get you 9-9.5 compression.
If you are going to run them stock or do some home porting, use yours.
If you are going to get a pro porting job done, ask the porter about useing their cores, it may be cheaper to sell all of yours and use their core when you figure shipping costs.
Also consider a used set of well ported factory heads from someone who is upgrading to aluminum race heads. Ive seen some real bargains in the classifieds, like nearly half price on for example 6X/260cfm heads that were originally 12-1300$ from respected porter.

[steve25]

Those #64 would be great if they have the larger 1.77" exh valve already you would be starting off with a better exh port than the 6X without porting, other wise it should be a ported 6X-4 head with out question fitted with the 1.77" exh valve.

[OINK 1]

1970 #15's: RA3 combustion chambers, 10to1, install screw in studs and drill and tap the end 2 exhaust flanges for headers. YA notice how they're not listed ???

BIG TIME ASS KICKERS.

Pontiac Gregg