I've been planning on building my 430 up using a set of TA Stage 1 aluminum heads but based on new budget constraints i'm seriously looking into porting the heads I have, and using a bigger set of valves from TA. I've got a cam and headers and am still able to afford a new manifold, but the heads are a kick in the knickers. has anybody done it? I'm not afraid to start hacking away at these things, just gotta make sure I take it slow right? i've seen videos and read articles about it but i was just hoping for some advice before i get to it, as i've heard of a lot of people messing their heads up. also, anybody know how much of the job i would have to have done by a machine shop?
If you've never ported heads before and don't plan on doing it much in the future I would send it to a known Buick builder. Gessler, PAE, Tri-Shield etc... $500-$800 in porting will get you some serious performance.
I haven't done Buicks but have done 460 Fords, Chevys, Toyotas and Pontiacs. More than that, its the theory, that seems to matter. Straighter is Better. Not too smooth on Intake walls. As smooth as possible on exhaust and combustion chambers Reduce valve guide bosses as much as you can without compromising strength or length Enlarge and transition pockets from point of valve grind. Port match all mating surfaces. Keep in mind that amost every surface you are grinding has water on the other side, so don't overdo it. There are alot of folks here running iron heads with impressive time slips. I got great gains out of my motors using these common sense principles and suspect many others have, too. If you send to a jobber he will have to weld and reshape ports affected by heat crossover. I'm not sure you'd come out much better, dollar wise, than you would with the new TAs.
I'm currently talking myself into porting my '68 430 heads for use on my 455 block. The 430 heads have better compression than '71-'76 455 heads but the 430 bore diameter is just small enough to make using the stage 1 valves useless. There isn't enough room for the incoming air/fuel mixture to go around the valves into the chamber without smacking the cylinder walls. This is why the 69 400 stg 1 had the exact same head as a 69 Electra. If I take my heads to a shop and have them ported it will cost almost as much as a brand new set of aluminum heads that will not only outflow what I could do myself, but there is the advantage that aluminum allows higher compression per octane of gas, and of coarse it would lighten the front end up more than 50lbs. A Buick big block with alum. heads weighs less than a small block chevy with iron heads! Then again porting the heads myself would be almost free. Just gasket matching the ports of your heads and intake should make a big difference that a novice should be able to perform without screwing up too much. There are articles on the internet on porting Buick heads at home the right way but I have been reading so many web sites lately I can't remember where. I guess that's kind of a good thing, when I first got interested in Buicks in the late 70's and early 80's everyone told me Buick engines were only good as boat anchors, after which time my '69 430-4 Electra usually would beat their 440 RoadRunner or 350 Corvette or 302 Mustang or whatever.
Oh yeah, TA performance has what, 6 or 7 different big block heads in aluminum now? Awesome!!! Now that our cars are finally getting some respect everyone is getting in on it now. There are aluminum heads now available from a company called "bulldog" and even Edelbrock has anounced they are releasing Buick big block heads in their performer line!!!!!
1) Be sure to check them for cracking over the water passages, they are famous for that, most can be fixed inexpensively. 2) Unless your well tooled and extremely proficient with a die grinder you going to be stunned at just how badly your able to screw them up. (voice of bad experience) 3)I'm well read on many subjects, most of which I suck at in real life. Without the ability to match cc chambers and compare flow characteristics your just shooting in the dark. If all you want is a good port match you'll be surprised at how reasonable a pro will do that for you.
Thanks for the tip, I will have to shop around cuz the quotes I got on head porting are more than I paid for the whole car. Maybe they just don't want to mess with heads they are unfamiliar with and just quote an insane price to make me go away so they can get back to their belly button small block chevy stuff.
For what you guys are doing, I would suggest a simple Street-strip port with some combustion chamber work. If you have the big port version of this head.. casting numbers (last three) 963,965 and one other number that escapes the top of my head at the moment, they are 5% bigger than the later 455 heads to begin with. Cracking on the surface under the valve cover, between the spring pads is an issue with that casting, but most can be saved. Even with the stock valves, they will go in the 250/190 cfm range, or maybe a touch more. A $700 deal.. (not including shipping, which is typcially $40 a head, X 2, and then here and back).. so you can wrap $160 up right there.. Don't bother with the big valves, since your right, on a 430 bore you can't unshroud the valves enough to make good use of them, and doing a STG conversion and a full port on any iron head, in light of the offerings out there for Aluminum stuff now, just makes no financial sense anymore. And a STG valve conversion, without a full port, does little more than let you tell your buddys it has STG 1 valves in it.. simple conversions typically flow around 225-230 cfm, even with a competition valve job.
I did mine I put a set of 72' 455 heads on my 69 430 after i shaved them a little and then did some bowl blending. I noticed a real performance gain in the higher RPM's. It took me probably like three weekends in a row to finish. I did practice on my cracked 430 heads. I read an article from standard abrassives. But I didnt use their kit I bought the stones from harbor freight. and a nice quality die grinder. I think It was a good performance gain considering It cost me very little and it was my first time. will
And here is a set of 70 786 Stage 1 heads with extensive porting. I do not know the flow #'s or cost, but it looks expensive. And looks like a lot of work. These heads came on my 69 Stage 1. Michael.
Hey John.. We ran STG heads on a 430 race motor we had for years.. and never gave it a second thought.. while not as ideal as having the bigger bore, it won't kill anything either.. What I said was in reference to folks starting with iron heads, and considering putting stage valves in.. but since you already have them.. run em.. If you zero deck the motor which you should, then there will not be enough material at the top of the block to make a big enough relief, to really help anything out, in my opinon.. a bigger bore would help, but make sure you sonic check the block before you go with a bigger bore, and make sure there are rings available.. I do believe I have heard of guys boring 430's out to the 4.312 stock 455 bore, but I have never personally been involved with such a project.. so you want to make sure you sonic check the block, and consult with your builder before going that route. JW
For a step-by-step guid for porting Buick heads, go here: http://mywebpages.comcast.net/jholthenrichs/head.htm#Head Porting
hey thanks fellas. sounds like i have even more things to mull over about this than i thought. incidentally, anybody know anybody in the Seattle area with experience with Buicks who I could take my heads to? Also, does anybody know how well welding in these heads will hold up, because of the heat? I've welded cast iron before but it's not always guaranteed to hold up well to extreme temps... Just in case I go a little buck-nutty if I do them myself...
