Got a chance to pick up some 1969 #46 heads for fairly cheap. Guy is asking $300 for them. They will need a trip to the machinist but have no issues other than sitting on a shelf for 20 years. I have #11 heads on now. In the future not looking for major changes. Ill eventually switch intake and add 4bbl. Long branch and duel exhaust.
Are the #46 heads worth even messing with? They are small valve but higher compression.
IMO #46 head cores are not worth $300. They'll need a lot of work to make performance heads out of 'em.
According to the online info I can find, they came mostly on '69 400 2-barrel engines, and have small valves & press-in studs. They also do not have hardened valve seats. So, about all they have going for 'em is small chambers, in case you need more compression.
But, it they have screw-in studs. that will increase their value. I assume it cost around $200 or so to have Pontiac heads converted from press-in to screw-in. Can also add seats & 2.11/1.77 SS valves. But, all that costs $$$. If you give $300 for the cores, then have everything done correctly, you could easily end up with well over $1000 in 'em.
If I was gonna put that much into some early heads, I'd go with #12, #13, #16, #48, #62, or #64. That way, you could always sell 'em to somebody doing a '68-'70 resto. Don't think there are many '69 400 2-barrel restos going on.
They would go on a 350 and before anybody starts on the 350 build conversation, which I totally understand, this is a numbers matching "nearly" all original 350 car. I'm more than happy with the performance I will get after the few mods mentioned above.
I looked at the Wallace info and it lists the #46 heads at 10:1 compression on the 400. My #11 are advertised at 8.6 on the 350. I'm not sure how to work out all those apples and oranges between 350 and 400 but that does look like moving in the right direction? Of course as correctly stated the cost might not be worth it. I have heard that for a 350 the small valve heads are better? If you're gonna have small valve heads why not have the "better" small valve heads? My guess is I can get the 46 head s for $200.
In short my concern is at the end of the day, and my wallet, the gain is negligible.
"...this is a numbers matching "nearly" all original 350 car..."
So, I'm wondering exactly which parts are "numbers matching".
Is it the original block that came in the car, or just the correct casting number & block code ?
Since this is the 1st gen site, I assume the car is a 1st gen. I think the heads used on 1st gen 350's were the #17 & #47 on the 2-barrel engines. And the #18 & #48, on the 350HO engines.
Well I believe he said the head were going on a 350.
"...Don't think there are many '69 400 2-barrel restos going on."
I was referring to the possibility of selling the #46 heads, at sometimes in the future, should he ever wanna do so. Those heads came on several 2-barrel 400's. Also came on one Bonnie 4-barrel 400 and some 4-barrel 428's, according the info on the Wallace site. Just assuming that there are not many numbers matching resto builds, requiring the '69 #46 heads.
But there are lots of possible buyers for the popular big valve heads I listed. Those heads came on lots of Birds, Goats, & GP's. And they are used on lots of performance engines, in cars that did not come with 'em. Just a much larger market for those popular high compression big valve screw-in stud heads.
The 350 engine and drive train on the car are all original to the car. It still has the original 2bbl carb and intake. With the heads possibly being an exception. The car is a late 69 350. The current #11 heads are date code late 69. I don't know if the heads are original or not... I think the heads may have been swapped for a set already set up for pump gas during a very basic rebuild in the mid 90s but I have been told it is possible that some late 69s may have worn 11s from the factory. I have very good knowledge of this car since I am the second owner, the first being my father in law. However he has passed away and with him went some of the details. I did ask him once about gas and hardened valves and he said that was taken care of. At the time the importance of how was not important to me.
If I am reading the head numbers correct, and of course the chambers measure to match... the 46 heads appear to be a decent bump in compression without moving to big valve heads. If that is in fact correct they would seem to be great on a 350 build looking for 300-325 hp. They should... all else being equal... offer a bump over the other small valve 350 players 17, 47, 11. What I still don't know is what bump? Getting big valve heads on the 350 might not be the right move either. And chances are any of those will need the same work as the old 46s?
"...It still has the original 2bbl carb and intake...looking for 300-325 hp..."
I'm assuming you are not going to shoot for that much HP, using the 2-barrel carb. ???
"...Getting big valve heads on the 350 might not be the right move either. And chances are any of those will need the same work as the old 46s?..."
Can make 300 + hp, with small valves. But, those big valve heads already have screw-in studs. I assume that will save you $200, depending on machine shop price for converting from press-in to screw-in.
If you don't have screw-in studs, you may not be able to use enuff cam to make 325 hp.
The factory '68 350HO, with the #18 heads and an 067 cam was factory rated at 320 hp. Some online sources say the #18 heads had 64cc chambers. But if you get the CR up too high you may have detonation problems, with pump gas.
Some of the '69 350HO engines had an 068 cam. So, you may be able to get by with an 068, with press-in studs. The '69 had #48 big valve heads, with screw-in studs. But the 068 cam was used in a few press-in stud engines.
Now, if you have screw-in studs, it's no problem running enuff cam to make your hp goal. There are lot's of shelf cams that will do it, and still be very streetable. Some guys have got by with a decent cam, without pulling a stud. Some weren't so lucky. You may or may not get by with a Crower 60240 or a Lunati 10510312.
I agree with oldskool on the different heads, the screw in studs are the only safe way to run much more cam. I do favor Pontiac's big valve heads but they can give you a clearance problem with top of the cylinders on a 350. For this reason an HO 350 with #48 big valve heads had the notches cut into the top of the cyl for clearance. Like he said you can get decent Hp out of your engine, just keep crunching the numbers. Wich heads are available, verses your machine shop bill. Adding screw in studs to the #46s might be a good choice. Best of luck!
Thanks for all the advise. I finally got a first hand look at the 46 heads that were for sale. Basically good cores. Would need everything. And the guy seemed to thing they were worth every penny of $300 because of some ebay price comparisons. Short story is I passed on them. For now...
BUT this did inspire me to do a bunch of research and there are a lot of folks building essentially the 350 HO using the higher compression small valve heads, bore .03 over, moderate cam, headers or long branch ex manis and going to 4bbl. Yes in nearly all cases this does require a machine shop expense but reported results are very very good. This is the recipe I was theorizing without really understanding all the parts fully. Those higher compression heads were on 400s and were not so special but on the 350s they do very nice work. The alternative is just to run the standard family of 350 heads but since you are probably making a trip to the machine shop anyway.... why not.
Why doesn't everyone do this? Well... it cost some $$ and in the end you have a 350. That just makes no sense to many folks. But for those of us married to a 350 for various reasons, who aren't building race cars and who are very happy with 325ish hp, it sounds like the perfect solution. My car goes pretty well right now with a tired old bone stock 350 I can only imagine that an additional 75hp would feel pretty sweet! This combo should be quite happy on 93 octane gas and in my opinion if gas prices are an issue you got the wrong hobby! And I wish I drove my car as much as you do.
So I'm saving a few pennys and keeping an eye out...
The ONLY way to know what size chambers any head has is to actually measure the chambers.
I looked at some head info sites. looks like there are several other choices for high compression heads. Lots of guys have used the #17 & #47 heads. Looks like the '68 #15 heads are small valve, small chamber, press-in stud heads, as are '70 #16 heads.
According to the info, the #215 & #216 heads are small chamber, big valve, screw-in stud heads. I have #215 heads on one of my 455 bracket engines. Big valves will require the double cylinder chamfers. I've read that many of the earlier 350 blocks had the chamfers, even if they came with small valve heads. Can't comfirm, one way or the other.
Don't know you budget, but for around $500, you can buy some forged AutoTec custom pistons for a 350. These are much lighter and stronger than cast pistons, You can also get 'em with narrow rings, and you can get the pin hole placed where you need it, in order to get near zero deck height, without having to cut any off the decks. The pin height alone will pay for part of the extra cost of the pistons.
For $400, you can buy RPM brand H-beam rods,which are much lighter than cast rods. The lighter, stronger rods/pistons will increase the power of your 350.