I have a chance to get a set of 3998993 that are on a stock engine from a 69 Camaro. I ran the numbers on here and online thru some other sites and am getting mixed info. There seems to be 2 models of the heads, some had some 1.94/1.5 valves and seem to be smogger heads, and some were put on "low-performance cars and trucks"

My question is since it is out of a Camaro are the worth a damn?? And I can't find valve size info on the style of heads off a "low-performance" engine. The heads are still currently bolted to the engine hence why I dont know the current valve size.

So any help on figuring out what these heads are worth if they really are the better model is appreciated.

 

Those are NOT the stock heads off of a 69 Camaro. They may be "on a stock engine"... at the moment, but that doesn't tell you WHO PUT THEM THERE.

That casting first appeared in the early 70s. It is a typical large-chamber, low-compression, poor-flowing, smogger turd.

The stock valve sizes in virtually all 350 heads are 1.94" and 1.5". Even in "smoggers" and "low-performance" models. There's nothing special about those sizes.

You can be assured they are not "the better model". They're 993s. There is no "better model". Even between those 2 descriptions, "smogger" and "low-performace", I'm not sure which one would be considered "better". Or even, which one would be "worse". Both of those mean "melt them down for scrap metal" to me.

This is a great example of somebody making up a romantic-sounding story of origin for something, to dress up some kind of excrement with a catchy tale and make an inexperienced buyer think it's perfume. Kind of like "out of a Vette".... yeah they really were, out of the floorboard of one that he drove to the swap meet on the last day and picked up some trash for free that a seller hadn't sold and wasn't worth hauling back home. Don't spend your hard-earned cash on a fancy story.

 

Thats what I was thinking, my buddy has the engine and was willing to give them to me for free.....so I wasn't loosing any money into them.

Now for another question. I have a set of the 434 heads that were mildly port and polished, have 2.02/1.60 valves, screw in studs and guide plates.......are they worth doing anymore work to or will they never flow any good numbers. I got them in a trade for some junk interior parts that weren't for a Camaro anyway so I didn't loose out here either.

 

Also how about the 3782461X head? Found some decent ones and did some research and they seem to be some good heads for the price.

 

Those were good heads, in their day. They were the earliest of the "double-hump" heads, on 283s. Like all that early 60s cast iron, long since obsolete. We've learned a couple of things about how to do stuff better in the 45 years since those were cast.

They don't have the accessory bolt holes in them, so you can't mount your accessories to them.

Certainly not worth spending money to get, and then spending even more to overcome their physical limitations. You can do FAR better for less money and trouble.

 

For accessories it doesn't matter, I am lower mounting the alternator and have an electric water pump so there isnt anything else I need to spin. As for better technologies what should I be going to look for? I am on a limited budget for the time being until I get money there isn't much in the aftermarket industry that I can afford.......and I am not sure what years the Vortec stuff kicked in on the trucks and such so I don't know what to look for at the junk yard.

 

We're all "on a budget". That's about meaningless.

Vortec heads come on 96-99 or 01 trucks. Casting #s are 906 or 062.

The way to buy them is to tell the boneyard guy you need heads for a 97 pickup or words to that effect. DO NOT utter the word "Vortec", and DO NOT mention the casting #s. Just look at what they hand you, and if they're not 906 or 062, hand them back and tell them they're not the right thing so you're not sure if they'll work.

What you DO NOT want to do, is to let on that you have a clue that those are "hot-rod" parts. You want them to think that you're a roofer or something, and your work truck is down, and you need to fix it.

 

Good post, but you have an amusing way with words that made me laugh. I'll keep that in mind.

 

Good info there, definately will have to look into the local boneyards when I get a day off here.....one more ? on the vortecs.....which one of the casting # is the better of the 2?? I have heard the 062 are better, but is there really a difference??

 

"Now for another question. I have a set of the 434 heads that were mildly port and polished, have 2.02/1.60 valves, screw in studs and guide plates.......are they worth doing anymore work to or will they never flow any good numbers.?"

What would you call good numbers? does 230+cfm intake and 180cfm exhaust fall into the good numbers catagory?
Thats what i get out of my "416" 305 heads.
the 434's are simular enough that you should be able to get simular flow results with full porting.
Thats enough flow to make a little over 400hp with a big cam 10:1 cr etc.
The question is are you willing to tear them down and get serious with the porting.

You heads have a few things going fo them. They already have big valves, screwin studs etc and you already own them. If 400hp is enough you should be able to do it with those heads. If its not enough, get better heads.

Post some picks of the ports and chambers if ya can.

What heads were you using that got you a 107MPH trap speed?

 

I was using the 434 heads on the car to trap the 107 in the 1/4. Thats why I want to do some more to the heads, they seem to work well as is. As for flow numbers I don't know what it flows, but I am looking to make roughly 400 hp and then add on spray to make around 600 hp, and hoping for mid low 10s after spray. The heads always flowed well, I would float the valves before I would run out of air in the engine, so I know they were keeping up with my mild setup.

As for porting, I am tempted to do it myself, but I know a guy who has been doing machine work for 20+ years and he ports heads, but I was looking into the Standard Abrasives kit for porting and just do it myself. I am just looking for better numbers, I am not trying to be too cheap, but I am looking to use what I have to its best ability before giving up on it and throwing it away.....plus low 10s on 434 heads might raise some eye brows amongst the nay-sayers on here
----------
As for pics, I am going to pull the heads off the engine once I do the bearings, just to clean them up and check for any problems, so once they are off I will get some pics up here.

 

How much does the car weight? Your making good power with the heads as they are now. @107mph a 3500lb car (w/driver) needs about 400BHP. a 3000lb car needs about 340hp.

 

The car is almost stock except for the carpet and rear seats removed, fiberglass cowl hood, manual steering, manual brakes, no front sway bar, and thats about it for things taken out of it. So I am guessing with me in it, it is somewhere around 3300-3400.

I just need a bigger stall in the car because it has no launch out of the gate, thats why I have the MPH but no good times, but it was consistant, so I know it wasn't engine problems.

The new car will be the same as above except it will have a roll cage in it and eventually a forged small block and spray, I just wanted to keep my costs down on building it by re-using the heads and doing some work to them myself.