xpndbl3

iTrader: (5)

I have a pair of 462 heads off an 69-79 350 motor. I was wondering if it is even worthwhile to port these heads and use them or are they paper weights??

thanks
steve

F-BIRD'88

These are exellent heads to port. They like bigger valves too.
The only drawback is they don't have any accessory bolt holes
on the ends of the heads.

They flow about 214 cfm stock. A simple general port job will
get you 225/230 cfm and 180+ ex cfm.

A full competition port job with big valves can be 260 cfm+
200+ exhaust.

These heads should be magnafluxed for cracks before
investing any $$$ into machining.

AJ_92RS

Camel Humps!!!!! :hail:

I had a pair on a 350 in a '72 Nova. Pocket ported with a Holley high rise intake, Holley 750 VS, Crane Fireball solid cam (302 dur/.510" lift), Muncie M21 4-spd, 3.36 gear, and a peg leg rear end gave me a 13.54 ET at 114 MPH on 14" (235/60/14) street radials.

I kinda had a traction problem.

I miss that car.

AJ_92RS

BTW...... I forgot to give you this link. I was too busy being sad about not having that car anymore.

http://www.prestage.com/carmath/DesktopDyno.asp

Go there. I don't know if those are stock or ported. Out of the three flow charts on there, none of them say.

xpndbl3

iTrader: (5)

well i can't tell if the heads say #462624 or #482824.

I looked and I can't find any info on the #482824, so i'm pretty sure it's the #462624 on the heads. But my problem is the heads to have accessory holes, so that's why I didn't think they were camel hump heads.

Any ideas? ALso, on my #416 305 heads the "6" is very easy to determine. Would it be the same font type on the other heads. If so then it's definately a "8" on those 350 heads, but i can't find any info on them though.


I'm lost

Steve

Riley's35089rs+

I think you have your # confused or you are looking in the wrong place.......look under the valve cover you will see the # here.....

RB83L69

624 heads are junk, among the worst ever. They are resopnsible for such engineering marvels as 170 HP 350s and 180 HP 400s.

Here's some double-hump heads with bolt holes.... casting # 3927186. You might want to check the block casting while you're at it... these parts didn't come from the factory as the same motor.

RB83L69

Here's the other end of one.

88 350 tpi formula

iTrader: (9)

are my 3973493 heads any good? they are the large 76cc head with 1.94, 1.50? valves they are the stock 400 heads. I would rather have a set of iron l98 heads but, every one wants way too much for them so I am thinking about those. I know my compresstion ratio will drop to 8.5:1 with those large 76cc chambers

xpndbl3

iTrader: (5)

well if it is the 624 heads then they should be junked then??

but the 824 heads are good?

Steve

the engine is a 69-79 350 that's all i get out of the casting number

89RsPower!

check the plate on the front of the block pass side head under where the alt would be underneath the head.. should give ya a lil more info

RB83L69

Don't know of any 824 castings, never heard of them.

Any 70s smogger heads you come up with are garbage. They're part of the package responsible for 170 HP 350s and 180 HP 400s. Garbage. You don't need to ask about every different casting number for the same junk, just throw it away and get someting decent.

Unless of course you want to build a 400 with 180 HP that gets about 12 mpg. Then they'd be just about perfect.

The stamping on the block will not tell you anything about the head castings. It may tell you a little about whatever sheet metal the block itself started out its life wrapped in, but that's about it. Still pretty useless any way you slice it. In all the years I have been doing this, I have yet to find the first scrap of value from that particular piece of info, with the exception of coming up with a "numbers matching" setup for car shows. In normal real-life engine building, I can't imagine what causes people to care what that number "decodes" to.

If you want to know what a "double-hump" or "camel hump" casting mark looks like, look at my pics. Those happen to be one of the double-hump castings with bolt holes. Don't bother with ones that don't have the bolt holes, they will not bolt into these cars properly; no brackets exist, no drilling & tapping is possible, etc.

There's a world of difference between 70s smogger heads and L98 heads. That's kind of like opposite ends of the spectrum. The one is in no way a substitute for the other. I'd put 416s on a motor before I'd use that 70s dung.

If you want an engine that produces real power, the first, foremost, most important, indispensible component you absolutely must have, is a set of good heads. All else is a waste without that. It won't matter what romantic brand of rods you use, or what custom forged pistons, or what cam, or what intake & carb, or anything else; if the heads are not good, the motor will not run good. Period. Watch the classifieds on this site for L98 heads, people are selling tehm all the time, for entirely reasonable prices sometimes even.

84TAProject

I can vouch for the crappiness of the 624 casting heads. I have a pair in my basment, and you can see the 1/4" of metal blocking the bottom left corner of the intake port. I remember I was going to put these on my 350 thinking my 487 castings sucked, but visuially nothing could be as bad as those 624's. The 487's at least had large ports on them, though they 76cc chambers. So I have low compression, but I use that as justification for a blower.
Why do I still have the 624's around? they get to be the test heads for porting. Oh and in a book I have (I dont know the name, I left it in my dorm) it states that 624 casting heads were used on 70-73 LT1's. There is no possible way those things could support the 360 horse 350 that was made then. There is a ton of misinformation going around regarding those old heads. Apparantly 487's came on the LT1's, but I found a set on my 71 truck motor. Did they put LT1's in the truck? I strongly doubt it. These guys here know their stuff, and you can pretty much take advice from guys like RB83L69 or F-bird88' as law when it comes to building small blocks.

RB83L69, I ordered a ZZ4 intake on your input. It should be coming in tommorow (except we're supposed to get 18" of snow tonite) and once the snow melts enough for me to get the car on the road, Ill let you know of the improvements over my holley Z series intake I currently have on the car now.

F-BIRD'88

GM does sell a head with the casting #462624
it is part#464045. This head is a far decent casting.
It is the replacement for the 441/487/336/ open chamber 76cc type hi perf head of the early 70's low compression Z28/LT1 motor. These do not have the scolloped out light weight casting.

Even thou it has the same casting number it is not to be confused with the low perf light weight casting piece of ****
your likely to find laying around on junk 180hp 350's

The good over the counter hi perf head comes from the factory machined for screwin studs, guide plates and 2.02x1.60 valves.
You won't run into this head that often.

The common low perf junk yard "624 head" has small 1.74 intake valves and real crappy ports with lots of core shift. They are known to crack. Junk

chymos

So how do the 426624 casting # heads rate compared to the more common "use these heads" casting numbers out there?

(I just found out that the used 350 I've been fighting to get running have them, and found this thread via search)

RB83L69

See above

Please have them melted down as soon as possible. Do your part to help erase the collective memory of this disgrace.

chymos

RB, take a closer look at F-bird'88's post:

----quote-----
GM does sell a head with the casting #462624
-----/quote----

----quote-----
Even thou it has the same casting number it is not to be confused with the low perf light weight casting piece of ****
your likely to find laying around on junk 180hp 350's
----/quote.....

it's the 462624's I'm asking about, not the junk 624's

edit: they came on a circa 1980 crate engine....not a junkyard engine....

RB83L69

Considering that there are a few hundred or pehaps as many as a couple of thousand of the one in existence, compared to millions and millions of the others, I'd have my doubts. The odds aren't in your favor.... they're on the order of thousands to one against you.

It's easy to tell if they're the "light" casting or not, from outside the motor, though. And of course, if yours have pull-out studs, that would pretty much prove beyond all doubt that you have the regular ones that all of us have loved to hate for all these years now since they appeared.

chymos

Ok....considering how little experience I have with this sort of in-depth stuff......got any pics illustrating what you're talking about?

RB83L69

Here's a set of real heads (double-humps with bolt holes) compared to "lightweight" heads. Notice how the lower set is scalloped, or "dimpled", between the outer head bolt holes, specifically visible between bolts 2 & 3; while the upper set is straight there.

RB83L69

Also, while you're notcing things, compare the exhaust ports of the 2 castings. Look especially at the "septum" between the 2 center ports; and on the end ports, look at teh distance between the bolt hole, and the port.

Which one of those is going to run better, and why?

The lower heads are 624s BTW.

chymos

in the bottom pic it's kind of hard to see the things you're talking about due to the position of the heads relative to the camera

I see the scalloping but it's hard to see much of anything specific about the exhaust ports. the camera's too directly pointed at the top of the head.

RB83L69

Yeah, it's pretty lame.... I got it off e-bay.... the upper one is one of my own motors. Still, it's easy enough to pick out those details. Especially the straight edge of the good castingvs. the wavy or dimpled or indented edge of the outer edge of the 624 casting.

I'll play with that image a little and see if I can enhance it any.

RB83L69

Try this

Still didn't work, let's try one more time

chymos

Hmm. The lower exhaust port showing on the 624s looks kind of deformed.......could be partially the lighting, though. Can't really see the "septum" on the center pair of exhaust ports.

If I have one of the sets of rare good 624s would they have the straight edge on the lower bolt holes like your heads?

edit: FWLIMBW, the other "numbers" cast into the head include "GM 3" (opposite end from casting #) "21" (next to "GM 3") and "E208" (next to casting #)

RB83L69

I would expect so but I'm not positive. They would also not have the pull-out studs like the ones in the pic.

That really is a lousy pic.... here's another, this is 882s I believe. Look at the size of the exhaust ports, and the shape of the intake ports. Although, that is stuff you can work on by porting; the things you can't fix are places where there's already too little metal, but you need to make the hole in it bigger. 882s and 624s (along with most of the other "light" castings) are thin around the exhaust ports, such that even if you don't hit water while porting them, they tend to crack from the heat in the thin metal.

chymos

So the studs are what the rocker arms attach to? What do the screw in type look like?

RB83L69

Like this...

chymos

Ahhh, I see. Nope, don't think I have the good ones.....but at least they'll get the car on the road

RB83L69

Well that's OK, crappy heads are a whole lot more common than good ones, and I've had an embarrassingly long time to pick up good ones without spending much $$$$; get it running, but don't expect too much out of it, and don't sink any money into those heads. Save up and get something decent.

chymos

How good are the L98 heads?

RB83L69

Decent. Good flow potential when ported too. They were the best flowing ones in stock condition as far as junk heads on cars since the double-humps, up until the Vortecs came out.

chymos

So would I be better off getting used L98 heads from thirdgenresource, or saving for the Pro Topline Vortecs?

Ray87Z

So are the 487s worthless as well (71-72 LT-1 head)? I've got a set sitting in my garage I was going to try to sell, may not be worth the damn trouble...

RB83L69

The 487 isn't too bad flowing, but has large chambers... you end up with low CR unless you use domed pistons, which will make ping at lower CR than flat-tops and small chambers... go ahead and sell them, get what you can, should be worth a couple of Bens, some people could make good use of them (blowers for example) and of course some old-timers that haven't adapted to the changes of the last 30 years

1970 chev truck

I

1970 chev truck

I am working on a 1970 Chev custom 10 pickup, I have a 350 out of a lat 70's to early 80's Z 28 Camaro. I have the heads pulled off of it and the casting # is 462624, I was wonderin if any1 know if those are decent heads to work with or if they are just crappy smoggers. I also have a set of heads off of a GM Targetmaster-Hecho en Mexico, they are equivalent to 993 heads, any1 that has info on these heads, please post a reply.

Thanx,
Paul

sofakingdom

iTrader: (1)

I think if you read through this post, you'll see a fair bit of talk about 624 heads. Looks like RB isn't too fond of them. Ya think??

Personally I'd put the 993 casting in the same class with 624.... smogger turds. Basically they devalued some perfectly good cast iron by turning it into those.

SpitotRs305

i have the 993s on the same crate motor they are a waste of time even throwing them out but i was considering running them anyways with forced induction

five7kid

iTrader: (14)

Now how can you tell????

Please, people, if you search (and thank you for doing that), at least read the thread before you post the very same question that was originally posed.

1970 chev truck

Ok, well i guess it was kind of stupid to post that when there was a bunch of stuff about them. I am 16 years old, but believe it or not I actually know what I am dealing wit and talkin about, so on wit my next question, as i stated b4 i am working on a 70 chev pickup. I would like to get the most out of the engine that I am rebuilding with the parts that I have available. The engine that I bought has a new cam, flat top pistons and a holley 500 carb. But as every1 knows u got nuthin wit out good heads, and I dont have any good heads. Ne1 have ne suggestions on affordable heads for this engine, I am associated with the WISSOTA racing world so I should be able to get my hands on sum pretty decent stuff. Any replies are greatly appreciated.

Thanx,
Paul

7.0 camaro

i think every factory head is junk. get some afr's or dart or something. however if you find some 461X or 462X. keep them. they were gm drag racing heads. they are pretty good.

Air_Adam

They weren't "drag race" heads... they were production line heads, just like the others, they were just prepped for high performance - 2.02/1.60 valves, screw-in studs and guide plates. Thats the only difference from standard 461/462 heads. Some of the over-the-counter ones had angled plugs too, but I'm not sure if that was for those castings.

1970 chev truck

I have a set of what i believe are 441 or 441 X or something like that, would those be a decent head to put on a daily driver 350?

Thanx,
Paul

sofakingdom

iTrader: (1)

Not really...

They flow OK, but the chambers are 76cc. HUGE. Meaning, low compression on a 350.

Using large-chamber heads and dome pistons is a recipe for a disappointment, with modern fuel. The way to make power these days, is with a small-chamber head and a "reverse dome" piston, which in effect puts the chamber half in the head and half in the piston.

Those heads are more suited to a larger motor (400 +).

Stick with heads of 64cc and less. Trade those to somebody that can use them, they're not worthless or anything like the 624 or 882 or 993, they're just not the right thing for what you want. Turn them into something else that you can use.

1970 chev truck

Ok, I have yet another question about cylinder heads. I have acquired a set of 3973487 heads, information on these, the only thing that I know about these is that they have 1.94 intake. I also have a set of 3951598 heads, I cant remember for sure the # but pretty sure the last 3 digits are 598. Which would better suit a daily driver 350?

Thanxs,
Paul

89Nighthawk

Sounds like a nice car, but camel hump heads aren't very good heads. They were in their day, but they aren't anymore, they are going on 40 years old. You can get much better heads now.

1970 Chevy Truck
As for your latest head question, I'm not familiar with either of those head castings so I can't help.

1970 chev truck

Thanxs anyway, i have found sum info on them and they sound like pretty good heads for what i am lookin for.


Thanxs,
Paul

7.0 camaro

i bought my heads used for $600.00. they are dart iron eagles. 230cc intake runners 2.08 1.60 valves. 1.55 dual springs. 250lbs at the seat and 600lbs open. irun a solid roller cam with about 630 lift. your gonna spend 3 or 400 on a set of heads go ahead and find some that are worth it. the only stock heads that are ok is the vortecs.

djritter

I am so upset after reading this. I cracked my 882 heads in my SBC 350 and I am about to pay a mechanic close to 1400 dollars to put new heads and a 120$ elgin cam in (I bought the cam). I looked up the casting number when I found out what it was (took a picture at his shop) and they are the 463624. They are from a machine shop and have just been refurbished I guess, is there any hope or did I make a really bad decision. I know this was discussed on here a lot but I don't know hardly anything about this, I can't even tell from the pics if these are the "good" ones, although I assume they aren't. I paid 400 for the heads from him, the rest was the labor. feeling uncomfortable about now.

http://postimg.org/image/j163frdph/

http://s2.postimg.org/jt8reyhwp/heads_3.jpg

http://s2.postimg.org/6qi6ssy09/heads_4.jpg

http://s2.postimg.org/uhcidsrvt/valves.jpg