Brandon Crawfor

so im pulling my heads because of a blown gasket, and i noticed the id stamp (or whatever it may be called) and the last three numbers are 624
now ive heard to stay away from that particular casting because they crazk like mad...
i havent gotten them all the way off yet, but provided they arent cracked should i reuse them or try to fin some other heads?

sofakingdom

iTrader: (1)

At the bottom of the charts...

Look for something else.

Brandon Crawfor

any recommendations? somethin cheap cuz a seventeen year old working at mcdonalds does NOT have alot of money...

sofakingdom

iTrader: (1)

What are they going on? (CID, compression, pistons, cam)

shaggy56

624 heads would be great to practice porting on.

Sonix

iTrader: (1)

how long before you need to get them back on and running?

Assuming it's the typical "rip the motor out of grandpa's '76 half ton and throw it in the camaro", then it's a lame-o smog dog 350. If you can find some 416/601 heads off a camaro, port them up like mad, and put them on. You'll probably be out $100 at the end of the day (plus the gaskets and whatnot), and get higher compression and better flow. Cam it and you're set

Brandon Crawfor

its a 350, stock pistons and cam, and i need it up and running as soon as possible.
its my daily driver, i dont have another car to drive

Brandon Crawfor

no smog pump btw

Sonix

iTrader: (1)

if you absolutely need it running now, fastest thing to do is just bolt the heads back on. You could get some 416's or something, and run those in stock trim it'd make your run premium fuel, and maybe give you some extra HP due to the added CR, but just barely worth it.

If you had the time to port those (416 or the like) heads, then I'd say jump on it. But depends on how soon "soon as possible is", if that deadline can be pushed, or not etc.

F-BIRD'88

If you're lookin for a quick, cheap performance improvement over your heads you could rob the heads off a running 305 (416 or 081 casting #) and install them on your 350. They have smaller 58cc combustion chambers. This will raise the compression ratio. (more torque) Generally, if the donor 305 runs good, the heads are quite usable. If you use the 350 .015" shim head gasket (felpro 1094) you'll have close to 10:1 cr on your dished piston 350.
Then at some future date you could port them and upgrade the valve size. just be sure to take a minute and check the head casting numbers from the donor motor before ya dig in. 081 or 416 best.

Fast355

iTrader: (2)

601 and 434 castings are the best 305 castings out there. They continually put guys into the winners circle in the 305 class out here. Keep in mind that trucks in the early to mid 80s were rated at 175 HP/255 TQ and did not have the advantage of the HO spec cam, just the plain old "929" cam. You will very seldom find a 416 head on a truck, most have 601s.

Brandon Crawfor

ive heard some good stuff about 416 and 882 castings
most about the 416s came from here, and ive found a couple pairs of those for cheap,
but what about the 882s? ive found a couple of those pretty cheap too, so im just wondering what the general opinion is on either casting
thanks

sofakingdom

iTrader: (1)

416 is the early 80s passenger car 305 head. It came on most of the LG4s, L69s, and LB9s that were put into these cars up to 86. It's a good choice for your situation. It has 58cc chambers, and can be made to flow well with minimal work and larger valves (1.94" / 1.6"). For that matter, just slapping a set of them onto your motor in their native condition, will be a significant improvement.

882 is more 70s smogger garbage, just like what you've got now. 76cc chambers and the very poor early smogger chamber design. There's a reason they're cheap (well, several reasons, actually), and the reason is NOT because they're such a desirable, highly sought-after prize. Those also go in my scrap heap that I pay people to come haul off from time to time when I'm too lazy to schlepp it to the yard myself, along with the 624s and 993s and 434s, when I can't prevent them from coming into my possession in the first place.

Brandon Crawfor

but, if i put the 416s on my engine, they have a smaller combustion chamber volume, so wouldnt that raise compression?
ive been warned about that alot

sofakingdom

iTrader: (1)

Yes it will raise your compression.

That's the point.

Sonix

iTrader: (1)

Your stock motor has 76cc heads, and dished pistons, with somewhere in the range of 8.3:1 CR. Something dismal.

58cc heads, will bring it up. Do the math to find out how much, (i'm not sure the stock piston dish size, so I can't help you there), but with a rebuilder type (thicker) head gasket, it won't skyrocket your compression into unuseable numbers.

If you want, you can port out the chambers a bit to lower your compression, but just bolting them in stock, will work also. But do find the #'s, crunch them, and check for yourself on the CR.

FWIW, I have a 350, flat top pistons, decked block, .038" thick gasket, and 416 heads, with the chamberes opened up to 64cc. I have bang on 10:1. If you leave those chambers as is, but have dished pistons, non decked block, i'd guess you'd be lower than me - which is acceptable.

brian schuetta

Quickest way to get that thing running would be to have the 624s checked for cracks, if they pass, surface them and put them back on with a thin head gasket. Going with 416s to gain compression isn't the right move here with the stock cam, and they also have a smaller 1.84 intake valve. The 993s and 882s are the best flowing 70s smog heads. 624s aren't that far behind. Have run 12.90s with them on a flat-top 350 at 3400 lbs, but they need a combination around them for that. Put those 624s back on and then start looking for something to change to.

Sonix

iTrader: (1)

If those are the best, what are the worst? I mean, let me know, what ARE the worst flowing chevy SBC heads, in this era ?

Brandon Crawfor

most of this is pretty confusing, being as everyone has different opinions
but my friend has some spare heads and im tryin to get the cast number
IF theyre 416 heads and theyre good, ill use em
if not, ill have mine checked and if theyre good ill re use em
if neither are good, i dunno wtf ill do
anyway,
tips for cleaning the block for a good gasket seal anyone?
figured id ask while im at it
thanks

Sonix

iTrader: (1)

wire wheel in a drill.

Fast355

iTrader: (2)

Some of the heads had 76cc chambers and 1.72/1.4 valves.

brian schuetta

Most of the 70s smog heads can be bowl hogged to start porting and finished by hand. If I remember most are around 160-165 cc intake runners and 65 cc exhaust to start. They also mostly have 1.94/1.5 valves. Always check the valve sizes for the 1.94 intakes. All 350 type heads are 73-76 cc combustion chambers, this makes flat-top pistons , thin head gaskets, and surfacing mandatory. Remember not all stock engines have optimum deck heights either. Porting can be fun, their were some articles on this web site. The best source I saw was a VHS tape from Powerhouse that covered porting start to finish. Lost it somewhere moving or I would give more details. There maybe exceptions to what I generalized above, most of my knowledge on these heads comes from my exposure to NHRA Stock Eliminator racing. I run a 305 in Stock.

brian schuetta

Most of the 70s smog heads can be bowl hogged to start porting and finished by hand. If I remember most are around 160-165 cc intake runners and 65 cc exhaust to start. They also mostly have 1.94/1.5 valves. Always check the valve sizes for the 1.94 intakes. All 350 type heads are 73-76 cc combustion chambers, this makes flat-top pistons , thin head gaskets, and surfacing mandatory. Remember not all stock engines have optimum deck heights either. Porting can be fun, their were some articles on this web site. The best source I saw was a VHS tape from Powerhouse that covered porting start to finish. Lost it somewhere moving or I would give more details. There maybe exceptions to what I generalized above, most of my knowledge on these heads comes from my exposure to NHRA Stock Eliminator racing. I run a 305 in Stock.

Sonix

iTrader: (1)

holy cow!! hahaha, that's brutal!
I had some 993 heads on the 350 that I tore down for my build. I stole the 1.94 valves off it, back cut them, and had the seats cut in my 416's, and ran 'em that way. I practiced porting on the 993's like shaggy mentioned at the top here.

Brandon, i'd keep that to yourself . That stereotype is the brunt of many jokes here, and is somewhat amusing

Brandon Crawfor

eh, its the only job i could get,
i catch crap from ppl all the time, but at least its money

Brandon Crawfor

Dammit i always forget to ask stuff
when im cleaning the deck how much should i worry about stuff falling into the cylinders?
and should i clean out the cylinders somehow before i put the heads back on?
tryin to cover everything i can think of...
thanks

Sonix

iTrader: (1)

haha, everybody has to start somewhere with a job. Money in the bank, and the feeling of accomplishment is just peachy. But "mcdonalds" is always made fun of don't sweat it.

I'd use a scraper, or something, to get the big chunks off. Wire brush, or wire wheel on a drill if you're like me and despise manual labor. It's get it SPARKLING clean. Then use your shop vac to vacuum out the bores. Then wipe it all down with laquer thinner or acetone or brake kleen or...

I use some kind of cleaner, like a degreaser rather then the abovementioned thinners, and a piece of scotch brite, to scrube the bores. Just the top 1/2" will probably be carboned, so you can clean that up.

If you are re-using your heads as is, get some "easy-off" oven cleaner, and soak the chambers and scrub it with scotch brite or a wire wheel and whatnot. Try to get them clean. If you have no die grinder, use a dremel, and maybe a sanding drum and just clean up the roughness. Leave it shiny looking. That's a cheap fast way to help yourself out.
Put on your gasket dry, no RTV or anything, and use teflon SEALANT (not RTV) on your bolts threads. I like to use Mr gasket head bolt washers as well, with a drop of oil on the washers.

brian schuetta

Just something you guys may be interested in. Go to nhra.com, then to " Competition ", then down to " engine blue prints ". Direct yourself to what year engine you want specs on and sort by cubic inch and factory rated horsepower. Lots of information here. These specs are to build class legal Stock and Superstock engines. Head casting numbers with valve sizes, chamber cc, intake casting numbers, and more.

Brandon Crawfor

i picked up the heads from my friend today along with an edelbrock performer intake manifold
the heads are "991" castings
havent heard nething bout these in particular
nebody got any opinios?

Sonix

iTrader: (1)

check MorTec, Inc. Home Page , then double check to see if those aren't actually "993" casting, or something like that.

sofakingdom

iTrader: (1)

3998991....72-73...307/350......75cc chambers

More horse dung. 2-barrel heads from the early smog era. No better than what you've got. Not worth the head gaskets it will take to put them on.

Sonix

iTrader: (1)

holy cow, you managed to find worse heads than the 624's you have.. Congrats

Brandon Crawfor

Thanks
well at least theyre free,
i didnt have to spend anything to get them
i spose ill just put the ones i have back on
the good side: at least i have an extra pair
being as im going to start rebuilding another 350 as soon as i can find a good used block in my area, ill only be using the engine i have til round the end of next summer
as long is it works, its good