1983Zsled

I have a 350 block casting #14016379, with a stamp of V0419800.
The research I have done denotes a 1977 to 1979 over the counter replacement engine. the original owner says it came out of a 3/4 tonne truck.
It has a four bolt main, and the heads that are on it now are 462624. According to the research I have done they don't appear to be a good head. I haven't pulled them yet to know what the valve sizes are but they are probabaly the 1.94 Int and 1.50 exh. Any info on Horsepower rating for this engine? Mortec doesn't list any.

I will rebuild the bottom end, and I want to put on the casting # 354434 heads 1975-79 262/267/305...60cc chambers to increase the compression ratio.

Does anyone know what the int. and exh sizes are on these?

I will use a intermediate cam, and Gm aluminum intake #14057053
with the stock Rochester carb.

As usual on a budget, otherwise I would look at the vortec heads....

Is there anybody out there who has done this?

Thx

five7kid

iTrader: (14)

Horsepower rating - practically an oxymoron, about 145 net.

624 heads on 350 = low compression pig. 434 heads on 350 = higher compression, ping-prone pig.

1983Zsled

So what's the answer? Scrap both ideas and look for a vortec head system and cam?

I used the 305 heads and a LT1 Cam on a 350 - 010 block for a half mile oval stock car. They did ping with normal octane fuel but not on 94.
This did create enough HP to race anyone down the front and back stretch.
I'm not sure what kind of HP it would produce.

The LG4 I have now is what 145 hp. I want about 300 hp out of this 350.
Any suggestions.

five7kid

iTrader: (14)

'83 LG4 should have 416 castings on it. Those are decent heads. 1.94" intake valves (and 1.60" exhaust if you're up to it), basic bowl cleanup, good valve springs, and they'll support a dished piston 350 very nicely.

82Five-O

I'm about to run the same setup five7 just mentioned, except my bottom end has flat tops.

1983Zsled

Is the valve size on the 434 heads too small, Doesn't the increased compression help to produce more power?82Five0 - What pistons are you running? Any idea of the compression?

sofakingdom

iTrader: (1)

The 434 heads are a crappy casting, for reasons other than valve size.

They are one of the "lightweight" castings, with the weird "siamesed" exhaust crossover arrangement, which creates lots of hot spots and thin places which are HIGHLY prone to cracking. Putting larger valves in them just about guarantees that they'll crack, as does over-enthusiastic porting.

Here's some SBC heads that share that casting profile. Note the thickness (I use the word loosely) where the piece broke out.



416, 601, or 081 are the 305 heads that work well. Avoid the 434s, and ANY swirlies (191, 187, 193, etc.).

305 heads on a flat-top 350 is a recipe for a pinging, detonating, premium-gas-sucking, oil-burning, short-lived, timing-challenged slug. I would not do that.

82Five-O

the valve size is adequate, i intend on making up for any losses there with a little higher lift on the cam. I am running keith black flat tops. The numbers say my CR should be around 9.5 to 1. Sofa kingdom is right. there is a big risk of cracking when it comes to these heads, so i won't be running anything over 93 octane. other than that, it should be fine. just do some research and know the characteristics of the heads you are putting on your engine.

Sonix

iTrader: (1)

...Unless you deshroud the chambers on the 305 heads to increase the flow around the valves. I ended up with 64cc heads, with my flat tops that gave me 10:1 CR on the nose.

Pat Hall

iTrader: (31)

305 heads on a flat-top 350 is a recipe for a pinging, detonating, premium-gas-sucking, oil-burning, short-lived, timing-challenged slug. I would not do that.[/QUOTE]

I definitely second that statement! Been there, done that. I cracked a 441 casting head due to a stuck thermostat on my 355 years ago, and I slapped a set of 58 cc 305 heads on it just to get me by until I had a set of fuelies (462 casting) redone. My motor had flat top pistons and was zero decked, so the CR was probably hovering right around 11:1. That poor motor was pinging like mad! Btw, a lot of the 305 heads, especially the ones from the 1970's, have intake valves smaller than 1.94.

five7kid

iTrader: (14)

I believe no 305 head had bigger than 1.84" intake valves from the factory. 3rd gen 305's all got 1.84" intake valves - no exceptions. The early passenger and truck 305's got 1.72" intake valves (so did truck 350's for a long time).

If you are looking for 1.94" intake valves in a 305 head, you'd better have asked for them from your machine shop.

327_TPI_77_Maro

iTrader: (8)

You'd be miles ahead getting some real heads to start with. Dart Iron Eagles or World Sportman IIs are not expensive heads.

82Five-O

the 624 heads had 2.02 intake valves and they came on my 83 305 i still got em. It was in a truck tho.

Sonix

iTrader: (1)

I'm pretty sure no SBC ever came with 2.02 valves from the factory, purely aftermarket. (With the exception of some 1969 era cars probably).

327_TPI_77_Maro

iTrader: (8)

That is a very incorrect statement.

From Mortec.com:

462624.....75-86...350/400......76cc chamber, 1.72/1.5, 1.94/1.5 or 2.02/1.6 valves

Some more SBC 2.02 factory heads from Mortec:
3973487....71-72...350..........1.94/1.5 or 2.02/1.6 valves, was also used on '71 350/330hp LT1, 75cc chamber
3973487X...71-72...350..........1.94/1.5 or 2.02/1.6 valves, 75cc chamber
330545.....73......350..........76cc chamber, 2.02/1.60
333881.....74-75...350..........76cc chamber, 2.02/1.60

All smog era stuff too, not just 60s factory heads

Sonix

iTrader: (1)

Well i'll be damned. I wonder where I got that info then...?

five7kid

iTrader: (14)

And with the possible exception of the 487's, all with be out-powered by 416's with 1.94" intakes.

327_TPI_77_Maro

iTrader: (8)

I compared stock 487xs to ported and plished 416s on my 327, and the difference in high rpm power was very noticeable. The MAF would peg above 5200 w/ the 487x heads, but it never pegged the maf w/ the 416s even at 6k+. Bigger valves most likely would have helped the 416, but I just jumped to aftermarket iron heads, rather than spend a ton of money at a machine shop putting bigger valves in 305 heads. Machine work is so expensive nowadays that unless you can do the work yourself or have a friend do it, a new pair of $800 2.02/1.6 64cc 200cc runner iron heads starts looking like a really good alternative.

five7kid

iTrader: (14)

With a mild cam and stock LG4 intake the originator is talking about, those heads would be overkill. If he can't afford Vortecs, then he won't be able to afford 200cc heads. Agreed, machine shop work adds up fast.

1983Zsled, to be honest, you're probably better off sticking with the 624's until your budget allows for doing it all the right way.

Sonix

iTrader: (1)

Out of curiosity, which ones in particular are you talking about? I'm always interested in inexpensive aftermarket larger port heads

1983Zsled

Ya, I agree Lots to consider. I still might take a run at a vortec 906 casting head if Santa is good to me!!! Otherwise I will stay with the 624's.

I was looking locally ( Southern Ontario) and found a set of 327 heads casting 3890462 2.02 int, and 150 exh fresh rebuild with crain performance liffters 99277, full set of rocker arms, Weiand Stealth Intake, Moroso aluminum valve covers, The Guy wants $600 Canadian for the package?

I think those are good heads.

thx for the advice guys

five7kid

iTrader: (14)

Need to be aware of the lack of accessory bolt holes on earlier SBC heads.

327_TPI_77_Maro

iTrader: (8)

Sonix, look on ebay at new World Products Sportsman Iis, and Dart Iron Eagle Platinum heads. The Dart heads cost a little more but have a 5 angle valve job and bronze liners (both good things) right out of the box.

1983 sled, also be careful, because the old heads do not have hardened valve seats, unless someone added them. Lots of the time, shops "rebuild" old heads by slapping a stone valve job on them and sending them on their way. If the seats are not hardened, they are probably not going to last very long. And oh yeah, accessory bolt holes, like was mentioned, will be a big problem if the heads don't have them.

RIPPERACE

I agree that the Dart and World Products heads are the bee's knees for the price. I have used the World Products heads on my own engine build for my T/A. I can't really think of any drawbacks to buying a set of these. You bolt them on, install your rockers, and that's essentially it. When you figure in the cost of finding a good set of used heads, new springs and keepers and possibly valves, and then getting them machined, you could be in for just as much as you would for a set of brand new World heads or Darts.

Also check out Northern Auto Parts as they sell these World Products heads at about the best price I've seen. You can buy them either complete or as a bare casting with a kit that contains all the same parts as the fully assembled heads. I think you save yourself about 60 or 70 bones by assembling them yourself.

On a side note, I know they weren't a real performance type head, but regardless....Stay away from the 882 casting numbers too. We refer to them as "Windsheild heads" or "Anchor Heads", cuz thats about all they're good for. Either toss them through someones windshield your mad at, or use them as boat anchors. They had a bad tendancy to crack. They were a common head in the mid 70's if that isn't enough to keep you away from them too.

Just my couple of dimes of info for ya to bite on....Ripper

kad5118

how do you guys think the 601 or 416 heads work on a stock 91 l98 with 137,000 miles on it.

327_TPI_77_Maro

iTrader: (8)

A stock 416 head is basically a perimeter bolt, smaller valve version of an L98 head. Stock for stock that is definitely not an upgrade. The 083 L98 heads, if your engine is stock, are a decent gen 1 head. I would port your 083 heads, or buy aftermarket heads, before I started messing around with 305 heads. There is so much available now, EQ has some hybrid vortec heads that start around $600 fully assembled and they are really nice castings.

kad5118

how are these hybrid vortec heads that you speak about can fit the standard non vortec intake bolt pattern.

327_TPI_77_Maro

iTrader: (8)

They are drilled for, and the intake runners are configured for, gen 1 intakes

http://www.ebay.com/itm/NEW-CHEVY-EQ...1c5df0&vxp=mtr

^ The 083 head is specifically mentioned as being replaceable by that new Vortec hybrid head.

Just one option. At the price point you can get stuff like that though I would not be messing with 305 heads on a 350. I built a set of EQ vortecs for someone else and the casting quality was extremely good, way better than a factory type head.

sofakingdom

iTrader: (1)

If the heads fit a non-Vortec intake, they are NOT "Vortec" heads, no matter how large of a typeface they printed the BUZZWORD in to spice up the ad copy.

"Vortec" is GM-speak for "we moved the intake ports".



THE WHOLE POINT of "Vortec" is, they raised the runner, to give the air/fuel a straighter shot at the back of the intake valve. Therefore if the ports aren't raised, they're not "Vortec".

As someone with considerably more experience than me in taking advantage of gullible people once said, there's a sucker born every minute, and 2 more to take advantage of him. Looks like you just found the advantage-taker. Don't be the sucker.

kad5118

I dont think these heads work with non vortec style tpi intake with out major work.

Johnny Blaze

iTrader: (15)

Look at the link,

This cylinder head is based on the EQ Vortec cylinder head that was featured in the popular “Budget Sledgehammer” build in Popular Hot Rodding magazine which produced 447 HP for under $3,500.

EQ Part #CH350G features ’87-’95 intake bolt pattern with center bolt valve cover mounting holes. The head features 64cc combustion chambers, 176cc intake runners capable of excellent flow and velocity, standard 1.94 in. diameter intake valves and 1.50 in. exhaust valves. The intake port opening for the EQ CH350G/H is designed like the 68-95 intake ports to provide easier port and gasket matching.

The Vortec Hybrid heads are Australian manufactured and feature a thicker .4375 deck for greater strength, and hardened DuraBond exhaust seats for improved durability. Both the CH350G and H should be used in pairs when replacing OE heads (083, 191, 193, 217 and 810 castings) and are available bare or assembled. To ensure the highest quality, EQ conducts a 25-point quality inspection on every new cylinder head shipped. The price stated is for one head.

Johnny Blaze

iTrader: (15)

Those "Vortec Hybrid" heads are coll! Can't believe I haven't seen them mentioned.

The chambers are deffinatly vortec shape. These will be great for tpi guys that don't want to spend $500 on the crappy vortec base!

Johnny Blaze

iTrader: (15)

While a lot of what makes vortecs great is the raised runner, the cumbustion chamber is also unique and credited for the vortecs effecincy. These "hybrid' heads have the vortec chamber.

Johnny Blaze

iTrader: (15)

I just noticed this is another "ZOMBIE THREAD!"


I doubt the op is still working on this build.

kad5118

yea i read that engine build that popular hod rod did using those head.Yea i got that part.But the intake that was used was a (vortec) cross wind intake not a non vortec intake.Does anyone else finds that wierd or are there any one that are using those head right now on a non vortec tpi intake and could vouch that these hybrid heads would actually work with a non vortec sbc intake.

Johnny Blaze

iTrader: (15)

ReRead it and look at the pics.

These are NOT the same heads used on the Popular Hot Rodding build. They are BASED on that head.

The Intake Port shape and bolt pattern is based on the 87 up heads. Look at ths pics, there are no bolt holes for a vortec intake manifold.

Thats why they are calling these Hybrids. Bascially its an 87-95 head with a Vortec Cumbustion chamber.

Johnny Blaze

iTrader: (15)

See Bold

327_TPI_77_Maro

iTrader: (8)

Johnny is correct. The hybrid heads have a gen 1 type intake runner, larger than stock intake runner size, with a fast burn style combustion chamber. No this is not exactly the same thing as a factory vortec head. Yes it is a better idea than using a regular gen 1 head. The EQ heads are already machined for higher lift and standard springs w/ damper. I don't sell these or have any interest in them, and yes there are better flowing heads out there if you want to spend a lot of money, but a head like this is a very good alternative to delving into old used gen 1 heads.

kad5118

oh ok so those were not the same heads that was in the magazine.

Johnny Blaze

iTrader: (15)

I know, thats what I said. That is also what is said in the ad.

"This cylinder head is based on the EQ Vortec cylinder head that was featured in the popular “Budget Sledgehammer” build in Popular Hot Rodding magazine which produced 447 HP for under $3,500"

kad5118

oh ok well i think i may buy me a pair of these heads to replace my stock l98 heads

Johnny Blaze

iTrader: (15)

Sounds like a good plan. I amy do the same. These would be perfect for a mild daily driver build.

sofakingdom

iTrader: (1)

The chamber shape is about .000000000001% of what makes "Vortec" heads, "Vortec".

The other, IMPORTANT and SIGNIFICANT, 99.999999999%, is th eport location.

"Vortec" heads that don't have the ports in the "Vortec" location won't run like "Vortec" heads.

They're SUCKER BAIT. Don't fall for it.

And yeah, it's a necro thread; somebody new re-opened it to ask about putting 305 heads on a 350. Prolly the same guy that's been asking that on every forum and opening every thread with the word "head" in it and even starting a coupla new threads. Then somebody else spammed him with the "sucker ripoff" Chinese heads. Oh well.

Johnny Blaze

iTrader: (15)

Tell us how you really feel

I'd still say those heads are a great option for a mild tpi build. From what I have found if you want to keep your stock tpi base, the only option are factory heads, these at $600 or Summit aluminum ones at $900. So for a budget build, I think these are good, and would be a nice improvement over stock.

Johnny Blaze

iTrader: (15)

So the one thing I noticed in the eBay ad for thr "hybrid vortecs" was a lack of lift info.

I sent the seller a message asking "what is the max lift the heads are capable of and what are the valvespring specs?

The reply i got was,

"these are stock heads, with stock lift and stock valvesprings."

I'm still interested in these and will look for these specs, but I won't be buying them from that vendor!

It appears these heads have been around for almost 3 years and have been used by some people here.

sofakingdom

iTrader: (1)

Possibly so...

Too bad they polluted a potentially decent product that might have some degree of merit on its own (or not... I don't know) by slapping the BUZZWORD on it to confuse the less informed and entrap the gullible. Even if THE PRODUCT itself were any good, I would refuse to do business with the seller however, on the basis of the lie.

kad5118

I have seen the price of those heads which are decent.but at the same time for that amount i can find me a used 5.3 vortec or even a 4.8 vortec and built either of them for high rpms and power.so i am really rethinking this situation carefuly before i move foward on my thoughts.I plan on doing a lsx swap any way

Johnny Blaze

iTrader: (15)

These guys seem to think a lot of the vortecs sucess is in the chambers.
http://speedtalk.com/forum/viewtopic.php?f=1&t=21448

Pat Hall

iTrader: (31)

This post is so long I didn't check every reply to see if this was mentioned or not, but one MAJOR problem with those 305 heads is they have smaller valves than the average 350 head, so you'd have the added cost of having them hogged out for larger diameter, 350 style valves. Then there's the port sizes. While they probably flow more than enough for the average 305, they're probably a pretty good breathing restriction on a 350. Really the only advantage they offer on a 350 is the typical 58cc chambers give you a good boost in compression, but by the time you spend the time and money to install the larger valves and hog out the intake/exhaust ports, it just ends up being a waste of time, especially when for the same amount of money spent in the end, there's vastly better choices of head to use, such as the Vortec styles mentioned.