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not trying to start an arguement here I'm just curious on this matter.
it seems many say the heads aren't that great while others praise them.
any real numbers as to what either of them flow stock and how much they flow after some porting?
what are the chamber sizes and how good of a chamber design are they?
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Camel back heads, 35 years ago were a hot ticket as they were about the only real affordable performace heads available. By todays standards, they're all garbage when you see what's available in the aftermarket. Even a set of Dart cast iron heads out of the box are better than the 35 year old castings ever will be and are cheaper than trying to bring the old casting up to a good performance level.
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Originally posted by Stephen 87 IROC 882 I have no idea why people want them
Camel back heads, 35 years ago were a hot ticket as they were about the only real affordable performace heads available. By todays standards, they're all garbage when you see what's available in the aftermarket. Even a set of Dart cast iron heads out of the box are better than the 35 year old castings ever will be and are cheaper than trying to bring the old casting up to a good performance level.
Well just for argument sake Chevy High Performance magazine used those heads on a 327 (bored to 331) installed retro fit hyd roller lifters and cam (218/224 dur .495/.502 lift). It was cranking out an honest 408 hp at 5,700 rpm with peak torque at 400 lb-ft at 4,800 rpm. This computes to a stout 1.23 hp/ci on 91-octane fuel. There was a mild pocket port done to the heads and it could run 13s in the 1/4 in a 3600lbs chevelle.
These heads are mostly popular with the older guys, but they also have alot more meat then newer stock heads so can be made to flow excellent with porting(have seen over 300cfm out of 186's). I haven't really looked into pricing, but there was a time when double-humps were common and cheap from wrecking yards, so if you were an all out DIY'er, you could rebuild and port these heads for only a couple hundred bucks while putting out impressive flow numbers. With so many dart II's and vortec heads on the used market now though, these "muscle car" heads are pretty much obsolete.
but they are heavy castings, and have alot more metal to shave away to make smoother trasitions possible. They can be made to flow well with the old retirees that havfe time on their hands.
all I have ever heard about the 882's is they are a cheap low performance smogger head. they don't flow that great they can' tbe ported much cause there isn't much meat and the big combustion chamber just makes it even worse.
least that is what I heard I can neither verify or deny these claims though as I have no first hand experience
Originally posted by rx7speed all I have ever heard about the 882's is they are a cheap low performance smogger head. they don't flow that great they can' tbe ported much cause there isn't much meat and the big combustion chamber just makes it even worse.
least that is what I heard I can neither verify or deny these claims though as I have no first hand experience
and you are very wrong. Stock castings weight atleast 10lbs less then the 882 heads i have. Those are heavy castings. Much much more meat on them.
I have noticed on more than one occassion coming across 882s with a heavy casting. Of course i wont say anything here because people like to crucify you.
There were actuallty 3 times the 882 was produced.
60's 70's and 80's.
60's and 70's castings are almost identical.
But in the 80's they were trying to shoot for better smog and lighened the casting quite considerably.
Although common sence would ask why not use a different casting number, well, should you ask GM or should I? There are so many things they do that wack, one thing cant be used to point it all out.
60's and 70's castings were great heavy castings much material could be removed, and almost no fear of going too far.
but 80's castings are just like modern heads with no meat and no way to radiacally modify the heads charactoristics.
That sounds like some great news, My set of 882's are off of a '74 350. So by the sounds of it i should be able to port the heck out of these then.
Does anyone have some flow numbers for a set of early 882's that have been ported? I would like to know if i would be better off just getting some el cheapo aluminum jegs heads or something.
i can only give stock flow numbers, but they arn't very impressive. Just a little more then stoc 083 casting heads. Around the range of stock aluminum L98 heads.
But, the amount of metal available for removal on the short side radius, and the sheer mass of material to remove in all passages, allows more flow, and an eased flow through the passsages.
we had a set of stock 1.94/1.50 '462 "double hump" heads on a mild 10:1 355 with a torker II intake/cam, 750 holley alky carb big tube headers in a 2600lbs monza with a 3500stall/powerglide/4.56 combo go 10.80's over 10 years ago. since we still have these heads, they will be getting a valve job and some new springs, put back together with the small valves and put to use on a 9.7:1 357 with the comp xe274 cam, holley street dominator intake and holley 650 gas carb in a 3250lbs camaro, hoping for mid/low 12's. am i too far off in my thinking? i'll be running a 2400stall/700r4/4.10 combo and no, traction is NOT an issue with me!
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As you can see between .4 and .6 in of lift there is minimal difference. The airflow has already out flowed the passages, the valves arn't a restriction at that point. Which means porting can easily make these heads flow great numbers.
Maybe my moneys better spent on just a porting kit for the 882's i have, But i would like the aluminum as you are supposed to be able to get away with higher compressions with lower octane gas.
Just out of curiosity, whats the max lift on 882s? (without extensive mods)
Where did you get the idea that people like 882 heads or that they are desireable?
What are ya smoking?
The flow figures shown in the popular "Cylinder head flow bench database" for the 882' is infated for the true flow as produced by GM. if you were to read the origional article it states that al thou none of the heads tested were "Ported"
Some had non standard vave jobs.
Anyone that does high perf cylinderheads for a living knows you can tweek the flow numbers with the valve job contours
and shape of the valve. its easy to get 5+cfm just with a high ridding thin seat.
882's suck. they have a particularly crappy exhaust port (sort of built in EGR) In stock production form they flow worse than tpi heads. they make even less power.
TPI heads have much more performance potential.
The cast tpi heads on your motor right now may be just the hot ticket with some larger valves and thourough porting and chamber rework.
If you don;t mind applying the work nessessary they work very well.
Camel backs are quite outdated today. Althou the folklore lumbs. There are a few desireable exceptions but most are not worth reworking with so much newer stuff available.
<"The flow figures shown in the popular "Cylinder head flow bench database" for the 882' is infated for the true flow as produced by GM. if you were to read the origional article it states that al thou none of the heads tested were "Ported"
Some had non standard vave jobs.">
http://www.chevyhiperformance.com/te...98/index4.html
"This aluminum head( l98) was used on the Corvette TPI engines from the mid-Eighties until the LT-1 1992 motors were introduced. The 882-iron head out-flowed this head across the board."
from these tests the 882s are better than Dart Iron Eagles.
Originally posted by chesterfield <"The flow figures shown in the popular "Cylinder head flow bench database" for the 882' is infated for the true flow as produced by GM. if you were to read the origional article it states that al thou none of the heads tested were "Ported"
Some had non standard vave jobs.">
http://www.chevyhiperformance.com/te...98/index4.html
"This aluminum head( l98) was used on the Corvette TPI engines from the mid-Eighties until the LT-1 1992 motors were introduced. The 882-iron head out-flowed this head across the board."
from these tests the 882s are better than Dart Iron Eagles.
I remember the origional article when it first was published a few years ago.
This is what I'm talking about. The 882's do not flow that good in as produced "stock" form. They have a small intake port and a terrible restricted exhaust port..
The 441's and others like it. Have always been a better head within this class. Both from a stock perspective and in full ported form.
Just a better casting.
The 882's were never used on any factory "High Performance" engines of any merrit. Unless you call 245hp (70's L-82 350/245hp) being "hi- perf".
Most came on bread and butter motors of the era.
I've had 882 heads before. had them on a flat top 350 in my Fbird. Changed to vortecs and picked up near 100hp and chopped a full second off the same car's et. Changed to ported 305 heads with very high compression (was a blast) about 410-430hp. Same bottom end.
The 882's were dogs. I disagree with the flowbench tests on those heads in that article. They are not stock.
If you want to make over 350hp avoid 882 heads even ported 882's. there is so much better castings to use.
Yes stock L-98 aluminum heads have modest flow in stock form. But the exhaust port is much better. the chamber shape is much better. The 113 head makes more horsepower in stock form and ports up beautifully in to a rockin head.
If you don;t mind porting your own heads the L-98 alum. heads are real nice. The cast iron L-98 heads are not to shabby either. 260+cfm 200+ex with a sub190cc sized port when done.
As far as the 882 heads go the article is
It's hard to figure out how 882s and camelback heads ended up being mentioned in the same sentence to begin with... As if they're both in the same category or something.
When the only thing they actually have in common is that they both fit the SBC1 and they're both old.
One thing that's kind of too bad is that the camel back heads don't have the acc bolt holes that are needed to bolt any of the thirdgen factory accessories to the front of the engine.
Because they're a 64cc head, and with some flattop pistons and some simple port work they can deliver respectable street performance.
To make a set of camelbacks work on a thirdgen, a person would have to go to a v belt setup with the alt mounted on the driver side using a bracket that bolts onto the exhaust flange.
If someone were really motivated and had all the parts lying around the garage, it would be totally feasible.
And I'm sure it's been done too... But only in "special cases" does it make any sense.
For example, if you live in a state where there are no smog regs, and you have a thirdgen with no engine or accessories, but you have a running SBC with camelback heads already on it.
As far as an answer to the original question:
Why are camelbacks popular?
It's because during the musclecar era they were the heads that came on the Hi-Po SBC engines.
Along with 11:1 domed pistons, 2.02/1.6 valves and factory solid lifter cams.
And a lot of guys have no idea what else is available today.
Or possibly some guy is trying to sell a set, so he's just talking them up to make you think you need to have them.
Originally posted by shaggy56 I just dont understand why Chevy High Performance keep saying such good things about the 882s. Here is a completly different article with the 882s.
Maybe someone should e-mail CHP and find out why they make such false claims. The vortecs are also rated very high by them.
Thee is an old saying "garbage in, garbage out."
Seems they (the mag writers) have hashed over the same ( bad data) in numberous articles on head flow.
The writer probabily was not present for the flow tests and wouldn't know a crock of s**t from a pot of gold.
I have never flowed a 882 head but have run them and have flowed or seen flow tested may of the other heads in the database. All the other numbers look good to me.
The 882 numbers look very inflated. A non stock Hiperf valve job with a little undetectable bowl rework can easily give those numbers on that head.
I have a set of 920 castings here that flow over 230cfm but they are not "stock" I know better on this one.
Here is another good thread on the subject with lots of different opinions. Seem like thin casting and prone to cracking may have gotten mixed up along the way.
The main difference between the 882 and 993 heads in regards to cracking is the 882 feeds the exhaust crossover from both center exhaust valves as opposed to the 993 which feeds the crossover from just one. That additional heat concentrated in the center of the head is the main reason for the cracking problem.
Ya, just go ahead and get the 882's, port'em, and as long as you don't see daylight you have a kickas$ set of heads on your motor. In fact I'm gonna start searching the classfieds for '882's, they must be a great head since CHP says so, and they came on factory 400's.
You know what from all I have read their arent really any good stock productions heads. For the price of Dart heads you really cant go wrong and get some pretty healthy new castings.
from what i've read, unless the factory castings are free, they aren't worth anything...good thing my 462's were free! i'm planning on just a simple 3 angle valve job and fresh springs/hardware. hope to even reuse the valves. gonna put as small amount of money in these as possible. i'd like to eventually end up with some trickflows or other aluminum heads...maybe canfields?
On another message board someone plans to port some World S/R torquers vs. some double humps and flow bench them together. Should be interesting what they find. Ill definatly report what happens.
I was going to bid on these but i decided to save for some aftermarket heads. I just didnt want to invest in equally as good heads than i got. Dont know how good they are. I could have picked them up only an hour from me.
Maybe someone here would want them they are going cheap.
I've got a set of worked 882 castings on my first gen. I traded for them from a friend. I wanted them for their hardened exhaust seats.
I'm happy with them. No hassles and 13.20s on a 9:1 355ci 69 camaro resto-in-progress, with a $75 Summit cam kit.
He had gone 12.04 in his '68 with more everything but same 882 heads, so they ain't THAT bad.
He had ported the crap out of them, though, the exhaust ports are big and ROUND.
Double hump heads came on all the factory hot rod stuff (LT-1s, DZs, L-79s), so they were considered the coolest heads to have. For the average guy back then, they probably were.
There are still some good running motors using double humps, but there's more bang for your buck, and unleaded compatability, in the aftermarket.
Last edited by redliterunner; 10-20-2005 at 05:13 PM.
The people I hear around here that actually want them are dirt track racers who have to run stock castings. The upside? When I yank my 882 heads off my motor I can get $150 for them to some dirt dauber up the road!
Originally posted by Streetiron85 One thing that's kind of too bad is that the camel back heads don't have the acc bolt holes that are needed to bolt any of the thirdgen factory accessories to the front of the engine...To make a set of camelbacks work on a thirdgen, a person would have to go to a v belt setup...
Nope. They can be made to work.
One thing that nobody mentioned is combustion chamber shape.
How high of compression ratio can you run before detonation becomes a problem. Read about quench and turbulence .
I can only vouch for the 462 heads. Fully ported they will flow with the best of them, and you can run 11:1 with 93 octane.
They also have 3 big advantages:
1. The intake ports can be ported where the pushrods crowd the center two cylinders.
2. They can be cut to take large springs without hitting water.
3. They cost about $1000 less than a good set of aftermarket heads.
Their disadvantage is you have to run lead substitute.
Last edited by Supervisor42; 10-20-2005 at 11:59 PM.
The worse thing about the double hump heads is that they are going to erode on unleaded gas. Forget 'em if you want a long term motor.
Drilling the older 461 or 461x castings ain't all that whippy either. The material your bolted too is way too thin and almost completely unsupported. And you have to bush out your brackets to get everything to fit right.
Besides the 186 castings are about as good and have all the accessory bosses and holes. Still not happy on unleaded gas, though, and better left to the restoration crowd.
I'm surprised sometimes how much antiquated, obsolete technology gets applied to these farily modern cars.
im still learning a lot about all the chevy casting numbers but i do know they are very desirable by oval track racers. at the circle track i race at almost every street stock motor ive been through has either a set of 882's or the 441's. our engine builder who has almost 30 yrs experience likes them. when i looked up the data on them i dont know why so many track racers want them they only have a 1.94 or smaller intake and they have a 76cc chamber. although from what ive read here they must take to porting well. ive seen many circle track racers i race with just give them a quicky valve job and throw them on lol. but watching these cars go around the track they perform great. these street stock motors run up to over 6500rpm
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Circle track engine builders don't "like" 882 heads. I know first-hand.
They use them because the rules for alot of the classes require them.
186 heads are prepped for unleaded (induction-hardened seats). I believe any of the double-humps with bolt holes, are so equipped.
That pic of the heads that have been drilled and have washers stacked on them looks pretty familiar. I've been seeing that on motors on engine stands for about 30 years or more now. Funny thing is, you don't see too many cars with that rig, actually driving around. That only works on the stand. Check back in a year and see if that motor is still together like that. I'll bet not.
It's always amusing to read these threads, and see comments from newcomers to this hobby (like in the last 15 years or so) about how the old heads aren't worth a crap etc. etc. etc. Then in their next post those same people will tell you all about the "375 HP 327" they're building, without realizing, it's the same heads. Youngsters must think hot-rodding just started last week or something. Somebody on this board asked not too long ago, what did people do before AFR came into existence? I'll tell you exactly what WE did: we threw the 882s and 624s and all the old 283 and 307 heads and all the rest of that crap in the trash, and worked up a set of double-humps. I can't tell you how many motors I threw away the 882s and stuck 186s on in the 70s; with no other changes, even leaving the old crap 929 cam they had in place, it was like bolting on 50 HP (amazingly enough, actually, it was bolting on about 50 HP). Customers COULD NOT BELIEVE the difference. No change in gas mileage, no change in durability or reliability, just instant HP.
The advent of CNC casting has made the aftermarket head industry possible. It's not that nobody knew how to do it before, it's just that it cost too much to make up the molds. That's different now. The improvements in head design have been more evolutionary, little tweeks and fine-tuning here and there to improve them; where the improvements in cost are REVOLUTIONARY. It costs less now to buy a set of brand-new aluminum castings with far better properties than those old stock heads ever had, than it does to take a set of the Stone Age castings and work them up. There's NO REASON any more to race-prep a set of stockers, other than class rules. It's hardly even cost-effective to street-prep stockers, the better ones are so cheap.
I like double-hump heads, but I no longer scour the junkyards for 69 & 70 Impala station wagons to get them. I never did like 882s, and never will, and will continue to throw them in the trash whenever I get a set of them. I won't let them accumulate in a giant pile like I once did, thinking I'd eventually find a use for them; because I won't. They are a liability, not an asset, as far as I'm concerned.
So don't lump double-humps and 882s all in one group like that, it's wrong, and a sign of inexperience.
__________________ Numquam ponenda est pluralitas sine necessitate. — William of Ockham, from Quaestiones et decisiones in quattuor libros Sententiarum Petri Lombardi
Roughly paraphrased into modern English, and applied to figuring out what's wrong with your car:
The simplest explanation that fits all the facts is probably the right one.
no need to get hostile i was simply stating what i have seen. and yes i am a youngster if you wanna say that ive only been into sbc's heavily for about 3 years now. but im just stating that at the circle track i race at the rules for heads goes pretty much any stock cast iron chevy head available. no alum though. it has to be stock chevy cast iron pre 86. so why is everyone using 882 heads. honostly idk but they are. and the 2 big engine builders in my town keep using them and they are continuously making 380 to 400 hp on each motor. now for the old double hump head i have never seen a set in my life. dont know much about them or what they came on but old school hot rodders say they performed the best back like 30 yrs ago. there has been a lot of technology changes since then.
Sounds like either that's the rule; or it's a claimer class.
When I was doing motors, I avoided anything to do with those classes. The people running in them were obligated to be as cheap as possible. Frankly, for what they were forced to limit their expense to, I couldn't build something that would hold together.
Circle track classes go to a great deal of trouble to equalize the cars, and to limit the speeds. I've had to deal with a valve spring rule (1.25" OD only), cam lift rule (.390"/410" only), 2-barrel carb rule (Holley 4412 only), in fact even a class that had a claimer rule on the 4412, right-rear-tire rule (205/70-15 only), etc. Whatever rule is in effect, people try to figure out ways to circumvent. You'll probably someday see a set of heads with 64cc chambers and a "882" casting number; look closely though, you'll find that the casting number is built-up epoxy.
Trust me, the reason they're using 882 heads, isn't because they make the most power. There's something else that's more important. I've thrown too many set in the trash and replaced them with something better, to think otherwise.
__________________ Numquam ponenda est pluralitas sine necessitate. — William of Ockham, from Quaestiones et decisiones in quattuor libros Sententiarum Petri Lombardi
Roughly paraphrased into modern English, and applied to figuring out what's wrong with your car:
The simplest explanation that fits all the facts is probably the right one.
Last edited by sofakingdom; 10-21-2005 at 04:09 PM.
I've never seen a set of double hump heads with induction hardened seats. I'm not familiar with any double humps on production engines after 1970, and I don't think Chevy would have gone through the expense of induction hardening just for drill, when unleaded would not even widely hit the scene for another four years.
Also , I stole this off the web.
"882" – 333882. These heads were found on early-late 70's 350 and 400 engines. They had 76CC combustion chambers, 1.94/13.50" valves, DO have accessory holes, intake port volume is 160CC's, exhaust port volume is 60CC's. These heads are made of thinner castings and are prone to cracking as well. The exhaust port on these heads is rather weak in my humble opinion, and is not considered to be a good performance head. I have read some flow numbers on the internet regarding the 882's, and I have a hard time believing some of the flow numbers people are posting on these particular castings. I did extensive flow testing on several of these particular castings, and was not very impressed with their flow characteristics. The 441 or 487 are a much better large chamber head (in my humble opinion). The 882 intake port is very close to that of the 624, the exhaust side is where the 882 is weaker.
Originally posted by sofakingdom So don't lump double-humps and 882s all in one group like that, it's wrong, and a sign of inexperience.
only reason I lumped them together is as you said why use old school tech when you have many new options that are just as cheap if not cheaper to run a newer set of heads on a motor.
l98 heads might not be the greatest but I wouldn't say they are that bad. not like what people make the 882 heads to be. would you spend your money trying to get a set of l98 heads ported out and try to get them to work on your LT1 motor?
they might not be junk but is it really worth the effort?
and granted I still know l98 heads are nto the best by any means.
I just don't understand why I have seen people go out of their way digging and searching for these old school double hump heads when they can easily get a set of new heads.
just like I don't understand why people will go out of their way to find 882 heads when there are heads that are much better stock or aftermarket to work with.
By the time you work a set of old factory castings to make any good power you could've bought a set of aftermarket aluminum heads. They'll be more effiecient, lighter, flow better, make more power and let you run more compression.
Originally posted by redliterunner I'm surprised sometimes how much antiquated, obsolete technology gets applied to these farily modern cars.
Too much advice from grandpa.
Hey, Hey, watch it. I resemble that remark!
The main reason us old schoolers bolt those on is we ALREADY have a pair lying around and prefer to spend the $1000 on something else.
Quote:
That pic of the heads that have been drilled and have washers stacked on them looks pretty familiar...That only works on the stand.
The main reason that these fail is that the curved surface is not milled down flat and perpendicular to the head surface as shown below, and they try to use bolts in the holes instead of studs.
Care must be taken in setting the studs and putting the nuts on to the proper torque. This is not something that your average shade-tree can do with a 3/8" Black & Decker and a die grinder.
Last edited by Supervisor42; 10-21-2005 at 10:43 PM.
Unfortunately SUPER...42 most of the schmucks out there who drill early heads for accessories DO do it with a hand drill and tap, making the early Corvette guys soil their Dockers in the process, I should add.
And please don't take the grandpa dig to heart or anything. In fact, if the 42 in your handle has anything to do with your years of youth, then I've got about 5 on you.
I'm just surprised how so many people throw the baby out with the bathwater on these cars. I, as much as anybody, see the acute need for increased power, but I personally can't bear to give up the great benefits of EFI or the ability of later engines' to be economical and relatively enviro-friendly. (Of course, I have to drive my P.O.S. to work everyday)
LS1 is a great example. If you've never driven one...do it. Fabulous power, clean, and hassle free. Or any later Cobra, (sorry guys). Spectacular!
And yeah, I know it'll wind up costing me a bunch more $ to go as fast as you, if I ever do. The cost of hot rodding the TPI is stupid compared to a nice double pumper and an air gap.
Originally posted by Supervisor42 Nope. They can be made to work.
You're right about that... I should have said something like "you have to know what you're doing to get them to fit"
But then I would have felt obligated to explain, and your pics do a better job of explaining than I could ever do.
I'm an advocate of using recycled SBC parts whenever it's practical.
In this era of engines that are vastly more sophisticated, for many guys, it makes more sense to keep SBC1 projects "lo budget" and sink the big$$ into an LS1 swap.
Of course that all depends upon someones resources and what their overall personal goal would be.
I wouldn't go out and purchace a set of camel heads or smogger heads, but if I had some I might consider figuring out a way to make them work.
For example, some milled down smogger heads combined with flattop pistons and a zero deck block can provide enough compression in a 355 or 383 to give acceptable performance when a smallish cam is used. Especially if the application is a daily driver econo car with some pretty tall gearing.
Or if someone wants to build their engine in stages and needs some cheap heads to keep it on the road, til some better heads can be bought.
<--- Small Block Chevy
