general head question
Thread Starter
Racer
Joined: Feb 2012
Posts: 421
Likes: 27
From: Harrisburg PA
general head question
Which heads have the most performance potential:
I have the following:
2 pair 882's
1 pair 997's
1 pair 041's
I know that aftermarket would certainly be better, but I've got the above sitting on the shelf.
I could build the bottom end as needed to get to about 10:1 compression (where I want to be) on the 400 block I have (817 casting), so the combustion chamber size is somewhat irrelevant (at least as far as compression ration).
I currently have a 406 (509 casting in my '67 camaro), so this would be possibly for my '77 vette. The 406 in my camaro is such a fantastic performer for me...it has dart iron eagle heads, and an HR282 from comp cams. I'd be looking to go with a similar cam in the 817 casting...how disappointed will I be with one of the above pair of stock heads on a motor that is otherwise about the same?
Which pair has the best upside?
I have the following:
2 pair 882's
1 pair 997's
1 pair 041's
I know that aftermarket would certainly be better, but I've got the above sitting on the shelf.
I could build the bottom end as needed to get to about 10:1 compression (where I want to be) on the 400 block I have (817 casting), so the combustion chamber size is somewhat irrelevant (at least as far as compression ration).
I currently have a 406 (509 casting in my '67 camaro), so this would be possibly for my '77 vette. The 406 in my camaro is such a fantastic performer for me...it has dart iron eagle heads, and an HR282 from comp cams. I'd be looking to go with a similar cam in the 817 casting...how disappointed will I be with one of the above pair of stock heads on a motor that is otherwise about the same?
Which pair has the best upside?
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
The 882s are very valuable to marinas. Seems they can really keep a boat from drifting in sand bottom lakes. The valvestems hunker-down into muck-bottoms also.
Big chambers, little valves, little ports, little flow, small spring pockets, low compression smog heads that are not worth putting any money into. Some people have machined the seats for 2.02 and the 1.60 valves but the ports are still the bottleneck of good flow. If you put any decent cam lift stress on the rocker studs they can bend, break or pull out of the head.
Pitch them.
Don't know about the others.
Big chambers, little valves, little ports, little flow, small spring pockets, low compression smog heads that are not worth putting any money into. Some people have machined the seats for 2.02 and the 1.60 valves but the ports are still the bottleneck of good flow. If you put any decent cam lift stress on the rocker studs they can bend, break or pull out of the head.
Pitch them.
Don't know about the others.
Last edited by HeadsU.P.; Mar 1, 2020 at 07:07 PM.
Le Mans Master
Joined: Oct 2007
Posts: 7,442
Likes: 967
From: Tennessee/Rhode Island
The 882s are very valuable to marinas. Seems they can really keep a boat from drifting in sand bottom lakes. The valvestems hunker-down into muck-bottoms also.
Big chambers, little valves, little ports, little flow, small spring pockets, low compression smog heads that are not worth putting any money into. Some people have machined the seats for 2.02 and the 1.60 valves but the ports are still the bottleneck of good flow. If you put any decent cam lift stress on the rocker studs they can bend, break or pull out of the head.
Pitch them.
Don't know about the others.
Big chambers, little valves, little ports, little flow, small spring pockets, low compression smog heads that are not worth putting any money into. Some people have machined the seats for 2.02 and the 1.60 valves but the ports are still the bottleneck of good flow. If you put any decent cam lift stress on the rocker studs they can bend, break or pull out of the head.
Pitch them.
Don't know about the others.
The 882's are not really that bad for flow, it's the large chamber 76CC that was more of an issue and the tendency of the heads to crack with high heat/temperatures....
Last edited by jb78L-82; Mar 1, 2020 at 07:48 PM.
Race Director
Joined: Mar 2017
Posts: 11,906
Likes: 4,479
From: Virginia
I don't have a dog in this fight, but perhaps you can sell them to someone who wants them (eBay?), and use the proceeds to buy the heads you want.
The new AFR Enforcers looked promising:
https://www.corvetteforum.com/forums...assembled.html
The new AFR Enforcers looked promising:
https://www.corvetteforum.com/forums...assembled.html
Le Mans Master
Joined: Oct 2010
Posts: 6,922
Likes: 839
From: melbourne florida
2023 C3 of the Year Finalist - Modified
The 882 with the 2.02 valves with some bowl work aren't that bad. If you can get 10-1 compression with those big Chambers you may be ok. If they haven't cracked in.40 years they will likely be ok.
But.aftermarket heads are easier and better. And possibly cheaper.
But.aftermarket heads are easier and better. And possibly cheaper.
Race Director
Joined: Jan 2000
Posts: 13,014
Likes: 2,257
From: Corsicana, Tx
2020 C2 of the Year - Modified Winner
2020 Corvette of the Year (performance mods)
C2 of Year Winner (performance mods) 2019
2017 C2 of Year Finalist
Sell them all and buy a set of basic Brodix for less than $1K. They were on sale recently. A 400 needs airflow.....those heads are weak on a 350....
JIM
JIM
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Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Apparently the 041 ones are 64cc chambers. So those will be the best of those 4 sets. They are the best CASTING of the 3. They could be in the worst shape of all of your heads. Do you and a valve Spring compressor yet? Then go buy 1. Find out what the valves are like find out what the guides are like. If you need to put guides or liners into all 16 guides you're getting into the price of a new set of aluminum heads. Basic valve seat leak test. Lay the head on it's side intake or exhaust ports up. Fill the ports with water. Look at the valves. If a little bit of water is dripping out it's one thing. If it's peeing out that valve needs a valve or serious valve work or a seat. Check all 16. (In your case, all 64.) Then pull out the valve Spring compressor and break the heads down and see what the seats look like the valve faces look like and how loose the guides are.
Last edited by derekderek; Mar 2, 2020 at 07:36 AM.
Le Mans Master
Joined: Mar 2004
Posts: 7,458
Likes: 1,484
From: Little Rock AR
The 041's are some of the best factory production heads. That said, they will never be popular for nostalgia reasons because they do not have the double humps. Double humps will always win the nostalgia race. Those 041's are the same as the double hump 186's from a functionality standpoint but they lack "the look", so they loose. If you can't win with nostalgia, you need to win with cost. If the heads need a lot of rework $$$, you should probably sell them. Maybe a circle track racer would still need them.
I have a pair of old iron double hump heads on my bench right now and need to make the same call. They will probably be saved because they have collector value but it might end up costing me more than they are worth. I don't even have any plans to use them at this time but I want to have them done and bagged just in case. It gets harder and harder to do this stuff every day with the shops going out of business. They say it is a hobby but maybe it is a sickness -LOL.
Once the price gets too high to keep old iron, the aftermarket heads start looking better. Lower cost, high flow and more efficient chambers. Hard to beat that.
I have a pair of old iron double hump heads on my bench right now and need to make the same call. They will probably be saved because they have collector value but it might end up costing me more than they are worth. I don't even have any plans to use them at this time but I want to have them done and bagged just in case. It gets harder and harder to do this stuff every day with the shops going out of business. They say it is a hobby but maybe it is a sickness -LOL.
Once the price gets too high to keep old iron, the aftermarket heads start looking better. Lower cost, high flow and more efficient chambers. Hard to beat that.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
I don't have a dog in this fight, but perhaps you can sell them to someone who wants them (eBay?), and use the proceeds to buy the heads you want.
The new AFR Enforcers looked promising:
https://www.corvetteforum.com/forums...assembled.html
The new AFR Enforcers looked promising:
https://www.corvetteforum.com/forums...assembled.html
Last edited by HeadsU.P.; Mar 2, 2020 at 12:56 PM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
on east coast, many circletracks have popular restricted classes where OE iron heads with 1.94/1.5 & NO LESS than 70cc are mandated. Very common that 487, 882 & 997 etc are milled to 70cc for that specific reason. However, old worn stock don't bring much. 041 chamber too small for that anyway and there's so many better options for small chamber. None of those heads flow good enough for a sporty 400.
Le Mans Master
Joined: Feb 1999
Posts: 8,351
Likes: 75
From: Tampa Bay FL
Well, reminds me of a past story. I too hated to scrap those 882s out. Put them on Craigs in a 200 mile radius area, for $50. Valves, springs, retainers, etc. Not cracked, but two bad rocker studs. Several weeks go by. Now $40, then $25. Not one response or offer. Donated to scrap-iron fund raiser. There are thousands of them out there or used to be. No body wants them.
Once the aftermarket stepped up, there was no going with the aged heads. With all of the better flow numbers, there was no sense staying with the old castings. The orig heads on my '80 L48 were the thin-wall 624's. When I removed in 1999 (engine rebuild and 882's installed), all of the exhaust seats were cracked and guides were worn. Was not worth restoring the 624's.
As others have suggested, research the aftermarket for a suitable iron head. Had I to do it over, I would have gone with the 64cc chamber, 180cc runner Iron Eagle. I have the 72cc chamber but it flows and I've had the bowls blended in most recent head refresh.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,022
From: New Braunfels Texas
Do not waste your money on GM heads unless you need to have a nostalgia look.......GM heads were and still are, the most pitiful thing about a Gen 1 small block....hands down.
The 66' in the Avatar had the original camel humps on it......$2000 dollars later, they flowed what an Edelbrock RPM head flowed. $2000.....will buy heads, rockers, pushrods, head bolts, valve covers and gaskets......see where I am coming from?
That said.....I have ported a set of 882's and with a mild cam on a low compression 350 in a 72' Nova it ran 13.80's with a 3.73 gear.........that is not that fast really......a set of real heads would have been worth another 50-60 horsepower.......car had ***** torque though.....
Jebby
The 66' in the Avatar had the original camel humps on it......$2000 dollars later, they flowed what an Edelbrock RPM head flowed. $2000.....will buy heads, rockers, pushrods, head bolts, valve covers and gaskets......see where I am coming from?
That said.....I have ported a set of 882's and with a mild cam on a low compression 350 in a 72' Nova it ran 13.80's with a 3.73 gear.........that is not that fast really......a set of real heads would have been worth another 50-60 horsepower.......car had ***** torque though.....
Jebby
Melting Slicks
Joined: Apr 2001
Posts: 3,399
Likes: 278
From: Olmsted Falls, Ohio
The problem with 333882 1975 and later is that they are VERY thin walled with 2 crossover exhaust runners. They get hot. They will crack.
On the other hand my 75 882 heads were good until last year when the chamber cracked and blew away causing a hydrolock.
Why take a chance on thin walled heads? Why spend any money on them? Dump them.
If they are on your car they are probably coming to the end of their life.
On the other hand my 75 882 heads were good until last year when the chamber cracked and blew away causing a hydrolock.
Why take a chance on thin walled heads? Why spend any money on them? Dump them.
If they are on your car they are probably coming to the end of their life.
Thread Starter
Racer
Joined: Feb 2012
Posts: 421
Likes: 27
From: Harrisburg PA
Thanks, all...I appreciate the input.
I prefer to run iron heads. I do love the iron eagles I have on my current 400.
What are the best budget minded flowing iron heads out there?
Like I said, I know darts are good (from experience). World products? most aftermarket heads seem to be aluminum these days.
I prefer to run iron heads. I do love the iron eagles I have on my current 400.
What are the best budget minded flowing iron heads out there?
Like I said, I know darts are good (from experience). World products? most aftermarket heads seem to be aluminum these days.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,022
From: New Braunfels Texas
Thanks, all...I appreciate the input.
I prefer to run iron heads. I do love the iron eagles I have on my current 400.
What are the best budget minded flowing iron heads out there?
Like I said, I know darts are good (from experience). World products? most aftermarket heads seem to be aluminum these days.
I prefer to run iron heads. I do love the iron eagles I have on my current 400.
What are the best budget minded flowing iron heads out there?
Like I said, I know darts are good (from experience). World products? most aftermarket heads seem to be aluminum these days.
I put some Iron Eagle 200's on my friends blown 355 Highboy Deuce and it is a freakin beast....those heads were to go on my own 406 but I went aluminum 200 Platinum Dart.
Jebby
Last edited by Jebbysan; Mar 3, 2020 at 07:01 PM.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
some other iron
Engine Quest
Chevy Bowtie
Depends on which part of the country the circletrack guys are racing ... some region's tracks don't have a class which permit aftermarket iron ...
or aftermarket aluminum ...restrictions, rules & conventions vary widely depending upon region.
e.g. bought a fresh 377 motor from a nice dirt car which had been brought from FL to SC ... chassis got modded & adapted to SC rules but No SC track (asphalt or dirt) permits 377. .. even w/ a weight penalty. I kept some of it & parted out some. Anybody in market for forged Manley hi-dome pistons for 6" rod 377 ? Same for its WP Sportsman II heads ... won't work for regional CT rules ... but sold to a guy with a hot boat. Keeping its fresh +30 400 block, Manley platinum 6" I-beams & steel GM 3.48" crank, hi-$ kicked out shallow pan, crane gold rockers. Heads' sale pretty much covered what I gave for whole motor; sometimes lady luck is favorable.
Engine Quest
Chevy Bowtie
Depends on which part of the country the circletrack guys are racing ... some region's tracks don't have a class which permit aftermarket iron ...
or aftermarket aluminum ...restrictions, rules & conventions vary widely depending upon region.
e.g. bought a fresh 377 motor from a nice dirt car which had been brought from FL to SC ... chassis got modded & adapted to SC rules but No SC track (asphalt or dirt) permits 377. .. even w/ a weight penalty. I kept some of it & parted out some. Anybody in market for forged Manley hi-dome pistons for 6" rod 377 ? Same for its WP Sportsman II heads ... won't work for regional CT rules ... but sold to a guy with a hot boat. Keeping its fresh +30 400 block, Manley platinum 6" I-beams & steel GM 3.48" crank, hi-$ kicked out shallow pan, crane gold rockers. Heads' sale pretty much covered what I gave for whole motor; sometimes lady luck is favorable.
Le Mans Master
Joined: Mar 2004
Posts: 7,458
Likes: 1,484
From: Little Rock AR
I have Iron Eagle 200's on my L-82. They worked out nicely to increase the compression and flow. I would probably use them again. Need to cut the valve cover rail down about 1/4" if you want to completely hide them from a purist. The EGR valve would not fit "as built". 