The old 993s were about the best of the open chamber sbc heads. John Lingenfelter flow tested a bunch of production heads back in the 80s and came to that conclusion. He ported and milled them & used them on 383 builds. He was a pretty sharp dude. That was back before the hundreds of sbc head choices we have now.

Back in the early 90's my first sbc build had cast iron #461 heads and they were factory 23° 2.02 int 1.6 exh and I had screw in studs done 665 int 675 exh and the 383 sbc they were on with a 175 shot was a fun little street deal back then when I first started. Then in 2000 I bought my first aluminum heads with 2.12 int 1.6 exh shaft rockers, port matched super Victor Jr. Intake had a 250 shot and then went to a blower. Man bring back memories. Great video

Bring me back to my 441 glory days....thanks! Wow things have come far.

The rotator was for unleaded fuel compatibility. I know because I read everything in those days. My first new car was a 1972 Chevy Nova, 350, 3 on the floor. $2850 out the door. It had those 882 heads, which I still have somewhere. They got replaced with a pair of 1970 400 heads which had the closed chamber, and a larger 1.6 exhaust valve to go with the 1.94 intakes. The 3863151 350hp 327 cam, $38 at my Chevy dealer, really woke that engine up.

O-ring seals the retainer to the stem to stop the gap in the locks letting oil run down the stem and puddle on the top of the guide.

I had a set of stock 882 with 2.02 1.60 off my 1975 L82 corvette. Had screw in studs and guide plates also

Thank you for your enlightening videos and spending your time to contribute to the community of those interested in learning about cylinder head improvement.

Hey Eric, Tim here, i aint a sbc guy, but this vid, shows valid difrences, and i just thought this was a KILLER tech vid........TY sir for all ur time and effort.......PEACE to you sir!!!

The "Cheater" screw in studs are (the ones we use) Pioneer RM-348, they don't have the hex, simply pull the pressed in studs, tap for 7/16-14, was a cinch on the SERDI, double nut and screw them in with a dab of LocTite.

A throw back to 1993. Love it.

Brings back good memories, mostly, of building “purestock” engines:) 882’s we’re everywhere and as a kid I definitely got into grinding them with my Dremel and shopvac dust control in my parent’s basement. Stud pinning was the the pretty common affair with the occasional use of ‘cheater’ studs that threaded in but didn’t have a nut shoulder so you had to double nut them to tighten down. Sometimes I was lucky enough to work on “camel humps” for the Street stock guys! When I worked in the shop we used liners to bring back guides. The process had a bunch of steps but went really quick with the right tools. Something like: bore guide, press in liner, cut length, broach and finally ream to size. Then put the pilot in and grind the seats. Grind and Reface valves on the Sioux City. Probably about 30mins a head then off to the Jetspray washer before spring height check/shim and assembly.

I wish this was around 25 years ago.... damn

Thanks Eric, always appreciate your input on even the worst cast iron SBC heads!

The 1973 Corvette L-82 had 882 heads with 2.02 int. & screw in studs & the same forged shortblock as 1970-1972 LT-1's.

Thanks for the info been looking for these numbers on the 487X for a long time.

Makes me miss my 400 I built 8 years ago, stock 2 bolt 400 out of the local pick and pull a comp tow cam z28 valve springs and 882 heads slightly ported with 1.62/2.02 valves 1.6 rockers, flat top pistons, aluminum Camaro intake manifold with a q-jet through stock manifolds it passed ca smog in a 78 c10 350, it was definitely chocked up past 5500rpm but made tons of torque with a 2500 stall 4.56 gears and 31in tires, it would burn the tires until you let off

I've had good results from porting 487's. They will port out to a Felpro 1205 and with bowl work, 2.02's and 1.60's with minor chamber smoothing, they make good street heads with 85 octane gas. 882's make good heads as well with limited porting but they are thinner and will crack if you run lean or overheat the engine.

Great vid. Now i have a idea of how good my ported 882's flow. I figured about 200cfm. now i know.

Great data on the OEM low compression heads. If you must run factory cast iron heads, the best are the Vortec heads, if rules allow. The number is 062, but don't throw a 906 head away, they are very similar.

Thanks for the info on these heads been wondering how they flow for some time, your work is helpful for us low budget guys. Putting a 218 224 comp cam on 400 with 9.7 compression, trying for good torque. Thanks again

Good old 882 love them for what they are ..good video's

Thanks, Eric. You saved me from wasting time on a planned head swap. I was just getting ready today to swap a pair of 487s to some Speedmaster/Pro Comps. The cam is only 480 lift. So, as you stated, there is no gain. Also, the engine the Speedmaster heads were on are now getting some Brodix T1 heads, thanks to your videos. Your videos are very helpful. Keep up the good work.

Thank you for this, I'm getting ready to build an IMCA Sport mod, this is very informative. There is also a Dart head that's approved for IMCA Sport mod.

Those 487X heads were supposed to be good open chamber sbc heads. I had some 041X and 461X closed chamber heads back in the day, both had bigger runners than the versions without the X.

🎉🎉EVERY TIME YOU AJUSTED UNDER HOOD, I COULD HEAR THE DIFFERENCE BIG TIME. 😮 THUMBS UP AND GOD BLESS ALL 🎉🎉

993 head would have been nice for comparison.

Great information! It would be interesting to see what the 60 grit polish does for the stock heads. Any chance you might do a video on the 801, 416, and 601 castings?

I use to run 882 on my 355 in hot stock class they sucked but did the job for the time

487X are commonly foundon 71 and 72 LT-1 Corvettes and Z28 Camaros, they will have guide plates and screw in studs with 2.02/1.60 valves and the combustion chamber relief cut for the 2.02. The 996 heads could be found on the 73 and later L-82 High Performance motors with the same valves and screw in studs/guide plates.

The myth of the 2.02/1.60 stock 882 heads is true. I had a pair that came off a 77 Corvette L-82, open chamber 882s with factory screw in studs & guide plates with 2.021.60 valves. They do exist, but ive only seen 2 pair in my 40yrs of messing with this shit.

Right on

When looking at a small or big chevy heads, it looks like the "closed chamber" heads have a quench pad on both sides of the chamber and "open chamber" heads do not have quench pads on the spark plug side. We used to refer to Pontiac heads as either "Large" or "Small" chambers and we have a 1974 SHP Z28 350 that has 882 heads with screw in studs, guide plates and 2.02/1.6 valves. Keep rolling......

Great video. Those 882s are almost in Camel Hump head territory (recalling your recent video on the 461 heads) Cant wait for the dyno competition between these heads

Some of the old timers use to say to just work on the exhaust side. Get it to flowing above 75% of what the intake flows.

882 I'd rather start with the 1.84 do the 194 valve job myself, tulip should work Looks like biq quench pad so why characterize as open chamber I call them wedge heads pinned studs- those were the days, oil 441 I used the spiral grooved k lines and also to convert to 5/16 I Sunnen od hone the valves 487 best to mill that ex corrosion rather than Devcon X would be nice to see with good valve jobs EQ were great all their parts How about a video on chamber designs, an overlooked place for improvement I asked about the B1 when you said there was room for improvement ( or something like that) cheers

Cool. They all suck for compression and air flow.! Lol. So blessed these days with aftermarket heads!

Thank you Erik for the efforts to compare these GM factory heads! It was very interesting comparison, esp the 487, 487x and the chinese aluminum ones! I've currently the 487s in my '71's sbc, most likely with stock factory cam. Would you recommend upgrading the rocker ratio to 1,6 or rather swapping the cam to bring the better out of the old sbc? I wonder could you ever possibly flow and review the GM's 113s (aluminum) as they are also recommended a basic upgrade on stock sbc? Thank you very much for today's video!

"Ol hydraulic flat tappet because your saving a buck, or used to" 🤣

We used to basically run any head, slightly port it, and valve springs, as long ss it is not a truck head!!

The quench side of that aluminum head looks like it severely shrouds the valves.

I helped a friend with a sprint car in the 1980's. At first he was using iron heads and the car ran HOT no matter what we did. When he put on the first set of Brodix aluminum heads the water temp issues went away forever. He never went back to iron heads again. Do you think in an average street strip application an aluminum head on average could run more spark advance and get more HP due to less hot spots in the combustion chamber ?? of course here we are discussing open chamber which typically means low compression.

That X head was probably from a Corvette. They had X blocks too. Also the LS has identification bumps along the valve cover perimeter on exhaust side. 243 has different bumps from 317 and on .

I like watching your videos and your knowledge my question is why don't you make DVDs and templates for someone who wants to learn how to do their own head porting like on the vortecs or the older double jumps or the best big block factory heads like the 781s or 049 you could also make money I'm sure their are alot of people that would buy them I know I would keep up the good work sir I love how you go into details on what to do or what not to do

Great video. Have you done a video on the 416 heads that so many folks say are junk boat anchors. And that if you put them on a 350 it will be lucky to turn up past 4500 rpms.

That's a pretty cool comparison

They flow about the same as Mexico vortec heads but not at the lower lift numbers like vortecs do! Chambers suck but it is what it is!

I think the people that say they are not open chamber should think of these heads as large chamber. They are probably 76cc chambers where the small chamber sbc heads of the 60's and early 70's would have been 64 cc. Those small chamber 64cc heads will give astronomical compression and they show up in the high horsepower factory small blocks that required high octane fuel.

I have 993 heads they say there like 441 but flow alittle better. I ported them a few years ago before I found your channel. I was on subs aand fish so I used water flow knowledge to port them. some day I would like to send them to you and check them out.

Would love to see the flow number for 191 and 193 heads as well (post-87 with the canted center intake bolts found on TBI cars/trucks.)

oh no . . . . YESH!!!

1.72 /1.50 882 heads were common too

Have you ever done Canfield 220 65 cc chamber heads? I have them on my 406 sbc I think they work great but I’ve had them a long time Your thoughts?? Should I upgrade to new heads I bracket race

Hey Eric, how do these compare to the double humps? I bet tge double humps with 1.94 valves flow about the same with just a little better chamber.

What year heads? I am required to use 416 heads by NHRA.

That 487X seems like it would be alot better with only a slight bit of porting, especially on the exhaust, and the intake bowls,

Have you got any flow numbers for the stock 041X heads?

the procomp head struggles below .300 lift BUT we make better valve cuts to achieve better low lift numbers on these heads! on both the seat and back cut on valve. Besides, this is 2024 and no one runs .400 lift cam! not a single customer has ever requested such a low lift cam, other than old magazine builders that don't know any different or some budget roundy round class racer. Most every cam and head combo i do for customers starts off with .400 lobe, HYD roller. Bang for the buck you cant beat the ChInEeS hEaDs. Yeah they need some attention to be better, guids & valve job but what head doesn't?? (dont say dart, brodix, RHS that cost 2x the price)

Have you had a chance to test the Summit/Dart 165’s with 2.02/1.60’s?

Spier race heads talked pretty good about you

Having had a little to do with these gunkers, and Chev heads in general the cut below the intake is factory. AFAIK all at least earlier GM heads had a similar cut. Depending on the casting depends how much. I can remember scrapping these heads as they had no value. These days however they do,, more so with part number junkies on restored cars Fuellies too were done like that. Factory retainers and collets IF in good order will be ok on a Fuellie with low 500 lift. Oil shields fall off on std engines, that I have seen on Chevs and Holden 6 and V8. Any more lift go good aftermarket. Not ProComp,, I saw one of those retainers broken as the collets tried to pull through. Rotators on any remotely performance engine wil fail and cause dropped valves. Not just GM used them on smog engines, a patch to try and make the engines live to outside warranty. Use 5000rpm regularly and they will cause an issue. Those D shape chambers are useless, and they get detonation on standard engines.

Eric, I’m curious, what is your attitude toward doing work on truly awful heads? I’m not speaking about ones which others have ruined, but those that came bad from the factory and remain untouched, and where the rules pretty much only limit bore size.

The L82 Vette engine is the only open chamber head I've seen a 202 valve in from the factory.

All they're good for is to hold your barn door open!

Interesting stuff,how does stock Chevy heads flow compared to other car makers stock heads? What does Ford & Mopar got to beat the Chevy guys? That would be quite interesting to see also,and IF You would do that throw in a AMC stock head also,I've heard the AMC ****502-* heads from 1974 should be a pretty good flowing head "for what it is..."

Second head from the left has a toasty exhaust valve.

All 76 cc chamber heads have raise seats. the 69 cc heads don't. So, looks like all those from what I see have had 1 really heavy seat job or 2.

Have you ever flowed any 186 casting heads how good can they flow

For ever the “Rumor” was the 487X heads we’re supposed to have slightly bigger runners. 🙃

882 castings with 2.02 & 1.600 came on 79 L-82 vette engines . Dont know about any other cars .

Aby idea what they were originally used on? What vehicle, vett, Malibu, camaro, caprice, 1/2 ton truck,

so the speedway boy running boat rusted heads haha

I be seen 1.94/1.6 especially in a 441

There probably isn't 10 horsepower between all of this heads including the 882 that everyone says is junk. They all suck, but they all got the job done. I've rode in several cars with 882 turds that screamed.

The small valve 882 heads had 1.5 exhaust and a 1.72 intake. The 1.84 intake valve was a 305 thing. The early 305 used the 1.72. The later 305 heads had 58 cc chambers and with .480 lift cam would really wake up a dish piston 350 for not much money. A flat top piston 350 would break the ring lands out of the pistons in short order with the 305 head.

Might flow 190 maybe idk if that close but they don't flow really good

I just got some amazon sbc heads and after watching your videos im questioning if theyre worth it. The bowl arond the seat is bigger than the seat and the bowl cut just scratches the casting slag. So i dont think they will flow good even if i cleaned them up. Also they are afr copys so the guides seem thin since they are bored to 11/32. I dont know if thats good or not.

Keith isn't an older guy is he, like in his 60s? Maybe he had a 68 Camaro? Just a shot in the dark.

Have you ever or will you ever do anything with the world sportsman 2.

Wow. So ? What did the camel heads do? This is the one I always heard about. I don’t know anything about these you have shown.Also the mighty vortex.

your wrong about how the valve stem oring works. it seals the oil from running past the valve retainer if properly installed.

Ok, forgive my ignorance. I've had this discussion about ford heads before & it's was confusing to me that their was confusion about ,to me, what was obvious! And I see the same here, in the chevy circle. What is your definition of a "open chamber" head? Becouse I see the title, "open chamber" tests!!! And yet I see a thumbnail of a pic of 4 closed chamber heads? Why? How? What is your definition? Ford heads we say open if it's "open"!! No quench pad or a quench pad not on a level with the deck!

Just so you know, there is no such thing as a "open chamber" sbc cylinder head. An open chamber does NOT have a quench pad and those clearly do.

Coking

My 441 headed Superstock ran 9.69 at 3000 lbs with that ugly chamber.... Mmmm