882 vs. 993. Calling sbc experts.

What we have is a $100 400ci small block in our challenge car. The heads are casting 882. 76cc 1.94/1.50. Best I can find is a fairly consistent >200cfm rating

in the garage is a well used 350 wearing some heads with casting 993. Not 100% on valve size since the 993 casting was available with either 2.02 or 1.94. I found a couple instances of people saying these flow 205cfm. 
 

anyway. I've scoured the usual forums with everyone claiming they got their Chevelle's to run 12.50 with 350hp and they all pretty much claim that while both castings are garbage, the 993 is worlds better. 

I know I'd have to drill the steam holes in the 993 heads but that's nbd. I'm more concerned with the budget hit since while these are both used truck heads one is very likely an upgrade and so not really like-for-like. 
 
What does the hive think?

I know the the 882s are smog era performance heads found on L82 Vettes and Camaros.  Common upgrades are threading them to convert to bolt in rocker studs to runbetter springs and cams.  There are a few Hot Rod and Var Craft articles on the internet about these heads.  My L82 Vette was slow but torquey and was way faster than an L48 Vette.  

I recently ported a set of 882's - the intakes are pretty nasty in the bowl.

Have you been through here? http://nastyz28.com/threads/993-heads.37332/

I’ve also ported a set of 882’s.  Some are lightweight castings.  Some are not.  Mine were not.  I think they get a bad rap due to the fact that some are lightweight and people think they’re all that way.  Mine came from a ‘76 L-48 Corvette.  The one with all of 180 or so hp.  We’ll see what it does with my port job.  I just don’t have anything to put the engine in right now.  Might throw it in the CJ.

Magnaflux & vacuum test them before worrying about which ones to mess with, that may make your decision for you. The 882's are more likely to have cracks from my experience in machine shops. I've been building a set of 993's for a 357 going in my 81 Malibu eventually. Screw in studs, replaced all the exhaust seats, big valves, ported, unshroud valves, etc.

Thanks for the replies. I had read that thread from nastyz28. Some conflicting info there. And I've read elsewhere that both casting numbers had variations over the years. Maybe the only sure way to know would be to pull both sets and take a good look. 
 

I know it's silly, but I hesitate to have these heads checked for cracks because I don't have the budget to replace them with anything other than the known good 993s on the other engine. That might not be the worst thing but it sits a little sour with me. Like if there's a problem I'd rather not know. It's irrational but that's where my head is at. 

Unless there is a significant raving of one head over the other, just run the known good ones. I'm pretty sure one head is not going to be worth 50hp over the other.

If you're going to pay money for heads at all (being getting them, magnafluxing them, or machining them), I'd go Vortec, or the EQ Vortec head casting that can fit the old style intake.

Dumb idea... what can you get for them if you sell them?

Because honestly... they both suck hardcore in stock form.  They can be ported with success, but you might be able to call it a wash if you sold them and bought something a bit better.  They are both big chamber smog heads that were well-matched to the 150-190 hp engines they were installed on originally.

882 and 993 heads are so remarkably similar, you can mix and match them and never know the difference.  For that reason, neither one is better.  Certainly not "worlds better" as you heard.  I might take the above suggestions.... magnaflux and see if two of them are non-lightweight castings.  Whatever they are, run them.

If you can sell all four for $300, get a set of magnafluxed Vortec heads (906 or 062) and enjoy 20 more cfm on the intake side with stock 1.94 valves.  You'll also have 65cc chambers to get that 400's dished pistons out of the low 8's compression, a far superior chamber design to take advantage of that compression bump, and way more mid-lift flow.  You can fight with the smogger heads with porting and bigger valves to get more than 300 hp, or use Vortecs and stab a cam in to make a dirty 400 hp.

Of course, you'll have to get an intake to go with it, but sell the intake you have and hit up a marine junkyard for a Vortec carb intake.  Mercruiser, Volvo, and OMC used a re-pop casting of the carb intake that comes on the ZZ4 Vortec crate engine.  You can usually find them for $50, but they aren't common.

If you have to run what you have, just find the two best heads and bolt them on.

In reply to Curtis73 :

Was kinda hoping you'd impart some knowledge. Thanks. Locally I couldn't sell these heads for more than scrap, and finding decent replacements at one of the local yards will be next to impossible. And no marine yards in the high desert of southern Utah. And if I were to find some decent heads for decent money elsewhere I'm pretty sure shipping would kill any savings. The 350 w/ the 993s was a parts house rebuild about 18 years ago and lived in a 6000lb c30 work truck for probably 100k. That said, the thing was STRONG. I'd be shocked if it was less than 300hp, the way it moved that truck, even with the 4.10 rear. It's our plan b. 
Vortec heads would be my first choice but after 1 year of looking I haven't found a usable set locally for less than $500. And I'd have to factor in a much more expensive manifold. 

I have no reason to think there is anything wrong with this 400. It was in a van that someone had been overhauling with all the pimp interior. When I had the oil pan off I put a mic on a piston skirt and it was 4.155 so I know it has been rebuilt. Also 50 extra inches is nothing to sneer at. 

Correct, 50 extra cubes is great, but it doesn't add power, it adds torque and gives you a lower peak RPM at which that torque appears.  I guarantee that rebuilt 400 did not make more than 200hp unless significant money was spent.  My guess is 170-180 tops.  To get more than 200 hp, it would have needed flat top or dome pistons and more cam than would feel "quick" in a 6000 lb truck.  With the inefficient chambers and the siamesed bores, it would also require 93 octane or it would have detonated itself to smithereens.  

The problem I have with a stock 400 and smogger heads is that it was assembled at 7.8:1 compression (depending on the year and what pistons were used during the rebuild) and it doesn't really have much potential as-is.  Reman pistons (especially overbore pistons) are often manufactured with a higher pin height to reduce piston overall height.  This is done for many reasons; first, to prevent increasing compression with the overbore, to compensate for the possibility of the deck or heads being shaved during a rebuild, and also to compensate for the fact that (if no machining was done) the deck might not be straight.  Better to play it safe than have things whacking into other things. 

Heavy truck + 4.10s + [probably] granny gears + low rpm grunt will seem quick... for a truck, but put that in a camaro and it will be a mismatch unless you spend your money on a 2.43 rear gear swap.  All that torque will mean nothing if you can't get the tires to stick, or if it quickly rises past an RPM where you're making torque.

Tell me more... I might have missed what it's going into.  Weight? Axle ratio? Tire diameter?  Transmission?

My recommendation is to run it as is since it's a challenge car, but you'll have to find ways to make traction happen; gears, slicks, gentle right foot.  If you're just looking to compete and have fun with the other challengers, run what you brung.  If you want to win, my guess is that you'll be spending money somewhere; either bringing the 400 out of the 1970s, or making changes elsewhere to crutch the mismatch.

Cadillac mastered this in the 70s and their 500ci engines.  The recipe is to make crazy torque, pair it with a modest 2.48:1 first gear ratio, then stuff 2.43 gears in the axle.  You felt like you were in a rocket.  Holding your foot to the floor, first gear would take you to 50 mph or more.

In reply to Curtis73 :

It was the reman 350 that felt quick in the c30. With a th400. 
 

we'll be using a Saginaw 4 speed of unknown flavor for the challenge car, with a goal weight of 3000lbs. 9" rear with 3.50 or 2.49 (we have both) gears and 245-45r17s in soft but streetable. Traction will be an issue, for sure. I'll be pretty happy if we can run 14s. I may be wildly optimistic. 

Sounds like a good candidate for setting up an engine the way Buick used to do it.

Big stroke and relatively small valves and ports to keep the charge velocity up. Really good cylinder filling at low rpm, make gobs of torque in trade for less RPM and gear the car accordingly.

It's all over by 4500rpm but it pulls like a freight train.

I was involved in limited class street stocks for about 20 years. We had to run 'smogger' heads and nobody would use an 882. The heads of choice back then were 441, 993, 126 and a few others I can't recall, but absolutely nobody would run an 882 because they were so bad. Except they weren't.

I did a lot of comparison between all the heads, castings, and port shapes and found the 882 was no worse than most, if not all of the popular ones. There was a time when you could get $900 for a clean set of 441's and they were no better than the 882's that you couldn't give away. I have seen stock 882 heads outflow double bump heads which is what all of us would have been running if we were allowed. They're not good heads, but not as bad as their reputation would suggest, and I don't think there would be any advantage to use the 993

Oh, gotcha on the 350/c30.

I think (honestly) at 3000 lbs, either engine (since they're stock) will be about the same speed.  The 400s just got extra cubes.  They often had the same head ports.  The 400s were used in trucks for extra grunt, but they all make 150-190 hp.

Because of the 3.50 gears, that might actually give a tiny edge to the 350 since the torque curve will peak higher than the 400.  That might give a traction benefit to the 350.

I used to have some dyno sim and track sim software, but I don't anymore.  Look up Desktop Dyno.  In their suite of software (some versions free) they have dyno sims and strip sims.  I would see if you can download those and compare the two engines in the same car.

Maybe it's a buyers market or maybe I just got lucky, but I just called my guy at the scrapper and he has a set of vortec heads he'll sell me for less than a manifold will cost. If course that is if they're not cracked. And I'll have to do the steam holes. 

In 1986 my first car, a '77 Monza Spyder, had a smog dog 400.  Tiny little Rochester Dual-Jet carburetor.  We thought it as a stock 305 and couldn't believe how quick it was.  When the engine was pulled, after I wrecked it, it was discovered to have 6 freeze plugs.  That's not a 100 guarantee, but pretty sure bet it's a 400.

So a deal was made and I'm waiting for a call to go get my new heads (whole engine really)

Not sure what will come of the 882s. The 993 motor is a good runner so we'll leave it sealed up for now. 
 

I read an old JP magazine article where they took some old 350, stuck some 062 heads on it, installed a cam w/ roughly .480 lift and 230*@.050 and made 370/370. Engine masters did a budget 350 with 062 heads, .480 lift and 230*@.050 and made 365/380. I  got some 062 heads and I plan to order a cam with .480 lift and 230*@.050. We have 50 more inches. Should be fun. Thanks for all the input everyone. 

My daily rocks a cam with 231°@0.050 and 0.470" lift, but runs 108° lobe separation for some good mid-range grunt, but a nice choppy idle. Running heavily ported 305 heads though, and steel shim head gaskets and flat tops for a calculated 10.9:1 compression. Runs fine on 91 octane, and has done so for about 6 years now.

I think you'll find that the Vortecs will serve you well.  They're better than Bowtie heads by a fair amount.  Some combos pick up 50 hp with a Vortec head swap alone.

I made a good living as a side job for a while building Vortec 350 longblocks.  I was working for a custom/hotrod shop and would assemble them in my spare time.  I guess I built about a dozen.  They were all sold as replacement for street/torque/truck/towing applications.  I stabbed in a Melling 22124 for flat tappet blocks (202/213 duration) and they were 290 hp.  For rollers I used either a 22129 (198/210) for 300hp or a 22131 (207/214) for 325hp.  The 22124 is a Mercruiser grind with a 110 LSA that was amazing for midrange torque and worked equally well with an I/O or in a tow pig.  You could step up one or two ticks for your extra displacement if you do the 400.  Heck, with the extra cubes, the 3000 lbs, and the 3.50 rear, I might push it to something like a 215/225.

The Vortecs offer great extra intake flow, but are still a wee bit light on the exhaust flow.  If you're running them as-is (not ported) I would definitely do a split pattern cam with about 10 more degrees on the exhaust.  Another ticket some people do is to use 1.6:1 rockers on the exhaust if the lift will help.

Stock Vortecs only like about .480" lift at the valve, and that's really all you need, but there are dozens of retainer kits out there that will allow .520" or .550".  They're cheap.  Some guys go all-in and cut down the guides for more lift, but unless they're ported and flow tested to show significantly more flow above .600" lift, it's not necessary.

You can also run about a point higher compression with Vortecs for a given octane.  The old school math for SBC was to multiply your compression by 10 to get octane, but I consistently ran my Vortec boat on 87 with 9.5:1.  If you want to spring for 93 octane, 10.5:1 is a no-brainer.

One more thing I'll add.  Take the time and measure everything.  See if you can get a part number off the pistons to research ccs of the dish.  Use a plunge micrometer to measure the piston deck height.  You should probably also cc the chambers.  Stock, uncut Vortecs should be between 64-67cc.  Get all the math you can and do a proper calculation of compression ratio.  You can plug in different head gasket thicknesses as well to fine tune the compression you want.

THEN choose the cam.  If you go as high as 230 degrees intake duration on 9.0:1, you'll be mismatched.  Same goes for 10:1 and a 215 degree cam.  Too many times I've seen people put the cart before the horse and they end up with a wheezer.  You'll be way faster with a smaller cam to match lower compression than if you go too big with the cam.

If you're lucky, you'll also find a compression ratio that will match up with a cam that will let you keep the stock springs.  I would probably push stock vortec springs to a 215 duration, but you might hit valve float at 5500 rpms.  For challenge money, cam choice that keeps stock springs might save you a couple hundred bucks for that sweet Kirkey seat you've been eyeballing on CL.

Edit:  One other thing if you go with a bigger cam and need springs.  Do your own research on valve springs and don't trust the cam manufacturer.  A company like Comp makes about 6 spring pressures for SBC, so they pair one spring rate with a dozen cams.  Only one of those cams will be an actual match to the springs but its cheaper for them to shoot the middle and just make a small selection of springs.  Find the open/close seat pressures from the cam manufacturer and compare it to the open/close spring rate.  If it isn't really close, find your own springs.

There are really only a few companies that make cam blanks.  Then Comp, Lunati, Crane, etc buy the blanks and do their own grinds.  When you buy the big names like Comp or Lunati, you're paying for the advertising and some true bullE36 M3 marketing.  Any company that makes a "thumpr" cam which is specifically designed to have a choppy idle with no regard to actual torque and power production is not a company that needs my money.  Any of the cam manufacturers know duration, ramp rate, LSA, lift, etc to make a good grind.  That is one of the reasons I do Melling.  They have thousands of grinds and can custom grind anything you want for sometimes half the price of Lunati or Comp.

In reply to Curtis73 :

Thanks for the info. Cam selection always seems to be 1 part theorizing, 1 part following a known recipe, and 3 parts black magic. I love learning this stuff. 
 

One more question then, sir. 
what about this one : https://www.summitracing.com/parts/sum-k00132/make/chevrolet

It is a little long on duration maybe, but given that (I hear) a 400 can't spin too fast with stock rods anyway, and this IS bigger than 350ci, I think I like it. I plan to measure everything when I get the old heads off but I'm quite anxious to start hoarding parts. 
 

And if someone locally was selling a kirkey on cl I'd probably already have it. 

It is a 400 so it wll have more duration tolerance than a 327 or 350. I don't know what it's going in, but if it's lighter or has decent gear, like 3.55 - 4.10 you'll want more cam.

The 230/480 cam that used to be very popular with 400 builds was my go-to grind (I bought the GK c1h-288 but everybody had one) when I was building limited race motors until the lift rules came in. I built and sold a lot of 9-1 motors with that cam. Lighter car/decent gear, it will work well on 9-1 compression and pull like crazy. If the car is either heavy or has lousy gear then you're better off with less duration, but it will sign off early and you won't make a lot of power. There's a lot more to consider in the combination than just compression vs duration.