BIG HORSEPOWER GAINS with Small Block Chevy Vortec Cylinder Heads!

In this video Robert shows you how he and Joe rebuilt a set of 906 Small Block Chevy Vortec Cylinder Heads!

[@PatandDoopypoopy]

I'm a retired engine Machinist. I would like to compliment you on having these heads hand built. I used to have to do a lot of repairs when people would take new heads right out of the box, put them on their cars and then have problems. Not so much the average mellow Street hot rod, with say maybe 350 to 400 horsepower. It was the race car guys if they were running alcohol for fuel, if guys were running nitrous, any type of endurance racing such as oval track racing. The valve seat width, the valve guide clearance, the type of valve seals used, and of course Spring pressure and valve material are critical when you get into power adders, anything that creates combustion temperature such as prolonged engine load like Circle Track Racing causes. So specially for the guys on a budget, it is hard when something breaks. I think when we are on a budget it is even more critical to be vigilant and have a smart plan. Have a local machine shop at least have a conversation with you over what you intend to do and then usually they will show Mercy regarding price for at least an inspection and measuring critical clearances. Just some random thoughts and opinions. On a different note I hope all of you have Health and Wellness for 2023 and keep on building cool stuff in whatever form you do it.

[@BoneyardRevivals]

Thank you so much for your comment, wisdom and well wishes!

[@skylinefever]

This is often why I see guys buy a bare aftermarket head, buy valvetrain parts from reputable companies, then pay the machinist to redo all the machining.

[@PatandDoopypoopy]

@@skylinefever exactly. I'm glad you said such a thing. The biggest thing I would encounter shop was valve spring pressure and material and quality. Mystery valve springs have hurt a lot of blue-collar hot-rodders on a budget. Valve guide clearance, some people used to stick a valve and wow that would cause a lot of damage eventually if they had stock type Pistons. I could go on and on but I wont. All of you hot-rodders out there I wish you the best. Please just have a plan built around common sense

[@drchevyphdeez7253]

Tip- put ear plugs in the accessory holes so not to paint threads. Had an electrical grounding problem one time due to painted bolt holes

[@BoneyardRevivals]

Solid tip! Thank you!

[@blownaway4371]

Just FIY, Pisscutter Performance here on Y/T did a lot of good videos on the Vortec heads. BIG gains by opening up the exhaust to 1.6!!

[@mediumjumbo7484]

Lots of good Vortec 350 head info on his channel !

[@shootermcgavin2819]

You put a lot of detail into those heads. Well done

[@frigglebiscuit7484]

i bought a 5.7 vortec out of a 2002 cheyenne 2500 truck. but havent taken it out yet. hopefully the 906s arent cracked like that. if they are, im shit out of luck, as the "machine shop" in my town doesnt even turn cranks anymore.

[@cecilsabourin9462]

No apologies needed,you,ve done a great job ,good photos and explanation ,helps me a bunch.Thanks .

[@larryburns4605]

Good job nice see O.E. stuff being built .

[@justinetherton4107]

Well Done! Some good quality budget friendly roller rocker arms in the future is all those cylinder heads need. Thanks for sharing!!

[@KooshdaakaaGarage]

Excellent work! 🍻

[@Tnclweldfab]

How cool is to work so close with the machinist.

[@tonydowns9424]

Great post!

[@jjmccloud]

Great video on these heads! Very nicely done 👌 Another cheap upgrade is the blue or yellow LS springs but I believe you done the best version of a killer budget set of heads

[@BoneyardRevivals]

We actually talked about putting LS valves in these heads but decided not to because we also would’ve had to put different valves in it which would’ve cost more so that’s why we didn’t use them.

[@oscarpuente2029]

👍 outstanding.

[@jasonrogers9169]

Thing I have discovered about the 5.7 vortec back in the day when we machined engines that 80 percent of the rebuilds were not head related though 80 percent had cracks in the heads 🤔. Customers would freak out when they were told you have cracked heads. The unusual thing was where they were cracking. We were convinced that if not for the tear down they would never had known and could have drove many more miles before if any problems would arise. It really seemed like a waste of a really good head that wasn't cracked in the combustion chamber. So we did some extensive trying to figure this out studying. Yes it requires at least 6 years of college to do this. We found in our figuring stuff out that torque plating helps tremendously. Thin casting from the factory and torque sequence puts a twist on the head adding slight pressure to its weaker points. Heat expansion and contracting causing the weaker points to crack in various different places because of the already slight pressure from torque sequence. We all know manufacturers are trying to get the most the fastest so they aren't built exactly square when they are pushing them out the door and usually takes several years before problems start to get their attention. That being said the 5.7 vortec head didn't have an extensive run before ultimately converting to the spread head as we call them. I totally agree on the aluminum head just the 5.7 vortec's didn't have a lot of intake options on f.i. conversions and basically simple carb conversions but you can get a carb conversion plus a tbi to carb adapter to convert your older tbi 5.7 way cheaper then just buying a tbi to vortec intake and locate a 454 tb with 2 inch ports and an inline fuel regulator to bump up pressure and some long tube headers sorry I'm veering off course here. So yeah torque plating is key. The flatter you can bolt them with less stress will do wonders and the potential of the heads are right up there with your more expensive aluminum except the weight and great job on repairing them as it would be a waste to see them as trot line weights.

[@BoneyardRevivals]

Thank you for sharing, that’s a lot of info!

[@danman6969]

I’m with ya I bought a set of 062 vortecs from a kid who needed money, they’re perfectly fine I’m going to have them machined and basically do what you did. Gonna put a nice bump stick in my 90 k5 and need some decent heads to support it. Great video my friend!

[@marvmccready4765]

The "062" Casting is the Same as the "906" ! Poured Hundreds of Thousands if not Millions of them in my 30+ years in the General Motors Corporation Casting Division. The "062" is a Slightly revised version of the "906" if I remember correctly it was in the water passages to strengthen the area that tends to crack in essence a smaller Water Jacket Core was used all other Cores where the Same with Alternative Casting Numbers they all come from the same Tooling and Mold Cast Line. Namely Line #3 or Line #4 and later Dated Castings Line #5 If Cast @ GM Central Foundry Division (CFD) / Powertrain (DMC) Defiance Ohio. They were also Cast in Smaller Numbers at The General Motors Saginaw Casting Division before the Phase over to Aluminum production at All General Motors Facilities. GM No American Automotive Manufacturing Company Cast Iron all of them Outsourced iron around 2018.

[@harleysgarage327]

Great video, I have a set in the garage that need similar treatment.

[@jameshendrickson8159]

I had to replace my vortec heads, but arvid at ACH in Oakland ca stuffed 202s and bigger exh. studded and machine work to take up to .565 lift cam. They are working slick in my whip.

[@trickyshot2002]

I would have taped off the areas that the headers bolt to and the intake connection area before painting them, but I loved the video and love the hands on rebuild of these heads!!!!

[@BoneyardRevivals]

Hind sight being 20/20 I would have too. 🤣

[@pmd7771969]

Good heads if you start with good ones.

[@dannyoutlaw8001]

When you blend the bowls you should always teardrop the guide boss also it really helps especially at mid and upper rpm

[@nunyadambusiness6506]

Hey watching your video I noticed the. Casting markings on your 906 cylinder head and I can give you some insight on these as well as many castings That where cast at the General Motors Product Casting Division in Defiance Ohio as what I was able to see I was involved in the Making and Casting of the heads that you Provided this Content from. Also the repair is a proper way to remediate the cracking as it isn't a good idea to weld on a 906 casting or a casting from the Defiance Ohio Foundry. As the casting are of as Harder metallurgy than the Saginaw Casting Division of General Motors. Your Port work is also proper as per the 906 VORTEC port is The Best Flowing from a Engineering position as it uses much of the pre engineering testing for the Gen III Small Block that Follows. I did also enjoy the video and Content. Thanks

[@patrickwendling6759]

Thank you for your knowledge and videos USA 🇺🇸 USA 🇺🇸 USA 🇺🇸 🙏 🙏 🙏

[@scotts439]

The vibratory tumbler used to clean your rocker arms at 13:40 works awesome!!!

[@BoneyardRevivals]

They had to be in there for several hours, but yes it did work well

[@scotts439]

@@BoneyardRevivals i sold him that machine!!!

[@BoneyardRevivals]

@@scotts439 well thank you! Cause that made my life way easier! 🤣

[@scotts439]

@@BoneyardRevivals you are lucky to have Joe nearby... That guy is the best!

[@jameshendrickson8159]

Oh, i also went with a retrofit hydraulic roller cam and a geardrive timing gear setup, a combo im not going to get away from on my future gm small blocks or mk4 bigblocks..

[@chriscatarcio2983]

Budget don't mean half assed. You did them correctly. Unlike some outher budget build hacks that think a valve job is done with valve grinding compound. L.O.L.

[@ronnabell7357]

11¹¹😊😊

[@inscoredbz]

I agree with everything you said except about the afr enforcer heads. They use the same valves and valve train as their hi dollar heads. They probably would need a valve job, but that's about it. I bought a set bar and put good stuff in them and a valve job, guides checked and decks milled if needed. Everything was spot on except the valve job and it was within tolerance. For a 350, your vortec heads are a better choice to begin with.

[@BoneyardRevivals]

Only other thing I would say is what about the guide clearances? In the future I want to do a build on a bare casting and look at all of those things. And I wasn’t necessarily calling out just the AFRs. They are arguably the best out of all of the aftermarket heads but they are just the ones that I mentioned.

[@inscoredbz]

@@BoneyardRevivals my guides measured fine, I made sure he checked them, I didn't buy the AFR enforcers, I bought the no brand name just like them and built them. Exact same heads, just with stock sbc valve stem diameter. I built these before afr offered them. With a valve job, comp cams valve train, and back cut pbm severe duty valves, I still only had around $800 in them (pre cooties 19 prices). I wouldn't waist my time with procomp/speedmaster heads. They're junk and don't make power. any aftermarket heads you buy will need a valve job. They all suck. They just pump them out as fast as possible.

[@MauriceLively-in4nn]

What's the name and location of your machine shop? Awesome video!

[@williamaddair5873]

Hey got some 906 vortech heads that need repairs were and who was your machine shop guy was impressed buy how he fixed yours

[@davidreed6070]

I would have had to thin down the guide bosses on those heads and they work well

[@fppro1679]

I heard these stock vortech heads have a problem with cracking.

[@lylejohnston4125]

While you're on vortec heads, I have a question. On my '98 Silverado and another truck, too, the #4 cylinder exhaust valve spring became weak and at higher rpms, (in drive at 70 mph) it developed a miss. when it came back down in OD, the miss would go away. My #4 exhaust spring was .040" short. The other truck actually had a broken spring. Is there a reason #4 cylinder ex. valve would have a problem. Is there a hot spot there? I noticed the crack was in the center of the head. I fixed mine with a used spring 3 years ago but, it missed again and #4 code came up again. I haven't had time to check it out, yet.

[@johnschuster9192]

Thats a real catchy video you fellas made! I was laughing at the intro!Will you be doing any chevy big block heads from older castings..I have a 396 with not so great heads..Can you help?And many thanks for your time.

[@BoneyardRevivals]

We have a 70s 454 that will eventually get built and that will probably have the heads rebuilt but we do not have a time stamp on when that will be yet.

[@ritchschut1997]

Sticking with your budget theme, You REALLY should have taken the time while bowl blending to gasket match the ports ( intake and exhaust ), and unshroud the valves. You already had the die grinder out. Doing these couple of things would have added MAYBE an additional hour per head to do. The gains made by unshrouding the valves would have far outweighed the little bit of compression lost.

[@BoneyardRevivals]

We did actually gasket match the intake to the heads when we built the engine.

[@8luggarage]

Do you know roughly what the power gain might be with aftermarket aluminum heads vs the vortec heads?

[@BoneyardRevivals]

With out knowing your desired engine build or the heads that you’d be comparing to them, it’s hard to answer. Overall cylinder head casting makes a difference. Valve size, cc runner and chamber volume play a big role too. Those types of attributes make all the difference. Aluminum heads are probably the way to go for a 400 plus build. But for the best of the cast stock go heads the Vortecs are the way to go.

[@daveunbranded]

Probably will not be answered because of age. What is the deal with older L98 aluminum heads?

[@darrinstone49]

Where did you get the brass valve guide sleeves & for the crack?

[@BoneyardRevivals]

The machine shop provided them, so I am not entirely sure

[@williamherron9365]

Should have worked the chambers too! Unshrouding the valves is another place to find power in the vortec heads. Could have also lifted the roof of the exhaust ports into a gasket match. Those two areas and the bowl blend are their prime spots to make flow. Have a pair done like this on a stock cammed carbed vortec 350 in my 2000 s10 with a 2500 stall and 4.10 gearsand she rolls out strong for a ~.410 lift motor. Planning on 1.6 rockers to take me up into the .450 lift range where the heads breathe best.

[@BoneyardRevivals]

We talked about doing the chambers too but I wanted to save some cash as a bowl blend and chamber blend would’ve cost a bit more. I also feel that the common guy would just be looking to slap a set together. We figured that between the mill job and the bowl bend was good for a potential gain of 40-50 horsepower.

[@kevinseybert5795]

If your first time machining good job but with new heads out there cheeper already prepared I would of gone new and not worry about the crack in the head causing problems down the line

[@rogerbritt1964]

Afr enforcer heads use the SAME HIGH QUALITY ARGENTINA 8MM VALVES AND PAC SPRINGS AND BEAD LOCK KEEPERS as their race heads -- they are not garbage

[@BoneyardRevivals]

Okay I hear you, but what are the guide clearances and the concentricity of the valve job? They bang that out in a factory and as long as it is in an “industry” spec, and off they go. Having an affordable head with good valves and springs is cool, yet completely worthless is it wipes out a guide or a valve seat due to the poor quality control You get much better quality from a machine shop who takes the time to check those crucial parts. There is a reason why a complete set of heads is cheaper than having a machine shop Professionally build you a set. I’ve know guys who have bought complete aftermarket aluminum heads and they came apart because of those issues. Imagine being that poor dude that spends a bunch of money on a complete set of heads for their motor that probably also a bunch of money wrapped up in it just for something to go wrong because of the lack of quality. And of corse that isn’t going to happen to every set of heads you buy, but in my opinion I’d rather put my money into something that I know is good rather than play cylinder head Russian Roulette. That’s why you’ll never see complete set of aluminum heads bought and slapped on an engine on this channel because there will probably already be a hole lot of money wrapped up in that motor build and I will not risk something so small yet so important and have it go wrong and ruin an entire motor. I am not just knocking AFR I am talking about all complete aftermarket aluminum heads that are slapped together in a factory. I actually like the AFRs and would like to do a build on a set of enforcers but select the parts and have a professional job done on them, so then we’d have the best of both worlds.

[@chrisreynolds6520]

I bought the chinese castings bare, same ones as the Enforcers. Bought good parts and drove them to Lloyd Elliot. Got back a set of heads with good parts in them, cheaper than buying the Enforcers. With Lloyds port work they also flow 300 cfm @ 0.600. 11:1 383 I built made 502 hp @ 5,600 and 520 tq @ 3,700 with a 218/228 @ 0.050 roller cam on a 108 LSA, 106 ICL and 0.578" lift. Great budget torque monster for my 7,000 lbs 1997 Express 3500 conversion van.

[@cocobolo1911]

How about a video on L98 aluminum 113 heads? Doesn't seem like anyone has gone over the old Corvette heads.

[@BoneyardRevivals]

I’d love to do it! If a decent pair fall into my lap I’d definitely do it!

[@ChrisMcCutcheon-wj2pp]

292 and 492, not Crack prone and sum 292 casting head was 200 cfm on intake, best sbc heads ever

[@jacobjarvis2545]

What spring and retainers did you use and what was you retainer to guide clearance

[@BoneyardRevivals]

We used .500 lift springs and we reused the stock retainers. I can’t currently recall the the retainer to guide clearance though.

[@frigglebiscuit7484]

just use z28 springs and take he inner damper spring out. make sure your valve seals are hammered down all the way, and youre good to like .500 lift, with stock retainers, locks, etc. just a spring change.

[@johncalhoun8011]

Man! I would Love for you to build a Set of Heads for my OBS Chevy Truck. I have a 1991 Short Bed. How do find out if I have a Vortec Engine in my Truck

[@BoneyardRevivals]

You can look on the back of the block on top of where the bell housing of the trans meets the block on the driver side there should be a set of 8 numbers casted into the block. (If it’s dirty you might have to clean the grease and etc off to read it. After you get the numbers you can look up a list of SBC casting numbers online (I recommend outintheshop.com) and you can look down the list until you find your casting number. With the truck being a 91 I’d guess it’s not a Vortec engine unless someone swapped one in. The casting number for the Vortec Cylinder Heads you want to look for are 906s and 062s

[@johncalhoun8011]

@@BoneyardRevivals I'm thinking it may be a TBI Engine. Because it's Fuel Injection

[@eliwagner4360]

That's a lot of work for a cracked head. I'm thinking cheap aluminum heads are the way to go for most people.

[@BoneyardRevivals]

That is a fair point. But I do love saving rusty junk!

[@shitbox82]

The AFR enforcers might be Chinese castings, but I guarantee the parts and machine work are just as good if not better than what went into your vortec heads.

[@BoneyardRevivals]

I disagree when it comes to buying the head completely assembled. Most specifically with the guide clearances and valve job. I have meet guys that have had a set of completely assembled heads from a factory and they wiped out a valve or a guide. The AFRs enforcers are really good head but when it comes to their guide clearances and how they cut the valve job in the factory I’d rather rebuild a set of cast heads or have a good machine shop assemble a bare casting and check those clearances and concentricity. The factories don’t take as much time to go over those clearances and the valve concentricity, it’s more of a quick check of if they are at least in a certain spec. As a good machine shop will take the time to make sure that it is well with in spec rather than just a quick (yea this looks good enough) I do like the CNC ported intake runners and think as a bare casting you cannot beat the AFR enforcer. But I would much rather hand select my springs, retainers, and valves and build the heads through a machine shop. Then I would argue that the AFR Enforcers would be one of the best street/ mild strip heads you could buy. I would actually like to eventually do a video of buying a bare casting of the AFRs and do a full build on them and actually show the guide clearances and the concentricity of the valve job.

[@shitbox82]

@@BoneyardRevivals Wow I didn’t know AFR’s quality control is so bad, I know many people that own AFR heads, myself included, and have never ran into the issues you speak of. I’m not saying those issues aren’t impossible, but I certainly wouldn’t condemn all name brand cylinder head manufacturers over a couple bad experiences.

[@BoneyardRevivals]

Oh I completely agree but either way these heads might be on a motor for 20 years but the car only gets a few thousand miles on it and the guides are done. It’s sad some of the quality of stuff that gets out to the public. I’ve recently just saw 2 brand new Weiand intakes that were ordered for engines at our family friends machine shop. One for a small block Chevy and one for a big block Chevy and the bbc one was actually casted in the USA and both castings were messed up and actually had to be milled to actually fit correctly.

[@chriscatarcio2983]

Do the research. Don't trust out of the box heads from ANYONE.

[@aidenstefanson2175]

Some parts like valves and springs might be just as good, but the seats are extremely soft, and the aluminum is quite soft. Every experienced porter will confirm the aluminum cuts like butter. The valve job is inconsistent, just like every factory assembled head, regardless of where it's put together. I second the notion you should never open a box and bolt on.

[@johnjon6349]

I cringed a bit when I saw you buzzing the bowl job - those heads flow as good as they do for a reason. Part of that reason is the air flow dynamics created by the bowl Venturi area…. Just grinding it out to make the area bigger isn’t necessarily going to make it flow more air. The Venturi effect is what makes or breaks flow around a valve.

[@skylinefever]

Interesting. Usually when someone finds a crack in common head casting, they throw that casting out and find a better core. People still rebuild iron heads on a budget. The stuff you can buy at most parts stores is pathetic. Getting a head rebuilt at a reputable local machinist is way better.

[@paulpoindexter4050]

I think you meant 7/16 stud...3/8 is stock

[@claytonbryant20]

Hey I'm thinking about putting some new vortec head on my 350 TBI will it hurt the bottom of my engine in the long run

[@BoneyardRevivals]

I don’t see how it would long as you use the right valve train like your push rods and rockers and your lifters if you put a new cam in.

[@claytonbryant20]

I'm going with some 1.5 roller rockers

[@BoneyardRevivals]

They should work long as the are the self aligning ones. So a stock set of a pair of Vortec heads would work, that’s what we did here with these heads.

[@skylinefever]

Don't you also need a special intake manifold, higher flow injectors, and reprogrammed ECU to make the Vortec heads function? Anyway, I don't see how the Vortec heads could be harmful to the TBI bottom end. Some people buy TBI cores for their SBC build because they are plentiful and cheap. Also, even though they had flat lifter cams, most would let people use an OEM roller lifter spider and OE replacement roller lifters to save money.

[@BoneyardRevivals]

That all depends on if you plan on keeping it fuel injected. The only thing you need that I forgot to mention the the carb conversion is that special intake since they changed the angle of the bolts and the amount on the Vortec heads. We have a full engine build video showing and discussing these heads on what was originally a TBI 350 and every you need to make the Vortec heads work.

[@looneylonzo28]

this is the life of poor people. We’ve been doing this all our lives we don’t buy it we build it my only group if you should not of painted your intake surface. I would’ve put the largest valves that I could’ve. assuming you had the clearance piston to valve

[@BoneyardRevivals]

Hindsight being 20/20 I won’t have painted them. We did think about going with a 2.02 and 1.95 exhaust valves and ls springs but we wanted to same some money, so that’s why we put this together with stock valves and slightly upgraded springs.

[@peggyparrow2059]

Im

[@gila-clifffirewood5796]

You actually just said "actually" about 997 times

[@BoneyardRevivals]

Are you actually sure about that? I am actually sure it was like actually 998ish, but I actually could be wrong.

[@pmd7771969]

He just opened the valvestem clearence too far.

[@jimthomas1989]

Bonehead Revivals , If you are after horse power gains , You used the wrong head gaskets ! And that cracked head is Trash . Iron is like glass , it cracks. Something caused the cracks and you didn't fix that Something .

[@BoneyardRevivals]

Dear random internet key board warrior that thinks they are better than everyone else, Thank you so much for your comment and we are so glad you enjoyed the video! P.S. If these heads are trash, at least they have something in common with your attitude. Thank you and I hope you have a fantastic rest of your day. 😁

[@jimthomas1989]

@@BoneyardRevivals , I am not a key board warrior , I have rebuilt more small block Chevy engines than your entire family has fingers and toes , And if you need a set of good Vortec heads off a 96 small block 4 bolt main 350 , I have a set . And the Part Number for those Felpro head gaskets is Felpro 7733SH-1 AND ! I was porting heads before you were born

[@jimthomas1989]

@@BoneyardRevivals , And YOU said it best at the 1:49 minute mark , You are a GOOF 🤪 YOU just forgot to finish it : Goofy Goofball Goof 🤪

[@frigglebiscuit7484]

i can tell you what caused the cracks, and it wasnt overheating. some goober over tightened the piss out of that head and cracked it.

[@claytonfoster9146]

Anyone gonna say anything about painting the gasket surfaces?

[@pmd7771969]

Ruined head. Can't be fixed.

[@BoneyardRevivals]

Explain to me why they are on a running 355 then? 🤔

[@frigglebiscuit7484]

false. pinning works 100% of the time.