291 Double Hump HeadsThe two Vortec heads casting numbers are 10239906 or 12558062. This shows that the two-barrel carburetor becomes. Fuelie Cylinder Heads Launched SBC Performance. Chevy cylinder head Identification - Small block casting numbers, Big block cylinder head, camel back heads, double hump heads Find cast numbers Cylinder Head ID Use these casting numbers to identify the heads you have. 60cc CNC-profiled combustion chambers combined with a state of. Cylinder Heads for Small Block Chevrolet ">Trick Flow® DHC™ 175 Cylinder Heads for Small Block Chevrolet. Watch on. These heads are getting rare because they have the accessory mounting holes in them and alot of them have been used up. Plus, the decks and walls are cast extra thick to increase casting strength and provide plenty of material for future porting. We are only interested in these casting. Based on the iconic “double-hump” or “camel-back” (fuelie) cylinder heads of the ‘60s and early ‘70s—including the famed 461 Fuelie heads—the DHC 175 castings are modern aluminum versions with straight spark-plug locations and improved 60cc combustion chambers. Made from premium grade, lightweight A356-T61 aluminum, DHC 175 heads feature the exterior styling and straight spark plug holes that deliver the nostalgic appearance of the original factory performance 186, 291, 461, 462 "double hump" or "camel back" castings that customers want. Steve Reply Save Like bracketchev1221 · #8 · Oct 20, 2009. SBC 291 Double Hump Heads - $300 (Puxico) Ad id: 2611206944400079. I also have a set of 993's off a 72 350. There are a lot of castings to choose from when running the Chevy Double Hump heads. Whats the difference in these heads???. Today in the shop we’re learning about our new aluminum double hump cylinder heads for the small block Chevy V8. 291 heads were used in 67 to 69 on 302, 327 and 350 engines. Heads with tall casting marks were identified as 291-, 461-, 461X- and 462 castings and did not have accessory bolt holes. But when the carb and intake are added the flow numbers are virtually the same. Cores Wanted: ‘186 & ‘492 straight plug “Double Hump” Chevy Small Block heads with accessory holes and ‘291 “Double Hump” heads, which do not have accessory holes. The camel humps originally didn't have screw in guide plates. Actually the 291 and 292 are identical. 291 Double Hump Heads Z28 SS Camaro Chevelle Nova Corvette - $300 (naples) Original date matching set of 67 291 Small Block Chevy Double Hump Heads. But the 291's i have are factory 2. I also did not know there were single hump heads until I bought this car for its engine components. They are still used in a variety of applications. 882 head is a 76cc smogger head, 291 is 64cc closed chamber head. I'm afraid the heads might need alot of work. Get a head with 180cc ports minimum. They likely choose to not install them to make them more like the original heads for the 60s restorere. Even older is the troglodyte-like 64-cc chamber heads, often referred to as “double hump” or “camel hump” heads because of their distinctive casting marks on the ends of the heads. Not saying there is any issues with the. 02 intake valves, and a 400ci 511 block that is allegedly 0. I have a 67 camaro with a large journal 327 bored 30 over with 2 valve relief pistons, stock 291 double hump heads, edelbrock performer intake, holley 650 with vac secondaries, hei with vac advance, comp cams 292h cam, and long tube headers. Small Block Chevy Double Hump Heads. (3927186) Chevrolet Small Block Double Hump Heads. Mostly good for restorers these days. 291 heads are the same as 462's which are essentially the same as 461's. item 5 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7 $700. Here is a set of heads that will make the engine perform as it should sell those hump heads to someone that wants them. Today in the shop we’re learning about our new aluminum double hump cylinder heads for the small block Chevy V8. 00 shipping GM Chevy 3917291 Heads Camaro Corvette Double Hump 1967 1968 In Michigan $800. Shop Cylinder Heads at Summit Racing. Class racers had used up most of them. 3:1 Static Compression Ratio with Flat top Pistons and a. 2850 pound car Aug 11, 2011 #10 T trmnatr Veteran Member Apr 22, 2009 650 Maryland ProStreet383 said: I have to agree on all of the above. 291 Chevy Small Block Double Hump Camelback Fueler CYL Heads 1. Here is a set of heads that will make the engine perform as it should sell those hump heads to someone that wants them. If all out HP is desired, then there are better choices for the 383 than these heads and the camshaft that you have chosen. These heads are getting rare because they have the accessory mounting holes in them and alot of them have been used up. 291 heads vs 461 heads. The Speedway heads come with a spring for flat tappet cams while the Trick Flows are equipped with hydraulic roller springs. 94 valve version was used on the 327/275 as well as the 350/295. Summit Racing™ Cast Iron Cylinder Heads for Small Chevy Summit Racing Part Number: SUM-152123 UPC: 190861096202 Combustion Chamber Volume (cc): 72 Intake Runner Volume (cc): 165cc Cylinder Head Style:. Don't confuse with the 70 over the counter 340292 angle plug. Differences Between 291, 461 and 462 Heads. There are 291, 462 and 461 original double hump heads that GM made -they all have different CC volumes. I run power brakes, have an m21 trans, and an 8. Chevy cylinder head Identification - Small block casting numbers, Big block cylinder head, camel back heads, double hump heads Find cast numbers Cylinder Head ID Use these casting numbers to identify the heads you have. 291's have a boss for the temp sending unit - some are not drilled , most are. My heap had 1964 power pack heads on it, small chamber so healthy CR, However, nasty rusted out single outlet exhaustplus Glide and 2 bbl took all the get-up-and-go out of the equation. Based on the iconic “double-hump” or “camel-back” (fuelie) cylinder heads of the ‘60s and early ‘70s—including the famed 461 Fuelie heads—the DHC 175 castings are modern aluminum versions with straight spark-plug locations and improved 60cc combustion chambers. 291 Camel hump head spark plugs. 291 Heads a Good Idea or Not?. The closed chamber shape produces on average 20 ft. Not a big deal but something to take into account depending on cam type choice which to me with the current lifters available would not be any choice. I have a 67 camaro with a large journal 327 bored 30 over with 2 valve relief pistons, stock 291 double hump heads, edelbrock performer intake, holley 650 with vac secondaries, hei with vac advance, comp cams 292h cam, and long tube headers. 60 @104-106mph every run all season long. I have double hump heads 291 casting. The double hump castings used on camaros in 1967 were 462 early and through mid year and then the 291's started showing up in April or May if I remember correctly. Even older is the troglodyte-like 64-cc chamber heads, often referred to as “double hump” or “camel hump” heads because of their distinctive casting marks on the ends of the heads. 3782461 327, 64-66 Double humpers or Camel hump 161/62cc port 3782461X 60-63, Larger intake runners, 172/64cc port 3991492 350 LT1, 70, 64cc, straight plug, camel hump. With a 383 you really will want 190-200cc ports. Cores Wanted: ‘186 & ‘492 straight plug “Double Hump” Chevy Small Block heads with accessory holes and ‘291 “Double Hump” heads, which do not have accessory holes. Chevy "Double Hump" Cylinder Heads. I think they should use a gasket seat type plug that takes a 13/16 socket. But the 291's i have are factory 2. The 461x heads though desirable for their bigger ports are basically all gone, used up and expensive. These heads also have. If torque is the OP main objective, the intake runner sizes of the 461, 462, 291, and 461X should make great torque due to the high-velocity ports that these heads offer. There is no discernible difference between a 291 and a 462 head. Find many great new & used options and get the best deals for (3927186) Chevrolet Small Block Double Hump Heads at the best online prices at eBay! Free shipping for many. Double-hump heads were popular performance upgrades for engines that were not equipped with them and are in high demand today in racing applications where factory heads are required. These castings are also becoming more difficult to find for collector car enthusiasts who need factory-correct components with matching ID numbers. With camel hump 291 heads, we proved they can make ~530hp on a 400 small block, which ran 10. In this video we discuss what is the best casting to start with for your application. 291s were on 327s thru 68 and are similar to 461s except have a temp sensor hole, 462s are similar but have a better combustion chamber. Double-Hump Heads from Trick Flow Give Modern Performance And Vintage Looks Double-Hump heads for the small-block are favorites among enthusiasts. com">291 heads vs 461 heads. was mounted on the driver's side. This setup is in s '67 Camaro so the search for parts is a bear seeing that one can't search by Y, M and M since the Camaro didn't come with a 400 and the 291 heads were not stock on anything I can find the 400ci in. I'm afraid the heads might need alot of work. 00 mind you I'm currently building a 305/nv3500 powered 1984 Ford Ranger, just a weekend toy, probably never going to see the strip but once or twice when i get a wild hair. These are Rebuildable bare original heads and perfect for a new set of 2. I believe these are the wrong plugs for these heads. I need a intake manifold that fits the ports on mu double hump 3782461 heads. 00 1967-68 Corvette Camaro Nova. All 68 4bbl and some 2 bbl CDN 327 Pontiac's used the 291 casting. I have a set of 291s on a 400ci (3951511, 4bolt) that I could use some help with. 00 per bare, stripped and cleaned head. 60 clean, unshrouded, untouched, so maybe 20 hours of work on them couldve gotten close to my edelbrocks, but kept them stock, they are a matching set. Trick Flow DHC SBC 175cc Aluminum Cylinder Head for Small. 1967 1968These are the highly sought after 64CC Double Hump Heads. If torque is the OP main objective, the intake runner sizes of the 461, 462, 291, and 461X should make great torque due to the high-velocity ports that these heads offer. Find many great new & used options and get the best deals for 3782461x SBC Double Hump Cylinder Heads 327 350hp at the best online prices at eBay! Free shipping for many products! item 5 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291. The Speedway heads come with a spring for flat tappet cams while the Trick Flows are equipped with hydraulic roller springs. Another one of many bad decisions I've made through the years. It featured 172cc intake runners and a slightly larger combustion chamber. I have double hump heads 291 casting. Hump Head 3917291 291 $500. See less See more Russ '67 4 speed coupe '67 rs coupe '94 6 speed z-28. These smaller chamber heads had better flowing ports than the later 441 or 882 castings. In this video we discuss what is the best casting to start with for you. 291's have a boss for the temp sending unit - some are not drilled , most are. 291's have a 64cc Combustion Chamber - You're looking at approx a 10. Made from premium grade, lightweight A356-T61 aluminum, DHC 175 heads feature the exterior styling and straight spark plug holes that deliver the nostalgic appearance of the original factory performance 186, 291, 461, 462 "double hump" or "camel back" castings that customers want. Hump Head 3917291 291 $500. The only good 882 head is a smelted down 882 head, used to make some other cast iron piece. I have double hump heads 291 casting. These heads also have 1. There was also a lower hp engine available with a 2 bbl but I don't know what heads they came with. These heads also have 1. Our new cylinder heads have a similar external look to the GM 3782461 heads. Casting numbers typically had seven digits, and heads were commonly recognized by the last three numbers. Other popular double-hump castings include the 291 (3917291), 292 (3917292), 186 (3927186), 187 (2927187), 414 (3973414) and 492 (3991492). Heads with the taller casting mark were produced in four casings. 291 double hump heads - $325 (Duncan) View larger image Ad id: 711205394695993 Views: 23 Price: $325. 1967 1968These are the highly sought after 64CC Double Hump Heads. com">double hump heads or vortech?. lbs more torque just from the better chamber shape, not even including the compression ratio gain. Chamber sizes varied from 62cc to 64 cc on all the camel hump heads except 461X which had 57. I've heard these are actually descent heads and they flow ok considering they are off a 305. Complete "Double Hump" heads with " Under­cover Porting ". 461 double hump heads were used on 1962 to 1964 300HP 327s from the factory along with larger exhaust and a carter AFB carb and used into 65 to 67 as I recall. Summit Racing™ Cast Iron Cylinder Heads for Small Chevy SUM. WHAT PLUG AND WHAT GAP WOULD YOU RUN THIS 350/295 THANKS Team Camaro 68 SS matching 4 speed Classic Camaro Reply Save Like R Rogers. Lastly I have a set of 305 HO 601 heads with 1. We have a good supply of used ‘186 & ‘492 heads available with everything from “Undercover Porting” to CNC Sportsman Porting. 291 Double Hump Heads Z28 SS Camaro Chevelle Nova Corvette - $300 (naples) Original date matching set of 67 291 Small Block Chevy Double Hump Heads. Have Y'all Seen the New Trick Flow Aluminum Double Hump Heads?. The "291" head was the first one to use the sending unit on the side. Intake manifold that matches the double hump heads intake??">Intake manifold that matches the double hump heads intake??. The 291s will also boost the compression on your 327. Put an intake valve in it´s place in both heads and check which head´s intake port will swallow more water. 00 DH-UC "Double Hump" castings, bare, machined for screw-in studs, new guides & " Undercover Porting ". Bryan, you said you´ve got #292 heads there. These can be made to flow very well with a competent three angle and some bowl blending. 8 5 product ratings 4 1 3 0 2 0 0. Matching heads reseated to run pump fuel. Lastly I have a set of 305 HO 601 heads with 1. Camel Double Hump Heads Cylinder GM Casting 3917291. The 67 and 68 302 used the 291 head as did the 327 and 350 and came with either the 2. I need a intake manifold that fits the ports on mu double hump 3782461 heads. Other popular double-hump castings include the 291 (3917291), 292 (3917292), 186 (3927186), 187 (2927187), 414 (3973414) and 492 (3991492). Even older is the troglodyte-like 64-cc chamber heads, often referred to as "double hump" or "camel hump" heads because of their distinctive casting marks on the ends of the heads. Assembled with 11/32" stainless steel valves, flat tappet springs, spring locators, steel retainers, machined locks, flat surfaced to your specifications. Double Hump Heads Which Head to run Cast Heads 4. Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump Sbc Heads 291 D 10 7. If torque is the OP main objective, the intake runner sizes of the 461, 462, 291, and 461X should make great torque due to the high-velocity ports that these heads. See more Reply Save Like 67 Plum · #9 · Jun 29, 2010 Vintage 68 said:. I alo have a MSD Box and Distributor. 00 291 double hump heads, fresh valve job, new valves, new z28 springs and new seals. The 186 head, unmilled generally runs out around 67-68 CC chamber size as it has a relief above the spark plug like the 291 and 462 castings do. Those heads were designed for 327 cubic inch engines with a 600 CFM carburetor and relatively small, old school cams. Plus, the decks and walls are cast extra thick to increase casting strength and provide plenty of material for future porting. Thread starter 79camaro327; We use to grind the "Double humps" off to a point , #896 and 520 castings to get around the rules. With camel hump 291 heads, we proved they can make ~530hp on a 400 small block, which ran 10. Summit Racing™ Cast Iron Cylinder Heads for Small Chevy Summit Racing Part Number: SUM-152123 UPC: 190861096202 Combustion Chamber Volume (cc): 72 Intake Runner Volume (cc): 165cc Cylinder Head Style: Assembled Cylinder Head Material: Cast iron Intake Port Shape: Rectangular Intake Valve Diameter (in. What kind of HP can a set of double hump. 60" exhaust valves, whereas most 461 heads came with a 1. The '68 model year saw the temp sending unit move from intake to head and this was the SBC performance head meant to deal with that. 018`` thick Shim Head Gasket and ideal with say a 280H-10 Cam to produce an 8. Sad part was I removed a set of aftermarket Dart iron heads that likely had 30hp more than the double humps that I had reworked done strictly to keep things more original. Find many great new & used options and get the best deals for 3782461x SBC Double Hump Cylinder Heads 327 350hp at the best online prices at eBay! Free shipping for. 55 valves & possibly the smaller 1. Both 462 and 291 castings were used on the 302 with 2. However, even with a 4" wide chamber and large valves, these heads will still fit on a. Wyatt and Joe compare them with the original GM 461 casting or "fuelie heads" that debuted on the 1961 Corvette with Rochester fuel injection. Is there a intake manifold that match the ports? If not I have read it’s important that the intake manifold has smaller ports then the heads, something about turbulence with sharp corners and edges. Cylinder Head Style: Assembled Cylinder Head Material: Aluminum Intake Port Shape: Rectangular Intake Valve Diameter (in. The double hump castings used on camaros in 1967 were 462 early and through mid year and then the 291's started showing up in April or May if I remember correctly. With the 291 heads, the straight-stem valves perform better. The only differences are most of the 906 heads have hardened seat inserts in the exhaust. The plugs that are in the motor now are AC #10 rapid fire taper seat plugs which take a 5/8 socket installed by the PO. With the 291 heads, the straight-stem valves perform better. hhott71. Report Last Updated on: May 4, 2023 with 291 double hump heads - $325 (Duncan). No CNC profiles or anytng like that. There was also a race version of the 461 known as the 461x. 60cc CNC-profiled combustion chambers combined with a state of the …. biggest cam for 327 and double hump heads, flat top pistons. The 291s will also boost the compression on your 327. item 5 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7 $700. The “double hump” or “fuelie” heads have been around since the 1960’s. The plugs that are in the motor now are AC #10 rapid fire taper seat plugs which take a 5/8 socket installed by the PO. Based on the iconic "double-hump" or "camel-back" (fuelie) cylinder heads of the '60s and early '70s—including the famed 461 Fuelie heads—the DHC 175 castings are modern aluminum versions with straight spark-plug locations and improved 60cc combustion chambers. The double hump castings used on camaros in 1967 were 462 early and through mid year and then the 291's started showing up in. Trick Flow has revived those nostalgic memories in a much-improved aluminum casting. Roller only & Trick Flow have a really good reputation on they're products. Find many great new & used options and get the best deals for Camel Double Hump Heads Cylinder GM Casting 3917291 at the best online prices at eBay! Free shipping for. There are a lot of castings to choose from when running the Chevy Double Hump heads. 94 valves and the 76cc chambers. 50 exhaust while the bottom head is the performance version (325hp and higher) used on 67-68 327 applications with 2. But this goes back to what was available back in the day. It had AC Delco R43S gapped at 35 degrees. Trick Flow DHC 175 cylinder heads are available fully assembled or as bare castings. Summit Racing™ Cast Iron Cylinder Heads for Small Chevy Summit Racing Part Number: SUM-152123 UPC: 190861096202 Combustion Chamber Volume (cc): 72 Intake Runner Volume (cc): 165cc Cylinder Head Style: Assembled Cylinder Head Material: Cast iron Intake Port Shape: Rectangular Intake Valve Diameter (in. Double-hump heads were popular performance upgrades for engines that were not equipped with them and are in high demand today in racing applications where factory heads are required. The 291's are the old double humps with 1. 3782461x SBC Double Hump Cylinder Heads 327 350hp. There is no discernible difference between a 291 and a 462 head. Makes them easy to spot at a swap meetyou're right they started using them mid 1967and all of 1968 production. 400ci sbc and double hump heads. The “double hump” or “fuelie” heads have been around since the 1960’s. Wyatt and Joe compare them with the original GM 461 casting or "fuelie heads" that debuted on the 1961 Corvette with Rochester fuel injection. 22 at 131-133mph every pass with 1/8 times 6. 291 Double Hump Heads Z28 SS Camaro Chevelle Nova Corvette - $300 (naples) Original date matching set of 67 291 Small Block Chevy Double Hump Heads. CNC-Machined Combustion Chamber: Yes CNC-Machined Intake Runner: No CNC-Machined Exhaust Runner: No Combustion Chamber Style: Heart Intake Port Location: Standard Exhaust Port Shape: D-port Exhaust Port Location:. Small Block Casting numbers Back to FAQ Home. Tickety Boo, Feb 22, 2021 SHARE POST #11 Deuces and Budget36 like this. double hump heads or vortech?. These are cheap and will make it work. The 291's are the old double humps with 1. These are Rebuildable bare original heads and perfect for a new set of 2. 291 heads are the same as 462's which are essentially the same as 461's. Depends on how budget you want to be and whats done With camel hump 291 heads, we proved they can make ~530hp on a 400 small block, which ran 10. The double hump heads, even the good ones, were good for a couple of reasons, one of which was because they could be effectively ported. Incidentally 1968 and 1969 was the year when they went from short water pump and associated bracketry to long water pump. If you wanted the heads to flow, they had to be ported by someone who knew what he was doing. 028 head gasket, you get to keep the quench and the aluminum heads should forgive compression enough to run pump gas. Chevy Double Hump Fuelie Heads. The 461 head had no chamber below the spark plug, it was machined flat when the head was. Find many great new & used options and get the best deals for Camel Double Hump Heads Cylinder GM Casting 3917291 at the best online prices at eBay! Free shipping for many products! item 1 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7 Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads. 291 Double Hump Heads Z28 SS Camaro Chevelle Nova Corvette - $300 (naples) Original date matching set of 67 291 Small Block Chevy Double Hump Heads. These are the 462 and 291 head. The 291's are the old double humps with 1. Even older is the troglodyte-like 64-cc chamber heads, often referred to as “double hump” or “camel hump” heads because of their distinctive casting marks on the ends of the heads. The 461 head had no chamber below the spark plug, it was machined flat when the head was made. After 1970, all of the production engines used the larger smog friendly, lower compression open chamber type heads. today you can buy 200+cc heads in Iron or aluminum for what a proper head work (money) charge is. 291's have a boss for the temp sending unit - some are not drilled , most are. The 275 hp 327 , the 302 and the 350 engines came with the 291 double hump heads. The 68 double hump heads were the 291 castings and they did not have accessory holes. HotRodWorks Alliance Vendor from Caldwell, Idaho. Chevy Double Hump Heads Specs. Cylinder Head Style: Assembled Cylinder Head Material: Aluminum Intake Port Shape: Rectangular Intake Valve Diameter (in. cylinder head Identification. Gui272 Registered 1956 Chevy Bel Air Post 350 sbc with 700r4 Joined Aug 23, 2022 272 Posts. 291 heads are the same as 462's which are essentially the same as 461's. com Click to expand Those are on my list and also the speedway motors version. Trick Flow Specialties TFS-30210002 Trick Flow® DHC™ 175 Cylinder Heads for Small Block Chevrolet | Summit Racing Free Shipping - Trick Flow® DHC™ 175 Cylinder Heads for Small Block Chevrolet with qualifying orders of $99. 00 1967-68 Corvette Camaro Nova Impala 3917291 Double Hump Bare Heads/Pr. 291 heads are the same as 462's which are essentially the same as 461's. These are the 462 and 291 head. even Ported you will be in the 180-185cc intake port neighborhood. com S SLIM Registered Joined Apr 20, 2011 5,736. The top head is the 'lower horsepower' version (300hp and under) used on 67-68 327 applications with 1. Find Trick Flow® DHC™ 175 Cylinder Heads for Small Block Chevrolet TFS-30210003 at TrickFlow. WHAT PLUG AND WHAT GAP WOULD YOU RUN THIS 350/295 THANKS Team Camaro 68 SS matching 4 speed Classic Camaro Reply Save Like R Rogers Performance · #7 · Aug 21, 2005. With the 291 heads, the straight-stem valves perform better. The 292 was the 327/350 head. These heads have the letters “CONV” cast in the valve cover area. Sad part was I removed a set of aftermarket Dart iron heads that likely had 30hp more than the double humps that I had reworked done strictly to keep things more original. The accessory holes came out in 1969 with the 186 heads. Is there a intake manifold that match the ports? If not I have read it’s important that the intake manifold has smaller ports then the heads, something about turbulence with sharp corners and. The '68 model year saw the temp sending unit move from intake to head and this was the SBC performance head meant to deal with that. Double-hump heads were popular performance upgrades for engines that were not equipped with them and are in high demand today in racing applications where factory heads are required. ** 291 Double Hump Head Job. Our new cylinder heads have a similar external look to the GM 3782461. Rated will jump to 10:1 though if you calculate/measure, probably 9. Get a set of RHS Pro-lightnings in cast steel and paint them orange. 02 Camel Hump Heads 291 $1,000. The 291's are the old double humps with 1. These heads have the letters “CONV” cast in the valve cover area. The top head is the 'lower horsepower' version (300hp and under) used on 67-68 327 applications with 1. Made from premium grade, lightweight A356-T61 aluminum, DHC 175 heads feature the exterior styling and straight spark plug holes that deliver the nostalgic appearance of the original factory performance 186, 291, 461, 462 "double hump" or "camel back" castings that customers want. These heads have the letters “CONV” cast in the valve cover area. I have ported 186 style Chevy heads to flow over 250 CFM intake flow. These heads have 2. 882 head is a 76cc smogger head, 291 is 64cc closed chamber head. These are cheap and will make it work much better. Chevy cylinder head Identification. Matching SetUsed in SS Super Spor 291 double hump heads - $325 (Duncan) 291 double hump heads, fresh valve job, new valves, z28 springs, and seals. 3917291 Double hump heads on a 1971 350?. Double Hump Cylinder Head Comparison. Based on the iconic “double-hump” or “camel-back” (fuelie) cylinder heads of the ‘60s and early ‘70s—including the famed 461 Fuelie heads—the DHC 175 castings are modern aluminum versions with. 00 shipping GM Chevy 3917291 Heads Camaro Corvette Double Hump 1967 1968 In Michigan $800. BIGZEKE92 Hit Em In Da Mouf Racing Joined Nov 9, 2010 15,445 Posts #3 · Jan 14, 2013. Double Hump Heads Which Head to run. 11K subscribers 493 67K views 3 years ago There are a lot of castings to choose from when running the Chevy Double Hump heads. I have acquired a freshly rebuilt set of 291 double hump heads with what seems like 2. What are the differences between the 291, 461 and 462 Castings? Which set of heads will work best? I was thinking of using a Comp Cams Magnum 270 Hydraulic Cam and Lifter Set. This setup is in s '67 Camaro so the search for parts is a bear seeing that one can't search by Y, M and M since the Camaro didn't come with a 400 and the 291 heads were not stock on anything I can find the 400ci in. Depends on how budget you want to be and whats done With camel hump 291 heads, we proved they can make ~530hp on a 400 small block, which ran 10. That came later on the 186 and 041 heads. If you want factory looks, go for the 292 turbo casting or 186's i believe they performed better. Reply Save Like 64nailhead · #5 · Dec 17, 2016 Cam selection is dependent on application. PLEASE VERIFY THE INTAKE PORTS OF THOSE AND THE #461 (x). So with the same pistons you get more compression (=power or problems with the #461 (x) heads. Matching heads reseated to run pump fuel. This combustion chamber design was used in all of the double hump heads including the 291, 462, 186, 041 and 492. These smaller chamber heads had. Which "old school" camel back head flows the best?. 291 Chevy Small Block Double Hump Camelback Fueler …. Speedway Motors sells a alumunum sbc double hump 64 cc head part #9103782461 Comes out to 10. CNC-Machined Combustion Chamber: No. You will get a few different answers but if you get 500HP N/A from them you have done well. SBC CHEVY 327 350 383 NKB-200cc ALUMINUM HEADS 64cc ANGLE PLUG NKB-272-A | eBay. I have a set of 291s on a 400ci (3951511, 4bolt) that I could use some help with. Those heads were designed for 327 cubic inch engines with a 600 CFM carburetor and relatively small, old school cams. 1968 smallblocks had the short water pump and the alt. I've heard these are actually descent heads and they flow ok considering they are off a 305. You will get a few different answers but if you get 500HP N/A from them you have done well. 040" over 283 engine, as well as the larger 327 Chevy.