Camel hump heads

item 7 OEM GM 3782461 Cylinder Heads Small Block Chevy Camel Hump 1964 2.02 1.60 Fuelie OEM GM 3782461 Cylinder Heads Small Block Chevy Camel Hump 1964 2.02 1.60 Fuelie. $895.00 +$88.85 shipping. See all 10 - listings for this product. 5.0. 5.0 out of 5 stars based on 1 product rating.

Oct 20, 2003. 3,212. Sitting in my command bunker waiting for the zombi. As stated, the value depends on the demand from someone who wants what you have. Just FYI, the DZ engine is 69 Z28 only, so would not be found in a 67. the F17 on the heads is likely the casting date - June 1, 1967. This is kind of late in the 67 model year production, …For port matching your intake and heads, you can find your ideal intake manifold gasket to use as a template. Holley Performance/Mr Gasket offers this port gauge I use with 28 popular port sizes for small- and big-block Chevy heads. The hard plastic material makes scribing your heads easier. The Tools Basic head-porting tools will not break the ...461 and 462 camel humps are good heads for the time. If you building a period specific engine or restoration such as a 350hp/327 they do the trick. You can get the 186 castings, they are 64 cc heads with accessory holes used on 69 302 and 70 350 LT-1 …Head and face reconstruction is surgery to repair or reshape deformities of the head and face (craniofacial). Head and face reconstruction is surgery to repair or reshape deformiti...There is a company out there that makes aluminum heads with the old double hump casting on the ends. Might be worth looking into. 1969 x-77 Z/28 orange/ white stripes, named by my daughter "Clementine ", M-22 close ratio, 4:10 12 bolt, CE 302. Hugger orange with white stripes.Jul 11, 2006 · the 462 and pretty much all the following camel hump heads had the D shaped chamber, and the spark plug location was moved with a large quench pad adjacent to it....these are the heads to use if you are going to run domed pistons, the 461's usually have some interference with domes and spark plugs. 461 View attachment 204412 462 View attachment ... As Doug pointed out there are 3 different casting numbers that have the double hump outside identification. If you look at the casting numbers and date codes on the heads you can get a better idea of the original application. The 291 heads are later 60's and generally are high performance. The 462's were used on early to mid 60's full size …

Chevrolet Small Block Camel Hump Heads (Small Camel Humps) In this video we get a tad bit confused over the Casting Numbers Watch me struggle to figure this ... Offered in 69-71, on high performance 350's, and as a service replacement for the 64cc heads. Basically the same as the 186/041, and supposedly still available at your local chevy dealer, under different p/n's. Later castings offered 1.44" diameter spring seats, and thicker spring seats.SBC Head shoot out Part 2Heres one for the Old school boys!Stock Vortec Heads VS Stock Camel Humps Vs Ported 2.02 Camel Humps!Very good info, Real flow data!...ARP 247‑4202 Head Stud Kit for 1998-18 Dodge Cummins 24v Diesel 5.9L 6.7L. Find many great new & used options and get the best deals for SBC 3927186 186 1969 Camel Back Camel Hump 300hp or 350hp Heads at the best online prices at eBay! Free shipping for many products!How to identify camel hump (aka double hump) small block chevy heads. Ryan Krizan. 224 subscribers. 161K views 15 years ago. ...more. This video shows you how to identify camel hump...

Aug 11, 2023 · The phrase “Camel Hump” or “Double Hump” heads comes from this casting boss with the two ears or bumps. These heads are some of the best factory heads ever produced. The L84 is essentially the exact same engine as the L76, but with Rochester mechanical fuel injection. Camel Hump Heads. High performance heads by Chevrolet, identified by two humps on the outside end of the casting.Sometimes we all need to rest our weary head, take pause and simply sit for a moment. It may not look pretty. We may look a mess. But, we are... Edit Your Post Published by Hang in...3991492. Jump to Latest Follow. 30K views 10 replies 7 participants last post by 2drpostL79 Aug 23, 2009. G. gregmontgomery Discussion starter. 203 posts · Joined 1999. #1 · May 18, 2009. can anyone give any info. on these heads .3991492 is the numbers are these good performance heads.thanks. Like.item 6 GM 3927186 Cylinder Heads Small Block Chevy Camel Hump 64CC F-18-9 1969 186 GM 3927186 Cylinder Heads Small Block Chevy Camel Hump 64CC F-18-9 1969 186 $675.00 0 bids 6d 16h +$125.00 shippingNov 30, 2021 · I started a build of a SJ 327 block with an older aftermarket 3.48” SJ crank. I was going to run it in my 57 with ported aluminum speedway motors camel hump heads, modified to take a staggered valve cover, and a heavily worked factory intake. I was hoping to squeak into the 12s with it.

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9.25:1, 600 brawler carb, performer intake, TF CH heads, STOCK 327/350 camshaft, 32° total timing...330HP@ 5400rpm and 358TQ@ 3700rpm.There are a few things to consider. The valve sizes and chamber volume are two. If they have 1.94" intake and 1.5" exhaust valves a 383 would probably benefit from 2.02" intakes and 1.6" exhausts. A lot of these heads had 64cc chambers and a 383 with flat top pistons will put the compression over 11:1. If you're running pump gas on the …Chevy SBC Assembled Aluminum Camel Double Hump 461 Cylinder Head made by Speedway Motors, for as low as $609.99. Talk to the experts. Call 800.979.0122, 7am-10pm, everyday.SBC Head shoot out Part 2Heres one for the Old school boys!Stock Vortec Heads VS Stock Camel Humps Vs Ported 2.02 Camel Humps!Very good info, Real flow data!...Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7. Opens in a new window or tab. Pre-Owned. $700.00. delcoenginesandcomponents (230) 100%. or Best Offer. Free shipping. 31 watchers. OEM Original 1967 327 Cylinder Heads Chevrolet Camaro. Opens in a new window or tab. Parts Only. $240.00.

ARP 250-4202 Ford Diesel Head Stud Kit. $526.59. Trending at $549.00. 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! Camel Hump head porting and setup. by postal123 » Sun Jun 11, 2023 5:24 pm. Gents, I'm just a hobbyist and this is my 2nd thread here and 2nd attempt at head porting. I bought a '65 K10 with 8k "rebuilt" 357 SBC. Flat top 4-eyebrow pistons, HFT cam measured 252/262, 202/214 109 ICL and 114 LSA. 492 angle plug heads, performer …There are a few things to consider. The valve sizes and chamber volume are two. If they have 1.94" intake and 1.5" exhaust valves a 383 would probably benefit from 2.02" intakes and 1.6" exhausts. A lot of these heads had 64cc chambers and a 383 with flat top pistons will put the compression over 11:1. If you're running pump gas on the …(Kitco News) - Kitco aficionados, it is now time to have your say in where you think gold prices are heading in the short-term.Read more on 'Kitco' Indices Commodities Currencies S...Looking to upgrade my cast iron 462 camel hump heads for aluminium 461 with 2.02 & 1.60 valves will buy bare heads so I can setup valves and springs myself. Has anyone used and or had problems with the aluminium Speedway or Trick Flow camel hump heads. To go on my factory 327 275 hp sbc in my 1967 Camaro. Cheers. Like. Sort by …Because in the history of the SB Chevy 283, the ONE and ONLY 283 to come with double hump heads from the factory, was the 1961 275hp or 315hp/283 fuel injected Corvette engine! Yep, one year only, FI only! If the engine stamp pad is coded CR or CS and has a cast date code for Sep 60 through Aug 61, it's a somewhat valuable piece of …Feb 28, 2020 · Chevy SBC V8 Bare Aluminum Camel Double Hump 461 Cylinder Head - https://www.speedwaymotors.com/Chevy-SBC-V8-Bare-Aluminum-Camel-Double-Hump-461-Cylinder-Hea... Learn about the origin, evolution and popularity of the double-hump or camel-back cylinder heads for small-block Chevy engines. Find out how to identify, restore and upgrade these classic …If original stle is what your looking for stick with the camel hump heads. If not bolt on aset of Vortecs and a vortec intake and be done. ... “462” double hump heads with 1.94/1.50 valves, Comp Cams XE262 with 218/224 duration @.050 and .462/.469 lift, 670 Holley on a Performer RPM intake, stock exhaust manifolds with a transverse …Aug 11, 2023 · The phrase “Camel Hump” or “Double Hump” heads comes from this casting boss with the two ears or bumps. These heads are some of the best factory heads ever produced. The L84 is essentially the exact same engine as the L76, but with Rochester mechanical fuel injection.

Trick Flow Specialties DHC 200 Aluminum Cylinder Heads combine the classic looks of 1960s-era ‘camel hump’ cylinder heads with CNC-ported airflow capabilities to give a small block Chevy a big dose of horsepower. You can see the heads for yourself at the Trick Flow Specialties booth #23011 in the Race and Performance Section, Central Hall.

Features like fast-burn combustion chambers, high-velocity ports, large diameter valve springs, and positive stop valve seals bring the vaunted camel hump heads into the 21st Century. Save yourself the hassles of hunting down original GM 3782461, 3782461X or 3890462 castings, only to find out they can't be saved.Trick Flow Specialties DHC 200 Aluminum Cylinder Heads combine the classic looks of 1960s-era ‘camel hump’ cylinder heads with CNC-ported airflow capabilities to give a small block Chevy a big dose of horsepower. You can see the heads for yourself at the Trick Flow Specialties booth #23011 in the Race and Performance Section, Central Hall.I can get a set of those “camel back” or “double-hump” heads—I think the cast number is 462. This is going to be a very mild 292 in my street rod and I might even add …Aug 11, 2023 · The original heads used on the L79 are the same as the L76 and L84, the famed “Camel Hump” 461 castings with 2.02”/1.60” valves. Keep in mind that most 461 double-hump heads have 1.94”/1.50” valves, only the select few used on L79, L76, and L84 engines had the larger valves. Step back in time with our modern reproduction of the iconic Chevy 461 double hump cylinder heads, now cast in lightweight aluminum! ... In this video, Joe and Wyatt discuss the features that bring the vaunted camel hump heads into the 21st Century. SBC 350 Build Combinations: Recipes for 300-600+ HP. Read More. The small block Chevy is still a ...Camel hump heads are very nice, and when properly pocket-ported can make some serious power. Why do you feel the need for accessory holes when the Header Power Brackets are available? These are made specifically for the camel hump heads without accessory holes, but will also work with the later heads with accessory holes that …As the decade wound down, the camel hump heads continued to endure with subtle tweaks for power improvements. After 1969 these were made with accessory bolt holes and 64cc combustion chambers. Like the previous camel hump heads, casting number 3927186 was offered in both small and large valve packages.

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ARP 134-3601 Head Bolt Kit - Chevrolet Small Block. (85) $87.06 New. ---- Used. Find many great new & used options and get the best deals for Camel+Hump+Heads+Casting+492+%26+292 at the best online prices at eBay! Free shipping for many products!The very FIRST double hump, camel hump, FI, "fuelie" (whatever you want to call it) head was installed on the 1961 315hp/283 Corvette fuel injected engine. THAT WAS THE ONLY ENGINE (at that time) TO GET THE HEADS WITH THE NOW FAMOUS 2 HUMPS on the ends of the head. SOOOOOOOOOOOOOOOOO, guess where the "fuelie" term originated.the 462 and pretty much all the following camel hump heads had the D shaped chamber, and the spark plug location was moved with a large quench pad adjacent to it....these are the heads to use if you are going to run domed pistons, the 461's usually have some interference with domes and spark plugs. 461 View attachment 204412 462 …Mar 9, 2003 · Camel Hump Heads Long ago, and I mean long ago, I knew all this stuff by memory. I believe the first camel hump head was on the 250HP or 275HP 327. Those heads had the 1.94 intakes. The 2.02's must have been on the 350HP or 365HP, and of course the Fuelies. I used to read Popular Hot Rod religiously and they had a project called Project X, a ... Look for last 3 numbers, example 461, Casting number 3767462 identifies Camel Back heads on 327 engines in 1962 to 1967 GM models. Number 3782461 is found on heads on the 1964 to 1967 models equipped with the 327. Number 3917291 can be found on the 302, 327 and 350 engines in 1967 to 1969 models. Number 3927186 is …Jun 11, 2023 · Camel Hump head porting and setup. by postal123 » Sun Jun 11, 2023 5:24 pm. Gents, I'm just a hobbyist and this is my 2nd thread here and 2nd attempt at head porting. I bought a '65 K10 with 8k "rebuilt" 357 SBC. Flat top 4-eyebrow pistons, HFT cam measured 252/262, 202/214 109 ICL and 114 LSA. 492 angle plug heads, performer intake with 600 ... 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. Chevrolet Small Block Camel Hump Heads (Small Camel Humps) In this video we get a tad bit confused over the Casting Numbers Watch me struggle to figure this ... ….

Chevy SBC V8 Bare Aluminum Camel Double Hump 461 Cylinder Head - https://www.speedwaymotors.com/Chevy-SBC-V8-Bare-Aluminum-Camel-Double-Hump-461-Cylinder-Hea...Erik Beckett Discussion starter. 710 posts · Joined 2001. #1 · Jul 11, 2004. I need to install some new plugs in my 327 but I am not sure what to go with. I have the 462 camel hump heads and right now there are NGK XR5's in that are a grey color on the porcelin. This the same set that came with the car when I bought it so I need to change ... Features like fast-burn combustion chambers, high-velocity ports, large diameter valve springs, and positive stop valve seals bring the vaunted camel hump heads into the 21st Century. Save yourself the hassles of hunting down original GM 3782461, 3782461X or 3890462 castings, only to find out they can't be saved. Heads: Iron “double-hump” 461 castings, 2.02” intake, 1.60” exhaust valves. Crank: Forged steel. L76 327 Engine Cam Specs: GM #3849346 Cast iron, Duntov “30-30” cam. ... The phrase “Camel Hump” or “Double Hump” heads comes from this casting boss with the two ears or bumps. These heads are some of the best factory heads ever ...Jan 13, 2021 · SBC Head shoot out Part 2Heres one for the Old school boys!Stock Vortec Heads VS Stock Camel Humps Vs Ported 2.02 Camel Humps!Very good info, Real flow data!... 0. 2.125/1.625. Gen III LS1 "GTZ" aluminum 38cc angle plug. 12480011. SB2.2 head 48 ~ 54 CC angle plug 284 CC intake runner Bare heads. 12480034. 2.02/1.60. Bowtie Phase III 64cc Angle plug 184 cc intake runner. 12506450.17921 posts · Joined 2007. #5 · Jul 17, 2020 (Edited) For the most part aftermarket heads come ready to accept both the 1955-86 head's intake bolt pattern and the 1996-2002 Vortec pattern. The real oddball is the 1987-95 pattern that looks like the 55-86 pattern but uses a different angle on the plenum bolts.Insider's Phil Rosen breaks down why credit agencies could still downgrade the country's creditworthiness in a no-default scenario. Jump to Happy hump day. Phil Rosen here. By now ...Oct 7, 2013 · This week, we add new valvetrain components to old “camel hump” cylinder heads. R.B. Las Vegas, NV. Q: I recently acquired a set of Chevy “camel hump” small block heads. I am putting in screw-in studs so I can use Harland Sharp roller rocker arms. Other than fitting the studs, do I need to do any machine work to the heads to use the ... biggest cam for 327 and double hump heads, flat top pistons. so i got a fresh 327 with flat top pistons and 462 camel hump heads all good, just need a cam. Im thinking around 282-286 degrees of advertised duration and around 470-500 lift, if i can go more duration i will. Ive read other threads of people recommending somewhere around 268 ... Camel hump heads, May 18, 2009 · 3991492. Jump to Latest Follow. 30K views 10 replies 7 participants last post by 2drpostL79 Aug 23, 2009. G. gregmontgomery Discussion starter. 203 posts · Joined 1999. #1 · May 18, 2009. can anyone give any info. on these heads .3991492 is the numbers are these good performance heads.thanks. Like. , Colleges and new high school graduates have what I think is a strange idea. They think every freshman is an ad Colleges and new high school graduates have what I think is a strange..., Camel hump heads are very nice, and when properly pocket-ported can make some serious power. Why do you feel the need for accessory holes when the Header Power Brackets are available? These are made specifically for the camel hump heads without accessory holes, but will also work with the later heads with accessory holes that …, JimKramer said: YES, I had my double hump heads drilled about 8 years ago. It worked great and they still do. However the machine shop will not guarantee it. So get a good machine shop that has done it before and knows the approximate location. Also the hole will be drilled into the inside of the head so after you install the alt and it's ready ..., the 400 has about 10.4:1CR with #187 camel hump heads, weiand intake and a new Holley 750 DP, forged pistons, a fairly radical cam (well we were told, I've heard it run for about 1min till next weekend) mini gear reduction starter, hooker headers, 3" exhaust, 4 core radiator, lakewood scatter shield , dual center force clutch, and the M21 …, The double hump heads were factory installed on all High Performance Fuel Injected and carbureted Chevrolet vehicles including Corvette, Camaro RS SS & Z-28, Chevelle Malibu, Chevy II Nova, Bel Air, & Impala. These heads will also interchange with other camel hump heads with casting numbers 461, 461X, 462, 291, 292, 186, 041, & 492., Sep 23, 2006 · 3973370 heads were used on 69/70 Chev or pontiac 350/300HP engines, at least in Canada they were. Basically same head as the 186. They were only availiable with the 1.94/1.50 valve . 2002 Jerry Bickle Cavalier, 446" Small Block, Brodix Canted Valve, lenco 5 speed, 7.54 @ 180. mph,1.06 60', 2235 lbs for 2014. GM Canada Docs, Highly Optioned 69 ... , the 462 and pretty much all the following camel hump heads had the D shaped chamber, and the spark plug location was moved with a large quench pad adjacent to it....these are the heads to use if you are going to run domed pistons, the 461's usually have some interference with domes and spark plugs. 461 View attachment 204412 462 …, For instance, the camel hump symbol (also called double hump) can be found on 461, 461X, 462, and 291 casting heads. The 492, 292, and 186 heads have a slightly different looking camel hump. These heads may have come with 1.94/1.5-inch valves or they might have been made with 2.02/1.6-inch valves. , Mar 9, 2003 · Camel Hump Heads Long ago, and I mean long ago, I knew all this stuff by memory. I believe the first camel hump head was on the 250HP or 275HP 327. Those heads had the 1.94 intakes. The 2.02's must have been on the 350HP or 365HP, and of course the Fuelies. I used to read Popular Hot Rod religiously and they had a project called Project X, a ... , The "right angle" (triangle 041) heads are just as good as "double hump" heads. If I'm not mistaken, they are the factory replacement heads for the "double hump". As was mentioned already, the original double hump heads didn't have accessory holes, but the right angle heads do. Outside of that, they are pretty much the same., all news. Original Camel Hump Heads. I just finished up machining two sets of heads for a customer replicating camel hump heads for a Camaro restoration. He wanted high …, steve70malibu. According to my information, 461X was the best of all the camel hump heads but are very rare. Next comes the 492 castings, next the 461, then 186, then 041s which are not camel humps but have the same design. I have a print out from a website that lists all sb heads and information on all of them., Oct 13, 2020 · Re: camel hump vs vortec. by ProPower engines » Tue Oct 13, 2020 7:50 pm. No comparison. The vortec heads are better in every way unless you have free double bump heads and have to pay for the vortec's. If you flow the early GM heads and flow the vortec heads and compare the numbers. The big difference is in the chamber shape. , Original Camel Hump Heads. I just finished up machining two sets of heads for a customer replicating camel hump heads for a Camaro restoration. He wanted high performance heads that looked just like the originals. I machined the logos off and then machined the inset by hand around a 3/8” thick steel guide. After the rough machining was ..., Head and face reconstruction is surgery to repair or reshape deformities of the head and face (craniofacial). Head and face reconstruction is surgery to repair or reshape deformiti..., Trick Flow® DHC™ 175 Cylinder Heads for Small Block Chevrolet. Nostalgic appearance—check. Modern performance—check. The best of both—checkmate! Trick Flow’s DHC 175 cylinder heads give small block Chevy enthusiasts a new performance option. No longer will anyone have to choose between vintage looks or modern cylinder …, I want to put a power steering pump in my 67 rs camaro. I have a 327 with the camel hump heads. I have no brackets and only two holes to work with for mounting because of the heads. My alternator bracket already mounts to the exhaust manifold. Do i need an adjustment bracket or just the main bracket that holds the pump. Hellllllllllllllllllllp., item 8 OEM GM 3782461 Cylinder Heads Small Block Chevy Camel Hump 1964 2.02 1.60 Fuelie OEM GM 3782461 Cylinder Heads Small Block Chevy Camel Hump 1964 2.02 1.60 Fuelie $895.00 +$88.85 shipping, Dec 26, 2007 · Camel hump heads are way over rated in this day and age. You could gain a little more power from them by porting and cleanup. I ported my Sportsman IIs using a high speed steel cutter on a Dremel tool. It took forever, but it worked. I guess it depends on how confident you are with a Dremel.-You could take the sharp edges off of the short turn ... , Chevy 3917291 Heads 302 327 350 Double Hump Pair Camel Hump SBC Heads 291 D 10 7. Opens in a new window or tab. Pre-Owned. $700.00. delcoenginesandcomponents (230) 100%. or Best Offer. Free shipping. 31 watchers. OEM Original 1967 327 Cylinder Heads Chevrolet Camaro. Opens in a new window or tab. Parts Only. $240.00., I started a build of a SJ 327 block with an older aftermarket 3.48” SJ crank. I was going to run it in my 57 with ported aluminum speedway motors camel hump heads, modified to take a staggered valve cover, and a heavily worked factory intake. I was hoping to squeak into the 12s with it., VERY FEW Camel hump heads came from the factory with 2.02 x 1.65 valves. Many of the heads listed were available with both sizes, but only the high horsepower solid lifter type engines got the 2.02's. ... Double hump heads have the humps or "bumps" cast into the end of the heads. The early ones had two large humps …, 962 posts · Joined 2004. #2 · Mar 22, 2009 (Edited) 383 with camel hump heads. You're going to be up there on the compression ratio, and Hi-Test fuel will be a requirement. Be sure and get your "quench" set right from the start, somewhere in the area of .035 to .045. 7., I have acquired a freshly rebuilt set of 291 double hump heads with what seems like 2.02 intake valves, and a 400ci 511 block that is allegedly 0.040 over already. All for $0.00 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., Vortex intercepts high-grade silver with goldNew target discovered east of BrimstoneCentral and Camel zones convert waste to mineralizationWINNEMU... Vortex intercepts high-grade s..., Colleges and new high school graduates have what I think is a strange idea. They think every freshman is an ad Colleges and new high school graduates have what I think is a strange..., Dec 26, 2007 · Camel hump heads are way over rated in this day and age. You could gain a little more power from them by porting and cleanup. I ported my Sportsman IIs using a high speed steel cutter on a Dremel tool. It took forever, but it worked. I guess it depends on how confident you are with a Dremel.-You could take the sharp edges off of the short turn ... , Camel Hump Heads Long ago, and I mean long ago, I knew all this stuff by memory. I believe the first camel hump head was on the 250HP or 275HP 327. Those heads had the 1.94 intakes. The 2.02's must have been on the 350HP or 365HP, and of course the Fuelies. I used to read Popular Hot Rod religiously and they had a project …, Jun 11, 2023 · Camel Hump head porting and setup. by postal123 » Sun Jun 11, 2023 5:24 pm. Gents, I'm just a hobbyist and this is my 2nd thread here and 2nd attempt at head porting. I bought a '65 K10 with 8k "rebuilt" 357 SBC. Flat top 4-eyebrow pistons, HFT cam measured 252/262, 202/214 109 ICL and 114 LSA. 492 angle plug heads, performer intake with 600 ... , Sorry 462 camel hump casting hoarders, Trick Flow is bringing back an aluminum version of the classic camel or double hump heads for the Chevrolet small block. If you are not familiar with the ..., 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. These smaller chamber heads had better flowing ports than the later 441 or 882 castings., Dec 12, 2018 · Originally sold bare, so valve sizes are dependent on machining. All 400ci small-blocks utilize Siamese cylinder walls. This design caused the cooling system to develop hot spots and that is why the 400 heads have steam holes. 25534351C: 2004 Bow Tie, cast-iron, Vortec, 175cc intake ports, 65cc exhaust ports, 2.02/1.55-inch valves.