Among these components, cylinder heads play a crucial role in determining an engine’s power and efficiency. In this article, we will compare two popular choices: the …I then went to a turbo setup, making 639 rwhp @ 8 PSI on 317 heads. I was anticipating some 10.4 second or possibly faster ET's, in good weather, with the additional 130 rwhp. Well before I got a chance to get the car to the track I blew a few pistons and rebuilt the motor with stock pistons but 317 heads in effort to lessen the horsepower some.862 heads vs 243. The 862 casting number represents the 862 cylinder head. The 862 heads came on all LQ9 6.0 engine blocks and are completely interchangeable with the 243 cylinder head. Both the 243 and 862 heads have the same 64cc combustion chamber, but there are some very slight differences in the pore size of the two heads.hivoltagedriver. Port and polish on a set of 243's is usually ~20hp. A set of ported 243's on your LS1 should make a sizable difference, especially with a cam. '09 PSM G8 GT w/ Premium & Sport packages. Go: Kooks 1 7/8" LTs, catless mids, Corsa, VCM OTRCAI, Rick C. AirRam intake and ported TB, tuned by me.Porting the 243 heads is an effective way to improve airflow into and out of the engine, as it involves modifying intake and exhaust ports for greater efficiency. With this modification, air flows more easily into the combustion chamber which results in increased power output. ... Which heads are better 706 vs 862? Sometimes the difference ...CI 6-7-8-9-10 Veteran. St. Jude Donor '03. Yes, the 243 and 799 heads are now being used on later model (05+) 4.8 and 5.3 truck engines. Reason being is they changed from dished to (now) flat top pistons in those engines, which required the larger head chamber to keep compression ratio about the same.Even stock 243 heads flow great. AFR did a comparison between many different heads vs their AFR 215 & 225s on another site and the stock 243s stepped up hard even matching the 225s flow at .550 lift and besting the 225s at .600 lift (albeit on a 4.125 bore which is pretty big, LS1 is 3.90 and LS2 is 4.00).When it comes to the GM's LM7 engines, the 862 cylinder heads are an integral part. Constructed from lightweight aluminum material, these cylinder heads feature a 61cc combustion chamber volume for improved efficiency and performance. The intake port is shaped in a classic cathedral design while the exhaust port has an oval shape for better ...The 5.3 heads will have a casting number of 862 or 706. The 5.7 heads can have 806 (97-98 perimeter bolt), 241 or 853 (99-up LS1 heads), and 243 (LS6/LS2 heads). The factory chamber on a 5.3 head is approx. 61cc. Some guys will use 5.3 heads to up their compression. The heads flow like a LS1, but have the smaller chamber.Fits. The price listed is for you sending your cathedral port cylinder heads (4.8/5.3, LS1, LS6, LS2, LQ4/9) to us for porting. Our stage 1 porting service will include the re-use of the stock vales. Stage 2.5 will include aftermarket 2.02/1.57 stainless steel valves. We also offer valve spring upgrades. PRC CNC Porting/Machining Service Includes:I have GM MLS head gaskets with a 0.051" compressed height and am planning for 0.010" out of block for a 0.041" quench. This should net me a compression ratio of 11.16:1. ... LS3 aluminum block (4.070" bore), 3.622" stroke, 243 64cc heads, flat tops with -3.2cc valve reliefs, 0.051" GM MLS head gaskets. combo will use a 228r cam, ported 243's ...Sort by: Add a Comment. J8ke_Stampede. • 1 yr. ago. There's no debate, it's been proven the 862/706 heads will make more power than the 317's. 317's and 241's are the worst factor LS heads. It's also not only because the chamber size and compression ratio either. 862/706 heads have higher velocity and better coefficient of discharge. 8.706 heads tend to be more popular than 243 heads with those who run naturally aspirated engines. While they don't have the same size combustion chamber they also don't have the tendency to lower the compression ratio and reduce horsepower. When looking to replace your heads, they offer a high degree of consistency since they are ...The LQ4 is a 6.0L LS (Gen. 3) small block engine used in GM trucks between 1999 and 2007. For marketing purposes, it was also known as the Vortec 6000. The engine specs and information listed here is for the stock LQ4 engine. Mechanically similar, General Motors’ LS and LS-based Vortec engines wound up on almost every branch of the GM …The 243 vs. The 799 Cylinder Head. As you have most likely caught on by now, these two cylinder heads are practically the same. The main difference between the 243 and 799 cylinder heads is that the 243 was used on older engines from GM Research, while the 799 has been used on newer engines from multiple manufacturers.Here’s my thinking. The 243 has. 2.00 intake and 1.55 exhaust with a 65cc combustion chamber. The 706 has. 1.89 intake and 1.55 exhaust with a 61cc combustion chamber. If I have a set of 2.00 intake valves put in the 706 with the smaller combustion chamber wouldn’t I have a better head with more compression and that’s not counting if I ...243 heads on 5.3l. Thread starter riccotxtre; Start date Jun 26, 2020; Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission. Jun 26, 2020 #1 R. riccotxtre TYF Newbie. Joined Jun 19, 2015 Posts 14821's and 5364's are identical as a bare head. You can swap them without a difference. The only difference is the 821's can be a LS3 head and have the lighter intake valves and yellow valve springs but still them same head and flow. The only time you are going to see a performance difference is when there is a casting shift that affects the ...GM never made an iron LS1. Look at the front of the block and it will clearly have the displacement cast into it. If it is a 5.3, slap some 243's on it and a punchy mid range cam in it and it'll be a good street brawler. If it is a 4.8, some aftermarket heads with revised valve angles and dual valvesprings (TF Gen X 205 for example) and a cam ...St. Jude Donor '03. 853 and 241 are basically identical. 853 was used on 99-00 LS1 engines. 241 was used on 01-04 LS1 engines. They both have a 66.67 cc combustion chamber (10.1 CR), 200cc intake runners, and 70cc (round) exhaust ports. The 243 head is the 01+ LS6/LS2 head.243/799 are functionally the same, as @art notes the difference is casting facility location. The 243's have a slightly smoother cast around some exterior edges, but the machining is identical and they flow and work exactly the same. 02'-04' Z06 Vettes were the only vehicles that came with sodium filled valves in 243 heads.It happens to even the best DIYer: the simple process of removing a screw becomes a struggle when the screw refuses to budge and the head of the screw becomes stripped. But not all...Richard Holdener. 293K subscribers. 2.7K. 174K views 4 years ago WESTECH PERFORMANCE GROUP. ...more. 706 5.3L HEADS vs 241, 799/243 vs 317s. WHICH …The 241 castings feature 205cc intake ports, 70cc exhaust ports, and a 2.0/1.55 valve combination. The hot factory heads would be the LS6 (243 castings), but even the stock LS1 heads can be made ...I ported my 862 heads on my LM4 5.3L with a SS2 cam I haven't re run the car yet but I'm sure it made a difference up top. It feels like it pulls harder on the top end and I had to add some fuel up top so that tells you right there its moving more air. It would take quite an effort to improve the port work of the 799, less so with the 862 but ...118. Intake valve is 2" on the 241, exhaust valve is same size as the 862. If planning on 241 heads on a 5.3 you will lose compression and hp. The Fleet... 2003 Suburban- 5.4 L59 331CI 10:5.1 Compression -Built by ME. 2004 Avalanche- 5.7 LS1 -NOT built by me. 2005 Silverado RCSB- 5.7 LS6 -Built by ME. Reply With Quote.862 s Vs 243 s..... So what the difference between some milled 862s and some stock 243s? Also how big of a difference would the 243s and a nnbs intake do on a 2003 4.8?806 and 243 use the same valve diameter 2.00I 1.55E. The valve lengths are different. ls6 243s use a longer hollow stem intake and hollow stem sodium filled exhaust. LS6 valves are 0.6mm or 0.023622. Obviously then my valves must have come in the 243s I bought. However mine were not off a Z06, so the valves were not sodium filled.GM's 5.3L LS1 head casting serves as the basis for this high compression / naturally aspirated oriented 3.900" bore specific offering. With your 5.3's, lightweight Manley Race Master Stainless valves, and lots of available P2V this is a great option for 440-480rwhp 3.900" bore builds. Our GM 5.3L CNC work will generate 11:1 compression on a ...However, the main distinguishing feature of the 862 cylinder head design is its unique ability to dramatically enhance air compression delivered following porting. While some may argue that the 243 heads are better, 862 heads deliver improved airflow, quality, performance, and power. Moreover, 862-cylinder heads are compatible with many cars.Jun 11, 2020 · 64nailhead. 4523 posts · Joined 2012. #5 · Jun 13, 2020. Here's your decision - the 317's will work better if you're looking for boosted 1000+ HP, but the 243's will work better everywhere below that. Something to keep in mind, old school SBC and SBF static and dynamic compression ratios do not apply to LS heads.The valves on LS3 heads are designed to be larger than those on stock LS heads to improve airflow, leading to increased power output. Standard valve sizes for LS3 heads include 2.165 inches (intake) and 1.590 inches (exhaust). However, it's not uncommon for LS3 heads to feature even larger valves. For example, some aftermarket LS3 heads may ...The 243 heads were utilized in the LS6 engines manufactured between 2001 and 2006. These heads are known for their exceptional power and efficiency. ... Recommended: 862 Cylinder Heads - A Detailed Overview. What LS comes with 317 heads? LQ4 engines got Generation III 317 V8 head in 2001. It has cathedral-like intake ports and a D-shaped exhaust.Remember, not all 243 heads are LS6 heads, but all LS6 heads are 243 castings. True LS6 heads will have the stainless steel hollow-stem valves. ... 373/873 LQ4 iron heads - 71.06cc. 706/852/862 ...Pretty good snowstorm today. I did the Caddy lifters at the suggestion of Ryan at GPI along with some LS3 intake valves. The hollow LS3 valves were significantly lighter than L92 valves. If I remember correctly it was something like 89g for the LS3 valves and 123g for the L92s. Lets Go Brandon!In its latest form, the LS3 has followed the 5.7L LS1/LS6 and 6.0L LS2 engine configurations by starting with an increase in displacement, checking in at 6.2 liters. This came courtesy of an ...The 799 cylinder head is a better choice than the 243 cylinder head because it has more capacity. Cylinders are the chambers in an engine where the fuel-air mixture is ignited by the spark plug. The combustion of the air and fuel inside a cylinder creates pressure, which forces out a piston on one end. A cylinder head is a part of an engine ...It still used 799/243 heads but also utilized variable valve timing and had flex-fuel capability. Chevy also used a 5.3L engine that was only in vans produced from 2010 to 2014, known as the LMF engine, identified by a number 4 in the 8th digit of the VIN. ... some include 1218 springs and the Elgin 228/230 cam. If your truck has 862/706 heads ...Are you looking for a new shaver head for your Norelco electric razor? If so, you’ve come to the right place. In this article, we’ll provide you with all the information you need t...243 04 up LS6 aluminum center bolt 5.7 ***These castings were also used around 05 in truck applications*** 862 99 and up 4.8-5.3 Truck heads 706 99 and up 4.8-5.3 Truck heads 799 05 and up 4.8-5.3Truck heads ***reportedly came on a few corvette's too*** These are basically 243 Heads 873 99-00 LQ4 6.0 Iron center bolt headsIntro to the LMG Engines. The LMG came in GM trucks and SUVs in 2007-'14 and made between 310-326 horsepower horsepower right out of the box. It's a Gen. 4 5.3L iron-block engine, so you're getting the better intake manifold, connecting rods, and ECM. The engine also had 799 or 243 casting heads which are closely related to the LS6.Oct 14, 2017 · I know stock vs stock the 243 is the superior head but my engine came with 706 non crack-tec heads and I'd like to use them if I could. My question is what performs better, a stock 243 or a professionally hand ported 862/706 because for the price of 243s I could have my 706s hand ported and flowed by a well known drag racer/engine builder in my area.799 LS Engine Cylinder Heads are some of the most recent cylinder heads on the automotive parts market. The cylinder cast architecture is with a semi-permanent mold method. The 799 cylinder heads are in the similitude to the 2004 LS2 cylinder heads due to the triangle casting marks similarity. However, unlike the 243 heads, they do not require ...The Pro 243 irons also feature a wider flow microslot than the 223s which made for better low-face forgiveness. They also feel smoother through the turf. The Mizuno Pro 243 irons retail for $1400. Overall. Given that the Pro 223's and 243's are meant to be the more forgiving Mizuno models, the Mizuno Pro 243's do in fact surpass the 223's.243/799 are functionally the same, as @art notes the difference is casting facility location. The 243's have a slightly smoother cast around some exterior edges, but the machining is identical and they flow and work exactly the same. 02'-04' Z06 Vettes were the only vehicles that came with sodium filled valves in 243 heads.Get the best deals for ls 243 heads at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items! Skip to main content. Shop by category ... GM LS 706 806 862 241 799 862 243 CYLINDER HEAD REBUILD SERVICE 3 BUISNESS DAY. Opens in a new window or tab. Remanufactured. $459.99. Save up to 10% when you ...Jul 31, 2020 · The Gen III have 862/706 Gen III heads, and the Gen IV have 243/799 heads. The 862/706 heads have smaller combustion chambers than the Gen IV, raising the compression ratio when swapped directly.799 is a 5.3 liter head. My 5.3 came with 862's, and my chambers are 61 cc. ... Some LS2's also came with the 799 heads. As stated above they are the same as 243 heads with a different casting method. They should have 64cc chambers. Save Share. Like. 0 Reply. S. ... plus they did the 317 headed 6.0L before they did the L92 headed ones. 345hp vs ...GM never made an iron LS1. Look at the front of the block and it will clearly have the displacement cast into it. If it is a 5.3, slap some 243's on it and a punchy mid range cam in it and it'll be a good street brawler. If it is a 4.8, some aftermarket heads with revised valve angles and dual valvesprings (TF Gen X 205 for example) and a cam ...European heads of state are meeting today in Brussels for their latest bout of dialogue on the EU crisis. European Council president Herman van Rompuy writes, “The main purpose of ...Just picked up a set of 862 5.3l heads for $100 and was wondering how well they will work for me. I have a forged 346 and the pistons have a small dish. I haven't done the math but the CR is around 9.2-9.4:1. I want to bring the CR back up to around 10:1. My plans are to hog the heads out and throw in some big valves and have them milled to get ...The exhaust port is a unique D-shape that improves flow. LS6 heads are the best choice only when all-out power is needed. Be prepared for a big price tag at the dealer or steep core charge from your head porter. 706 & 852 & 862 Head: 1999+ LR4 4.8-liter Truck 1999+ LM4 / LM7 5.3-liter Truck Material:Aluminum Part Number: 12559852, 12561706,12559862It happens to even the best DIYer: the simple process of removing a screw becomes a struggle when the screw refuses to budge and the head of the screw becomes stripped. But not all...We may earn a commission for products purchased through links on this page1291 posts · Joined 2007. #12 · Feb 3, 2010 (Edited) i purchased at set of 799 heads last summer for $100.00 bucks ,from another member on this forum. keep us posted when this project is complete. im going the budget daily driver route myself. i will be topping mine of with a fast,and a ported throttle body.Casting Number 706 and 862 Head: 1999+ 4.8L / 5.3 Liter Truck Material: Aluminimum Part Number: 12559862 12561706 Combustion Chamber Volume: 61.15cc Compression Ratio: 9.5:1 Intake Port Volume: 200cc Exhaust Port Volume: 70cc Intake Valve Diameter: 1.89 inches Exhaust Valve Diameter: 1.55 inches.Wanting to tax the flow capacity of the cylinder heads, we installed an aggressive hydraulic roller cam from Comp Cams. The LSR cathedral-port profile offers 0.624 lift (with 1.7:1 rocker ratio), 239/247 duration (at 0.050), and a 114-degree lobe-separation angle. The lift was slightly higher with the 1.72 roller rockers run on most of the heads.The Gen III have 862/706 Gen III heads, and the Gen IV have 243/799 heads. The 862/706 heads have smaller combustion chambers than the Gen IV, raising the compression ratio when swapped...Get the best deals for ls 243 heads at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items! Skip to main content. Shop by category ... GM LS 706 806 862 241 799 862 243 CYLINDER HEAD REBUILD SERVICE 3 BUISNESS DAY. Opens in a new window or tab. Remanufactured. $459.99. Save up to 10% when you ...Head gasket repair can be an expensive, but necessary repair for your vehicle. Knowing the average cost of a head gasket repair can help you budget and plan for this important main...I’ve been offered a 5.3 block with 243 heads on it for $300. Would the stock 243 heads work better on it than the 862 heads? Obviously they need to go to the …The 5.3 heads will have a casting number of 862 or 706. The 5.7 heads can have 806 (97-98 perimeter bolt), 241 or 853 (99-up LS1 heads), and 243 (LS6/LS2 heads). The factory chamber on a 5.3 head is approx. 61cc. Some guys will use 5.3 heads to up their compression. The heads flow like a LS1, but have the smaller chamber.Heads/Cam/Intake Manifold/Internals ...933: Found on 1997 LS1 engines up to mid-September. Although 862 and 706 heads share many similarities, the primary difference is that the 706 heads are made using SPM (semi-permanent mold) while the 862 heads are not. This makes the 706 heads slightly superior. Cylinder Head.3012 posts · Joined 2008. #1 · Apr 14, 2012. I have a 2004 Aluminum 5.3 with 70k miles that has 862 heads on it. I also have a set of 243 heads off of a 2009 Aluminum 5.3. Which heads should I use? I've been told the 243's flow better and the 862's supposedly raise compression .5 a point.Sniper's Hide is a community of Snipers of all kinds, focusing on long range shooting, accuracy, and ballistics. Founded by Frank Galli in 2000, Sniper's Hide has been offering informational videos, podcasts, and other support to its users in one location. Forum Statistics. Threads. 474,737.If you're contemplating 862 heads Vs. 706, the 862, and the 706 heads are awesome vehicle cylinder heads. However, the 706 heads are more sophisticated than the 862 heads. ... is a major concern between 862 heads Vs. 243. The cracks can lead to coolant leaking into oil space, thereby resulting in severe engine damage.Among the Dart Pro 1 LS offerings is a 225cc cathedral intake port head with a 62cc combustion chamber and 2.05/1.60-inch stainless valves. The advantage to this head, besides the improved airflow, is the 6cc smaller chamber that will bump up the static compression over a half a ratio—from 10:1 to closer to 10.6:1 (and perhaps more).Well, I switched from the 223 to the 243. Two reasons: first, the shafts in my 223s were not the correct shafts ( too light 105g); and, second, the gapping on the the 223 made no sense with 5* difference on the scoring clubs (8 thru GW). Findings after 4 rounds. The spec for the shafts is .25 inches longer. The head is definitely smaller.Start with squeezing your quench by using a thinner head gasket. A 0.040" gasket will give you an optimal quench distance and substantially reduce detonation, meaning you'll be able to run more timing. If you still haven't reached your SCR/DCR goals, I'd start removing material. 2004 Pulse Red M6.Damage Inc. 1174 posts · Joined 2007. #5 · Jan 30, 2009. The 317's are basically the same head as the 243's with a much larger chamber. I wouldn't doit. By the time he mills enough off to get your CR back they may be abit thin on the suface. I'd find some 243's and get them worked. They are easy to find these days.862 heads vs 243. The 862 casting number represents the 862 cylinder head. The 862 heads came on all LQ9 6.0 engine blocks and are completely interchangeable with the 243 cylinder head. Both the 243 and 862 heads have the same 64cc combustion chamber, but there are some very slight differences in the pore size of …The LQ4 is a 6.0L LS (Gen. 3) small block engine used in GM trucks between 1999 and 2007. For marketing purposes, it was also known as the Vortec 6000. The engine specs and information listed here is for the stock LQ4 engine. Mechanically similar, General Motors' LS and LS-based Vortec engines wound up on almost every branch of the GM family ...BARE GM LS 243 HEAD - 4.8L, 5.3L & 6.0L. Generation III V8 cathedral intake port cylinder head. Casting 12564243. For truck, van, SUV and perfomance applications. Used on LS6, L33, L20, LH6, LY5, LMG, LC9,LS4, LH8, LS2, LFA, LZ1 engines. Generation III cylinder head for V8 truck, van, SUV and perfomance applications often called an LS6 head. It ...Part 6 of the LS 5.3L Build will cover Installation of the 862 Aluminum Heads, Lifters, Pushrods, and Rocker Arms. Project Rowdy is a restoration on a 1979 J...The 862 head is commonly utilized in high-performance cars, racing, and sports cars. It's also found in some luxury and sports cars. The 862 is a 12-valve design that utilizes two intake valves per cylinder and one exhaust valve per cylinder. The combustion chamber volume is 84cc for the 862S, 83cc for the 862C, 84cc for the 862F, 82cc for ...After installation of the heads, offset rockers, and FAST LSXR intake, the LS3-headed stroker pumped out 581 hp and 543 lb-ft of torque. Note the LS3 heads increased both peak power and torque, though the rec-port heads did lose out to the 317s below 4,000 rpm. Despite the slight loss down low, torque production with the LS3 heads bettered 500 ...Our fellow tech writer and dyno-flogger Richard Holdener reports a gain of roughly 15 hp with stock 5.3-liter heads on a 6.0-liter. Our 5.7-liter head test bumped the average power by 9 hp but ...The biggest difference is price, .. 18* heads can be had for around $3200. while a professionally ported set of new SB2.2's built for your application. can cost over $5500 bare, .. Hope this helps, .. Curtis. Race Flow Development.can you make more than 500 hp na with stock 706 heads? do 799 heads make more hp than 706 heads? what makes more hp, rec port or cath port heads?Showing the port work on my 862’s setup for a small 4.8 build. Goal 375-425hp at the crankshaft prior to the Turd-Bo turbo install! 👍862 castings 20022.00/...I'm having a hard time finding a set of 243 or 799 heads, so I was considering having my 317's milled approx. 25-30 thousandths and going with an .040 head gasket to bump up the compression. ... Lets compare the heads: Casting Number 706 / 862 Head: 1999+ LR4 4.8 Litre Truck 1999+ LM4 /LM7 5.3 Litre Truck Material: Aluminimum Combustion ...May 12, 2013 · 1231 posts · Joined 2007. #1 · May 12, 2013. Have a stock bottom and 5.3. The heads on it right now are 862's. I'm approaching 20psi on the engine. Would it be worth it to switch to some ported and milled .025 317 heads? Running pump gas/c16 mixed. 1980 Chevy luv truck. Stock 6.0.These large-runner heads have a 12-degree valve angle, like stock, and are compatible with factory LS7 rocker arms and stands. The heads can accommodate 1.625-inch-diameter springs, and several are available. A 4.125-inch-or-larger bore is required. Base price is $1,130 each, fully assembled, through Summit Racing.The AP220SP is the biggest 23* head All-Pro has before you get into raised runner designs. It is also standard valve spacing. Flow numbers @ 28" of water. All figures in CFM. All-Pro AP220-SP-23* --- ~$3,350 (uses standard valve train and fully CNC'd runner) Intake 219cc Exhaust.The biggest difference is price, .. 18* heads can be had for around $3200. while a professionally ported set of new SB2.2's built for your application. can cost over $5500 bare, .. Hope this helps, .. Curtis. Race Flow Development.By Paul Johnson - March 9, 2016. This article applies to Chevrolet Camaro and Pontiac Firebird (1998-2002), as well as all LSx engines. The cylinder head (or "head") has several main functions. Its first order of business is …806 is the casting # of the heads . Its on the front corner . 806 is the worse flowing LS1 head and has perimeter valve cover bolts .They came stock on the 98-99 F bodys . 241's are a little better . I believe they came on 00-02 . 243's are the best of the 3 . 243's in stock , untouched form will add @ 20-25 RWHP over 806's and 241's.If so, the 862 has a tiny 1.9 intake valve. The 317 head has 2.0 valve and a larger intake runner cc, like the LS6. The 862 in a good bench make 220ish cfm, 317s as much as 257 or so. Just has a larger combustion chamber.I am beginning to find and spec all the parts I need to start the 6.0L LS swap for my 2002 Silverado. A significant key to the success of this build is the c...382 to the wheels just got a few more things done have to get it retuned will post the updatewhich stock ls head makes the most power? should i upgrade my stock 6.0l heads? do cathedral-port heads make more torque than a rec-port heads? what about th...118. Intake valve is 2" on the 241, exhaust valve is same size as the 862. If planning on 241 heads on, 05 LS2. I know the cam is .525 on both sides, but how much lift can the stock valve, Curious on what factory head would be better on my 2002 4.8. Factory has the 862 hea, There is a part number 12558060 Vortec cylinder head assembly sold by GMPP that is made from the casting num, 10. C.N.C Super Prepped Heads have fully CNC machined combustion chamber, Find many great new & used options and get the best deals for Ls1 Stainless Steel Valve 2.02" Intake, No 243s or 799 have the casting defect that I've heard, it was pr, An improved version of the stock LS7 cylinder heads, the LSX-, The 243's have bigger valves which do better on 4.0" and la, The 862 heads are a popular choice for those looking to increase the p, Jun 2011. Location. Clarksville, TN. Posts. 198. 862 heads fo, While this is the case, all of the work he put into doing that with , The 317s slightly larger runners and valves won', 243 04 up LS6 aluminum center bolt 5.7 ***These castings were also u, I am beginning to find and spec all the parts I need, oil catch can, Pacesetters LT Headers,3500 Stall, K&N CA, bmr , It's about 0.11" smaller than the stock at 2". Exhaust , Chevrolet LS rectangle port heads need at least 4.00.