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.Page LS1GTO Forums, HIGH PERFORMANCE Best LS2 243 Cylinder Heads upgrade, DRP GM LS1 LS2 Cathedral Port 243 Heads are a high quality product for a best These 243. Home; Home › ls1 with 243 heads and cam hp › ... Build 862 Vs 317 Heads (compression)?? LS1TECH Camaro And, 43% OFF.2752 posts · Joined 2011. #1 · Jun 25, 2012. Ok, just got my 243`s today. Not my first set of head porting, but it is my first LS set. Im pretty comfortable were im at with them right now. They are at the roughed stage, waiting on my roll kit. I spent $200 on some aluminum specific Snap On burs and boy to they work fantastic.Engine Technical. Engine Tech And Modification. LQ9 build cam suggestions. I just got my 4x4 T56 swap completed and now I'm planning a nice NA build. Through research I've found that the 243 heads and TBSS intake are a nice combo with CR around 11:1, and basically my whole setup hinges on the cam selection.In a comparison of the cammed 243 head and the cammed rectangle-port LS3 head, the LS3 torque peaks at 456 lb-ft (4,800 rpm) while the 243 head madeat leastthat much torque from 3,500 rpm all the ...Vehicle enthusiasts argue about 243 heads Vs. 799, as well as 243 heads Vs. 862 heads . However, if you desire improved horsepower with excellent power output, the 243-cylinder head is a perfect choice.Description. LS1 LS2 CATHEDRAL PORT - 243 CYLINDER HEADS. Sold as a Pair - Bare. Machined - ready for assembly. Suit the 5.7ltr and 6.0ltr. These Cylinder heads are a High-Performance replacement to the GM 243 heads. All factory mounting points with the Performance of the 243 port and chamber. You can use your existing valves & springs.40 posts · Joined 2018. #46 · Jan 20, 2020. Your 6.0 block is a 4.00 inch bore, you have to run a LS3 type head 5.3 and 4.8 have smaller bores. There are tons of heads out there yours probably came with the 799 castings like my 6.0 did.I know 243's are good but didn't know if 862's are any good when they're right in front of me. They won't flow as good as 243 but you'll have better compression vs 243. You can have them ported for a reasonable price and have a good valve job done on them to make them perform. They'll never be rock stars but they'll do fine with that cam.My car is an ls2 of course, but with stock injectors, fuel pump, and stock catback exhaust, and with stage 2 ported intake, tb,hpe 243 heads, megadeath cam, and slp underdrive pulley with lpe cai did 450 rwhp. The injectors were at 124 percent duty cycle, and we were losing fuel pressure above 6300 rpm.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.Patriot Performance 2033: My run a total 24 degrees of timing with 93 octane. These heads provide up to a 65 cfm improvement over stock OEM versions. The 59cc chambers (achieved by milling), will increase the compression on a stock LS1 from 10-1 to 11-1. Based on other modifications, gains of up to 40 rwhp can be expected.The cheapest way is to have your 243 heads ported, probably less than $1000 without labor and tuning. Patriot heads are about $1300+/-. Most other aftermarket heads will be over $2000 for the heads alone. You can get a whole L92/L76 swap kit for about $2100. To get a Ls2/Ls6 head to flow what a L92/Ls3 head flows will take a lot of work, and ...The intake and exhaust ports on the 243 heads are larger than those on the 799 heads, which allows for more air and fuel to enter the engine. This can result in higher horsepower and torque output. However, the smaller ports on the 799 heads can provide better velocity and airflow at lower RPMs, which can be beneficial for street-driven vehicles.link to camhttps://www.summitracing.com/parts/btc-trucknorrisLink to valve springs https://www.summitracing.com/parts/SUM-174002cam retainerhttps://www.summ...Fits 1997-2013 Cathedral Port LS Heads. Fits Casting Numbers 243 799 706 862 317 241 853 806. Set of 8 Exhaust Valves. Michigan Motorsports' stainless valves are a great upgrade for your factory LS cylinder heads. Made from high strength 21-4N Stainless Alloy, these one-piece forgings feature hard chrome plated stems and hardened tips for ...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.Aug 24, 2022 · 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 ...382 to the wheels just got a few more things done have to get it retuned will post the updateRPO L99 and LS3 cylinder heads are aluminum with 68cc combustion chambers, rectangle intake ports with 257cc runners, D-port exhaust with 87cc runners, 2.165˝ intake valves and 1.590˝ exhaust valves. These heads can be CNC-ported to improve on flow and milled for higher compression. These heads are almost the same, but the L99 heads used a ...Apr 2, 2020 · In a comparison of the cammed 243 head and the cammed rectangle-port LS3 head, the LS3 torque peaks at 456 lb-ft (4,800 rpm) while the 243 head madeat leastthat much torque from 3,500 rpm all the ...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...823 vs 243 heads The popular L6 243 heads have a smaller capacity (64cc), whereas the 823’s larger intake valve has a 70cc cylinder, promoting better overall flow within the combustion chamber. In addition, there’s some controversy among gearheads about whether the “swirl” ramp added to the 243 to improve fuel and air mix in the ...Price wise both companies are very close to each other. TEA Stage 2 Heads $1320 w/ 2.04/1.57 valves and dual springs. AI CNC Heads are $1245 w/ new stock valves and dual springs. It seems like the TEA has an obvious advantage in flow with the 2.04 intake valves but AI does not have any options for larger valves on their website.Fits 1997-2013 Cathedral Port LS Heads. Fits Casting Numbers 243 799 706 862 317 241 853 806. Set of 8 Exhaust Valves. Michigan Motorsports' stainless valves are a great upgrade for your factory LS cylinder heads. Made from high strength 21-4N Stainless Alloy, these one-piece forgings feature hard chrome plated stems and hardened tips for ...The 862 heads are inferior to the 706 heads in terms of compression, and they don’t also flow well like the 243 heads because it doesn’t have other competitive features; however, depending on your car’s needs and budget, the 862 cylinder heads might be a good port for you.The 243/799 heads made more power than the 317's in back to back N/A, and boosted, dyno pulls on the same motor. Sounds to me like you've already convinced yourself the 317 is the better head, so I'm not sure why your on here asking. Besides, from your post, headers are too small, so the head choice may be irrelevant.I've seen 400-500 for a heads with valves/seals/springs (most likely need to change them)/retainers/locks. 243 heads from c5 z06s have the sodium filled exhaust valves and hollow intake valves. Last edited by nullpointer; 08-17-2020 at 10:07 AM. They made millions of them. 799 is the same head.Aug 24, 2022 · 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 ...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. 8.12,557. The heads also bump the compression from 10:1 to 10.5:1 (stock for stock),,,,since they are milled (depending on how much) the compression should be even a tad higher than that. I'm sure the better exhaust side on those LS6 heads helped as well. Pretty interesting results for sure. 10-29-2010, 01:58 PM #5.After spending a very long time googling this, I've seen answers anywhere from 10.1:1 CR to 10.9:1 CR as it seems like people are calling lq9s (half a point high CR factory) lq4s and adding to the confusion. The engine is a 2005 lq4 6.0 with 317 (71 or 72 cc stock) heads and rated at a 9.4:1 CR. The 243/799 heads are 64 or 65 cc.ForceFed86. 2515 posts · Joined 2012. #4 · Jul 30, 2014. Sure they are. They just flow less. At .050 on the same flow bench a 243 flowed 251/176 VS a 862 at 218/163. One article I read showed a direct head swap with no other changes was worth 24ftlb. The CC in the 862 is 61cc VS the 243's 64cc I believe. So you need to factor that in as well.what i have learned is that running plain 243 unmilled heads 7.4 pushrod is fine. the 243 head with light weight valves requires you to run a shorter pushrod,or if the deck surface is milled. possibly a 7.35 length rod,but im not sure. would have to be measured for proper length. Like.Sep 1, 2017 · 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. ... 706/852/862 '99-up 4.8L-5.3L truck heads - 61 ...The 799 and 862 heads have their own pros and cons. While the 799 heads offer better flow and performance, the 862 heads offer better combustion chamber design and improved efficiency. Ultimately, the choice depends on the specific needs and goals of the engine. Pros of Using 862 Heads. Cons of Using 862 Heads.Go with the 862s for 3 reasons: Smaller combustion chamber will have a slightly higher compression ratio. If it's your first time porting you may as well fuck up the heads that have a lower resale value. differences in horsepower just aren't going to be a whole lot between the two once ported.Aug 1, 2023 · The 862 Cylinder Heads. Features and Specifications. In contrast to the 243 heads, the 862 cylinder heads are typically made of cast iron, which makes them heavier but also more durable. They have smaller ports compared to the 243 heads, which can limit airflow to some extent.An interesting finding is that in contrast; an LS1 head is 10-30 CFM below an LS6 head through out the range, stock and ported, except in the following instance when coupled with an LS6 manifold: Ported LS1: 166 / 211 / 229 / 244 / 257 / 269 / 277 / 283. + Port matched LS6 Intake Manifold. Note that the ported LS1 head with the LS6 manifold out ...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.The 862 heads are inferior to the 706 heads in terms of compression, and they don’t also flow well like the 243 heads because it doesn’t have other competitive features; however, depending on your car’s needs and …There is a part number 12558060 Vortec cylinder head assembly sold by GMPP that is made from the casting number 12529093 head. The info above about the L30 5.0L c/n 059 Vortec heads having the "same but smaller" ports is incorrect. The 059 head has a swirl vane cast into the port.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 …There is a part number 12558060 Vortec cylinder head assembly sold by GMPP that is made from the casting number 12529093 head. The info above about the L30 5.0L c/n 059 Vortec heads having the "same but smaller" ports is incorrect. The 059 head has a swirl vane cast into the port.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.Texas Speed & Performance is your one-stop shop for all LS and Gen 5 LT1 & LT4 performance parts and engines! We are among the largest LS and Gen 5 LT1/LT4-specific shops in the country, and we machine and assemble all of our engines, camshafts, and Precision Race Components cylinder heads in house! We also have a complete line of Texas Speed & Performance crankshafts, connecting rods, rocker ...Brawler LS6 Style CNC Ported Cylinder Heads w/ TSP .660" Spring Kit and Titanium Retainers $ 1,835.99. PRC LS3 Aftermarket 6-Bolt 260cc CNC Cylinder Heads $ 2,709.99. Precision Race Components Aftermarket LS3 As-Cast Cylinder Heads $ 2,101.19. Precision Race Components 2014 5.3L & 6.2L CNC Porting Service862 Heads Vs 706 Heads: A Brief Overview. Both 862 and 706 heads are popular choices for cylinder heads in engines. 862 Heads Vs 706 Head Comparison . Feature 862 Heads ... 243: Found on high-performance LS2, LS6, and LQ9 engines; 317: Found on 2001+ 6.0L truck engines (aluminum)The 862 heads are inferior to the 706 heads in terms of compression, and they don’t also flow well like the 243 heads because it doesn’t have other competitive features; however, depending on your car’s needs and budget, the 862 cylinder heads might be a good port for you.862 is a 5.3 liter head. Smaller combustion chamber (61.5CC), increased CR. 241 is a 5.7 liter head. Larger combustion chamber. Gains from a higher ration rocker arm (1.8 vs 1.7) are going to be minimal. Expect approximately 10 peak HP. IMO, if you have any plans of adding a aftermarket camshaft later down the road, pass on the 1.8 ratio rockers.The diameter of a .243 Winchester cartridge is 0.243 inches (6.1722 millimeters). The diameter of a .260 Remington cartridge is 0.264 inches (6.7056 millimeters). The .243 Winchester cartridge has a smaller diameter than the .260 Remington cartridge by 0.021 inches. The overall length of a cartridge determines how deep a bullet will sit in a case.The price difference for 799 an 241 heads is because the 799 is a twin to the 243 an have better ports an 64.54cc chambers where the 241/853s have not as large of a port an are 67cc..your 862 is actual the smallest chamber head being 62cc but their down side is smaller valve size an slightly less flow then 241/853 heads..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. It has a smaller 64.45cc chamber for more compression (10.5 CR on LS6), 210cc intake runners, and 75cc D-shaped exhaust ports.The 243 heads are, as far as i know, the best factory casting to go with based on the chamber design. Even though our stock heads flow very close to them(or the same), the 243 heads are supposed to have a quench pad in the design and offer better compression. The info i have lists the 243 heads at 65 cc so with the stock gasket you would be ...The 243/799 heads made more power than the 317's in back to back N/A, and boosted, dyno pulls on the same motor. Sounds to me like you've already convinced yourself the 317 is the better head, so I'm not sure why your on here asking. Besides, from your post, headers are too small, so the head choice may be irrelevant.The diameter of a .243 Winchester cartridge is 0.243 inches (6.1722 millimeters). The diameter of a .260 Remington cartridge is 0.264 inches (6.7056 millimeters). The .243 Winchester cartridge has a smaller diameter than the .260 Remington cartridge by 0.021 inches. The overall length of a cartridge determines how deep a bullet will sit in a case.check out this video were the guys from brian tooley racing swapped on a set of stock l83 (lt-based) heads onto a gen 4 5.3l ls. check out the power gains offered by the lt heads, custom cam and l86 intake on the ls. also tested an intake upgrade, comparing the l86 intake to the btr long runner trinity! share this; 0;PRC LS3, L92, & LSA CNC Cylinder Head Porting (Customer Supplied Castings) $ 899.99. Cometic Ford 5.0L Gen-1 Coyote / 5.2L VOODOO Modular V8 Intake Manifold Gasket Set $ 29.23. Cometic Ford 5.0L Gen-1 Coyote Modular V8 .027" MLS Cylinder Head Gasket, 94mm Bore, LHS $ 132.74. Military And Law Enforcement Discount . CONNECT WITH US.For the 862 heads, the intake valve size is 1.89 inches and the exhaust valve measures 1.55 inches. The 706 heads, however, feature an intake valve size of 2.00 inches and an exhaust valve size of 1.55 inches. In terms of port volumes, the 706 heads have larger intake ports.RPO L99 and LS3 cylinder heads are aluminum with 68cc combustion chambers, rectangle intake ports with 257cc runners, D-port exhaust with 87cc runners, 2.165˝ intake valves and 1.590˝ exhaust valves. These heads can be CNC-ported to improve on flow and milled for higher compression. These heads are almost the same, but the L99 heads used a ...