862 vs 799 heads. 7:1 compression ratio. Upgrade your LM4/LM7 engine performance with our quality CNC Ported 706/862 Cylinder head pair. Dec 24, 2020 · Look at valve diameter. 8L engines, so they are super plentiful in scrapyards. Oct 25, 2012 · However I'll bite, power should go to the 317 head just for the simple fact it should RPM better with the larger runners and better cylinder head flow. 0 did. 0L Gen III / Gen IV Cylinder Heads Assemblies. If those heads unmilled were to go onto the lq4 mentioned above with a stock 0. REMEMBER--just because the heads say '243' doesn't mean it has the lighter weight valves and upgraded valvetrain like the 243 heads that were on the Z06 Corvette. I just had a set of 317 heads milled down 35 thousands when I got my LQ4 block freshened up. 5" PTC converter. Maybe even some square port heads from a GEN 4 motor could work if you want a factory head. 0L * Specs : Combustion Chamber Volume: 64. I plan on going with the BTR truck Norris cam. 3 has 862 heads and I found a set of 799 heads on a 5. You will need the Dec 14, 2020 · Engine Mods - LS2 LQ4 PTV clearance question - I need some help, I am putting a set of 862 heads milled down 0. Some cylinder heads, however, have an architecture that reduces the engine’s ability to produce power. Only way to verify is to physically look for the notch on the 799 Heads and 862 Heads are different cylinder head options for LS engines. Heads I'm a little more unsure of. 0? the thing is I had them ported, polished and the 3 angle valve job on them and kind of would like to stay with them if they will do me any good. 5 CNC Cylinder Head Porting Service The PRC Stage 2. 317 and 243's flow the same. just guessing here. Find the better 243 or 799 heads. 55" ValvesNew Due to their ability to regulate the input and output of airflow into the cylinder heads, 862 heads are optimal for compression. The only exception being if you get a set of 243 heads off of a LS6 engine, those heads will have lightweight sodium filled valves but that won't make any difference in your power output. We sell sell these and the 4. 862/706 heads have higher velocity and better coefficient of discharge. 7L / 6. 0 to ~400ci (4. Mar 8, 2017 · Also have a set of 799's I could run, but I hate milling them and think the larger CC will kill the NA response/power. 045 gasket. Dec 7, 2009 · hey guys, what happens if I do a 5. 3L HEADS vs 241, 799/243 vs 317s. I have 317's currently which I know flow well but are much better for boost. Can I just throw the valves in and go what needs to be done to accomplish this. #lsxworld #lsxnation Oct 21, 2019 · There are tons of heads out there yours probably came with the 799 castings like my 6. 3lsx Build Parts #lsxworld #5. Aug 7, 2020 · Hey all I have an lq4 I want to swap into my obs but I want to get some 243 heads milled to 62cc with I was told maybe a . 3L, LS1, LS6, LS2, LQ4, LQ9). ” However, their thin cross-section allows for a high-velocity and smaller-volume runner design with excellent flow. Throwing some 862/706 heads on a 6. 3 while the 706 heads are from a 2005. My plan is to rebuild the spare block from the inside out with all new bearings, BTR "Torque" cam, Weiand aluminum intake, and then port/polish the heads. 0 Iron center bolt heads 317 01 and up LQ4 and LQ9 6. It significantly contributes to the engine’s exceptional performance. Every thing I've read says the 862 (on the L33) Dec 18, 2024 · Heads and compression on LQ4 So I have an LQ4 with a sloppy stage 2 cam, a GT45 turbo, and 317 heads. Typical gains are 10-20rwhp. Dec 13, 2015 · The price difference for 799 an 241 heads is because the 799 is a twin to the 243 an have better ports an 64. Jul 17, 2019 · Hello All, I recently heard that the 862 heads outflow anything else out there for the LS platform. At LS Performance Racing we understand that the Gen3 LM7 5. Running flat tops and compression is in the 10:1 range. 8L 5. Im wondering if by using 799 heads and an LS9 head gasket, will my compression ration be too high for 93 pump gas and boost? Ive been running it on 93 and about 8-9psi for months now and havent had any problems. Otherwise running stock 706 heads and stock truck intake with DBW throttle body. The 706 heads are the same as the 862 heads. 3 block with 243 heads on it for $300. 8 and 5. Holdener testing). 0L, then the 799 vs LS3 Aug 18, 2011 · 6. 8/5. Color the port, accurately secure/lightly scribe the reference. 0 aluminum center bolt heads Even more detailed info: 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? WHAT ARE TH May 7, 2019 · I’m having a hard time finding a set of 243 or 799 heads, so I was considering having my 317’s milled approx. Sep 1, 2017 · History of the LS Engine and Cylinder Head Casting Number Spotter’s Guide: LS1, LS6, LS2, LS3, LS4, L99, LS7, LSA, LS9, LQ9, LQ4, L92, L94 LS Everything: An in-depth look at the LS engine series Mar 13, 2018 · We find out which factory LS head works best under boost in this back-to-back test of the 706 heads vs. 0L AND WANTED TO MAKE MORE TOWING TORQUE, WOULD YOU PICK 706 HEADS OR 799 HEADS? WHICH ONE WOULD MAKE THE MOST HP, TOQ OR AVERAGE POWER IN A USABLE RANGE? WHAT ABOUT COST? LET'S Sep 4, 2021 · While 862 heads are sand cast, 706 heads are semi-permanent mold. So far I've read the stock 706 heads. Nov 10, 2023 · 799 Heads and 862 Heads are different cylinder head options for LS engines. Visual Aid. I can get a set of 706 heads locally for $100 and WHICH STOCK LS HEAD MAKES THE MOST POWER? SHOULD I UPGRADE MY STOCK 6. Feb 13, 2020 · The 706 Vortec heads are even slightly superior to the commonly found 862 heads. Feb 21, 2023 · Cylinder heads are one of the most important parts when it comes to the performance of any vehicle engine. 9-to-1, but they cost more than 706 / 862. 9:1 GM's castings (and other manufacturers for that matter) can have production variances that can cause specs to be off. 3Truck heads ***reportedly came on a few corvette's too*** These are basically 243 Heads 873 99-00 LQ4 6. 862 heads. LET'S TALK TECH, ANYONE EVER SEE A SET OF STOCK 243 HEADS FLOW 270+ CFM? WE COMPARED 243 HEADS TO 862 HEADS, PORTED, CHAMBER WORK & BIG VALVE. 0L, LS1 and High Performance LS Motors. 3L Cylinder Heads 706 Assembly w/Rocker Arms SET OF 2 LS LR4 LM7 LM4 862 (Renewed): Cylinder Heads - Amazon. Let’s examine the 799 vs 243 heads and see why WHAT IS THE MAX POWER I CAN MAKE WITH 317 LS HEADS? HOW WELL DO 317 HEADS WORK ON A 5. 243 would have to be milled from my understanding just to get back to factory type compression. the stock pistons were at a true zero deck and the 799 heads we got were measured at 65cc's, which brought it to 8. I have a spare LS short-block that is also an LM7 (I think) with 862 heads and no intake on it. Vehicle enthusiasts argue about 243 heads Vs. Which heads are best for my ls1 862 or 853? Putting a new ls1 motor in the Camaro. But if its a full rebuild I would do flat tops and mill the 317's then run a Gen IV cathedral intake or buy a holley truck intake and 90mm TB. 040 head gasket to bump up the compression. If my intent is stroke this 6. 32 S480 with a pretty tight (14 stator) 9. 8L and 5. 3 to 6. mainly cam and other smaller things. I am wondering in terms of flow,compression,ect I will be using them on a 5. It all comes down to valve size from what I know. Tune in every week for Muscle Monday and be sure to SUBSCRIBE to our channel! Jan 5, 2015 · 862's were on early 4. Feb 11, 2023 · I got an estimate on rebuilding the heads, 3 angle grind, new guides, $700. 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. 0) heads and compression at 9. Jun 13, 2023 · 706 Vs. I have seen stock engines with 2 different casting number heads on them. FACTORY LS3 vs TFS 225 GEN X CATH HEADS! WHAT WORKS BEST ON A 6. 3L NNBS motors either came with the 799 or 243 heads and flat top pistons. 799 heads??? big difference or no? Jump to Latest 27K views 2 replies 2 participants last post by parks450 Oct 14, 2010 parks450 Discussion starter Oct 4, 2012 · 799 vs 862 heads which is better? I have a 99 5. Nov 15, 2022 · This is a SET OF 2 Remanufactured OE Stock LS2, LS6, 4. Some of the propaganda from Chevy states that the heads on the L33 are LS6 units with bigger valves and bigger ports. We also offer other Valve Springs options as well. The Dec 22, 2017 · We test a number of stock LS heads and came out with some very surprising horsepower numbers that will turn the internet speculators on their head. I know 243 and 823 are good ones but trying to find them can be difficult. 3/4. I just purchased some stock remanufactured 862 heads and while inspecting them I found this deep cut. A relatively high compression ratio is great for a car’s internal engine combustion process. 5. 862 99 and up 4. 3L and 4. 706 heads - L33 engine in son's turbo truck has a cracked block. 00"/1. What have you heard about 799 heads? An in-depth discussion on the features, benefits and common problems of it is essential for both mechanics and car owners. 3L LS engine. 706 5. If you need a complex cylinder head with enough power to boost your vehicle's performance and efficiency, go for the 862 cylinder head. 3l #lsxnation #gbody #gbodynation Ported 862 Heads VS Stock 799 Heads. 706 heads on the 5. doing a “mild” build in it. The 799 and 862 heads have different casting Read Jul 31, 2020 · The Gen III have 862/706 Gen III heads, and the Gen IV have 243/799 heads. 5-61. 3L? SHOULD I SWAP TO 317 HEADS ON MY 4. Apr 26, 2018 · From the best headers & intake to cam swaps & beyond, here's a step-by-step performance upgrade guide for the L33 5. I plan on putting this into my 69 camaro after a freshen up I wanted to share a good place to start your port work. Think they flowed like 308 @700 lift. What is the difference between the 806 and 862. WHICH HEADMAKES MORE? We compared the four most popular stock LS heads in a back to back shootout. I will be port and polishing then and maybe mill and larger valves. I know 243's are good but didn't know if Sep 24, 2015 · Cathedral port cylinder heads have been mistakenly dismissed by many in LS-series circles for being “old-tech. The reason is that the 706 heads are SPM (semi-permanent mold) made, while the 862 heads are sand-cast. However, porting is expensive; therefore, casting 706 heads in stock form is the best option. 0. 06cc chamber size, which lowers compression when used on a LS1/6 engine. May 24, 2020 · FULL RESULTS-FACTORY LS HEAD SHOOTOUT, 6. Dyno tests have proven that comparable aftermarket cathedral port heads […] Feb 23, 2021 · Which Stock LS Head Is Best For Building A Boosted Turbo LS Combo? 317, 799, 706, 241, 243, or 862? Feb 23, 2021 Chad Reynolds 1320 Engine Tech, 1320 Spotlight, Apex Engine Tech, Apex Spotlight, XL Engine Tech, XL Spotlight Comments Off on Which Stock LS Head Is Best For Building A Boosted Turbo LS Combo? 317, 799, 706, 241, 243, or 862? Nov 18, 2022 · 862 Vs. * Part # : 799 also fits 243 casting * Description : Stock LS Series 4. 4:1 CR. 3 that's going in my 02 silverado that currently has a 4. 3 LS could be had with one of four cylinder heads: 706 heads, 862 heads, 799 heads, or 243 heads. 3 Heads on a 6. Most calculations or other people's measurements see 10. 5:1 or stock 317(6. These valves are designed to be a direct drop Nov 18, 2013 · Just got this slightly used Ls chevy stroker 408. How much would you notice the 3* or whatever lower WOT timing? Big deal. What LS engine came with 706 heads? These heads came on hundreds of thousands of 1999 and up GM 5. You can get a pair of stock 243/799 heads for around $500. 55" Valves Mar 16, 2018 · Even the 799/243 heads on the aluminum 5. However, some cylinder heads are built to minimize the engine's horsepower. The 862/706 heads have smaller combustion chambers than the Gen IV, raising the compression ratio when swapped directly. General Motors produced 862 engines with a GEN-III Cylinder head 10. Oct 13, 2010 · 862 vs. 243 and 799 heads are the same head, just some slight differences - valve stems (hallow vs solid) and where they were cast. 8 had the casting notch. 3L and 6. 0L versions). New comments cannot be posted and votes cannot be cast. 5 CNC Porting Service is the perfect solution for customers looking to maximize the performance of their cathedral-port LS cylinder heads (4. 7L and 6. Obviously it needs a lot of work to verify any hidden damage but is it worth it? Run of the mill gm 706 cathedral port head with plenty of miles. Since I don't have funds for a The last LM7 i built was a budget boost build. Again too many unknown variables. Any 799 or 243 head found on a truck had the regular valvetrain. 5-10. Nov 24, 2021 · Cylinder heads are the essential building blocks of an engine, and they play a vital role in the efficient operation of a vehicle. 0L REC PORT VS CATH PORT HEAD TEST. 617 lift), 113 LSA) in but I see some others online IF YOU HAD A 6. Is it worth doing anything to the heads with the stock cam. The cylinder head’s compression ratio leads to increased in-cylinder pressure, a higher rate of heat discharge, and quick ignition. 862 Heads The 706 model is made to be superior to the common 862. 0 LQ9. 5:1 This article will explain all you need to know about the 799 heads. is it worth trying to port and polish if so are there any recommendations for it? Oct 2, 2017 · The engine is a 2005 lq4 6. But I can pick up some cheap 862 heads locally. The type of cylinder mounted on an engine plays a significant role in determining its performance. ARE THE 706/862 HEADS BETTER THAN THE 799/243 HEADS? DO THE REC-PORT LY6/LS3 HEADS MAKE MORE POWER THAN THE 243/799 HEADS? 6. If you'd have to get some heads for a stock ish LQ9, I'd go with reworked 799s with bigger valves. However, if you desire improved horsepower with excellent power output, the 243-cylinder head is a perfect choice. That's why we try to give you the best information possible, so you can get the best setup possible for your vehicle application. The 243/799 heads are 64 or 65 cc. Dec 28, 2011 · any difference,good,bad or indiffrent? the 862 heads are off of a 2000 5. Get the 60cc heads and enjoy the compression boost. Seller claims that it is completely normal for 862 heads and will not affect anything. 0 with 243 heads, some are 799 but the same. Hopefully someone with more knowledge and experience will chime in. I am tapped out financially because I went with better springs and upgraded push rods, this way I only have the cam to deal with at a later date , probably a year or so later. 0 Elgin 1841p cam single plane intake which heads will be better 862 heads or 823 heads looking for some feedback Feb 27, 2015 · If I get those heads, I will be swapping out the intake valves for the stock LS1 size. 1 and the 243/799 heads between 64. It's also not only because the chamber size and compression ratio either. It just so happens we have an aluminum ls1 and a steel ls1 (my dad got a really good deal from a friend). Jan 18, 2022 · 2. 0 with 317 (71 or 72 cc stock) heads and rated at a 9. Would the stock 243 heads work better on it than the 862 heads? Obviously they need to go to the machine shop to be looked over but without any Nov 2, 2011 · 243 on a 6. the 317 heads. 00 inches Exhaust Valve Diameter: 1. The semi-permanent mold (SPM) method is a consistent process. On the contrary, some cylinder heads boost the engine's performance due to their unique architecture Aug 3, 2022 · 823 vs 799 heads 799 heads have a cathedral port shape (with a point at one end) which delivers improved performance down low, but for top end sportiness, stick with 823s. I would like to put a Comp cam 54-459-11 (231/239 with . I was orginally thinking of porting the 862 which are 5. 3. 0L? HOW WELL TO PO LS1 LS3 11 Degree LS7 LSA 243 799 862 706 317 CNC ported Shaft Rocker Arms LQ4 with 317 heads 9. 8L / 5. All that said … That’s my back up motor for when my LT1 stroker puts me Parts - Cylinder Head Parts & Services - GMKatech ASSEMBLED CNC Porting Bundle LS1/Truck 862, 706 Cylinder Heads (PAIR) With NEW 2. Talking about chevy engines, we have three options – 317, 706, and 862 heads. 3) heads and compression at 10. What are your feelings on that?. Some casting numbers can be setup for 2 different bore sizes. 0 truck heads (casting #317) are popular heads with the forced induction crowd, as they are basically the same as 243 heads, but with larger 71. For a street car, this design means excellent throttle response, torque and average power. 8/5 Wallace Racing BACK to Calculators Todays date is 9/19/2025 Enter the required information into the boxes and click results! Tip! This Calculator is designed to tell you how much you need to mill your heads to achieve the specific Compression Ratio you are looking for. 3 Truck heads 706 99 and up 4. But then 10. Fits 243, 799, 706, 862, 317, and other cathedral port heads on LS1, LS2, LS6 Jul 16, 2018 · Just picked up an 05 Escalade 6. Cylinder heads play a crucial role in the engine's performance, as they control the flow of air and fuel into the combustion chamber and the expulsion of exhaust gases. GM 243, 799, & 317 LS2/LS6 Options: Performance Rebuild Package Our Performance Rebuild option includes our high end CNC'd valve jobs, precision valve grinding, milling to any chamber volume, cleaning, inspection, and professional assembly. I just pulled the heads off a 4th Gen 5. Only got one reply. 0L? Having already compared the 706 to the 799 heads on a 5. I could be very wrong but I'm going to have a set of 862 worked and see because they are usually cheaper. With upgraded 2. com FREE DELIVERY possible on eligible purchases Jan 28, 2020 · I’ve had some emails and messages, on the SierraC3TV Facebook page, making arguments against using 706 heads on my 6. 57” stainless steel valves included, this service is designed for those who want increased flow and horsepower potential without Feb 10, 2022 · Curious on what factory head would be better on my 2002 4. 68:1 for 706 heads on a LQ4 Jan 5, 2013 · I'm wanting to do valve upgrade on my 862 heads, 2" valves intake and have them milled n hand ported an polished. I’m building a lq4 6. If you Do not know your current Compression Ratio, go to the Compression Ratio Calculator to figure it. 85cc on my Lq4 block so with stock dished pistons I expect about 10. In this episode, I give my reasons why I’m using them and discuss the Jun 12, 2023 · A car’s cylinder head is an excellent part. 799 Heads Vs 862 Heads: Side By Side Comparison 799 Heads and 862 Heads are different cylinder head options for LS engines. 7L, 6. 550" Stock Replacement LS Exhaust Valves Fits 1997-2013 Cathedral Port LS Heads Fits Casting Numbers 243 799 706 862 317 241 853 806 Choose Single or Set of 8 Exhaust Valves Michigan Motorsports' standard replacement valves are an affordable option to freshen up your stock or mild performance LS engine. stock 6. 576" 113+2. 3L engine, I discovered that the 799 made the most flow, but it couldn’t translate into power. 5 comp with 66cc patriot heads on it now with stage 3 port job. 3 I own and it had a 799 on one side and a 243 on the other. Its got a callies crank 600 lift cam. 3 in the Silverado lose 12lb ft of torque over the 706/862 casting in a back to back test. 799 Heads When testing these two types: 799 vs. The motor was equipped with a healthy Comp cam and run with the Dorman LS2 intake on the Apr 16, 2013 · I've read that 862 ported and milled will do wonders on the 4. Nov 8, 2022 · Buy GM REMANUFACTURED 4. 052" head gasket, what SHOULD the compression ratio be? 4. Is this true? I'm currently running the 799 stock on my 5. or should I use the ones the 6. 0 aluminum center bolt heads 035 01 - 04 LQ9 6. The 862's will probably generate more torque down low due to compression and velocity with smaller runners and smaller valves. Looking to possibly do a head swap and cam. VERY SERIOUSLY CONSIDER 91 octane, especially if working or playing HARD 3. 3? Sorry, this post was deleted by the person who originally posted it. Factory has the 862 heads. Personally on a 4" bore I'd rather have rectangle port heads and live with the lower compression - in that case, the better heads would more than offset the loss of static CR. Cylinder heads are the essential component of a vehicle and they determine the efficiency Hand Ported 862 vs Hand Ported 799 heads on L33 5. At LS Performance Racing we understand that there are a lot of newcomers eager for Knowledge. Trying to spool an T6 1. 706 Heads: which is the best cylinder head for your car? Let’s find out! 862 heads and 706 heads are both cylinder heads that make up the top of the combustion chamber. Last edited by 1slowbusa; 08-18-2011 at 03:09 PM. 3L, 5. 015 to 58. 0 stock 862(5. Any input? Nov 27, 2006 · Like I said in my other post here the 799/243 heads are the same. Nov 5, 2017 · had my heads replaced with some 799 heads over a year ago due to the castech crack and i spent over $1200 in parts alone and another $1000 in labor for a shop to put it all on since i couldn't do it all at home. 0L HEADS? DO CATHEDRAL-PORT HEADS MAKE MORE TORQUE THAN A REC-PORT HEADS? WHAT ABOUT THE CHANGE IN STATIC COMPRESSION? WHICH Oct 20, 2017 · 243/799 heads are hard to beat for how well they perform for a stock head and would bump the compression over a 317's. 7/6L's. The notch disappears sometime in 2001 but nobody is sure. Although the SPM approach is more reliable, porting 862 heads eliminates their distinction. Some early LS heads from 98-01, both the 853/806 LS1 and the 706/862 5. 3L motors) and a set of 243/799 heads (used on both the small-bore motors and larger 5. Though multiple cylinder head options are available in t Dec 25, 2017 · LS1TECH - Camaro and Firebird Forum Discussion LS1-LS2-LS3-LS6-LS7 PERFORMANCE Generation III Internal Engine 706 Heads Rule?! (706 vs 241 vs 317 vs 799/243) Generation III Internal Engine 1997-2006 LS1 | LS6 Sponsored by: 706 Heads Rule?! (706 vs 241 vs 317 vs 799/243) Reply Subscribe Thread Tools Search this Thread 799 Heads Vs 862 Heads: Side By Side Comparison 799 Heads and 862 Heads are different cylinder head options for LS engines. 0 LSx Swaps Jun 21, 2012 · cammed 6. We’ll run through each iteration below, providing chamber and valve sizing, and their pros and cons to help you decide what are the best LS heads for your build. 051" or 0. Jul 10, 2022 · Also, the port velocity on the 706/862 head is much better than the 799/243, which will help you with the small bore of the 5. 0L WHO WINS? Check out this comparison between the 706, 799, LY6 and TFS 225 heads on a cammed 6. Oct 27, 2001 · @PD939C1 That post was only a joke My point was do not use 862 and 706 heads on a 6. 3 Truck heads 799 05 and up 4. Goal 375-425hp at the crankshaft prior to the Turd-Bo turbo install! 👍862 castings 20022. Feb 12, 2025 · The 317 and 243 basically flow the same but you gain CR due to chamber size vs milling. A right cylinder head ensures the engine’s performance and longevity, so it’s important to select the appropriate head for your car. 3 in a savannah van and I was wondering what heads were better with a small cam and 75 hp shot of nitrous Reply With Quote 10-04-2012 04:07 PM #2 jansen Mar 6, 2025 · This list included stock 706/862 heads (used on the small-bore 4. 5:1 compression ratio with smaller combustion chamber with a more responsive performance curve. Our high end machine work applied to GM's best I flow a stock 706, 862, and 317 LS Head and share the numbers. Feb 3, 2009 · INTERNAL ENGINE MODIFICATIONS - 862 vs. 862 LS Heads make the top choice when it comes to high-performing cylinder heads. 8-5. 3 litre heads and then enlarging the intake valves to 2". 650" lift Valve springs upgrade. But, it is something about which many people are not adequately informed. Here is a dyno graph from Richard holdener. I will measure when the time comes but do you think I would have issues? Select Your Vehicle Home → Heads Heads Aftermarket Heads CNC Porting Service Sort By: Page Size: Quick tips for porting and polishing any LS heads My IG: 13b_dorito Here is some useful links for tools that you need to get this job done and that you will Here's a set of our Stage 2 ported LS 243/799 heads that's setup with BTR Dual . This is an advantage when analyzing 799 Vs. 799, as well as 243 heads Vs. 8 and the 5. But if buying a 799/243 head, might as well buy LS3 units since 243 if used would need rebuilt anyway. 10. Got a long list of things I'm about to do on my truck, just wanted to ask to see if it Jan 14, 2018 · Generation III Internal Engine - 862 heads any good? - My friend has a pair of 862 heads in good shape for a good price. Upgrade your LS engine with 1. 243 / 799 pope hat heads should keep the scr under 10. You should look for 317 or 243/799 heads with the emphasis on the later for NA builds, if going boost then the 853's. Conversely, certain cylinder heads have the best architecture and produce excellent power output with more horsepower. The 862s are functional equivalents from the same years and were never suspect for cracks. 226cc Full CNC Porting Package The go-to head for 450-500rwhp 5. I want to run a 227/234 btr cam with 614"/. Jun 3, 2022 · Check out Our Other Articles: 799 Heads & Its Application Are 862 Heads a Better Choice? Why Chevy 706 Heads LS Make a Great Choice? 13 Step Process for Remanufacturing Cylinder Heads Ford V10 Cylinder Head Replacement Cylinder Heads for the Chevrolet 350 - What You Need to Know Vortec Engine History and Cylinder Heads Oct 7, 2024 · About this item Michigan Motorsports 1. 317's and 241's are the worst factor LS heads. . Bought 862 heads but have a deep cut Hey. 3L, 6. 0, which is a little . The 862 and 243 heads excel in different areas, but choosing the wrong one might leave your build underpowered Oct 5, 2019 · To get the best bang for your buck gen 3 lq4 + 862 Heads will give you a 10. 8 daily driver. thanks guys! Jun 24, 2018 · Showing the port work on my 862’s setup for a small 4. 3L engine is a very common engine that people like to do cylinder heads and camshaft swaps with and one of the Mar 8, 2018 · We find out which factory LS head works best under boost in this back-to-back test of the 706 heads vs. 8L , 5. 45cc Intake Port Volume: 210cc Exhaust Port Volume: 75cc Intake Valve Diameter: 2. Than Nov 21, 2023 · The Ultimate Guide to Choosing, Installing, and Tuning GM 862 LS Heads for Big Power Gains on 5. Feb 6, 2019 · Just curious how much any of you have milled your heads and did you have any intake sealing issues? I'm trying to decide if it's really worth milling for Tried this question on another forum and was hoping a few replies to confirm. 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 PRC Stage 2. 55 inches * Note Katech CNC Porting LS1/Truck 862, 706 Cylinder Heads (PAIR) Katech CNC Porting LS2/LS6/Truck 243, 799, 317, 035 Cylinder Heads (PAIR) Katech CNC Porting LS3/L92/L99/L76 364, 5364 Cylinder Heads (PAIR) Katech CNC Porting LS3/L92/L99/L76 821, 823, 716 Cylinder Heads (PAIR) Katech CNC Porting LS7 8452 or LSX-LS7 Cylinder Heads (PAIR) General consensus is the 706/862's flow well enough to support over 450hp NA. I do not plan on Spraying the Jul 16, 2007 · C5 Tech - Difference between 241, 243 and 853 heads?? - Whats the difference? I have 853's, which heads are good for porting and which flow the best? Thanks Product Description Michigan Motorsports 1. The OE LS7 cylinder head is equipped with a straight shape valve spring while all other OE LS cylinder heads are equipped with Beehive-Shape springs. Aug 7, 2023 · When it comes to choosing the right cylinder head for your car, you might find yourself in a dilemma between 862 and 706 heads. 3L with aluminum block. Which heads would be best 862 or 853 Archived post. This week I'm getting 799 ported head GM CBM heads installed (same as 243 ported heads). 0 is a well worn subject for the bump in compression, but I do see some people decrying the lackluster flow compared to 243/799s. Apr 15, 2022 · The 799 LS heads are some of the most popular heads used in LS engines. The lower coils are round and taper up to a smaller diameter resembling a Beehive. I’ve been offered a 5. 4 (Low CR for 1840P?) LQ4 with 799 heads 10. 0 youre looking at close to the same compression as an ls2 since ls2's are 6. Cylinder heads play a crucial role in the engine’s performance, as they control the flow of air and fuel into the combustion chamber and the expulsion of exhaust gases. We ran the 706/862 Previously, we compared the stock 706/862 heads to the 799/243 heads on a cammed 5. 54cc chambers where the 241/853s have not as large of a port an are 67cc. 900) and use it as a tow/haul/daily driver, will the 862 heads work well for these purposes May 11, 2013 · 5. 3 correct. On the other hand, 706 and 862 heads are almost identical. 0 with 243's youre going from 310 or what ever the stock numbers are plus 30 maybe 40. I am thinking of maybe getting some L92 heads, with an LS3 intake. In this case, the 706 did a better job. This is my first time messing with an ls. The 317 heads are equipped with superior ports but a lesser horsepower. 550" stainless exhaust valves from Michigan Motorsports. 550" Stock Replacement LS Exhaust Valves Fits 1997-2013 Cathedral Port LS Heads. 3L OR 6. We would like to show you a description here but the site won’t allow us. add a nice cam for good torque to compliment the truck intake (depending on vehicle it will be in) and you're looking Aug 31, 2020 · Flow is meh even when ported. Jul 24, 2024 · The 5. Is this cut Normal and wouldn't this be a weak point for cracking? Jan 16, 2018 · 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. Also Fits Casting Numbers 243 799 706 862 317 241 853 806 Choose Single or Set of 8 Exhaust Valves Michigan Motorsports' standard replacement valves are an affordable option to freshen up your stock or mild performance LS engine. 0L? What is the bes Oct 14, 2019 · CGT wrote: ↑ Mon Oct 14, 2019 1:18 pm I think the 706 and 862 castings have a lot of potential within the OE cathedral castings, yet they get passed over frequently in favor of 243 and 799. 15 (PTV Clearance with larger cam?) LQ4 with 862 heads 10. Jan 1, 2025 · Deciding on the right cylinder heads can dramatically affect your engine’s performance, budget, and overall reliability. Jan 21, 2022 · All LS cylinder heads have performance potential, but as with any aspect of engine building, the end goal determines the starting point. 3 Help. 0 block and some 862 heads for a decent price. Curious of y’all’s experience with heads like this coming back to life. More below Jul 9, 2012 · What would be my best options for heads on a built LQ4? I plan on running a GMPP Hot Cam, or potentially some other type of large cam and I may stick with the TB injection, rather than carb it. What makes the decision so hard is the fact that for the price of having the seats cut and a valve job, I could buy a pair of 243 heads, and I know the 243's have more flow potential than the 862, but they won't provide the high compression. The 799 and 862 heads have different casting Read completely tore down a early L59 and in process of rebuilding it. 02”/1. Oct 15, 2021 · With a plethora of automotive components available in the market, you may have a hard time knowing which cylinder heads are right for your vehicle. 46 1840P Cam LQ4 with decked 317 ??? On an unrelated note, has anyone tried the no name ebay SS2 cams? I am wondering if they are just white box Elgins or if they are horrible quality. Parts - Cylinder Head Parts & Services - GM - Gen 3/4 LS - LS Cylinder Head ServicesKatech CNC Porting Bundle LS1/Truck 241, 806, 853 Cylinder Heads (PAIR) With NEW 2. 8 build. 3L test motor. 706 Heads vs 317 Heads Due to their better ports, 317 heads are Dec 24, 2017 · We test a number of stock LS heads and came out with some very surprising horsepower numbers that will turn the Internet speculators on their head. 0 have?? cause i dont think I can afford the heads job again right now. Dec 2, 2019 · I compared a set of stock 799/243 cathedral-port heads vs the 823 LY6 rec-port heads on an LY6 short lbock. A good street cam and TBSS intake should get you close to 450, but you're going to be hard-pressed to hit 500 with a NA 5. 040 x 3. There's no debate, it's been proven the 862/706 heads will make more power than the 317's. For that price, is there a better head that i can swap in that will give me better performance? Best CNC Ported 862/706 heads for sale online at Alliedmotorparts. There was much uproar among 799/243 head enthusiasts. Both are almost identical in appearance, but the differences lie within their compression ratio and the range of vehicles suitable for the 862 vs 706 Heads The Chevy 706 LS Heads are superior to the most popular 862 heads, sand cast, and produced using semi-permanent molds (SPM). 8L/5. Mar 4, 2019 · He breaks down some of the major differences between various LS Cylinder Heads. The 243 heads and 799 heads are the same. which heads should I get professionally hand ported 862 or 853. i know these heads are aluminum and i have read that they’re pretty soft. Nov 9, 2009 · All 5. we have measured the 706/862 heads between 60. 5-65. Porting theory on raising the roof and how far & straightening the walls Jan 9, 2022 · It has been proven that stock 799 heads do not hinder flow all the way up to 5000rpm on a 6. 8L, 5. (see R. 8. They offer excellent performance & durability and are suitable for many different applications. 0 and install the 862's to the 6. some people port and polish some people clean them and leave as is from what ive read. 706 Vs. now I'm considering just haveing the 853s done any thought and feedback is appreciated. 3L Truck 862 and 706 Head castings While the 706 Heads are a SPM = Semi Permanent-mold And considerd to be a more consistant head casting then the 862 wich are Sand cast, Once ported There Is no difference. Jun 9, 2016 · The heads with the casting flaw were the 706 castings made by castech from 2000-2005. And according to our Econ 101 class, a large supply generally equates to a lower price. 00/ Dec 11, 2020 · What are the best set of factory heads for a n/a 4. Came across an opportunity to grab a 6. 25-30 thousandths and going with an . I don't see a big gain going to a ported 243 when you factor the loss of compression vs a 799. 6:1 with rectangle ports would only be even better. L33 is a higher output 5. If that. The 706/862 respond very well to a light runner cleanup and a good multi angle valve cut. So, they need to withstand extremely high temperatures and immense pressure. Just wanna know if I'll benifit from them at all from stock ls1 heads. I have a mild cam 218/227 long tubes and a lid plan on doing heads and a LS6 intake. 6:1 with that cam (or any cam) would be fine. ibp mfaiuwx vobjaj gngohb iewsff iedrbz brd zqmhzho mrdmw jhrdvh