forthman. 654 posts · Joined 2003. #2 · Mar 16, 2006. The old 69-70 351w heads have bigger valves and intake runner. Otherwise the 302 and 351w heads are the same. E7TE castings are albout as good as they get. The 289 heads do offer smaller combustion chambers but also smaller intake runners. I ran 302 E7TE's ported and milled so they had ...Is 862 Heads Any Good? If you are asking, “Are 862 heads any good?” The 862 heads are pretty good because they can deliver better compression after a porting job. However, …ddawson. 15570 posts · Joined 2004. #4 · Sep 29, 2008. The 317 is a 243 but with a larger CC. I have the 317 on my car with 70CC. 1969 Corvette, 427 Convertible. 496CI Edelbrock Heads, Quickfuel Carb, LS6 Intake. Straub Technologies 229/235 .590/.559 107, Hedman Headers, Magnaflow Exhaust. Speed Direct Rack and Pinion, Semi Coilovers ...link to camhttps://www.summitracing.com/parts/btc-trucknorrisLink to valve springs https://www.summitracing.com/parts/SUM-174002cam retainerhttps://www.summ...I've had some emails and messages, on the SierraC3TV Facebook page, making arguments against using 706 heads on my 6.0. In this episode, I give my reasons wh...5475 posts · Joined 2005. #4 · Jan 19, 2015. Put in stock 4.8 pistons, they're already flat tops and its what the L33 5.3 is with 243 heads. Stock compression on them is 9.9:1, it'll be a little higher with stock 5.3 heads but if it were me I'd go ahead and do some milled 243's with some bowl work. 2001 GMC Sierra RCSB.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 ...FULL RESULTS-BIG LS3 HEAD TEST, AIRFLOW AND POWER! STOCK LS3 v PORTED STOCK v AFTER MARKET. Check out the results of our big LS3 head comparison. We ran the ...706 vs 862 heads - Thoughts on port/polish? My current LS is a stock LM7 out of a '05 Silverado with about 130k'ish miles on it (112k when pulled; about 20k on the swap). Only major change is the Holley Mid-Mount kit on the front and some generic block-hugger headers. Otherwise running stock 706 heads and stock truck intake with DBW throttle body.I wonder if the Edelbrock head was an LS1 or a 5.3L specific head. The bore difference of the LS6 to the 5.3 liter motors is 99mm vs 96.01. 3mm diameter is only 1.5mm smaller from the wall to the valve. I know it will shorud but the test showed it worked. The engine ran on an engine dyno and ran well.Feb 9, 2022 · Factory has the 862 heads. 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 machine shop to be looked over but without any alterations to the stock form, which is the better head? Engine is stock other than cold air intake.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 ...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. CMIIW: I've been told there is no major difference between the 706 and 862 heads once you work them over. So I'd be okay having the 862's ported/polished/rebuilt rather than my current 706's.Run with the 317 heads, the modified 5.3L produced 448 hp at 6,800 rpm and 398 lb-ft of torque at 5,000 rpm. After installation of the 706 heads, the power jumped to 468 hp at 6,800 rpm and 413 lb ...The first has to do with port shape. The LS6 and the later LQ9-LQ4 heads used reshaped intake ports and D-shaped -- as opposed to oval-shaped -- exhaust ports for better flow: 200 cfm intake and 70 cfm exhaust for the 241's, and 210 intake and 75 cfm for the 243's. The second major difference is that the LS6 heads used hollow, sodium-filled ...the LS6 243 heads have the hollow Intake and Sodium filled exhaust valves for higher RPM use. 7000 rpm Reply Like. 05-01-2012, 11:59 AM #4 chassed. Melting Slicks . Member Since: May 2009. Location: Rio Rancho New Mexico. Posts: 3,123 Likes: 343 Received 281 Likes on ...Upgrade your LS1 or LS6 engine with our Remanufactured CNC Ported 243/799 Cylinder Heads with .650 Springs and 2.02/1.59 Valves. These high-performance heads, designed by Chevrolet, are meticulously remanufactured to exceed OEM specifications, ensuring top-notch quality. These CNC Ported LS heads, part number ALL-65056PC, fit engines within the ...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.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.Talking about cleaning heads and valves. Discussed when a valve job is needed compared to recommended. Chamfering the edges of the combustion chambers after ...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.Suicidal Racing. 26755 posts · Joined 2006. #6 · Jul 31, 2012. Maybe its me an how i keep reading it..but it seems you think 317s flow more then 243s or 799s...they have the same ports as a 317..,317 just has a larger chamber 72 or 74cc vs the 243/799 64cc... some 5.3s have 799 heads stock.not sure on yrs though.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 ...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.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.Jun 2011. Location. Clarksville, TN. Posts. 198. 862 heads for a 4.8L ? Got lucky at a local junkyard and snagged a set of 862 heads off a wrecked z71 2000-2006 body style. thinking about building these (port n polish, roller rockers, valves n springs to go with a nice cam) to put on my 06 gmc 4.8L .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 ...Newly reworked 243 heads versus AFR heads. Hi guys, I have a 2006 C6 A6 with 145,000 miles on it. Mods include K&N breather, LG Long Tube Headers, and a Circle D stall converter. I recently swapped my LG G5XB cam for a new LG G5X3 114 cam. I have factory 243 heads that have just had a competition valve job including new guides, valves, Comp 921 ...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 ...Talkee lists some free party-line phone numbers are 712-432-7463, 218-862-3788 and 218-862-3784. Numbers for specific groups such as Afro, Anglo, Asian or gay groups are found on t...The ideal RPM range for a camshaft on a 5.3 with 862 heads depends on various factors such as the intended use of the vehicle, the type of camshaft, the engine components, and the desired performance. Typically, a camshaft with a duration between 212-218 degrees and a lift around .550"-.600" can work well with the 5.3 engine and 862 heads.The combustion chamber diameters can play a big role in hindering flow and performance. The 706/862 combustion chamber diameter measures out at around 3.670" and the 243/799 combustion chamber messages out at around 3.880” and giving the fact that the LM7 5.3L engine bore is 3.780" this more than likely has something to do with the power loss ...Product Details. Lingenfelter offers a CNC ported version of the 243 casting aluminum cylinder head used on the 2001 - 2004 Corvette ZO6, Cadillac CTS-V and the 2005-2007 LS2 powered C6 Corvette, 2005-2006 GTO & SSR. The port and chambers are carefully designed to provide the best combination of high flow capabilities and improved port …The 243 heads produce about 5% more power on flow alone. If you were to judge the 243 heads vs. the 241s on head flow alone, you’d get a slight power edge. This benefit occurs because of the hollow valve stem, delivering a better RPM potential that stands up to more supercharger or turbo applications.The GenX 205 heads were combined with a healthy Comp cam (Grind # 277LrR HR13) that featured a .614/.624-inch lift split, a 227/243-degree duration split, and 113-degree LSA. The spring package ...You are much better off with the 706/862 heads from a compression standpoint. 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 5.3. The 706/862 respond very well to a light runner cleanup and a good multi angle valve cut.53 posts · Joined 2010. #4 · Nov 12, 2017. Unless you're spending money on AI ported 243's, go with the LS3's. LS3's flow more and will keep the port velocity up compared to the typical hogged to hell port jobs I've seen on factory cast heads. There are very few shops that port heads well, with AI being the best around.Find Chevrolet Performance LS3 Cylinder Heads and get Free Shipping on Orders Over $109 at Summit Racing! Fit any LS engine with Chevrolet Performance LS3 cylinder heads. Manufactured from aluminum alloy, these GM stock replacement heads are assembled with intake and exhaust valves, stem seals, retainers, springs, and locks. Great cylinder head airflow has always supplied the LS Series with ...The LQ9 is a 6.0L Gen. 3 small block engine used in GM trucks between 2002 and 2007. For marketing purposes, it was also known as the Vortec HO 6000 or VortecMAX. The information listed here is for the stock engine. Mechanically similar, General Motors' LS and LS-based Vortec engines wound up on almost every branch of the GM family tree ...The main difference between 799 and 243 heads is the amount of valve lift that they can provide. 799 heads have a higher valve lift capability than 243 heads, meaning they can provide more airflow into the engine. This often results in increased power output from the engine. 243 heads also tend to be lighter than 799 heads, which can be ...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.227cc SBC Race Cylinder Head. AFR's 227cc "Race Ready" and "Competition" heads feature 100% CNC ported intake, exhaust & chambers, A356 aluminum castings and high quality components throughout. This head features 60/40 valve spacing and requires shaft mount rocker arms for optimum valve train geometry (can be used with .050 offset intake ...13K views 96 replies 22 participants last post by treys06GTO May 31, 2013. 420GTO Discussion starter. 1052 posts · Joined 2006. #1 · May 22, 2013 (Edited) There are a set of 243 heads available ported by AI, 232CC package including Comp dual springs, but for a lil more ($400) there are a set of AFR 205's OR Cartek 4x heads available.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...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 ...Newly reworked 243 heads versus AFR heads. Hi guys, I have a 2006 C6 A6 with 145,000 miles on it. Mods include K&N breather, LG Long Tube Headers, and a Circle D stall converter. I recently swapped my LG G5XB cam for a new LG G5X3 114 cam. I have factory 243 heads that have just had a competition valve job including new guides, valves, Comp 921 ...7477 posts · Joined 2005. #29 · Nov 2, 2013. Stock 243 heads are good for about 20 hp on a 2004 LS1 and can often be found for about $400 or so. 2004 torrid red with red interior A4 GTO (1 of 499) TR-230/236 cam/TEA ported Trick Flow 215 heads/4" CAI/100mm MAF/ported FAST 90/Kooks/Magnaflow.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.stock 862 heads vs stock 243. Jump to Latest Follow 54K views 39 replies 8 participants last post by 71 chevy Dec 11, 2013. 7. 71 chevy Discussion starter 1938 posts · Joined 2009 Add to quote; Only show this user #1 · Dec 4, 2013. i want to know if I would pick up anything swapping in STOCK 243s heads in place of stock 862 truck heads that i ...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.We Step Up The Power With A 468ci Engine To Log The Performance Of Nine LS3 Rectangle-Port Heads. ... 243. 0.700 . 359 . 246. Like the offerings from Mast Motorsports, the Dr. J's CNC LS3 heads ...Our fully CNC'd 243 heads give your choice in stock 2.0intake/1.550 or upgraded 2.02Intake/1.600 exhaust with an intake flow of 320cfm and an exhaust flow of 221cfm. 832-619-1622; 7413 Wright Rd. Houston, TX 77041; [email protected]; Skip to content. Home. CNC Porting. Service Prices. Cart. Checkout. Tech.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 ...The 243 heads have larger intake and exhaust ports than the stock heads, allowing for an improved airflow that increases torque and horsepower. With this increased airflow comes a greater capacity to burn fuel efficiently, giving you better performance overall. Additionally, these upgraded 243 heads are designed with a higher-lift camshaft so ...Our fully CNC'd 243 heads give your choice in stock 2.0intake/1.550 or upgraded 2.02Intake/1.600 exhaust with an intake flow of 320cfm and an exhaust flow of 221cfm. 832-619-1622; 7413 Wright Rd. Houston, TX 77041; [email protected]; Skip to content. Home. CNC Porting. Service Prices. Cart. Checkout. Tech.Dec 28, 2011 · 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 Stock Head Flow NumbersThe reason is simple: The more you squeeze the air and fuel mixture in the combustion chamber, the more power you can create. In theory, forcing air and fuel in as small a combustion chamber as possible (measured in volume) will yield maximum engine compression and horsepower. There are a number of ways to accomplish the task.Where the stock 243 heads featured 65cc chambers, the 317 heads featured 72 cc chambers. The 317s were given the nod over the 243 since they offered the larger chambers that most closely duplicated those on the LS3 (71cc). The biggest difference between the 317 cathedral-port heads and the LS3 heads was the port shape and …The all new PRC aftermarket casting LS3 heads are the perfect option for customers looking for the ultimate in LS3/L99/L92 cylinder head technology. The 13-degree valve angle will allow for the ability to run more compression and larger camshafts thanks to additional piston-to-valve clearance!! Lift. Intake Flow.You are going to make more power with 243's than 853's no matter what. Now it comes to cost vs. results. For the $600 or so for a stock 243 head, I probably wouldnt do it. In our experience, the best "budget" 243 heads are the Patriot Stage II LS6 heads. Those heads, with a LG G5x3 has been one of our most proven budget orientated power combo's.Expedited Core Exchange - We will ship you a set of CNC ported heads fresh out of the machine and set up to your cam specs once the order is placed. Once your usable cores have made their way to us, LME will refund the cost of the cores. Current GM LS1 243 Cylinder Head core value is $250.00. **No matter what method you choose, once order is ...CNC ported GM 243/799 Castings Competition 5 Angle Valve Job 2.0" Intake & 1.55" Exhaust Valves 227cc intake runner, 84cc exhaust 62cc chambers Completely Assembled with our QCS Dual 660 Valve Springs w/ Titanium Retainers Laser Engraved QCS logo Sold in Pairs Lift Intake Flow Exhaust Flow .200" 148Our 706 & 862 ported heads include: Our in house CNC port. PCD surfaced to your desired chamber size. Proprietary competition valve job. Hand blended valve job. ***This is our most common setup, but if this doesn't meet your needs please call us so we can get you set up to your needs***. Intake valve: 2.02 Exhaust: 1.57.. You could bore to the LS1 pistons run them and get a 862 heads with a valve job and BTR springs/retainers and a trunion upg Of course, today's 5.3 and 4.8 both have 243 heads that are factory-designed. 243 heads were included in the LS6 engine produced between 2001 and 2006. You can determine the 243 heads on the 5.3 by examining the three-digit stamping next to the valve cover. The Sierra 1500 and Silverado from GM produced between 1999 and 2013 had 243 heads.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 ... Jun 22, 2021 · Working with the intake Aluminum vs aluminum construction - Both 862 and 243 heads are cast aluminum. This means they have the same weight and heat dissipation properties. So in summary, 862 LS heads offer performance advantages of higher durability, better torque, and easier installation. The stock 243 heads are not a big restriction for making power on otherwise ...OP: difference is one is sand cast (853) and rougher feel where not machined and the 241 is smooth cast. Early 853 heads can not be used w MLS gaskets and later ones can. the difference is the deck surface where the head gasket goes around the perimeter there is a large notch that will not compress the gasket surface. We may earn a commission for products purchased through links...
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