The 706Vortec heads are even slightly superior to the commonly found 862 heads. The reason is that the 706 heads are SPM (semi-permanent mold) made, while the 862 heads are sand cast. The SPM method is considered to be a more consistent process, but once you port the 862 head, any difference to the 706 head goes away.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 ...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 I have been playing around with some 243 heads, ported them to 225 cc on the intake port left the intake with a carbide finish and ported the exhaust to 83 cc stock the heads are 215cc/75cc. I just did a standard clean up bowl porting remove the rocker boss trim down around the guide valves are 2.02/1.57 cheapo stainless valves I was hoping ...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.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.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.Jan 21, 2022 · 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 ...I knew the flow was the same just didn't realize gm put the 243's on the 5.3's. I better look at the driver side because I remember GTO's and vettes with 1 - 799 head and 1 - 243 head on the other side. My LS6 has 10.5:1 with 243's and I love it. The 09' has great response also eventhough I haven't tuned it yet. 97 GMC, 2002 LS6.When the LS 243 Cathedral Port cylinder heads are installed on an LS6 engine, the results are remarkable. The improved airflow, combustion efficiency, and larger valve sizes provided by the LS 243 heads contribute to increased horsepower, torque, and overall performance gains. Experience improved throttle response, heightened power delivery ...The 799 head is designed and made to be compatible with high-performing LS engines, such as 4.8L, 5.3L, 5.7L, or 6.0L, etc. These vehicles require maximum airflow, making the 799 head an ideal choice. On the other hand, the 862 head is compatible with LR4, LM4, and LM7 and such engines where low torque is more essential than better horsepower.Milled 243 Heads Shorty Headers 18" MagnaFlow CAI Tube w/stock Air Box Bone555+6VEFCpe+2ZERO(02)6kRPMabuse.hpt Bone555+6VEFCpe+2ZERO(02)6kRPMabuse.hpt. 01-27-2018 #2. cobaltssoverbooster. View Profile View Forum Posts Senior Tuner Join Date Dec 2008 Location Nevada Posts 4,452.3012 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.The 243 and 706 heads are the exact same. The only difference is that on the ls6 specific 243s, the exhaust valves were sodium filled to make them ever so slightly lighter. The 243 heads and 799 heads are the same. The 706 heads are the same as the 862 heads. Yep I'm dumb.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.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.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...I did a 408 cube ls using a cathedral port head. It was the 243 casting, but I don't think there is a big difference in potential. It made good power for a pump gas street engine. Had 10.7/1 comp, 243/258/110 comp cam with .625" ish lift. sv intake, 243 heads ported reasonably well with 2.02" 1.56" valves 50* seats, whitener 4150 carb.Chevy Cylinder Head LS1/LS6 243/799 - PAIR, Year:97-04. NEW CNC Ported LS1/LS6 Cylinder Heads .650 Springs 2.02/1.59 Valves PAIR. CNC Ported LS1/LS6 243/799 Cylinder Heads .650 Springs 2.02/1.59 Valves PAIR. Check out Our Other Articles: Everything You Need to Know about LS3 Heads. 823 Heads - Everything You Should Know About. All About 243 ...799 Vs 243 Heads: Main Feature Comparison. Though the 799 and 243 cylinder heads are similar in many ways, you can see from the table above that there are slight differences as well. But does it mean they perform differently? Well, the only way to find that is to compare the important features first. In the following part, I have compared some ...Over the weekend, robbers broke into the crypt of a Dublin church and stole the head of an 800-year-old mummy called “The Crusader.” Grave robbing might sound like a crime from a b...It uses a shorter case than the .243 Winchester—1.920-inch vs. 2.045 inches—allowing for a longer bullet length outside the case in the same length magazine, and maintains the 6.5 Creedmoor's 30-degree shoulder. Snow has found this extends brass life, as well as giving more room in the shortened case. The Hornady Precision Hunter load ...You could bore to the LS1 pistons run them and get a set of ported 243's. Add a Fast 90mm intake, cam, and you have an 400hp iron block LS6. Thats easily a 100K mile motor. For a stock 5.3L port the heads, cam, and a LS6/Fast intake and it might make 400hp on a engine dyno. But would make 300-325hp at the wheels.The '02+ LS6 heads have light weight valves. how much does a good porting cost. The LS4 front wheel drive engines also have 243 heads. The LS6 heads also used the lighter Valve that are 0.6mm or 0.023622" longer, hollow stem intake, and hollow stem sodium filled exhaust valves. but the 243 head casting is the same.Location. Nebraska. Feb 15, 2009. #6. I have a 6-284 and my idiot ex-hired man had a 243 AI and they both shoot well. My 6-284 is on the edge with high BC bullets and is very picky. I have suspected that that the 6-284 would be better suited to lighter bullets with a slow twist.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.Our 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.Remember that the '461X heads were used in 1961, 1962 and 1963 with valve sizes 1.94/1.50 only. The revised 461 heads were available starting in 1964 models with either 1.94/1.50 or 2.02/1.60 valves, depending on application. The later 461 or 462 heads would be my choice for a nostalgic look and high performance.According to the trusty flow bench, the chamber work did indeed improve the flow rate of our 706 heads, with the largest gains coming at 0.200 lift for the intake and 0.400 lift for the exhaust ...1518 posts · Joined 2009. #7 · May 3, 2010. I just got my quote from AI for their full 226cc CNC work and the price can not be beat. With shipping back from them the price is just a bit over $1,000. They also have a budget pricing port job as well but yields about 10rwhp lower.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.Casting number 862 or 706 heads were used and sported a 61cc chamber but had tiny 1.890 intake valves. The stock heads can be CNC-ported for more airflow and milled up to .030 inch for more compression. Flow numbers can be as high as 325 cfm at .600-inch lift. Lightweight, hollow-stem LS3 valves can be cut to 2.040 inches to fit the seats.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.I knew the flow was the same just didn't realize gm put the 243's on the 5.3's. I better look at the driver side because I remember GTO's and vettes with 1 - 799 head and 1 - 243 head on the other side. My LS6 has 10.5:1 with 243's and I love it. The 09' has great response also eventhough I haven't tuned it yet. 97 GMC, 2002 LS6.53 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.Both of the cylinder heads possess the same valve size. Additionally, they have ports and chamber cores of the same size. The actual difference lies within the compression ratio of the two. 862 heads are cast on sand molds, but 706 cylinder heads are cast on a semi-permanent mold. 862 heads also fit into smaller combustion chambers as compared ...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.lt1z. 30920 posts · Joined 2007. #6 · Mar 12, 2015 (Edited) A 317 head on an LS2 will be 10.0:1. A 243 on a LQ9 will be 10.9:1. Only major difference is combustion chamber cc. I would not go with less then 10.0:1 compression on a 2300. Mill a set of 317s to 70cc, run an LS9 gasket and head studs. C6 M6 Vortech 857/725.May 7, 2023 · Street Performance of The 706 Head. It’s worth noting that the 706 heads have a larger combustion chamber than the 862 heads, which measures at around 71cc. While this might sound like a disadvantage, it can actually be helpful for engines running on lower-octane fuel or those using forced induction.Travolta's 707 is now headed back to Australia, where it will be maintained and put on display with the Historical Aircraft Restoration Society. John Travolta by any measure is an ...The 799 and 243 casting Cathedral-port cylinder heads can be CNC ported to flow close to the aftermarket heads. With a bigger cam you can mill the heads for up to 10.8 compression which runs on pump gas. ... There is no reason to put the weaker 862 head on an L33 when the engine comes with the best flowing cathedral port heads GM …I recently jailbroke my iPhone and now that it's done I'm very overwhelmed by Cydia. I've downloaded a couple apps, but I don't understand most of what I'm looking at. The descript...The LS4 is a 4th gen, 5.3 l aluminum small block engine that was used in GM cars between 2005 and 2009. They had cathedral port cylinder heads and used Active Fuel Management (AFM). The LS4 cylinder heads came with two casting series numbers - 799 and 243. The combustion chamber volume is 65cc.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. Typical gains are 10-20rwhp. 226cc Full CNC Porting Package The go-to head for 450-500rwhp 5.7/6L's.The LS3 was run with a Holley HP management system and FAST injectors. With stock heads, the modified LS3 combination produced 552 hp at 6,400 rpm and 513 ft-lbs of torque at 5,000 rpm. After installation of the TFS Gen X 255 heads, the power numbers jumped to 571 hp at 6,500 rpm and 525 ft-lbs of torque at 5,200 rpm.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 ...Unless your building something something over 7000rpm an OEM head is the way to go. People routinely get 1000hp out of them. On 4.8, 5.3, 5.7, NA 6.0 - I always recommend the 243. Maybe even milled a touch if needed. On 6.0+ the 823 variant of the rectangular head is great. 65 Chevelle Malibu 2dr HT LS Swapped.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 ...Feb 18, 2024 · 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 ...See All 18 Photos. After installation of the TrackMax cam, the power output of the 6.0L LY6 jumped from 443 hp and 467 lb-ft of torque to 514 hp at 5,900 rpm and 493 lb-ft of torque at 4,600 rpm ...Bascially here are my options. 1. Keep 882 heads (already have crane springs), add an aluminum intake manifold ($140), 8" harmonic balancer ($60), new gasket set ($40). Total $200. 2. Buy a set of used Vortec Heads at the local junkyard ($210), Vortec intake manifold ($140), center bolt valve covers ($40), balancer & Gasket set ($100). Total $450.Dec 24, 2017 · In terms of cylinder heads, we included the 706 small-valve 5.3L heads, the 241 (LS1), 317 (6.0L truck), and 799 (as a stand-in for the hallowed 243) heads. The idea was to flow and measure each ...BTR HEAD GASKET - 4.8/5.3/LS1 - SOLD IN PAIRS - BTR98544. WILL NOT WORK WITH EARLY STYLE NOTCHED LS1 CYLINDER HEADS! BTR has sourced our very own MLS head gasket that can be used on 4.8, 5.3, and LS1 engines. This is a DIRECT REPLACEMENT for the LS1/LS6 GM head gaskets. This gasket has everything you know and love from the GM version: High ...Aug 18, 2011 · 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 having a blunt front end, you would expect it to be slower than the pointy 6.5 front tip. However, its body build allows for a larger volume of powder, which boosts its muzzle velocity significantly. Although both cartridges recorded high speeds, there is a slight difference that sees the Grendel lose.Easier to replace a head if more than a few. Yes, it's 2009. I've already discussed it with service guys and they said that it's ok, 823 and 5364 can be installed together even in Arlington on factory because it's absolutely the same. This is an older thread, you may not receive a response, and could be reviving an old thread.Running just 7 psi, the turbo system improved the power output by 243 hp. But the real question is, would the 706 heads still make more power under boost? After …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.. Dec 28, 2011 · Casting Number 706 and 862 Head: 1999+ 4.8L / 5.3 LitDescription. This program works on the following head casting numbe 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 headsReceived 26 Likes on 26 Posts. I took my 243 heads and had them cleaned up ( polished ) cleaned up ruff edges, but not ported. Had them milled to about a 62-61.5 cc chamber or something like that. run a 224/224 581/581 112+4 comp cam. comp 918 springs, comp rockers. Smith brother push rods. 232cc 243's vs 260cc 821/823's. Jump to Latest Follo 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.May 7, 2023 · Street Performance of The 706 Head. It’s worth noting that the 706 heads have a larger combustion chamber than the 862 heads, which measures at around 71cc. While this might sound like a disadvantage, it can actually be helpful for engines running on lower-octane fuel or those using forced induction. Why are Chevy 706 Heads better than 317 or 862 Heads? 706...
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