Like the 317s, the 241 heads out-flowed the 706 heads, but once again, that airflow did not translate into power production. Although the cylinder heads were made originally for the 3.90-inch bore, they fit perfectly on 5.3L and 4.8L blocks (3.78-inch bore). By Albert, What Does It Mean When It Says Check Awd System. The upgrades included a 58x crank trigger wheel with the cam sensor moved to the timing chain cover. If I keep my original crank and have the block bored .020 over with new pistons, do you think I could do enough modifications to the crank, intake, and heads to get this kind of power? It is clear that the LS6 was a pinnacle in Head Design by GM. In terms of peak flow, the 241 heads offered 242 cfm at 0.700-inch lift from the 199cc intake ports, and 204 cfm from the 71cc exhaust ports. CNC Ported LS1/LS6 243/799 Cylinder Heads .650 Springs 2.02/1.59 Valves PAIR, Chevy Cylinder Head LS1/LS6 243/799, Year:97-04, 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. Easy Guide, Symptoms of a Dead Cylinder (Causes and Repair Cost), 2023 Car, Truck and Vehicle How To Guides - Vehicle Freak, Do Motorcycle Exhaust Need Baffles? The best way to be sure is to use this spotters guide and look carefully at the block and heads. In fact, they can make more power than a LS6 or LS2 with boost due to the thick cylinder walls. The #799 cylinder heads are reportedly the same casting as the LS6 and LS2 #243 heads, minus hollow exhaust valves and high-performance valve springs. 5.3L Chevy LS Engine Spotters Guide and Budget Build - MotorTrend For instance, the 799 cylinder heads come with a smaller combustion chamber than its counterparts. These mods can be done in your garage, but the tune wont be optimized. If you are contemplating a porting job, choosing the 799 cylinder heads will be wise. It is no wonder that the 862 heads are so popular among General Motors' LM7 engine owners, for these cylinder heads pack plenty of power and a great design. The LS engines designed with 799 heads were 5.3L and 4.8L truck engines. However, Chevy unveiled the L20 4.8-liter engine, which had the 799 cylinder head in 2010. Inside are ARP mains and head studs, and an M365 Melling oil pump. (Is It Bad to Remove Them? Guide to LS iron-block truck/SUV motors - WhichCar The extra cubes bring boost on quicker which means you can use bigger and more-efficient turbos. 2007 Chevy trailblazer SS. NOTE: You can find engine specs and detailed engine upgrade advice for every LS and LS-based Vortec truck engine in one place: The Definitive Guide to LS Engine Specs and LS Engine Upgrades. Engine Size: 5.7L - 350ci - V8. Why Chevy 706 Heads LS Make a Great Choice? - Allied Motor Parts Share with your Friends!Facebook @ SPPTV YouTubeInstagram @ SPPTVonYouTubeSnapchat @ SPPTVPO BOX:Rob ExnerPO BOX 99900 LX 087 592RPO GARDEN CITYWINNIPEG MB R2V 5A2CANADA The combustion chambers on the 706 heads measured 61.5 cc, while the intake and exhaust port volumes checked in at 197 cc and 69 cc, respectively. Heres a table with common performancerotating assembly combinations. This record is an incredible milestone in the motor racing industry, and it truly showcases Capizzi's talents as an expert driver and racer. 862 vs. 799 heads??? big difference or no? | S-10 Forum Ask your tuner what injectors they prefer and have them ready to save yourself an extra trip to the dyno. These volumes are larger than most other heads available, allowing more air to enter the combustion chamber and be expelled through the exhaust pipe, resulting in increased power output while reducing fuel consumption. Your email address will not be published. These heads are for a new project that will be beginning soon on the channel, more on that soon! The LQ4 also featured an upgraded valve train, camshafts and larger injectors which allowed for increased power output when combined with aftermarket parts such as cold air intake systems or exhaust upgrades. The LM7 cam is still a great choice for those who are looking to extract maximum low-speed grunt from their 5.3L engine as it will provide smoother throttle response and more usable power across its entire operating range than many other designs on the market today. These motors are capable of making a lot of horsepower, and respond well to upgrades like turbos, superchargers, high-flow cylinder heads, intake systems, cams, and nitrous oxide. Depending on how much power you intend to make, upgrading to largerfuel injectorsmay be needed. There are a few other parts needed for a L33 cam swap such as an LS2 timing chain, LS7 spec lifters, LS2 timing chain damper and thick-wall chromoly pushrods. The 706 heads offered considerably lower peak flow numbers though, checking in with a maximum of 237.1 cfm at 0.700 inch lift - still respectable but not quite as good as their counterparts. The 799 LS heads have 2.00-inch intake valve. Rebuild engine? What intake should I use? We also took the liberty of measuring the combustion chamber diameter (distance across) to illustrate how the factory sized them for their particular target bore size. The exhaust valve should ideally be 85 percent of the size of the intake valve. The amazing success of this design is evident in the fact that its casting number, 243, was recycled for use on the LS2. Below are some more upgrades you can make to improve the performance of an L33. The sophisticated architecture, cathedral-shaped port, and smaller combustion chamber work amazingly on these truck engines. It was known as the Vortec 5300 HO and made more power than the older LM4. Despite having been out of production since 2006, this engine remains popular amongst performance enthusiasts due to its strong performance capabilities even without modifications. The LC9 engine is a 5.3L, Gen. 4, aluminum small block engine used in GM trucks and SUVs between 2007-2011. So lets look at the 799 heads and what makes them a nice choice for a porting job. This cylinder head also has a compression ratio of 9.5:1, which allows for improved fuel economy levels without sacrificing too much power output from your engine. Turbo cams reduce overlap with less exhaust duration split in relation to the intake. This specific guide is for the GM LC9 5.3L engine. An LS3 or LS9 cam makes good power, but not where you want it if youre using the L33 engine in a truck. Luckily, these stock heads can be CNC-ported in order to increase the airflow and make them more powerful. For many people, selecting suitable cylinder heads can be pretty tricky. Furthermore, even if you do decide to switch out the heads, there would still be no difference in horsepower output. The 706 heads were simply better than the 799 heads through most of the curve. In 1999-2000, LQ4s came with #373 or #873 heads that had 71cc . The 243/799 heads came on the 5.3 "L33 HO" motor in 05. The 799 LS heads have a D-shaped port. The aftermarket is strong,crate enginesare available, and used motors are often cheaply sourced through junkyards. Trans computers were external early on and switched internal later. The only giga-trick parts are in the valvetrain. Your email address will not be published. It produces an impressive 320 horsepower and 340 lb-ft of torque from its factory settings. The specifications are almost identical; therefore, the cylinder heads are fully interchangeable, and they offer the same power output. Finding 799 heads for sale can be a challenge, but you can get your hands on the perfect cylinder heads for your needs with the right resources and patience. The valves on each type of cylinder head can vary. The question now is where that limit occurs. The LC9 engines also came with 799/243 heads. However, unlike the 243 heads, they do not require cleaning. The configuration allows for a higher compression ratio, resulting in more horsepower. This will definitely free up a few horsepower and gives the little engine a big personality. They have far outflowing capabilities compared to their cathedral-style counterparts, making them one of the top LS cylinder head options available today. The 799 cylinder heads are in the similitude of the 2004 LS2 cylinder heads due to the triangle casting marks similarity. The Coefficient of Discharge is a calculation of the airflow versus valve sizing, and gives a much more accurate picture of the power potential of these heads. So I guess its LC9 5.3 . open. The port volumes were within a couple of cc's of the 241 LS1 heads, and the peak flow differed by around 5 cfm despite the 706 heads having a smaller intake valve size. Wondering if a L92 is even feasible. For fun, he runs his 427-powered C5 Z06 in ECTA land-speed racing, at OPTIMA street car events, and at a mix of autocross, drag racing, and track days. The exhaust port features a D-port shape that reduces back pressure while still providing plenty of exhaust flow for increased horsepower and torque output. It was actually the 8th digit of the vehicle identification number. Which one do you think would be better and what unexpected changes are needed for both. The 799/243 will kill what little compression you have now unless you mill them. It is the Lt model and the 8th character of the VIN is 7. The L33 intake wasnt particularly good and had a 3-bolt 78mm DBW throttle body. Cylinder heads are an important part of any engine and can make a big difference in the performance of your vehicle. The shape is designed to increase airflow and power. It is vital to note that combustion chamber size plays a significant role in either increasing or reducing the compression ratio. Are the 799 heads on LS1 interchangeable? It is well known that the 799 heads have a positive effect on engine performance, as they feature smaller combustion chambers than standard engines. Since the cylinder heads come with a smaller combustion chamber, you will have to mill the cylinder heads to a minimum of 0.025 to cover up for the former bigger combustion chamber size. The exhaust valve is responsible for expelling the burnt gases off the combustion chamber of an engine after the power stroke. Only issue is I want to keep my cable throttle body and Im not ide how I can run a gen ov block with a Gen 3 ecu. Next to the 706 heads, the 799s featured the smallest combustion chamber at 64 cc. The 799 head cc is pretty smaller compared to some others. The L33 swap is a pretty common one as LS1s are getting hard to find. The valves are responsible for letting air and fuel into the cylinder and the exhaust from that combustion out of the cylinders. 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 made. The 243 was created in a GM research laboratory, while the 799 was later adopted by other manufacturers later on. A set offorged pistonsshould be high on your priority list. Apr 26, 2023, 2:58 AM PDT. They offer excellent performance with increased horsepower making it a preferred choice for a porting job. link to Alternator Overcharging - Causes and Fixes, link to LS Head Bolt Torque Specs and Sequence. They can be found for around $1,300 which is inexpensive for an aluminum block engine. are some of the most popular heads used in LS engines. While this could be seen as a positive trait of the 799 head, its chamber volume was only 2.5 cc's different from that . NOTE: You can find engine specs and detailed engine upgrade advice for every LS and LS-based Vortec truck engine in one place: The Definitive Guide to LS Engine Specs and LS Engine Upgrades. Required fields are marked *. The material of the cylinder heads is another essential feature. The best way to identify a 5.3L is the dish in the piston; the 4.8 has a flattop. is the best place to get them. In production these heads have been repurposed on the aluminum 5.3L truck engine (L33, "799" casting), which proves that despite being originally made for a 3.90-inch bore, these heads even fit on 4.8/5.3L blocks (3.78-inch bore), and are quite abundant used. Mechanically similar,General Motors LS and LS-based Vortec engineswound up on almost every branch of the GM family tree: Chevy, Pontiac, GMC, Cadillac, Buickheck, even Saab, Hummer, and Isuzu got some LS love. I am also looking fo a tbss or 07 NNSB intake. An electric fan kit will free up that power. Cam Motion ground the cam with 223/229 duration at 0.50; 596/596 lift on an LSA is 117. . First, you want to avoid the Gen III heads with the "battery" castingthey are crack prone. The 209cc intake ports flowed as expected, but the 74cc exhaust ports were not quite up to snuff. Something to keep in mind is the 2004 and later engines (even Gen. 3) had two head bolt lengths vs. three on the earlier engines. But . [] Download Image More @ http://www.onallcylinders.com []. Beyond that, .575 to .600 in. This charge is FULLY REFUNDED upon return. This also helps reduce emissions by allowing more complete fuel combustion in each cylinder. This process can be time-consuming and costly if not done correctly, so its important that you understand all of the potential pitfalls before attempting this swap. The factory cam is tiny and really holds the engine back. All together, it is easy to see why these 862 heads are such a sought after choice when looking to upgrade or replace older components on your LM7 engine. The intake port volume for 799 LS heads is 209 cc. Engine specialists have taken these powerful components and remanufactured them at more budget-friendly prices. The factory main caps arent doweled. The 862/706 heads have smaller combustion chambers than the Gen IV, raising the compression ratio when swapped directly. The main difference between the 243 and 799 heads is that one was designed for GM engines, while the other can be used on various engines from different makes. Overinflated Tire by 5 Psi: What Will Happen? The 5.3 "LM4" is what I have in my Rainier and it had a short production run and was used in the 03-04 GMT360 vehicles and the SSR. In an internal combustion engine, the compression ratio is the ratio between the volume of the cylinder and combustion chamber, In other words, compression ratio can be defined as the ratio of the volume of the cylinder and its head space. You'll also want to consider how often you drive and what kind of conditions you'll be driving.