What you need is a cam that delivers a gut-punch right when the converter hits. 5.3L Chevy LS Engine Spotters Guide and Budget Build - MotorTrend The shape is designed to increase airflow and power. The cherry on top is its not saddled with Variable Valve Timing (VVT) or Active Fuel Management (AFM) found on some Gen. 4 engines. 243 came with sodiom filled stem 1.55 exhaust valves (lighter and more heat dissepation) and 799 came with regular solid stem 1.55. They offer excellent performance with increased horsepower making it a preferred choice for a porting job. Both the 243 and the 799 cylinder heads are General Motors' 3rd generation cylinder heads designed for V8 trucks, performance engines, and SUVs. Aftermarket heads reduce downtime and are cost-effective when you sell your old heads in good condition. Of course, the 799 heads are designed with a cathedral shape intake port. What heads came on LS3? A lot has been unveiled about 799 heads. Car Wobbles at a Very Low Speed (Causes and Fixes). 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. Simply put, the Gen III is easy to swap and cheap, and the Gen IV has better heads and more complexity. As stated above they are the same as 243 heads with a different casting method. Trans computers were external early on and switched internal later. Of course, the 799 heads are good. The 241 heads, compared to the 706 heads, offered larger 68cc combustion chambers, which meant a drop in compression of roughly 0.70 points. However, unlike the 243 heads, they do not require cleaning. These 799 heads are the latest model and are made using the semi-permanent mold method. The specifications are almost identical; therefore, the cylinder heads are fully interchangeable, and they offer the same power output. For example, Corvette Z06 models feature 243 heads with sodium exhaust valves, which is typical for an L6 engine. The test engine was an easy choice, as the 5.3L was the go-to engine, especially for the power-adder crowd. The 799 is basically the successor to the 243 without any significant changes. 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. what LS heads to use on my 5.3 | Chevy Nova Forum When it comes to L98 cylinder heads, they are very similar to the LS3 heads. The size of the combustion chamber is the major challenge with swapping to 799 heads. The aluminum blocks have Siamese bores with sleeves that are bonded to the block, and other enhancements, making them durable for boosted power. It is important to understand the differences between 243 and 799 cylinder heads, as they are two of the most popular cylinder head options for a Chevy. It was known as the Vortec 5300 HO and made more power than the older LM4. Scroungers are known to CNC port the 862/706 heads to get them to outflow the more expensive Gen IV 243/799 head. The 799 heads have been amazing on the 4.8 and 5.3-liter truck engines since inception. in this thread in this sub-forum in the entire site. 4X4 . Cylinder head casting number for 5.3? | GMTNation Why Is My Car Accelerating on Its Own? The 4.8L has a 3.27-inch . If you are contemplating a porting job, choosing the 799 cylinder heads will be wise. CHP. 2007 5.3 with 862 heads? - ls1truck.com This is revealed in the 799 head specs outlined above. Check outPart 1andPart 2of our LS Spotters Guide.]. Hi, im going to put a L33 in my 1973 C10 shortbed. This was due to higher flowing Cathedral port heads, more compression, and a slightly bigger cam. 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 799 LS heads have a 1.55-inch exhaust valve size. The L33 crank was cast but strong. Drop-in .500-in. If you need any help finding the right set of heads for your engine, contact us, and we'll be happy to assist you. However, before porting, you should make yourself aware of the specifications. However, ensure to consider the pros and cons of swapping your current cylinder heads to 799 heads before a porting job. Inside are ARP mains and head studs, and an M365 Melling oil pump. i have every length exc for valves but i would just call the dealer and they can give u the lenght and pt#s if u need anytging else for stock 5.3 info i have it. A larger port volume results in more power, decreasing fuel economy. Vin.Seventh digit is 7. I have a 2013 Chevy Silverado 1500. Overinflated Tire by 5 Psi: What Will Happen? Another bonus of the L33 is it had beefier connecting rods than earlier Gen. 3 engines and had full floating pins. This will definitely free up a few horsepower and gives the little engine a big personality. The factory fuel pump will become a limitation around 430 whp, so you should plan on upgrading thefuel pumpas well. It connects the intake manifold with the cylinder heads. The early part of his automotive career included working for engine builders Scott Shafiroff and C.J. A better option is the Chevy Trailblazer SS or the 2007.5+ NNBS truck intake. The factory cam is tiny and really holds the engine back. They can be found for around $1,300 which is inexpensive for an aluminum block engine. When running boost, you can use a water-methanol system to supply extra fuel and lower charge air temps. 799 Heads: All About 799 LS Heads & Their Application. So I guess its LC9 5.3 . This is because the cylinder heads come with 64cc combustion chambers. If he is not in the garage fixing challenging mechanical problems, he is writing automotive repair guides, buyers guides, and car and tools comparisons. The main reason for going with a stroker forged crank is for the added cubic inches. The DOD, later called active fuel management (AFM) bungs, will be obvious on the Gen IV engines. While a smaller combustion chamber increases the compression ratio, the bigger one reduces the compression ratio. (Blurring Pictures Online), How to Gap Spark Plugs With and Without a Tool, Why Engine Is Hot and AC Turned Off (Causes and Fixes). On the other hand, some cylinder heads are designed with the best architecture that delivers top-notch power output with increased horsepower. Hey Allen, Cool ride! If you plan on running a power adder or have a long list of upgrades planned, its recommended that you take your truck to a chassis dyno tuner who can give you a custom tune. If you're uncertain, here are a few factors to consider before going for 799 heads. Wanting to go with 5.3 since its a bit cheaper and dont care that Ill be loosing performance. Of course, the question now is how would the four heads act under boost where the additional flow required might tax the maximum flow potential of the small-valve 5.3L heads? This time on SPPTV we head to our favorite junkyard to snatch some 799 LS cylinder heads we received a tip about. CNC Ported 862 LS Heads- The Ultimate New Gen Cylinder Heads The CNC Ported 862 LS Heads are the most demanding cylinder heads in the modern era. By Albert, What Does It Mean When It Says Check Awd System. The799 and 243 casting Cathedral-port cylinder heads can be CNC ported to flow close to the aftermarket heads. Reynoldo, youll love it after doing a LS swap. At Allied Motor Parts, we provide 799 LS heads for sale to customers who only want the best for their engines and do not compromise on quality or performance. Cam Motion ground the cam with 223/229 duration at 0.50; 596/596 lift on an LSA is 117. So, in the debate of 799 versus 243 heads, it can be determined that they are completely identical and interchangeable with one another. Until we find that out, all hail the mighty 706 heads. However, you may also find some heads made from cast iron. However, Chevy unveiled the L20 4.8-liter engine, which had the 799 cylinder head in 2010. Stay away from the LS4 from front-wheel-drive cars. Guide to LS iron-block truck/SUV motors - WhichCar Youre making more power than that.. Wind her out to 7k rpm with that intake for an accurate hp/tq figure. All rights reserved. Why Chevy 706 Heads LS Make a Great Choice? The Mini-Delphi/Multec II connector 25-pound injectors are a limitation at around 380 whp. However, it was outshone by higher duration cams like the LS1 which provided greater gains in horsepower and torque beyond 4,400rpm - making them better suited for high revving applications. The exhaust port volume specifies the total amount of exhaust gas that can flow out of the cylinders during the exhaust stroke. The 243-cylinder head has eight valves per cylinder (2 per valve) which help increase airflow into and out of the combustion chamber for improved engine performance. Not knowing it is a vin(b) 5.3 l33ho. The 799 heads offered the most flow, bettering the 706 heads by as much as 20 cfm at some lift points. These cylinder heads were originally designed for various models of Chevy vehicles and are compatible with LM7, LR4, and LM4 5.3 engines. Why Chevy 706 Heads LS Make a Great Choice? - Allied Motor Parts Cylinder heads are an important part of any engine and can make a big difference in the performance of your vehicle. I PUT A STAGE 1 TSP TRUCK CAM WITH AIR RAID INTAKE AND DYNOED 283WHP AND 302WTQ. This specific guide is for the GM LC9 5.3L engine. 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. The Gen III has the 24x reluctor on the crankshaft and can be run with a cable-driven throttle body and factory computer. The 241 heads were used on 5.7L LS1 applications and are considered by many to be just a minor step up in performance from the 706. It is clear that the LS6 was a pinnacle in Head Design by GM. The 243 and the 799 cylinder heads are practically the same. (Summit RacingsPaul Spurlock and Brian Nutter contributed to this article.). Hi Rick. The LC9 was the last of the LS base truck 5.3s any 5.3 for a truck after the LC9 is a newer version Of the old LS called LT with direct injection. Your email address will not be published. Bore 3 = 2.307 in. The size of the chamber can affect power and efficiency. The extra cubes bring boost on quicker which means you can use bigger and more-efficient turbos. Im building for factory reliability but adding a little boost for some extra power. Which one do you think would be better and what unexpected changes are needed for both. Check out the graphs for a full rundown, but the big surprise was that the amazing power of the legendary 799 (243) heads never materialized. Economical upgrades for 243/799 heads | LS1GTO Forums Welcome to rxmechanic.com. Meanwhile, a reduced compression ratio results in a cooler burning temperature. On the Gen IV, knock sensors are on the side of the block instead of in the lifter valley, and the cam sensor is moved to the front of the timing chain cover. Yes I had a 2013 Sierra sle as well with the lc9 13 is the last year till the swapped over body styles. Sometimes referred to as the LS6 , the LQ4 is a 6.0 litre member of General Motors' Vortec engine family.It was first introduced in 1999 and was used for both light and commercial duty applications until it was discontinued in 2006, making way for the new generation of engines from GM's LS range. The Dorman 615-901 has proven itself to be very close in power to the TBSS intake manifold. While they are similar to 2004 LS2 heads in terms of triangular casting, they do not require cleaning like the 243 heads. However, when it comes to performance, both are interchangeable and will provide the same power output. I dunno, milling to 59cc combustion chambers would be nearly 11.2 CR. are some of the most popular heads used in LS engines. Surprising HP Numbers From Our Stock LS Cylinder Head Test - MotorTrend It is an aluminum block 5.3 with either 706 or 862 heads, NON DOD. For a primer on the entire LS engine universe, readLS Engines 101: An Introductory Overview of the Gen III/IV LS Engine Family.]. Gen III/Gen IV LS Engine: Specs, dimensions, and Engine History - Holley looking for reliability with a little get up. Youll be knocking on 400 whp which is where the stock injectors max out anywayso its a fairly inexpensive proposition for the power youll be making! The Gen III block can be iron or aluminum, and you will see 4.8/5.3L cast into the front of the block. So all the way up to the end of 2013. i just called the dealership and they was able to ans all my quest. To maximize torque in the mid-range in a truck cam, manufactures close the intake valve at about 35-40 degrees (@.050 in.) After reading these recommendations, I cant stop grinning. If youre contemplating 799 heads vs. 706, they offer more advantages compared to 706 heads, irrespective of the common challenge with 799 heads. Some of the most cost-effective and powerful heads available for 5.3L, 4.8L, and even larger 6.0L LS engines are GM's 706 Vortec heads. Therefore, the size of the exhaust valve is an essential factor in determining how much power an engine can generate. Tuning the computer changes the fuel and ignition curves to increase performance. The 799 and 243 casting Cathedral-port cylinder heads can be CNC ported to flow close to the aftermarket heads. Keep in mind, if youre running a cam in the 230 range, piston to valve clearance needs to be checked and fly-cutting may be required. But on the upside, both respond equally well to porting. With these results it's clear that if you're after maximum performance then investing in some 799 head will give you more bang for your buck! Hello, Im wanting to delete the DOD in my 2011 Sierra 44 with a .525 or so cam, I am wanting to know the best parts I should use for lifters, push rods, maybe 1.8 rockers, springs, bushings, locks & or injectors. This is due to the larger exhaust port volume, which allows more fuel and air to enter the combustion chamber than necessary. 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. (Solved). The 243-cylinder head was mostly used on the LS6 and the LS2 engines. Lets talk about bottom-end upgrades. With a bigger cam you can mill the heads for up to 10.8 compression which runs on pump gas. You can achieve it with good drivability and power across the entire rpm range by upgrading the cylinder heads. Generally,supercharger cams and nitrous cams will have slightly more lobe separation and longer exhaust duration. The LS engines designed with 799 heads were 5.3L and 4.8L truck engines. 799/243 Heads - Cylinder Head - Remanufactured CNC Ported LS1/LS6 When testing the 5.3L heads, the 706 and 799 heads were compared to determine which offered the most flow. If you upgrade and depending on the injectors you run, you may need a fuel injector adapter harness. The 862/706 heads have smaller combustion chambers than the Gen IV, raising the compression ratio when swapped directly. Not only do they provide improved performance but also allow you to save money in the process - making them an ideal option if youre looking to get more out of your Chevy engine without breaking the bank. While they are similar to 2004 LS2 heads in terms of triangular casting, they do not require cleaning like the 243 heads. That will require fairly high octane. Valve Size: Intake - 1.89, Exhaust - 1.55, Port Volume: Intake - 197 cc, Exhaust - 69 cc, Chamber Diameter (distance across): 3.756, Valve Size: Intake - 2.00, Exhaust - 1.55, Port Volume: Intake - 199 cc, Exhaust - 71 cc, Chamber Diameter (distance across): 3.821, Port Volume: Intake - 212 cc, Exhaust - 76 cc, Chamber Diameter (distance across): 3.923, Port Volume: Intake - 209 cc, Exhaust - 74 cc, Chamber Diameter (distance across): 3.876. This put it within 2.5 cc's of the 706, meaning there was only a minor change in static compression between the two. The L33 swap is a pretty common one as LS1s are getting hard to find. The Definitive Guide to LS Engine Specs and LS Engine Upgrades, LC9 5.3L Engine Upgrade Guide: Expert Advice for LC9 Mods to Maximize Performance - OnAllCylinders. The 799 heads have a smaller combustion chamber of 64cc, which significantly increases the compression ratio. They are built with sophisticated architecture, including a cathedral-shaped port with smaller combustion chambers. My son and I are looking for the L33 now for a swap into his 1992 F150 extra cab short bed.