The 243 heads came on the LS6 engine produced from 2001 to 2006. It was typically found in the C5 Corvette, but it was eventually ported to the LQ4 and LQ9 to meet truck specs.
Did the 5.3 come with 243 heads?
Q: Did the 5.3 come with 243 heads? Of course, the 5.3, as well as the 4.8, come with factory-designed 243 heads nowadays. The LS6 engine designed between 2001 and 2006 came with 243 heads.
Does LS2 have 243 heads?
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.
How can I tell if I have a LS 243 head?
You can identify which head you have by looking at the three-digit stamping next to the valve cover; for example, the LS1 used head castings 339 and 806 through 1998, and 853 and 241 from 1999 through 2004. The 243 head came on the more powerful LS6 engine from 2001 to 2006, and was used in C5 Corvettes.
How much HP does 243 heads add?
A stock pair of 243 heads can gain about 20 hp on a bolt-on LS1. Since you already have a cam, you might see a bit more. If your budget does not allow a full porting job, don't sweat it, just swapping to 243 alone will be a big help.
17 related questions foundWhich LS heads are the best?
The LS6 was designed specifically by GM to surpass the LS1 as the best performance head, and it did such a good job that the “243” casting was recycled on the LS2. Aside from the LQ9, which is a copy of the LS6, these are the best performing of the OEM cathedral ports.
How much HP does ported heads add?
How much HP does a port and polish give you? Head porting is probably the single most critical piece of adding HP. you can gain 20-30 from a really good port job.
Are 243 heads Cathedral Port?
Essentially a 243 head with different casting numbers, the 799/243 heads are considered to be the top of the line, factory, cathedral-port offerings. Tested on a flow bench, the 799 head offered right at 249 cfm at . 700 lift on the intake and 191 cfm on the exhaust.
What LS heads are Cathedral Port?
Cathedral port heads came on the original (Gen III) LS1, but were also used on the performance-oriented LS2 and LS6 versions. Cathedral port heads were bolted on literally millions of truck variants, which included (among others) the 4.8L LR4, the 5.3L LM7, and 6.0L LQ4.
What heads on LS3?
The LS3 821 heads had hollow-stem valves, as did the LSA supercharged engine with the 863 heads. Heads for the LS9 used titanium intake valves like the LS7. The main difference between and LSA and LS9 head are the valves. The LSA heads also used a stronger rotocast A356-T6 alloy.
Are 706 heads better than 243 heads?
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.
What LS engine has 317 heads?
LQ4 engines received the Generation III 317 V8 head in 2001. It has cathedral shaped intake ports and D shaped exhaust. Its large combustion chamber results in lower compression ratios.
What are 241 heads?
The 241 head is a stock ls1 head it was on the f bodys and also on the ls1 vettes. They were produced between 2000 and 2003. they are the same as the 853, the 853 was made from 1997 to 2000.
What are LS6 heads?
The LS6 cylinder heads are a direct bolt-on, and completely interchangeable with our original LS1's.
What is the LQ4 engine?
The LQ4 is a 6.0L LS (Gen. 3) small block engine used in GM trucks between 1999 and 2007. For marketing purposes, it was also known as the Vortec 6000.
Are 799 heads good?
The 799 heads offered the most flow, bettering the 706 heads by as much as 20 cfm at some lift points. The chamber volume on the 799 heads was within 2.5 cc's of the 706 heads, but the dyno indicated this did not translate into power on our test engine.
What degree are LS heads?
The stock small-block angle is 23 degrees but as the angle approaches true vertical, the port flow improves. This is why the original production LS heads use a 15-degree valve angle.
Are cathedral heads better?
It is interesting to note that the cathedral-port heads offered better low-speed power and produced peak torque lower than the LS3 heads (irrespective of cam choice).
What engines came with 706 heads?
The LS 706 Heads wound up on different models of the Chevy family and fit with the high-performing LM7, LR4, and LM4 5.3 engines. The engine specialists have remanufactured these high-geared cylinder heads at a much more affordable cost and make them the best-performing, cathedral-port factory heads out in the market.
How much HP will Vortec heads add?
Most of these small block Chevy heads offer a power increase of around 40 hp, and even the iron Vortec heads were worth 20 hp over stock. The two best small block Chevy heads in terms of peak horsepower were worth more than 60 hp.
Do aluminum heads make more power?
Aluminum heads will dissipate heat faster. This allows for higher Compression Ratios with less risk of Detonation. The cooler head also delivers a cooler air/fuel mixture to the combustion chamber. Cooler air is denser and can make more power.
How much horsepower do performance cylinder heads add?
How much HP do heads add? Depending on your cam, you can gain anywhere from 40-70hp. Cam and heads can gain you 100+hp.
What LS motor has 823 heads?
823 heads are the l92 or ls3 heads.
What did 862 heads come on?
The 862 heads are on the GM's LM7 engines. The cylinder heads are designed with aluminum materials with a 61cc combustion chamber volume. They also come with a cathedral-shaped intake port and an oval exhaust port.
