Are 317 heads better than 706 heads?
The 317 heads flowed more than the 706 heads by as much as 20 cfm at some lift points. The peak flow numbers differed by just 7 cfm at 0.700 lift. What made the 317 heads both kissed and cursed was the combustion chamber size. The massive chamber volume of 71.5 cc’s put them a full 10 cc’s over the 706 heads.
What engines came with 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. Often used for turbo and supercharger applications.
Which stock 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.
Which heads are better 706 vs 862?
While 862 heads are sand cast, 706 heads are semi-permanent mold. Also, they have smaller combustion chambers, and the milling of the deck surface will allow a slightly higher compression ratio than the 706 heads. Except for this, there is only a negligible difference between 706 and 862 heads.
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’s better LQ4 or LQ9?
The ONLY difference between an LQ4 and LQ9 is the piston!
The LQ4 piston is dished where as the LQ9 is a flat-top increasing compression to 10:1, and HP to 345 factory. The LQ9 is a limited production engine and VERY desirable as it is the HO 6.0L and comes with a premium price.
Are 243 heads any good?
Of course, the 243 head is designed with a better casting which has a smaller chamber for more compression. They flow better and have the capacity to deliver more than 5% horsepower on flow alone. If you desire to perform a porting on your vehicle’s cylinder head, getting new 243 heads is perfect for the porting job.
How much are 317 heads worth?
$150-$200 for a nice used set.
Which LS motor is best for boost?
If you’re planning on boosting your project the 4.8L truck engine will be perfect for you. The 4.8L can take insane amounts of boost completely stock and will really perform well. If you don’t want a barebones 5.3L or 4.8L you could always step up to a 6.2L truck block which is based on the LS3 engine.
How much HP can a 6.0 LS handle?
If we were to run the 6.0L in stock trim, the resulting power output would be around 400 hp (on this dyno the way we test).
References:
- https://www.motortrend.com/how-to/surprising-hp-numbers-stock-ls-cylinder-head-test/
- https://www.fulcrumparts.com/new-gm-ls-317-head-6-0l
- https://www.lsenginediy.com/ultimate-ls-cathedral-port-cylinder-heads-guide/
- https://www.alliedmotorparts.com/blogs/news/are-862-heads-a-better-choice
- https://www.roadcartel.com/blog/are-706-heads-better-than-243-heads-2
- http://bdturnkeyengines.com/60l-lq9-vs-lq4
- https://rxmechanic.com/243-heads/
- https://www.yellowbullet.com/threads/whats-a-set-of-317-heads-worth.594477/
- https://performanceimprovements.com/blogs/news/which-ls-engine-should-you-swap-in-your-car
- https://www.motortrend.com/how-to/1711-how-much-boost-can-a-6l-ls-truck-short-block-take/