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.
Does porting increase fuel consumption?
It enables your heads to flow more air….which means more fuel. Port matching is meant to smooth the flow of air as it transitions from the intake to the cylinder heads. It too leads to better airflow and more fuel.
Are 317 heads better than 706?
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 LS heads flow 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.
What do 317 heads flow?
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….317 Heads.
| 317 6.0L Truck Castings | ||
|---|---|---|
| Valve Size: Intake – 2.00, Exhaust – 1.55 | ||
| Lift | In. | Ex. |
| 0.050 | 33.3 | 24.5 |
| 0.100 | 63.4 | 54.2 |
Are 317 heads aluminum?
These heads came on low-performance 6.0-liter truck engines in two variations: “873” cast iron (1999–2000) and “317” aluminum (2001+).
What did 317 heads come on?
6.0L truck engines
According to Internet folklore, the 317 heads used on the 6.0L truck engines share the intake port design with the 799 (243) heads.
How much does it cost to get cylinder heads ported?
The cost for the procedure can vary widely from as little as $200 to more than $2000 dollars. A Stage III port and polish, however, is generally the best value and provides the most performance for your money. This type of port and polish costs about $500, depending on the type of vehicle you have.
How many cc are 317 heads?
71.5 cc’s
See all 18 photos The big-boy award went to the 317 (6.0L truck) heads, as the chamber volume measured a whopping 71.5 cc’s. The 317s shared the valve sizing with the 241 and 799 heads, and was said to share the intake port design with the 799/243 heads.
Is porting and polishing worth it?
In fact, a good port and polish job adds an additional 10 percent in both horsepower and in fuel economy, so it’s worth it. Start by cleaning the ports and then painting them with layout fluid. Place the high-performance intake manifold gaskets and exhaust gaskets in place and secure them with the bolts or nuts.