i have a ls1 5.7 local performance shop recommended 862 heads that are worked, the offer 243 heads also same work done to them, which is going to make more power and estimated by how much, how much difference is raising the compression with the 862 heads going to make?
Compression is misleading, for ever full number of compression say 9.0-1 to 10.0-1 only changes power 4%. Cylinder head flow trumps a small bump in compression. Either head 862 or 243/799 will bump your compression compared to the factory LS1 heads which have huge 71+ cc chambers. Compare the flow numbers and price differences between the two options and pick the one that fits the budget. Naturally the 243/799 heads are better from the start so that’s worth mentioning, but a good flowing 862 is a great option too! JD
I ported my 862's for the larger valves that come with the LQ4. When I measured mine, I came up with 68cc for each cylinder, does that make sense? I did a fair bit of deshrouding the valves. Mine also went to a machine shop, but I asked them to only clean them up. I think the guy said me might have taken off 0.005. I'm by no means a pro at porting, but I really wanted to do it myself because even if I don't do it all that great, I know that I tried. Your videos have been very helpful explaining the process (I did the oil pump also)
Thank you! From my testing the 862/706 heads come factory with 65cc chambers. It looks like you did a good job unshrouding adding 3cc. .0075” cut equals +- 1cc so only cutting .005” should reduce the chambers a little over 1/2 cc or .66cc It’s so rewarding to hear these videos helped you work through the porting process on the heads and oil pump! Thanks again I appreciate your support! JD
@@HeadFlowInc The engine used in 1990-1995 Corvette ZR-1 was titled the LT5. The engine was designed by Lotus alongside GM engineers. It has a plenum and (2) fuel injector runners that people port along with the heads. Several videos about the car and the engine on RUclips. ruclips.net/user/shortsD7RMQgsfh3Y?si=di9UdkxYNx78jvJ2
On these heads they weren’t wanting to surface anymore than required to make flat. They were going on a 5.3 w/ Summit forged pistons. My 862’s on my 4.8 have 61.0cc chambers and a SCR 9.51-1
Nolands Cylinder Heads near the Greyhound bus station down town KC right off I-49/71 hwy. But be prepared they have a 3-4 week turnaround time to get the heads done. 816.471.5167 South of KC just South of Belton, Mo. is Performance Machine 816.250.5532 1/2 mile North of Midway HS.
YOU HAVE BEEN MISSED GLAD TO HEAR YOUR VOICE
Thank you!
Just subbed. So happy to find your channel.
Here’s a more detailed video:
ruclips.net/video/4ToIc6FzPF4/видео.html
@@HeadFlowInc thank you !!
I plan on going through your videos now that I found your channel. I'm here to learn. Safe Travels!!
Great Video's. I have a 5.3 and wanting to have some 862's done for it. Where are you located?
Butler, Mo. it’s straight South of Kansas City, Mo.
jeffdubray@gmail.com
i have a ls1 5.7 local performance shop recommended 862 heads that are worked, the offer 243 heads also same work done to them, which is going to make more power and estimated by how much, how much difference is raising the compression with the 862 heads going to make?
Compression is misleading, for ever full number of compression say 9.0-1 to 10.0-1 only changes power 4%.
Cylinder head flow trumps a small bump in compression. Either head 862 or 243/799 will bump your compression compared to the factory LS1 heads which have huge 71+ cc chambers.
Compare the flow numbers and price differences between the two options and pick the one that fits the budget.
Naturally the 243/799 heads are better from the start so that’s worth mentioning, but a good flowing 862 is a great option too! JD
I ported my 862's for the larger valves that come with the LQ4. When I measured mine, I came up with 68cc for each cylinder, does that make sense? I did a fair bit of deshrouding the valves. Mine also went to a machine shop, but I asked them to only clean them up. I think the guy said me might have taken off 0.005. I'm by no means a pro at porting, but I really wanted to do it myself because even if I don't do it all that great, I know that I tried. Your videos have been very helpful explaining the process (I did the oil pump also)
Thank you! From my testing the 862/706 heads come factory with 65cc chambers. It looks like you did a good job unshrouding adding 3cc.
.0075” cut equals +- 1cc so only cutting .005” should reduce the chambers a little over 1/2 cc or .66cc
It’s so rewarding to hear these videos helped you work through the porting process on the heads and oil pump!
Thanks again I appreciate your support! JD
Will the e1254p camshaft work well with a 10:1 lq9 looking for a lot of low end power?
The main thing is calculating your dynamic compression ratio, and making sure you don’t go too high if you’re planning on running pump gas
Have you ever done any porting work on 90-95 LT5?
There’s videos of a set of 90’s LT1 heads on my channel, I’ve never heard of LT5 heads. There was a HP LT4 heads on a Corvette
@@HeadFlowInc The engine used in 1990-1995 Corvette ZR-1 was titled the LT5. The engine was designed by Lotus alongside GM engineers. It has a plenum and (2) fuel injector runners that people port along with the heads. Several videos about the car and the engine on RUclips. ruclips.net/user/shortsD7RMQgsfh3Y?si=di9UdkxYNx78jvJ2
What static compression are you setting it at?
On these heads they weren’t wanting to surface anymore than required to make flat. They were going on a 5.3 w/ Summit forged pistons.
My 862’s on my 4.8 have 61.0cc chambers and a SCR 9.51-1
What machine shop do you recommend in the metro area?
Nolands Cylinder Heads near the Greyhound bus station down town KC right off I-49/71 hwy. But be prepared they have a 3-4 week turnaround time to get the heads done. 816.471.5167
South of KC just South of Belton, Mo. is Performance Machine 816.250.5532
1/2 mile North of Midway HS.
@@HeadFlowInc awesome. Thanks for the info.
👍
How can we get in contact with you for a 862 quote sir🙏🏼
Message
jeffdubray@gmail.com
Got any big valve 705/862
Ready to go i need a set for a ls1
Unfortunately I’ve used all my cores, currently don’t have any. Sorry JD
@@HeadFlowInc
I haves some 243s on the shelf if you have time for them.
I got backed up on my gen three 5.3 build 😔
Stay consistent, try to get one task done every day, big or small. Hang in there you’ll get there! JD
I measured mine and got 63 cc