I just saw a previous video that says you are here in Kansas City. I am currently doing a full 5.3 rebuild. When installing my valves in my brand new heads is there something I should be doing like sending them off to have a valve job done if so is there a company that you would recommend to me?
David Painter Hey David it depends on a couple factors. 1. You would need to put each valve back into its original position. If you didn’t organize the valves during disassembly then it may be necessary to get a valve job. I’ve never tried putting used mix-matched valves in a used head, maybe you could lap the valves to get them to seal? I lap all valves so I know they will seal. 2. Condition, are the valves pitted or showing damage? Assembly: *Clean out the guides with a brush really well and Lube with oil before final assembly. (Never use thick engine assembly lubes in the guides) *Lap all the valves & wash again *Verify the installed height on the springs, specifically if you have a valve job done. *If the heads will sit a long time I lightly grease the the seats. I use Performance Machine near Cleveland, Mo. but Nolands is very good but sometimes takes longer to get to back. I do not recommend Precision Crankshaft in Lees Summit, Mo.
Welfare Wagon We’re kind of “Trackless” since KCIR closed, generally we go to MoKan if we want to run the 1/4 mile or go up to Osborn, Mo. to US36 if we want something closer but it’s 1/8th mile only. The new 1/4 mile track is supposedly opening late Summer 2019 near Grain Valley? Fingers crossed, it’s supposed to be an NHRA sanctioned track. Iirc Cool G-body wagon! I’ll have to check out your channel! 👍
Andrew SS I now buy all my burrs off eBay, I’ve found buying from Cornwell, Fastenall etc is just too expensive. Also having long reach burrs come in very handy! 👍 JD
Good tutorial, this may be a dumb question, can I apply the same exhaust port, and swirl ramp cuts and blends to 317 heads. I will be running 4cc dome pistons 11:1 comp., no boost or NOS .
Brooklyn202 Yes, this covers all the cathedral port heads with the swirl ramp. Be very careful when working the bowl cuts, stay away from the sealing surface/angle! On the exhaust exit, make sure you stay inside size of the opening of the exhaust manifolds/headers. Check out Step 3 I posted today! 👍
is the narrowest point in the throat where to properly measure throat percentage? Is the bottom vertical area of the hardened insert considered the throat? or is the throat actually lower below the hardened insert? I currently have a set of bbc oval ports where the bowl area is flush with the hardened insert which is measuring at 92.5-92.6 percent but it gets wider below the insert.
Interesting, most porters use the 89% throat on the intake valve. Sometimes when you get the final blend and texture it may be closer to 90% Very few porters recommend going above 91% because the bigger you go the flow can suffer and the insert/seat gets thinner. Sometimes you can experiment with up to 92.4% by testing different valve sealing angles to get the best flow, which requires a flow bench for verification. The throat is the bottom of the seat below the sealing angle, the bowl is actually the area below the seat to the guide boss and can be slightly larger to help get the incoming charge to a better angle depending on the head. I hope this helps! JD
Too big can hurt flow, there’s a point of degraded angles and flow. Technically the bowl area should be slightly larger than the throat. Also if there’s a port bias enhancement of the wider side is preferred.
The throat on the 862/706 heads is big to start with. 92%. Take your time no rushing. Just do your guide boss shaping and make it blend, 60-80 grit finish in the intake ports.
I have set of the 799s where's the best area for home port to free up any restricted areas on intake-exhaust runners.not looking to match your work but I'd be happy with any hp gain
Marty Burden 100% the bowl cut and blend gives the most gain! After setting the bowl reshape/reduction of the valve guide boss. Create some templates so you can have consistent results. Intake bowl I like 89-90% of the valve size, with this being your first time you may want to be conservative so you don’t get too close to the sealing angle on the seat. For a 2.00” valve see how a 1.780” or 1.790” fits. You can use a 1.800” if your confident/careful. Exhaust side I use 86-87%,of the valve size: with a 1.55” valve make a 1.333” or a 1.345” template. Note: When blending the bowl cut to the ports try not to remove much material behind the guide and don’t change or dig into the short turn only blend to the existing radius/turn. Thanks for watching Good luck take your time you can do this! JD
Hi there from Australia I have a ls 1 5.7 with 853 heads I'm putting it in a jk wrangler I'm after good to mid range power could you tell me if I should run different heads and should I do any port work thanks any information would be appreciated
corey oryan The 853’s are basically like a 241 head if I remember correctly. I’d think you would want torque and mid-range, so a good bowl cut percentages and valve job would work great! Your heads already have +- 200cc intake runners with a swirl ramp to help torque with velocity. I’m not familiar with the octane of the fuel in Australia, but having the heads surfaced .020” would give you a small increase in Compression which will help Low speed torque and mid-top end power. Intake bowl 89% Exhaust bowl 87% Valve guide reduction would be optional, it will add a little volume to the port. Without seeing how you’re going to drive most of the time it’s difficult to say what’s needed. It’s tempting to say a good set of 862 heads would work great with a clean up with performance valve job and the bowl cut percentages. This option would raise the Compression requiring decent octane fuel. But the 862’s are great Torque and midrange heads that use a smaller 1.89” intake valve with the same 1.55” exhaust valve as the 853’s. Interesting hearing from you, good luck on your project and thanks for watching! JD
corey oryan Switching to the 862 heads would give you +- .5 increase in Compression, up to a real 10.5-1 area. This one change should provide around a 4-5% power increase, as long as your fuel safely supports it. You could mill/surface the 853’s to get the higher Compression but bigger amounts cut off the deck side of the heads add issues with finding the correct pushrod length. My hope is you can build the power in the area you need it most without spending too much. 👍
HeadFlowInc thank you for your reply much appreciated you explain things properly most engine builders in australia keep this to themselves we have 91-95-98 octane I think it would be the same as the USA i will keep whatching your vids thank you
Marty Burden Most of the heads I work with are stock castings, I wouldn’t be in business if you could only gain 10-15hp. Naturally the engine combo has a lot to do with the “Net” gain of porting heads; I’d expect 60-100+ HP. Cam timing is a big part of wanting to take advantage of the head flow. Thanks for watching and the feedback I appreciate it! Log on to CZcams without the app, this allows you to go back 7+ years and 400+ videos on my channel. Hopefully you subscribed! JD
Marty Burden I don’t get notified of subsequent replies, I just found this. I’ve had interest in testing back to back cylinder head only testing. It would be very interesting to see how head flow only affects the power, provided both sets of heads maintain the same size combustion chamber so the compression stays the same for each. People swap 243/799 heads over say 853/241 heads and report power gains, BUT there’s a bump in compression and more head flow with the 243/799 heads. 🤔🤔🤔 Thanks Marty for the question, I’m interested in finding out if/when I get an opportunity or can fund the testing myself. Thanks again! JD
Marty Burden I don’t get notified of subsequent replies, I just found this. I’ve had interest in testing back to back cylinder head only testing. It would be very interesting to see how head flow only affects the power, provided both sets of heads maintain the same size combustion chamber so the compression stays the same for each. People swap 243/799 heads over say 853/241 heads and report power gains, BUT there’s a bump in compression and more head flow with the 243/799 heads. 🤔🤔🤔 Thanks Marty for the question, I’m interested in finding out if/when I get an opportunity or can fund the testing myself. Thanks again! JD
I normally use air tools I like having better control over the burr speed. I did try to create a setup using a high speed diegrinder motor, 2x router speed controllers and a flex shaft from eBay. I didn’t like it and the collet on the flex shaft spins and is easy to burn yourself. I’d like to try one of the industrial wood working setups one day like the Fortner sp? It looks interesting! JD
@@HeadFlowInc thanks for the reply. Do you know if a set of 862s ported with a 2.0 intake valve unshrouded would have a better CD than a 799 on a 4.030 bore. Trying to decide what casting to use for turbo application in a heavy truck. I have both castings.
I’d look into both the Static Compression and more importantly the Dynamic Compression Ratio so you don’t exceed the fuel octane you intend to use. The LS engine camshafts are generally ground to build cylinder pressure with very little or even negative overlap; this can be bad when starting with higher SCR. Check out these free calculators remembering the max DCR for 93 octane is 8.70-1. As you can see the DCR is way different than the SCR most people are familiar with. I ran into this issue on my own 4.8 build because I hadn’t learned about DCR. My DCR is 9.00-1 which caused tuning issues because it was always on the edge of detonation so the computer was always pulling 4+ degree of timing. A camshaft with a later closing intake valve event can fix it but then you lose low end torque etc. JD
@@HeadFlowInc so a higher SCR would require you to run a lower boost pressure obviously to stay under the 8.70 DCR for pump gas but the motor would be more efficient out of boost and have more torque down low. The engine currently has rec port heads. Switching back to cathedral to gain low end torque but want to port to keep some of the power this thing has above 3500 now. I have 317s also but ill look into those calculations and see what comes up with the best combination with the 2 cams i have and different heads. Thank you! I appreciate you sharing your knowledge!
Measure the opening at the depth you need, ie the “Throat” is the transition from the seat into the port. The area below the throat is the “Bowl”. I apologize for confusing the terms, for decades I called everything the same thing, but you want to set the throat. Measure the throat then divide your measurement by the valve diameter. 1.785”/2.00”= .8925 or 89.25%
@@HeadFlowInc thanks for your reply i really appreciate but your video is too long and so much explanation thats why i forgot what you’re saying. but thanks i really appreciate your work. last question? is it okay if size diameter of valve guide side or bowl size is better than the throat? someone says is it better if the valve guide side is bigger than the valve throat percentage. thanks
Peter Fraumeni Interesting assessment, what parts do you feel is double speak? I reiterated information I feel is most important. Some viewers are more/less familiar with the porting process in general, so I try to explain as much as so everyone can follow along. Thanks for the feedback I appreciate it, hopefully the video was helpful to you. 👍. JD
Thanks for the info sir, working on my heads while listening to your instructions !
Good luck take your time!
Fantastic pointers and information
Thanx
There’s a lot of BAD information on you tube
I agree there’s some people a little cut happy. JD
Great video! Thank you very much!
I just saw a previous video that says you are here in Kansas City. I am currently doing a full 5.3 rebuild. When installing my valves in my brand new heads is there something I should be doing like sending them off to have a valve job done if so is there a company that you would recommend to me?
David Painter Hey David it depends on a couple factors.
1. You would need to put each valve back into its original position. If you didn’t organize the valves during disassembly then it may be necessary to get a valve job.
I’ve never tried putting used mix-matched valves in a used head, maybe you could lap the valves to get them to seal?
I lap all valves so I know they will seal.
2. Condition, are the valves pitted or showing damage?
Assembly:
*Clean out the guides with a brush really well and Lube with oil before final assembly. (Never use thick engine assembly lubes in the guides)
*Lap all the valves & wash again
*Verify the installed height on the springs, specifically if you have a valve job done.
*If the heads will sit a long time I lightly grease the the seats.
I use Performance Machine near Cleveland, Mo. but Nolands is very good but sometimes takes longer to get to back.
I do not recommend Precision Crankshaft in Lees Summit, Mo.
@@HeadFlowInc brand new in box heads and valves from Texas speed and performance. Can I just put those together without lapping? Thx for the response.
Seen that you posted a video of a car running at Mokan. I live very close to Mokan.
Welfare Wagon We’re kind of “Trackless” since KCIR closed, generally we go to MoKan if we want to run the 1/4 mile or go up to Osborn, Mo. to US36 if we want something closer but it’s 1/8th mile only.
The new 1/4 mile track is supposedly opening late Summer 2019 near Grain Valley? Fingers crossed, it’s supposed to be an NHRA sanctioned track. Iirc
Cool G-body wagon! I’ll have to check out your channel! 👍
Great explanation on the bowl porting percentages . Where do you buy the double cut burrs ?
Andrew SS I now buy all my burrs off eBay, I’ve found buying from Cornwell, Fastenall etc is just too expensive. Also having long reach burrs come in very handy! 👍 JD
Good tutorial, this may be a dumb question, can I apply the same exhaust port, and swirl ramp cuts and blends to 317 heads. I will be running 4cc dome pistons 11:1 comp., no boost or NOS .
Brooklyn202 Yes, this covers all the cathedral port heads with the swirl ramp. Be very careful when working the bowl cuts, stay away from the sealing surface/angle!
On the exhaust exit, make sure you stay inside size of the opening of the exhaust manifolds/headers.
Check out Step 3 I posted today! 👍
@@HeadFlowInc Thank you, I will watch this series a few times, and be too aggressive.
is the narrowest point in the throat where to properly measure throat percentage? Is the bottom vertical area of the hardened insert considered the throat? or is the throat actually lower below the hardened insert? I currently have a set of bbc oval ports where the bowl area is flush with the hardened insert which is measuring at 92.5-92.6 percent but it gets wider below the insert.
Interesting, most porters use the 89% throat on the intake valve. Sometimes when you get the final blend and texture it may be closer to 90%
Very few porters recommend going above 91% because the bigger you go the flow can suffer and the insert/seat gets thinner. Sometimes you can experiment with up to 92.4% by testing different valve sealing angles to get the best flow, which requires a flow bench for verification.
The throat is the bottom of the seat below the sealing angle, the bowl is actually the area below the seat to the guide boss and can be slightly larger to help get the incoming charge to a better angle depending on the head. I hope this helps! JD
@@HeadFlowInc do you think my engine would run alright with the throats opened up that much? Or would it run bad or have a big loss in power?
@@HeadFlowInc do you think it wouldnt matter as much how open the throat is under boost?
Too big can hurt flow, there’s a point of degraded angles and flow. Technically the bowl area should be slightly larger than the throat. Also if there’s a port bias enhancement of the wider side is preferred.
I bought a set of heads on the intake valve is already at 93% so I’m not going to touch that side of the valve
The throat on the 862/706 heads is big to start with. 92%. Take your time no rushing.
Just do your guide boss shaping and make it blend, 60-80 grit finish in the intake ports.
I have set of the 799s where's the best area for home port to free up any restricted areas on intake-exhaust runners.not looking to match your work but I'd be happy with any hp gain
Marty Burden 100% the bowl cut and blend gives the most gain! After setting the bowl reshape/reduction of the valve guide boss.
Create some templates so you can have consistent results.
Intake bowl I like 89-90% of the valve size, with this being your first time you may want to be conservative so you don’t get too close to the sealing angle on the seat. For a 2.00” valve see how a 1.780” or 1.790” fits. You can use a 1.800” if your confident/careful.
Exhaust side I use 86-87%,of the valve size: with a 1.55” valve make a 1.333” or a 1.345” template.
Note: When blending the bowl cut to the ports try not to remove much material behind the guide and don’t change or dig into the short turn only blend to the existing radius/turn.
Thanks for watching Good luck take your time you can do this! JD
Hi there from Australia I have a ls 1 5.7 with 853 heads I'm putting it in a jk wrangler I'm after good to mid range power could you tell me if I should run different heads and should I do any port work thanks any information would be appreciated
corey oryan The 853’s are basically like a 241 head if I remember correctly. I’d think you would want torque and mid-range, so a good bowl cut percentages and valve job would work great! Your heads already have +- 200cc intake runners with a swirl ramp to help torque with velocity.
I’m not familiar with the octane of the fuel in Australia, but having the heads surfaced .020” would give you a small increase in Compression which will help Low speed torque and mid-top end power.
Intake bowl 89%
Exhaust bowl 87%
Valve guide reduction would be optional, it will add a little volume to the port. Without seeing how you’re going to drive most of the time it’s difficult to say what’s needed.
It’s tempting to say a good set of 862 heads would work great with a clean up with performance valve job and the bowl cut percentages. This option would raise the Compression requiring decent octane fuel. But the 862’s are great Torque and midrange heads that use a smaller 1.89” intake valve with the same 1.55” exhaust valve as the 853’s.
Interesting hearing from you, good luck on your project and thanks for watching! JD
corey oryan Switching to the 862 heads would give you +- .5 increase in Compression, up to a real 10.5-1 area. This one change should provide around a 4-5% power increase, as long as your fuel safely supports it.
You could mill/surface the 853’s to get the higher Compression but bigger amounts cut off the deck side of the heads add issues with finding the correct pushrod length.
My hope is you can build the power in the area you need it most without spending too much. 👍
HeadFlowInc thank you for your reply much appreciated you explain things properly most engine builders in australia keep this to themselves we have 91-95-98 octane I think it would be the same as the USA i will keep whatching your vids thank you
Great videos..have ya dynoed to see what just porting stock heads can gain? I've been told like 10-15 hp
Marty Burden Most of the heads I work with are stock castings, I wouldn’t be in business if you could only gain 10-15hp. Naturally the engine combo has a lot to do with the “Net” gain of porting heads; I’d expect 60-100+ HP.
Cam timing is a big part of wanting to take advantage of the head flow.
Thanks for watching and the feedback I appreciate it! Log on to CZcams without the app, this allows you to go back 7+ years and 400+ videos on my channel. Hopefully you subscribed! JD
@@HeadFlowInc sry I should've said stock engine setup VS stock engine with ported stock head and cam and intake are huge part
Marty Burden I don’t get notified of subsequent replies, I just found this.
I’ve had interest in testing back to back cylinder head only testing. It would be very interesting to see how head flow only affects the power, provided both sets of heads maintain the same size combustion chamber so the compression stays the same for each.
People swap 243/799 heads over say 853/241 heads and report power gains, BUT there’s a bump in compression and more head flow with the 243/799 heads. 🤔🤔🤔
Thanks Marty for the question, I’m interested in finding out if/when I get an opportunity or can fund the testing myself. Thanks again! JD
Marty Burden I don’t get notified of subsequent replies, I just found this.
I’ve had interest in testing back to back cylinder head only testing. It would be very interesting to see how head flow only affects the power, provided both sets of heads maintain the same size combustion chamber so the compression stays the same for each.
People swap 243/799 heads over say 853/241 heads and report power gains, BUT there’s a bump in compression and more head flow with the 243/799 heads. 🤔🤔🤔
Thanks Marty for the question, I’m interested in finding out if/when I get an opportunity or can fund the testing myself. Thanks again! JD
what flex shaft rotary tool do you run?
I normally use air tools I like having better control over the burr speed.
I did try to create a setup using a high speed diegrinder motor, 2x router speed controllers and a flex shaft from eBay. I didn’t like it and the collet on the flex shaft spins and is easy to burn yourself.
I’d like to try one of the industrial wood working setups one day like the Fortner sp? It looks interesting! JD
@@HeadFlowInc thanks for the reply. Do you know if a set of 862s ported with a 2.0 intake valve unshrouded would have a better CD than a 799 on a 4.030 bore. Trying to decide what casting to use for turbo application in a heavy truck. I have both castings.
I’d look into both the Static Compression and more importantly the Dynamic Compression Ratio so you don’t exceed the fuel octane you intend to use.
The LS engine camshafts are generally ground to build cylinder pressure with very little or even negative overlap; this can be bad when starting with higher SCR.
Check out these free calculators remembering the max DCR for 93 octane is 8.70-1. As you can see the DCR is way different than the SCR most people are familiar with.
I ran into this issue on my own 4.8 build because I hadn’t learned about DCR. My DCR is 9.00-1 which caused tuning issues because it was always on the edge of detonation so the computer was always pulling 4+ degree of timing. A camshaft with a later closing intake valve event can fix it but then you lose low end torque etc. JD
@@HeadFlowInc so a higher SCR would require you to run a lower boost pressure obviously to stay under the 8.70 DCR for pump gas but the motor would be more efficient out of boost and have more torque down low. The engine currently has rec port heads. Switching back to cathedral to gain low end torque but want to port to keep some of the power this thing has above 3500 now. I have 317s also but ill look into those calculations and see what comes up with the best combination with the 2 cams i have and different heads. Thank you! I appreciate you sharing your knowledge!
how do i calculate bowl size percentage?
Measure the opening at the depth you need, ie the “Throat” is the transition from the seat into the port. The area below the throat is the “Bowl”. I apologize for confusing the terms, for decades I called everything the same thing, but you want to set the throat.
Measure the throat then divide your measurement by the valve diameter. 1.785”/2.00”= .8925 or 89.25%
@@HeadFlowInc thanks for your reply i really appreciate but your video is too long and so much explanation thats why i forgot what you’re saying. but thanks i really appreciate your work.
last question? is it okay if size diameter of valve guide side or bowl size is better than the throat? someone says is it better if the valve guide side is bigger than the valve throat percentage. thanks
bigger*
because it will create venturi effect to throat and valve.
excellent friend this work looks great I congratulate you would like to write by email
Good ideas on making templates for % but too much double speak babble makes the message difficult to follow.
Peter Fraumeni Interesting assessment, what parts do you feel is double speak?
I reiterated information I feel is most important. Some viewers are more/less familiar with the porting process in general, so I try to explain as much as so everyone can follow along.
Thanks for the feedback I appreciate it, hopefully the video was helpful to you. 👍. JD