From what I got from the dimple port video, I think smooth on the areas where flow is fast, (the high velocity regions) having the port smooth, like a 220 finish or so, with it rougher on the slow areas like the first portion of the floor, so smooth on the top and the side, and the last 1/3 of the port at the short turn, 220-320 is plenty smooth for a port, but I have my exhaust and chamber looking like a mirror, I used 1200 grit diamond paste on the chamber and piston! If nothing else, it looks awesome! Maybe it will reflect heat, and prevent carbon sticking!
The dimples, or whatever method, other than smooth, are a way to make the air flow to stick/follow the wall/geometry, especially the on the short side, by disrupting the laminar flow. The laminar flow is the fastest, but it will follow only the straightest path and become very upset, if disturbed.. I don't think it's well known, the full effect, maybe has something to do with the harmonics of the intake, sometimes it will improve the mixture, sometimes not. The only thing that is known is the the mirror finish on the chamber and piston will end up loosing a chunk of carbon, at a random time, with rather nasty results..
Polishing any part of the heads internally, does nothing for power. Regardless of theories, it does none of that. Carbon sticks to the material, not the finish. It doesn't have to be aesthetically pleasing to make power.
You're the only other person I've heard talk about sanding that parting line in the short side radius after a head's been CNC ported my boss taught me that up at SD performance about a decade ago and I saw how well that can work and so I've done it ever since but it's very interesting to hear somebody else say that from my experience that I've seen Short side radius does not like to have anything abrupt especially in the Apex jmho
I never thought that a super smooth surface would loose flow!!!! This just goes to show that there is a technique for all heads. I learn a lot on this channel.
@@WeingartnerRacing that’s what I was thinking but I just had it backwards!!!! So would using a round flapper wheel with 120 be better on the short turn?
Great video Eric! When you roughed up the port floor, was it in any particular direction-were the sanding marks across the port floor 90degs to flow? I visualize sanding marks 90deg to flow creating eddies that help turn the air along the port's short side. Also, when you fill the port floor, could you flow a raised short side port that tapers to the original factory /as cast opening. Thank you.
Interesting! So what about fuel and suspension, at what point do smooth surfaces become detrimental? In these fuel injected engines with atomization occurring more precisely is there such a thing as fuel dropping out of suspension? Id guess that the boundary layer where the surfaces have been smooth added to more of a laminar flow at that particular cross section? Thanks dude, great work, thanks for sharing with us!!!
Would it be possible to set the head on a fixture of some kind and pump polishing compound through it? Some light grit stuff that flows easy. Example being set the head on a trough or large bucket combustion side down, set a pump to pull from the trough/bucket up through the intake port, back down into the trough. Like a fountain.
@@WeingartnerRacing do you use anything on a normal basis? I see that’s there’s several options but I don’t know if the people recommending them are as good as you are.
@@WeingartnerRacing Yes, same here! Really need to know what epoxy I can safely use in the head to fill and EGR port on exhaust side (it's huge) and small return C shaped openings on each port where the intake manifold flows the EGR back into the intake side of the head?
Always thought dimples reduced flow simply because of the drag & unwanted turbulence they create. I mean if you look inside a jet or rocket engine all the passage ways are smoothed out & shaped to reduce unwanted turbulence, any drag in the wrong area will reduce overall flow.
If your port has a short side issue, can you correct it with epoxy and actually use it on the street or track? Just thinking about that, it doesn’t seem like a good idea. I would think welding deep in the port like that would be really hard to do. I guess this would apply mostly to an aftermarket head like you’re working on because it’s not likely a stock head would be too big. So is epoxy a research only tool, or can you run it that way?
Using epoxy in the intake port has been and will continue to be done, and run that way successfully. When porting, you try not to use it, but some designs require it. Yes it can be run safely, and not just for design. It is mostly used for design because it beats having to weld and grind all the time just to test.
I'm not Eric, but I have used Petit Paint's _A-788 Splash Zone_ and found it excellent. It is just about as permanent as anything shy of welding, and I used it to move ports on an old GSXR1100(SACS engine) that went a timed 200 mph (which is a pretty serious effort in one of those old oil coolers. Lots of guys drill dowels/stud holes in head(being careful not to hit water) and that almost certainly helps in permanence, but I didn't find it necessary.
Can you please do me a favor!?!?!? Do all the good stuff onto 1 port. So dimple the long back side, smooth out the short side, do everything you found out to see if that will make the LS3 head flow over 400cfm
@@WeingartnerRacing have you ever tried? If so?! What results did you find? Thanks for your reply. You do interesting work. I have a theory on what you are doing. In part of your video you mentioned polishing the bottom floors of exhaust ports. But not the top or sides. I was looking at camera views inside the heads. What if you polished the top and bottom and left the sides? Reason being; the explosion in the chamber blasts upward then down and out. Just seems rational to smooth the top as well. Keep us informed. Good work!
I know you’re over the dimple port process and probably think it’s a fad. I’m inclined to agree with you to a small degree. But, I’d really like to see you fill in that last port with modeling clay, then pull it out and see if you can get similar results with dimpling the floor on that same port, and maybe taper it towards the part where you dropped the area on the short side. The eddies that the dimples produced seem like they’d serve as a much less risky alternative to epoxy. Probably not as good, but I’d like to know the trade off.
The dimples will determine the flow to follow the surface longer, if curved. There is no down side, even if the speed will slightly slow down, but the benefits are worth it. Some are speaking about wall wetting, with dimples, but if so, the problem is generated from other reasons, mainly too much porting. The fact is, that the air is bouncing around, forward and backward, exactly as a spring and may be that the dimples are smoothing out those harmonics. The back flow, from the inside of the cylinder is another thing that comes into play...Pp
That dimpled port is ridiculous, exactly as that epoxy velocity port or whatever. Flowing a head is misleading, nice but if not backed up by a Dyno sheet, remains only numbers..
I think the port liked the widened short side to throat entry & sloap. Roughness makes the ports basically smaller and smoothing it reduced the boundary later increasing the port size/ volume. Seems your on the right track to hit 390 plus CFM. Excellent work and very interesting. Be neat to see iff the guide reduction picks-up flow.
You need to show me the messed up way of making more flow so I can go to my dad's house tell him I am going to make more horses and he is like your the dumbest shit in the world just to prove him wrong would make my day
@@WeingartnerRacing thank you so much for all that you do Eric, it’s very much appreciated as a hobbyist who loves to porting motorbike heads. As I do no actual flow bench testing you validate a lot of my ideas even though every scenario is not the same because of different heads it is still helpful and just enjoyable to watch the journey.
CNC snob, where they're only as good as the program writer and setup machinist. Even "some" of the high profile companies don't touch off or use probes for core shift...
I typically don’t put it in customers heads because most don’t want to take the risk of epoxy coming out. Most are also not competing in a na class that is so competitive to require porting.
You really need to watch my other videos. I have explained many times why it is not. In summary it’s about port stability of the air. The flowbench doesn’t move as much air as a real engine.
Oh, I am very interested in the epoxied ports. This is getting fun.
Thanks for taking time and showing us! 👌🏼
From what I got from the dimple port video, I think smooth on the areas where flow is fast, (the high velocity regions) having the port smooth, like a 220 finish or so, with it rougher on the slow areas like the first portion of the floor, so smooth on the top and the side, and the last 1/3 of the port at the short turn, 220-320 is plenty smooth for a port, but I have my exhaust and chamber looking like a mirror, I used 1200 grit diamond paste on the chamber and piston! If nothing else, it looks awesome! Maybe it will reflect heat, and prevent carbon sticking!
The dimples, or whatever method, other than smooth, are a way to make the air flow to stick/follow the wall/geometry, especially the on the short side, by disrupting the laminar flow.
The laminar flow is the fastest, but it will follow only the straightest path and become very upset, if disturbed..
I don't think it's well known, the full effect, maybe has something to do with the harmonics of the intake, sometimes it will improve the mixture, sometimes not.
The only thing that is known is the the mirror finish on the chamber and piston will end up loosing a chunk of carbon, at a random time, with rather nasty results..
Polishing any part of the heads internally, does nothing for power. Regardless of theories, it does none of that. Carbon sticks to the material, not the finish. It doesn't have to be aesthetically pleasing to make power.
You're the only other person I've heard talk about sanding that parting line in the short side radius after a head's been CNC ported my boss taught me that up at SD performance about a decade ago and I saw how well that can work and so I've done it ever since but it's very interesting to hear somebody else say that from my experience that I've seen Short side radius does not like to have anything abrupt especially in the Apex jmho
I never thought that a super smooth surface would loose flow!!!! This just goes to show that there is a technique for all heads. I learn a lot on this channel.
The smoother grit gained flow not lost it. You have it reversed.
*Dry Flow
@@WeingartnerRacing soley depending on the head design not every head digs a super slick port
@@WeingartnerRacing that’s what I was thinking but I just had it backwards!!!! So would using a round flapper wheel with 120 be better on the short turn?
@@vortecturbo No head does.
I hope the LT6 gets popular enough to see one on here!
Go 100 grit on short side and try it.
Great video Eric! When you roughed up the port floor, was it in any particular direction-were the sanding marks across the port floor 90degs to flow? I visualize sanding marks 90deg to flow creating eddies that help turn the air along the port's short side. Also, when you fill the port floor, could you flow a raised short side port that tapers to the original factory /as cast opening. Thank you.
Interesting! So what about fuel and suspension, at what point do smooth surfaces become detrimental?
In these fuel injected engines with atomization occurring more precisely is there such a thing as fuel dropping out of suspension?
Id guess that the boundary layer where the surfaces have been smooth added to more of a laminar flow at that particular cross section?
Thanks dude, great work, thanks for sharing with us!!!
I’m only showing the effect of surface finish on flow. Wet flow is another story.
THANK YOU
I expect big results from raising the short side floor.
After you raise the floor what happens if you raise the port ceiling
Thanks so much for answering the CNC clean up question!
So what hap if you polish and diple the slow air areas?
Would it be possible to set the head on a fixture of some kind and pump polishing compound through it? Some light grit stuff that flows easy.
Example being set the head on a trough or large bucket combustion side down, set a pump to pull from the trough/bucket up through the intake port, back down into the trough. Like a fountain.
Why? Huge waste of time and energy. Just sayin.
Do you do any ceramic coatings??? Or have you??
No. I haven’t messed with them.
Id be frustrated too using that flashlight... lol im a light snob though
Light snobs unite
Eric, do you think port surface texture matters in a forced induction motor? BTW, your video's are fascinating.
That’s great gains for something so small. What Epoxy do you use?
This is jb weld steel stick. It’s really just for quick research work.
@@WeingartnerRacing do you use anything on a normal basis? I see that’s there’s several options but I don’t know if the people recommending them are as good as you are.
@@WeingartnerRacing Yes, same here! Really need to know what epoxy I can safely use in the head to fill and EGR port on exhaust side (it's huge) and small return C shaped openings on each port where the intake manifold flows the EGR back into the intake side of the head?
Always thought dimples reduced flow simply because of the drag & unwanted turbulence they create. I mean if you look inside a jet or rocket engine all the passage ways are smoothed out & shaped to reduce unwanted turbulence, any drag in the wrong area will reduce overall flow.
It's not all about a flow bench. Along with flow you gotta have fuel atomization which requires a surface course enough for the fuel to cling to..
Dimples do nothing. Theory and reality are two different things. Just sayin.
If your port has a short side issue, can you correct it with epoxy and actually use it on the street or track? Just thinking about that, it doesn’t seem like a good idea. I would think welding deep in the port like that would be really hard to do. I guess this would apply mostly to an aftermarket head like you’re working on because it’s not likely a stock head would be too big. So is epoxy a research only tool, or can you run it that way?
Using epoxy in the intake port has been and will continue to be done, and run that way successfully. When porting, you try not to use it, but some designs require it. Yes it can be run safely, and not just for design. It is mostly used for design because it beats having to weld and grind all the time just to test.
What kind of epoxy do you use? I have a Ford 240 head with very deep divots in the roof I want to smooth out without have to weld.
I'm not Eric, but I have used Petit Paint's _A-788 Splash Zone_ and found it excellent. It is just about as permanent as anything shy of welding, and I used it to move ports on an old GSXR1100(SACS engine) that went a timed 200 mph (which is a pretty serious effort in one of those old oil coolers. Lots of guys drill dowels/stud holes in head(being careful not to hit water) and that almost certainly helps in permanence, but I didn't find it necessary.
@@ToddWright2 splash zone for sure aka (green death) been using ot for years. Need to clear coat it with methanol fuel use though.
Third for Splash Zone.
Lepo uradjeno
Are those brass or copper valve guides?
Can you please do me a favor!?!?!? Do all the good stuff onto 1 port. So dimple the long back side, smooth out the short side, do everything you found out to see if that will make the LS3 head flow over 400cfm
Better V.E. doesn't always show up on bench test.
I agree. I’m just showing people information. They can do what they want with it.
Do you groove the top side of your valves? Old trick used to gain power.
No
@@WeingartnerRacing have you ever tried? If so?! What results did you find? Thanks for your reply. You do interesting work. I have a theory on what you are doing. In part of your video you mentioned polishing the bottom floors of exhaust ports. But not the top or sides. I was looking at camera views inside the heads. What if you polished the top and bottom and left the sides? Reason being; the explosion in the chamber blasts upward then down and out. Just seems rational to smooth the top as well. Keep us informed. Good work!
@@ricklodestein1101 ahh, the old "powre ringz" myth
@@GarcBomber who says it's a myth? Look up results from those who have proven it..
I know you’re over the dimple port process and probably think it’s a fad. I’m inclined to agree with you to a small degree.
But, I’d really like to see you fill in that last port with modeling clay, then pull it out and see if you can get similar results with dimpling the floor on that same port, and maybe taper it towards the part where you dropped the area on the short side.
The eddies that the dimples produced seem like they’d serve as a much less risky alternative to epoxy. Probably not as good, but I’d like to know the trade off.
The dimples will determine the flow to follow the surface longer, if curved. There is no down side, even if the speed will slightly slow down, but the benefits are worth it.
Some are speaking about wall wetting, with dimples, but if so, the problem is generated from other reasons, mainly too much porting.
The fact is, that the air is bouncing around, forward and backward, exactly as a spring and may be that the dimples are smoothing out those harmonics.
The back flow, from the inside of the cylinder is another thing that comes into play...Pp
148👍's🆙 thanks for sharing
could it be the 60 grit is letting you know that your dimples are too low or too deep maybe with the 60 grit is better than the dimples.
That dimpled port is ridiculous, exactly as that epoxy velocity port or whatever.
Flowing a head is misleading, nice but if not backed up by a Dyno sheet, remains only numbers..
I’m just doing what people asked to be done. I’m giving information people can do what they want with it.
I think the port liked the widened short side to throat entry & sloap. Roughness makes the ports basically smaller and smoothing it reduced the boundary later increasing the port size/ volume. Seems your on the right track to hit 390 plus CFM. Excellent work and very interesting. Be neat to see iff the guide reduction picks-up flow.
You need to show me the messed up way of making more flow so I can go to my dad's house tell him I am going to make more horses and he is like your the dumbest shit in the world just to prove him wrong would make my day
Eric your stuck in the 90s when it comes to cylinder heads and so are so many other quote professionals nether the less still great videos
Please expand on that.
@@WeingartnerRacing thank you so much for all that you do Eric, it’s very much appreciated as a hobbyist who loves to porting motorbike heads. As I do no actual flow bench testing you validate a lot of my ideas even though every scenario is not the same because of different heads it is still helpful and just enjoyable to watch the journey.
CNC snob, where they're only as good as the program writer and setup machinist. Even "some" of the high profile companies don't touch off or use probes for core shift...
Third hah ha!
You don't speak like you do much epoxy except for prototype stuff ...do not suggest that as a way to race a head even if care is taken to install it ?
I typically don’t put it in customers heads because most don’t want to take the risk of epoxy coming out. Most are also not competing in a na class that is so competitive to require porting.
Why flow test anything over .600 lift? These are useless numbers.
You really need to watch my other videos. I have explained many times why it is not. In summary it’s about port stability of the air. The flowbench doesn’t move as much air as a real engine.