Polishing throttle body

[Timber0472]

First forgive me if this is posted in the wrong section. Not sure where to post.
I know this topic has been beat to death but I've never read anything about polishing runners/ throttle body exits. Many have stated that rough is better for atomization on head intake ports but I'm talking about the throttle body. Ive heard that with efi polished is better than rough due to the location of injectors. Is anything really getting atomized in an inch of travel? I would think that with an efi throttle body one would want as much air as quickly as possible to enter in the chamber.
With a carb it makes sense to have a slightly rougher surface to aid in mixing because of contact time.

I have no experience with this. Just curious about this topic. Hoping someone with knowledge will jump in.

[q1svt]

First forgive me if this is posted in the wrong section. Not sure where to post.
I know this topic has been beat to death but I've never read anything about polishing runners/ throttle body exits. Many have stated that rough is better for atomization on head intake ports but I'm talking about the throttle body. Ive heard that with efi polished is better than rough due to the location of injectors. Is anything really getting atomized in an inch of travel? I would think that with an efi throttle body one would want as much air as quickly as possible to enter in the chamber.
With a carb it makes sense to have a slightly rougher surface to aid in mixing because of contact time.

I have no experience with this. Just curious about this topic. Hoping someone with knowledge will jump in.

Attached is a picture of an HPI HD manifold... you can see that it does have a very smooth finish.  Not sure polishing will get you anything more.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB

[Timber0472]

First forgive me if this is posted in the wrong section. Not sure where to post.
I know this topic has been beat to death but I've never read anything about polishing runners/ throttle body exits. Many have stated that rough is better for atomization on head intake ports but I'm talking about the throttle body. Ive heard that with efi polished is better than rough due to the location of injectors. Is anything really getting atomized in an inch of travel? I would think that with an efi throttle body one would want as much air as quickly as possible to enter in the chamber.
With a carb it makes sense to have a slightly rougher surface to aid in mixing because of contact time.

I have no experience with this. Just curious about this topic. Hoping someone with knowledge will jump in.

Attached is a picture of an HPI HD manifold... you can see that it does have a very smooth finish.  Not sure polishing will get you anything more.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB

Ok. Yea didn't really think it would really do anything major for numbers. Just curious about the subject.
Thanks for the reply. That is a very smooth TB.

[q1svt]

Ok. Yea didn't really think it would really do anything major for numbers. Just curious about the subject.
Thanks for the reply. That is a very smooth TB.

HPI is one of the best HD TB's and the smooth finish is one of a number of things that helps the performance "numbers"   

polishing just isn't going to add more over their smooth finish...

[FlaHeatWave]

The Harley TBs  (both stock and SE 58mm) are quite rough, no where near as smooth as the HPI units. While doing the Heads for the 117 had the SE 58 polished and port matched,,, don't know what if any gains?? did not do any before / after testing to isolate...

On a different deal, I was told by Jamie that smoothing / polishing the "Y" area (stock / SE) showed the most gains...

[TorQuePimp]

 Polishing without  reshaping/porting is pointless

Polishing slows the air down...not alot but enough to hurt performance

Rougher the better 

[BUBBIE]

 

Some-what ROUGH tumbles/swirls the fuel mix into the cylinder... Been that way for me for Years...

IF different today in a smooth opinion, I don't care to differ... OLD School... Jerry Branch did both the Polishing of the ports/manifold BUT only needed Polished exhaust... IMO and memory...

signed....BUBBIE

[q1svt]

Polishing slows the air down...not alot but enough to hurt performance

Rougher the better 

I would be interested in the harley data that supports the statement?

We are talking about the TB & Manifold for EFI so they are a dry flow... not the head runners or ports.
There was not engine specifications provided, so how would you know what the cross-sectional dimensions are? Ruffing does increase the thickness of the boundary layer right? making the air think the cross-section is smaller and I guess would increase the air flow, but to much speed can be bad too right? don't most harley run undersize intake runner cross-section area do to limited space between the cylinders?
Wouldn't "rougher the better" cause turbulence in the TB & Manifold? And as the picture shows in the first response, the short side is pretty smooth...  isn't turbulence on the short side one of your worst enemies for good air flow?

My moneys on Jimmy and his research and development done for the HPI cable efi TB's 


Bubbie, dry and wet flow needs different things... I'm not a polish the intake manifold or TB guy, but a very fine finish I'm good with.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB.

[qtrracer]

Gotta say look at nature for guidance in these areas. For example see any birds with polished wings?

[FlaHeatWave]

The Harley TBs  (both stock and SE 58mm) are quite rough, no where near as smooth as the HPI units. While doing the Heads for the 117 had the SE 58 polished and port matched,,, don't know what if any gains?? did not do any before / after testing to isolate...

On a different deal, I was told by Jamie that smoothing / polishing the "Y" area (stock / SE) showed the most gains...

'Guess my nomenclature is off   my "polishing" should be substituted by smoothing,,, not polished as one would do with jewlers rouge,,, 'just smoothed,,, the same texture as the ported intake tracts...

[Timber0472]

 
This is getting interesting. I would think (which I seldom do) that if it's only air flowing 90% of the efi throttle passageway then the smoother the better. Does atomization occur there or more so in the head intake port? If that's the case then a smooth throttle body and rough intake port would make sense....but again I am by no means an expert in any of this. Just deducting from what has been stated so far.

[HD/Wrench]

Ok but is the flow really dry..  as these are pumping oil mist back into the manifold . Not a huge amount but we know that you can see it puff out the heads , so one would think this could effect it.

Back to the real world.. and just test it .

  I have found on a stock engine that polishing the stock FBW offers no gains in a Stage 1 and in stage II builds. Taken from the website that the customer bought the item . He also had me  tune his bike  He had this done with the ex and air cleaner, then "HE the customer " added a cam

  "includes cleanup and porting of the runner and manifold, contouring the transition around the injector ports, and matching the inlet radius to the air cleaner backing plate"


Well that guy had a intake leak. later on .  So he had me change the seals I asked him if he would mind if I kept the bike for an extra day to test.. On his it made no increase. Now I can see where a larger engine with more performance parts , larger T/B benefiting from this

[1FSTRK]

I think the problem with finding the correct answer is in asking the right question here.
There is improving flow, improving flow on a running engine, or improving hp output.
After that it will still be port and TB/Manifold subjective. As the finish changes so does the boundary layer and flow but as soon as it is not a straight tube then we have velocity and pressure variances as we change direction so we have changing needs when it comes to how we want to affect the boundary layer and flow.

Next we have how the cam and overall port speed effect the dynamic flow of the intake tract and after that we have the introduction of fuel and any oils that find there way into the system. Even with testing the needs will change as the build components change, I have seen something make a 6-8% increase in HP on a given build and not work on the next build with a different cam and exhaust.

The answer may be in the fact that we see one company selling a special texture treatment on the inside of their TBs and another equally successful company selling their TBs with a smooth machined finish and others range somewhere in between. Beyond using them as they come will require specific application testing that only a select few will do on a build specific basis but it is winter and too cold to ride so what else is there to discuss.

[rigidthumper]

I'm wanting to try this combo on a 117 next:
[smg id=2906]
[smg id=2907]
[smg id=2908]

[1FSTRK]

Back in the old days at least one porter I know of ran that finish all the way from the carb spigot to the back of the valve seat and it works great on the right high HP/CI builds.

[q1svt]

This is getting interesting. I would think (which I seldom do) that if it's only air flowing 90% of the efi throttle passageway then the smoother the better. Does atomization occur there or more so in the head intake port? If that's the case then a smooth throttle body and rough intake port would make sense....but again I am by no means an expert in any of this. Just deducting from what has been stated so far.

Looks like I broke a rule and the post was deleted... but it seems you may have seen it.
Google 'Moody Chart' providing information on flow & roughtness applied to Reynolds Number.

Yes, there are many documents about wall wetting and it's affect, but Harley's incredible SHORT intake track voids most of these papers... Injector firing on a closed valve too.  The question is If any fuel is on the wall how long (in time, millisec) does it take for the fuel to reach the cylinder? Since fuel droplets don't burn, it's important to get any fuel on the wall re-atomized... where many believe that it's important of doing it via the complete intake track.  But because HD track is so short almost all fuel will make it into the cylinder; if fuel running down the wall can be completely atomized within the last portion of the intake, why ruff it up the entire intake tract and deal with the issues the roughness causes?

just the thoughts of a HD dummy, but we have been testing the HPI cable manifold on & off for about 2 years, why? to apply the information gained to apply to a 70 year old shared runner head.  [HPI] Jimmy's done some very interesting things ( and NO, we're not going to share it).

[SP33DY]

There's more to gain with crisp back cuts and margins on the intake valves. In wet flow testing I have seen these help by acting to shear and atomize the fuel puddle so it mixes better with the air.

[jmorton10]

Back in the old days at least one porter I know of ran that finish all the way from the carb spigot to the back of the valve seat and it works great on the right high HP/CI builds.

I had a set of dual plug shovelheads reworked by Dave Mackie in 1983 for a wild stroker motor I had built at the time.  The intake finish looked just like that & worked very very well.  The exhaust port & combustion chamber where polished (of course that was not an fi motor back in those days)

~John

[TorQuePimp]

Polishing slows the air down...not alot but enough to hurt performance

Rougher the better 

I would be interested in the harley data that supports the statement?

We are talking about the TB & Manifold for EFI so they are a dry flow... not the head runners or ports.
There was not engine specifications provided, so how would you know what the cross-sectional dimensions are? Ruffing does increase the thickness of the boundary layer right? making the air think the cross-section is smaller and I guess would increase the air flow, but to much speed can be bad too right? don't most harley run undersize intake runner cross-section area do to limited space between the cylinders?
Wouldn't "rougher the better" cause turbulence in the TB & Manifold? And as the picture shows in the first response, the short side is pretty smooth...  isn't turbulence on the short side one of your worst enemies for good air flow?

My moneys on Jimmy and his research and development done for the HPI cable efi TB's 


Bubbie, dry and wet flow needs different things... I'm not a polish the intake manifold or TB guy, but a very fine finish I'm good with.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB.

If hpi's finish looked like the pictures posted by Ridgid thumper .....Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

Pretty sanded parts sell......Just like Branch polished nonsense did Back in the day

I've never seen properly shaped ports with a rough 35 grit finish or even a tooled or dimpled finish make less power....Workmanship matters here and making "Potty mouth"ked up looking ports that look like they were done with a mini hatchet......Isn't going to help either.....

I've got both  digital  velocity probe and a swirl meter on my bench......And finish does matter

[No Cents]

I'm wanting to try this combo on a 117 next:
[smg id=2906]
[smg id=2907]
[smg id=2908]

  very interesting looking port work there Robin.   

[rigidthumper]

You've seen similar, I'd wager

[No Cents]

 
   

[q1svt]

Polishing slows the air down...not alot but enough to hurt performance

Rougher the better 

I would be interested in the harley data that supports the statement?

We are talking about the TB & Manifold for EFI so they are a dry flow... not the head runners or ports.
There was not engine specifications provided, so how would you know what the cross-sectional dimensions are? Ruffing does increase the thickness of the boundary layer right? making the air think the cross-section is smaller and I guess would increase the air flow, but to much speed can be bad too right? don't most harley run undersize intake runner cross-section area do to limited space between the cylinders?
Wouldn't "rougher the better" cause turbulence in the TB & Manifold? And as the picture shows in the first response, the short side is pretty smooth...  isn't turbulence on the short side one of your worst enemies for good air flow?

My moneys on Jimmy and his research and development done for the HPI cable efi TB's 


Bubbie, dry and wet flow needs different things... I'm not a polish the intake manifold or TB guy, but a very fine finish I'm good with.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB.

If hpi's finish looked like the pictures posted by Ridgid thumper .....Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

Pretty sanded parts sell......Just like Branch polished nonsense did Back in the day

I've never seen properly shaped ports with a rough 35 grit finish or even a tooled or dimpled finish make less power....Workmanship matters here and making "potty mouth! " up looking ports that look like they were done with a mini hatchet......Isn't going to help either.....

I've got both  digital  velocity probe and a swirl meter on my bench......And finish does matter

It was a simple question: Got Data?  You do use those tools on harley heads and manifolds you port?

Not here to bash, but every time I've asked you for clarification you pass off this kind of nonsense...
I understand your a known porter and sell software, but your site(s) has smooth ports [Chev & Dodge non-hemi], the software doesn't include cal's for shared runner intakes like Harleys [harmonic wave or cross-section]...  When you used a 23* chevy inline valve head in another thread to explain valve sizing for a Harley crossflow head you're undermining your credibility...

I'm not expecting a technical response from you... but HTT is a place people try to get technical information SPECIFIC to Harleys 

FWIW, until you can show technically, how knowledge has evolved over Branch's smoother ports With/Specific to Harleys... OR Jimmy's HPI [he has good tools too] Your statement  "Just like Branch polished nonsense did Back in the day", you just joined the "Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

[TorQuePimp]

Polishing slows the air down...not alot but enough to hurt performance

Rougher the better 

I would be interested in the harley data that supports the statement?

We are talking about the TB & Manifold for EFI so they are a dry flow... not the head runners or ports.
There was not engine specifications provided, so how would you know what the cross-sectional dimensions are? Ruffing does increase the thickness of the boundary layer right? making the air think the cross-section is smaller and I guess would increase the air flow, but to much speed can be bad too right? don't most harley run undersize intake runner cross-section area do to limited space between the cylinders?
Wouldn't "rougher the better" cause turbulence in the TB & Manifold? And as the picture shows in the first response, the short side is pretty smooth...  isn't turbulence on the short side one of your worst enemies for good air flow?

My moneys on Jimmy and his research and development done for the HPI cable efi TB's 


Bubbie, dry and wet flow needs different things... I'm not a polish the intake manifold or TB guy, but a very fine finish I'm good with.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB.

If hpi's finish looked like the pictures posted by Ridgid thumper .....Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

Pretty sanded parts sell......Just like Branch polished nonsense did Back in the day

I've never seen properly shaped ports with a rough 35 grit finish or even a tooled or dimpled finish make less power....Workmanship matters here and making "potty mouth! " up looking ports that look like they were done with a mini hatchet......Isn't going to help either.....

I've got both  digital  velocity probe and a swirl meter on my bench......And finish does matter

It was a simple question: Got Data?  You do use those tools on harley heads and manifolds you port?

Yes i use both of those tools when im developing a new port...otherwise I really dont

Once a port is done....its been run thru its paces the only thing left to do is run it on a dyno and adjust....that has been done

Not here to bash, but every time I've asked you for clarification you pass off this kind of nonsense...
I understand your a known porter and sell software, but your site(s) has smooth ports [Chev & Dodge non-hemi], the software doesn't include cal's for shared runner intakes like Harleys [harmonic wave or cross-section]...  When you used a 23* chevy inline valve head in another thread to explain valve sizing for a Harley crossflow head you're undermining your credibility...

  The article written by larry M was based on the texture he uses on both intake manifolds and intake ports.....not specific to any one V-8

I also posted pictures of a late model hemi port with dimples and done with a narrow high helix burr

I dont sell software....I use quite a bit of it and for the most part not any that most shops use.....but they are starting to

  If i dont answer you I may not see what you have asked

I'm not expecting a technical response from you... but HTT is a place people try to get technical information SPECIFIC to Harleys 

FWIW, until you can show technically, how knowledge has evolved over Branch's smoother ports With/Specific to Harleys... OR Jimmy's HPI [he has good tools too] Your statement  "Just like Branch polished nonsense did Back in the day", you just joined the "Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

  My statement....nobody of any credibility polishes ports anymore...should tell you something

  Pretty finishing sells....thats my point

  Not bashing HPI im saying if they did finish the ports like pictured above there would be people who thought it was a bad thing....rest assured it is not

[hdtuner23]

Polishing slows the air down...not alot but enough to hurt performance

Rougher the better 

I would be interested in the harley data that supports the statement?

We are talking about the TB & Manifold for EFI so they are a dry flow... not the head runners or ports.
There was not engine specifications provided, so how would you know what the cross-sectional dimensions are? Ruffing does increase the thickness of the boundary layer right? making the air think the cross-section is smaller and I guess would increase the air flow, but to much speed can be bad too right? don't most harley run undersize intake runner cross-section area do to limited space between the cylinders?
Wouldn't "rougher the better" cause turbulence in the TB & Manifold? And as the picture shows in the first response, the short side is pretty smooth...  isn't turbulence on the short side one of your worst enemies for good air flow?

My moneys on Jimmy and his research and development done for the HPI cable efi TB's 


Bubbie, dry and wet flow needs different things... I'm not a polish the intake manifold or TB guy, but a very fine finish I'm good with.

Need to remember that most HD injectors fires on a closed intake valve, so fuel is sucked into the cylinder when the valve opens.  That's why the head runner and port needs to be ruff in places compared to the TB.

If hpi's finish looked like the pictures posted by Ridgid thumper .....Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

Pretty sanded parts sell......Just like Branch polished nonsense did Back in the day

I've never seen properly shaped ports with a rough 35 grit finish or even a tooled or dimpled finish make less power....Workmanship matters here and making "potty mouth! " up looking ports that look like they were done with a mini hatchet......Isn't going to help either.....

I've got both  digital  velocity probe and a swirl meter on my bench......And finish does matter

It was a simple question: Got Data?  You do use those tools on harley heads and manifolds you port?

Yes i use both of those tools when im developing a new port...otherwise I really dont

Once a port is done....its been run thru its paces the only thing left to do is run it on a dyno and adjust....that has been done

Not here to bash, but every time I've asked you for clarification you pass off this kind of nonsense...
I understand your a known porter and sell software, but your site(s) has smooth ports [Chev & Dodge non-hemi], the software doesn't include cal's for shared runner intakes like Harleys [harmonic wave or cross-section]...  When you used a 23* chevy inline valve head in another thread to explain valve sizing for a Harley crossflow head you're undermining your credibility...

  The article written by larry M was based on the texture he uses on both intake manifolds and intake ports.....not specific to any one V-8

I also posted pictures of a late model hemi port with dimples and done with a narrow high helix burr

I dont sell software....I use quite a bit of it and for the most part not any that most shops use.....but they are starting to

  If i dont answer you I may not see what you have asked

I'm not expecting a technical response from you... but HTT is a place people try to get technical information SPECIFIC to Harleys 

FWIW, until you can show technically, how knowledge has evolved over Branch's smoother ports With/Specific to Harleys... OR Jimmy's HPI [he has good tools too] Your statement  "Just like Branch polished nonsense did Back in the day", you just joined the "Guarantee there would be pictures all over saying how bad it is or how it's shoddy workmanship.

  My statement....nobody of any credibility polishes ports anymore...should tell you something

  Pretty finishing sells....thats my point

  Not bashing HPI im saying if they did finish the ports like pictured above there would be people who thought it was a bad thing....rest assured it is not

. The last manifold I just received from HPI...Sure looks CNC ported to me?