Author Topic: DYI Head Porting (Read 19258 times) Tweet

slatroni · « **on:** July 21, 2010, 06:48:06 PM »

Like most of the people on this sight, I like to do my own work. I got ahold of another stock head and I want to do a clean-up port job myself. Any tips or links that will help? I would kill to have one of the big name heads, but like everywere money is tight. I also got another set of stock cams to send out for regrind. How big can a regrind go?
Thanks!
Steve

All I need is 200hp!

jblankenship · « **Reply #1 on:** July 21, 2010, 09:41:21 PM »

I did mine, knocked all the casting marks down along sides of the runners, up at the valve seat where the port comes to the valve seat area there is a large ridge, blend that. I knocked the small humps down by the valve guides, then I just smooth it down until the rough casting is smooth. I stay away from reshaping or hogging out. I do also port match the intake boots. I also took out the 3 ridges in the tbs this time. Some pics:

jblankenship · « **Reply #2 on:** July 21, 2010, 09:46:57 PM »

jblankenship · « **Reply #3 on:** July 21, 2010, 09:48:45 PM »

another

jblankenship · « **Reply #4 on:** July 21, 2010, 09:50:12 PM »

back from being milled(thanks Rc's Performance)

jblankenship · « **Reply #5 on:** July 21, 2010, 09:52:14 PM »

combustion area cleaned and valve lapped back in

wildphil69 · « **Reply #6 on:** July 21, 2010, 09:55:53 PM »

looks like mine....did you weld the pair holes?

jblankenship · « **Reply #7 on:** July 21, 2010, 09:56:54 PM »

some more

jblankenship · « **Reply #8 on:** July 21, 2010, 09:57:42 PM »

last one

jblankenship · « **Reply #9 on:** July 21, 2010, 10:00:13 PM »

Quote from: wildphil69 on July 21, 2010, 09:55:53 PM

looks like mine....did you weld the pair holes?

No, but this head made 203 hp on Rc's Performance dyno at 68" on 93 pump gas, head milled .010", 395/378 webs, Je 12.3:1 drop ins, counter balance gear removed. I'm 195 unsuited and been 8.85 at 153 on it.

jblankenship · « **Reply #10 on:** July 21, 2010, 10:03:20 PM »

throttle bodies:

jblankenship · « **Reply #11 on:** July 21, 2010, 10:06:56 PM »

another 1

jblankenship · « **Reply #12 on:** July 21, 2010, 10:07:57 PM »

magus · « **Reply #13 on:** July 22, 2010, 07:28:19 AM »

I got mine apart for rebuild now. I plan on doing this soon also.

slatroni · « **Reply #14 on:** July 22, 2010, 08:47:38 AM »

Nice work! Thanks for the Pics!
Steve

Jonny Hotnuts · « **Reply #15 on:** July 23, 2010, 12:12:31 AM »

Heres a few shots of my home porting job.
Made 440+ WHP and got my car to 214mph in 3 miles.

Heres what ya do:

Get a head that has been ported by someone else, the head can be good or bad. I have a head on my 1507 that I used ported by Terry Vance. Did not need to pull the reference head off the motor.
Get a snap gauge.
Using the snap gauge measure the port at different stages of depths.
Using a die grinder with carbide rasp (I use flame tip) make the ports on the new head exactly like reference head. Dont go deeper and match the port profile.

The key is using a pre ported head.
If I had needed a ported head I have some friends that would of let me borrow one or given me one that was destroyed beyond repair.

Once you port your own head and polish it you will find the money you would spend to have the job done will be money well spent.
BUT....

It can be done.

~JH

Yngve · « **Reply #16 on:** July 23, 2010, 12:43:15 AM »

Quote from: Jonny Hotnuts on July 23, 2010, 12:12:31 AM

Heres a few shots of my home porting job.
Made 440+ WHP and got my car to 214mph in 3 miles.

Heres what ya do:

Get a head that has been ported by someone else, the head can be good or bad. I have a head on my 1507 that I used ported by Terry Vance. Did not need to pull the reference head off the motor.
Get a snap gauge.
Using the snap gauge measure the port at different stages of depths.
Using a die grinder with carbide rasp (I use flame tip) make the ports on the new head exactly like reference head. Dont go deeper and match the port profile.

The key is using a pre ported head.
If I had needed a ported head I have some friends that would of let me borrow one or given me one that was destroyed beyond repair.

Once you port your own head and polish it you will find the money you would spend to have the job done will be money well spent.
BUT....

It can be done.

~JH

Didnt know that Terry Vance ported heads...

Byron Hines on the other hand.......

midnight black man · « **Reply #17 on:** July 23, 2010, 07:09:45 AM »

a clients exhaust...hand porting...

slatroni · « **Reply #18 on:** July 23, 2010, 10:25:59 AM »

Thanks for the pics midnight black man and Jonny Hotnuts! I cant wait till my head comes in!

gsx1300r_is4me · « **Reply #19 on:** July 25, 2010, 10:19:23 AM »

Quote from: midnight black man on July 23, 2010, 07:09:45 AM

a clients exhaust...hand porting...

Now that's nice!!!

slatroni · « **Reply #20 on:** July 25, 2010, 05:40:04 PM »

That looks good!

mike46 · « **Reply #21 on:** July 31, 2010, 09:10:39 PM »

Quote from: midnight black man on July 23, 2010, 07:09:45 AM

a clients exhaust...hand porting...

Crossbuffs

midnight black man · « **Reply #22 on:** August 01, 2010, 04:19:24 AM »

Quote from: mike46 on July 31, 2010, 09:10:39 PM

Quote from: midnight black man on July 23, 2010, 07:09:45 AM
a clients exhaust...hand porting...

Crossbuffs

no...

slatroni · « **Reply #23 on:** August 01, 2010, 09:15:04 AM »

My electric die grinder and porting kit is on its way! What kind of HP can I expect from a " clean-up and polish" port job? I am going to send out some cams for a .368 regrind also.

Jonny Hotnuts · « **Reply #24 on:** August 01, 2010, 11:22:37 PM »

Quote

My electric die grinder and porting kit is on its way! What kind of HP can I expect from a " clean-up and polish" port job? I am going to send out some cams for a .368 regrind also.

I suspect you will loose 2-3HP.

~JH

slatroni · « **Reply #25 on:** August 02, 2010, 01:28:09 AM »

huuu?

Jonny Hotnuts · « **Reply #26 on:** August 02, 2010, 10:37:01 AM »

Changing the profile of the port, enlarging and removing physical obstructions (as caused by valve guides protruding into the port, and misaligned valve seats, ect. ) is where the HP is made. Much of the profile changes that improve HP are a closely guarded secret between head porters and is why one head makes more HP then another.

A nice shiny port flows worse then a slightly rough one. This is due to the boundary layer formed along the walls of the port and a rough (*within reason) keeps the boundary layer from being 'lazy' and results in better flow.

A nice shiny port sells port jobs but doesnt help performance.

-also....

A proper valve job and the angles used on the seat can make a significant difference in HP. True a better flowing profile on the seat wont last 100K miles but will make more HP.

http://www.motorcycleproject.com/motorcycle/text/cows-porting.html

Good lucki

~JH

magus · « **Reply #27 on:** August 02, 2010, 12:19:13 PM »

I had heard it is best to leave the intake side a bit ruff for better fuel air mixture. I know the kws head on the gixxer I had was ruff on both ends.

so is the school of thought that a basic clean up job is pretty worthless? with or with out polishing after?

slatroni · « **Reply #28 on:** August 02, 2010, 03:07:22 PM »

I am planning on doing a "scotch bright" finish on the intake side and a polish on the exhaust. I am not and expert on this, but it would seem to me it would be better than stock. Please give me your feedback.
Thanks

tyboogie · « **Reply #29 on:** August 02, 2010, 03:27:57 PM »

Quote from: Jonny Hotnuts on August 02, 2010, 10:37:01 AM

Changing the profile of the port, enlarging and removing physical obstructions (as caused by valve guides protruding into the port, and misaligned valve seats, ect. ) is where the HP is made. Much of the profile changes that improve HP are a closely guarded secret between head porters and is why one head makes more HP then another.

A nice shiny port flows worse then a slightly rough one. This is due to the boundary layer formed along the walls of the port and a rough (*within reason) keeps the boundary layer from being 'lazy' and results in better flow.

A nice shiny port sells port jobs but doesnt help performance.

-also....

A proper valve job and the angles used on the seat can make a significant difference in HP. True a better flowing profile on the seat wont last 100K miles but will make more HP.

http://www.motorcycleproject.com/motorcycle/text/cows-porting.html

Good lucki

~JH

I heard it is best to have a "turbulant" airflow that is what happens when you leave the intake side rough.

slatroni · « **Reply #30 on:** August 02, 2010, 03:50:56 PM »

Quote

I heard it is best to have a "turbulant" airflow that is what happens when you leave the intake side rough.

This makes sense when you think about it. I don't want the air/fuel sticking to the walls of the intake port. But rough, how rough? is a scotch bright finish rough enough, or should I leave the 120grit finish? In the old days we would polish the exhaust side, but the exhaust is still on the wet side. So would the effect be the same on the exhaust side?

tyboogie · « **Reply #31 on:** August 02, 2010, 05:21:53 PM »

Quote from: slatroni on August 02, 2010, 03:50:56 PM

Quote
I heard it is best to have a "turbulant" airflow that is what happens when you leave the intake side rough.

This makes sense when you think about it. I don't want the air/fuel sticking to the walls of the intake port. But rough, how rough? is a scotch bright finish rough enough, or should I leave the 120grit finish? In the old days we would polish the exhaust side, but the exhaust is still on the wet side. So would the effect be the same on the exhaust side?

Hell if I know that's just what I've heard

slatroni · « **Reply #32 on:** August 02, 2010, 06:30:35 PM »

HA! I am in the same boat! I learn everything the hard way, but I learn good!

Jonny Hotnuts · « **Reply #33 on:** August 02, 2010, 07:53:13 PM »

Also welding up your PAIR valve ports help HP. I have never seen any data on this but its a good sized hole in the top of the exhaust port and will hurt exhaust velocity.

Also look at the way I profiled my valve seats to flow with the port on my first posted pic and this (*the other side)

(Before on left, after profiling on R)

You may be able to use these pics to help grind some excess material off your ports. Just make damn sure they are all the same.

Here is a really nasty transition between the OEM valve seat and the port. Its hard to tell how bad it is from the pic but its almost 2.25mm deep. This can all be blended out.

As far as doing your own port job I still say get a ported head from good head porter and copy the profile on your head.
It really is not hard and takes the worry out of going too far and you KNOW you will be making HP.

I will say that I didnt find anywhere on my example head that wasnt enlarged at least 1mm on all surfaces in the port over OEM. (So mesuring from side to side would be 2mm larger diameter).

~JH

slatroni · « **Reply #34 on:** August 02, 2010, 08:13:42 PM »

Thanks again Jonny! I figured I would do just that with the seats. Is that your finished porting job? That has more texture than I had planned to leave. I wish I could get my hands on a ported head to see where they ground out. I have seen lots of HD heads but no Busa heads. One of my friends builds HiPower Harley motors and he wants to look at my head. He is on his way over now.

dave393 · « **Reply #35 on:** September 09, 2010, 12:11:13 PM »

80 grit is the smoothest you should go. Anymore and you lose low end power. I have ported hundreds of Harley heads over 30 years. Low speed tuning is more difficult.

piratediverjefff · « **Reply #36 on:** September 09, 2010, 07:56:04 PM »

Quote from: tyboogie on August 02, 2010, 05:21:53 PM

Quote from: slatroni on August 02, 2010, 03:50:56 PM
Quote
I heard it is best to have a "turbulant" airflow that is what happens when you leave the intake side rough.

This makes sense when you think about it. I don't want the air/fuel sticking to the walls of the intake port. But rough, how rough? is a scotch bright finish rough enough, or should I leave the 120grit finish? In the old days we would polish the exhaust side, but the exhaust is still on the wet side. So would the effect be the same on the exhaust side?
Hell if I know that's just what I've heard

Nosgsx1300 · « **Reply #37 on:** September 11, 2010, 03:52:46 PM »

someone should buy my HMP Ported head and copy it

Chet · « **Reply #38 on:** September 12, 2010, 11:10:33 AM »

Quote from: Jonny Hotnuts on August 01, 2010, 11:22:37 PM

Quote
My electric die grinder and porting kit is on its way! What kind of HP can I expect from a " clean-up and polish" port job? I am going to send out some cams for a .368 regrind also.

I suspect you will loose 2-3HP.

~JH

Unfortunately what "looks good" to the human eye may not work well at all.
Strongly suggest you perform only very minor changes unless you have a proven design to work from.

Chet

ras31 · « **Reply #39 on:** December 15, 2010, 10:10:12 AM »

Quote from: Chet on September 12, 2010, 11:10:33 AM

Quote from: Jonny Hotnuts on August 01, 2010, 11:22:37 PM
Quote
My electric die grinder and porting kit is on its way! What kind of HP can I expect from a " clean-up and polish" port job? I am going to send out some cams for a .368 regrind also.

I suspect you will loose 2-3HP.

~JH

Unfortunately what "looks good" to the human eye may not work well at all.
Strongly suggest you perform only very minor changes unless you have a proven design to work from.

Chet

I agree with that

slatroni · « **Reply #40 on:** December 15, 2010, 09:14:32 PM »

Thanks again for all the imput! I have finished the porting and bench shimmed the valves. I will be putting the head on in the next week or two along with cams and a 40 shot and s2000 injectors. I will give you the #'s after the dyno pull. I am going to tune with my wego.
Thanks again
Steve

Competition CNC · « **Reply #41 on:** December 22, 2010, 07:58:31 AM »

The most important areas are the ports minimum cross sectional area, the short turn radius the valve seat profile and seat choke %. These are all determined by the size of the engine and at what rpm you want peak hp at. Intake cam duration is also a factor on determining the ports MCSA.

Any visual surface treatments on a fuel injected modern high velocity port is purely aesthetic and have very little effect on flow or performance.

It is true that carburetor street engines will like a rougher port wall to help keep the a/f mixture in suspension. with injectors its not so important.

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Author Topic: DYI Head Porting (Read 19258 times) Tweet