Milwaukee Eight Cylinder Heads

[ocezam]

The REAL question is: can they be retrofitted to my TwinCam??

Nope

[rigidthumper]

I used one of those for almost 20 years. 

[HD/Wrench]

Quick tranny observation, not only do people not downshift going up grades, they don't downshift going down. Had a minivan driver complaining about using so much brake coming down a mountain grade. I asked if he downshifted out of overdrive, and maybe even to second gear. He looked at me like I was talking a different language.

I thought you gave up trying to fix stupid?
Ron

I have shirt like that.. " I cant fix stupid but I can diagnose it "   

[dynajohn]

I'm bettin John Sachs has some ideas[emoji6]

4 valve heads are nothing new, Honda (and others) have been using them for quite a while.
One of the differences is 'swirl', has become 'tumble'.

There are countless advantages to 4 valve over 2. More flow with less lift being a biggie. Lighter
components, better cylinder fill, ports are smaller (higher velocity) and on and on...

This will be a game-changer. Hopefully the motors will be able to hold up to these things...

Well said. look to shops that have a ton of 4 valve experience and are also porting Harley heads like Ward Performance and Star racing to be first out of the blocks in developing good ported 4 valve Harley heads. Both of these shops have tons of pro stock experience with 4 valve heads. Bigger alone is almost never better particularly for street ported heads, 2 valve or 4 valve.

[tmwmoose]

The heads are not retro to any other engine
There are adjustable push rods and cam available with big bore kit also

Boy I wish Harley started using those exhaust studs years ago to many times when your in a hurry ya got one that just fights ya all day to get started

[TorQuePimp]

Think New way when it comes to valve tools
Just my 2 cents
Spendy but long lasting

Neways should never be used on a Harley....lawnmower...at best

[rbabos]

Think New way when it comes to valve tools
Just my 2 cents
Spendy but long lasting

Neways should never be used on a Harley....lawnmower...at best

Way to go, as in hurt the guys feelings. Anyway, I've seen them and wondered about them. Care to share the downside of these cutters so the rest of us can make a determination?
Ron

[SP33DY]

Way to go, as in hurt the guys feelings. Anyway, I've seen them and wondered about them. Care to share the downside of these cutters so the rest of us can make a determination?
Ron

I started using Neway cutters in the '70's, and then progressed to grinders and guide and seat machines.

They are as good as the person using them.

For freshening a seat when the original valve guide is being retained, they work fine.

Solid pilots work best with these, in my experience the expanding pilots are not as good.

Taking your time and working carefully, you can do a good job.

Paint the seat with Dykem, then gently turn the 46° cutter once around on the seat and check to make sure that it cleaned off some Dykem all the way around. If not, try to reseat the pilot or you will have concentricity problems, poor valve seal etc. (Lack of concentricity can lead to a broken valve).

Once the 45° is clear of pitting, put prussian blue on the seat and see where it transfers to the valve. That way you can make the necessary top and bottom cuts to place the seat contact in the correct place on the valve.

When you're done check your valve to seat contact with a light application of prussian blue. It should transfer an unbroken ring to the seat, then clean off the valve, it should transfer an unbroken ring to the valve.

The first down side is it's a slow process compared to using a seat grinder or a guide and seat machine.

The second downer is that it's a lot harder to do if you replaced the valve guide. You would think it doesn't matter, especially with a high quality guide like an AV&V or HQ, that has almost perfect concentricity from i.d. to o.d. out of the box. But usually the relationship of the valve guide to the seat changes a little bit after removing the old guide and installing the new one.

At this point properly refinishing the seat with Neway cutters is a real chore. It can be done, but it requires a certain amount of skill, patience and feel.

If you just want to do your own heads and maybe help a buddy once in a while, it is a good way to do it. You may get the bug, then top quality valve grinders, and guide and seat machines, are in your future.

[Pete_Vit]

Quick tranny observation, not only do people not downshift going up grades, they don't downshift going down. Had a minivan driver complaining about using so much brake coming down a mountain grade. I asked if he downshifted out of overdrive, and maybe even to second gear. He looked at me like I was talking a different language.

That minivan likely had disc brakes on the front and drums on the back or maybe all disc.  Had he (drums all around) or a heavier van/truck,  he would learn to use the transmission lower gears in a pretty quick time.

Once you experience genuine brake "fade",  you don't soon forget.

[rbabos]

Way to go, as in hurt the guys feelings. Anyway, I've seen them and wondered about them. Care to share the downside of these cutters so the rest of us can make a determination?
Ron

I started using Neway cutters in the '70's, and then progressed to grinders and guide and seat machines.

They are as good as the person using them.

For freshening a seat when the original valve guide is being retained, they work fine.

Solid pilots work best with these, in my experience the expanding pilots are not as good.

Taking your time and working carefully, you can do a good job.

Paint the seat with Dykem, then gently turn the 46° cutter once around on the seat and check to make sure that it cleaned off some Dykem all the way around. If not, try to reseat the pilot or you will have concentricity problems, poor valve seal etc. (Lack of concentricity can lead to a broken valve).

Once the 45° is clear of pitting, put prussian blue on the seat and see where it transfers to the valve. That way you can make the necessary top and bottom cuts to place the seat contact in the correct place on the valve.

When you're done check your valve to seat contact with a light application of prussian blue. It should transfer an unbroken ring to the seat, then clean off the valve, it should transfer an unbroken ring to the valve.

The first down side is it's a slow process compared to using a seat grinder or a guide and seat machine.

The second downer is that it's a lot harder to do if you replaced the valve guide. You would think it doesn't matter, especially with a high quality guide like an AV&V or HQ, that has almost perfect concentricity from i.d. to o.d. out of the box. But usually the relationship of the valve guide to the seat changes a little bit after removing the old guide and installing the new one.

At this point properly refinishing the seat with Neway cutters is a real chore. It can be done, but it requires a certain amount of skill, patience and feel.

If you just want to do your own heads and maybe help a buddy once in a while, it is a good way to do it. You may get the bug, then top quality valve grinders, and guide and seat machines, are in your future.

Good explanation but isn't grinding have the same issue with guide and or replacements? I guess the grinder would be quicker and less prone to off center seat loading?
Ron

[TorQuePimp]

Think New way when it comes to valve tools
Just my 2 cents
Spendy but long lasting

Neways should never be used on a Harley....lawnmower...at best

Way to go, as in hurt the guys feelings. Anyway, I've seen them and wondered about them. Care to share the downside of these cutters so the rest of us can make a determination?
Ron

Concentricity

All seat and guide work.....race street or otherwise should get the same level of attention

  the pilots are too short and do not center properly

Relying on a person to use the T handle or the gimmic powered driver they sell or a damn hand drill to cut seats that will be even mediocre is a stretch

Ive had "performance" heads in my shop done recently done with neways and if you want worn out guides....you got your moneys worth

Are some people better at it than others ? yes ofcourse

I own about $3500+ worth of Neway products and use modified drivers in my seat and guide machine for applications out of the realm of normal machine operation.

http://new3acut.com/new3acut.html

makes some tooling

I get the rest from the company in India who makes all of my carbide pilots

[SP33DY]

Good explanation but isn't grinding have the same issue with guide and or replacements? I guess the grinder would be quicker and less prone to off center seat loading?
Ron

The grinders and guide and seat machines are still prone to the same problems as the Neway cutters, but it's not as hard for a conscientious machinist to get it right. Not all seat grinders and guide and seat machines are created equal either. Over the last 45 years I've been over that ground. I have owned or operated most types of seat grinders, and guide and seat machines. My current machine is a Serdi that I bought new, and even it has it's quirks.

Until you have checked valve seats with a good concentricity gauge on a carbide pilot, and checked valve face concentricity in a good fixture, it's hard to realize how bad a valve job can be, even though it may look nice and pass the Prussian blue check.

It's all in the details, regardless of how you try to get there.

[aharp]

The second downer is that it's a lot harder to do if you replaced the valve guide. You would think it doesn't matter, especially with a high quality guide like an AV&V or HQ, that has almost perfect concentricity from i.d. to o.d. out of the box. But usually the relationship of the valve guide to the seat changes a little bit after removing the old guide and installing the new one.

The amount of cutting required when replacing with an AV&V guide has made me greatly question the MOCO's order of operations and/or concentricity of the oem valve guides.

[SP33DY]

The amount of cutting required when replacing with an AV&V guide has made me greatly question the MOCO's order of operations and/or concentricity of the oem valve guides.

The current guides from the mother ship have been checking good on a guide concentricity gauge. I have been finding the seat concentricity on new or unmolested take-off twin cam heads to be all over the map. Some are spot on, and some are way out of concentricity. I have not had a M8 in here to check yet.

I pay a lot of attention to this and check record almost everything from the start to finish of each job. Even on heads that had good seat concentricity to start with, they usually lose some alignment when changing the guides. I have gone to the trouble to make piloted fixtures to remove and replace guides, and I heat the heads, and chill the guides for both removal and replacement, but they still usually show some misalignment when the new guides are in.

I think it is just the nature of the head castings, and how they react to the press fit of the guides.

[Don D]

Until you have checked valve seats with a good concentricity gauge on a carbide pilot, and checked valve face concentricity in a good fixture, it's hard to realize how bad a valve job can be, even though it may look nice and pass the Prussian blue check.

True that 

I pay a lot of attention to this and check record almost everything from the start to finish of each job. Even on heads that had good seat concentricity to start with, they usually lose some alignment when changing the guides. I have gone to the trouble to make piloted fixtures to remove and replace guides, and I heat the heads, and chill the guides for both removal and replacement, but they still usually show some misalignment when the new guides are in.

Of course they do. Check the guides that came out for concentricity to the OD. Tells most of the story. The rest of the story is the MOCO does valve jobs by CNC using a tool that sets from a datum and plunges the guide hole and seat with a form tool all at once. Lean manufacturing at it's finest. When we replace the guides that are perfectly concentric and in alignment with what should be the datum, the spring seat with a perpendicular guide hole, now the seat ring may or may not be close. Add annoyances such as chambers that are lower or higher due to core shift and you have more nuances. IME early twin cams and EVOs did no have this issue. We have to play the hand dealt or fold and replace and remachine everything.

[sbcharlie]

Got to love those cookie cutter valve jobs

[jsachs1]

Got to love those cookie cutter valve jobs
[/quote)
Especially the MoCo big valve heads with the large throats. The seat id is lucky to have a 360* third angle. Their location relative to the guide, is the reason for the proud 45*. 
John

[Don D]

I am not sure I understand how they machine the big valve heads in production. Those seats have an undercut that would not be possible with a form tool that plunges. Perhaps it tool changes after plunging the guide hole and goes to a single point tool and forms the seat like a Newen does but without a pilot which is not needed. I sure hate the material they use in those seats

[TorQuePimp]

I am not sure I understand how they machine the big valve heads in production. Those seats have an undercut that would not be possible with a form tool that plunges. Perhaps it tool changes after plunging the guide hole and goes to a single point tool and forms the seat like a Newen does but without a pilot which is not needed. I sure hate the material they use in those seats

That's where the guys with a Serdi or newen or peg have an advantage.....cutting speed and a spritz of lube.....nice shiny finish on those powdered metal bastard's

[1FSTRK]

Has anyone confirmed that factory seats are re-cut after installation in the head?

With modern manufacturing techniques where the guide bore and seat bore are cut in the same set-up and the the guides and seats are precision machined before installation do they then ream the guide and re-cut the seat at all?

[Don D]

http://www.guehring.de/pdf/Cylinder_head_machining.pdf

[prodrag1320]

I used neway cutters before we got our SERDI 100.their OK for a guy working on his own (& buddies) heads.when used with carbide pilots (& a lot of patience),they will do a OK job,but nothing compaired to a real guide & seat machine.we`ve done tons of 4 valve stuff here for years,with the HD 4 valve stuff & jap heads (been doing a lot of yamaha stratoliner heads for a couple shops up north for the past couple years)

[leafman60]

Was there not a 4 valve head awhile back that fitted to a EVO? Fueling,Quantum,Rivera I think. What happened to those and could the ideas from the M-8 be used/based on those? I have been told of Evos with TC top end, so why not TC Hemi heads? Same design on the rockers but maybe not Euro 4/Ca legal. WHO would care? Are not the 4 valve design best at rpms better then 5500? What would a EVO/Hemi 4 motor do to the M-8 114 side by side??? V-Rod ver stock M-8 114 

Feuling

-but they never made a big splash. The slow-spinning H-D twins seemed to benefit less from 4 valves than did other engines more typically revved to higher levels.

http://thekneeslider.com/4-valve-hemi-heads-for-harley-big-twin-engines/

http://www.feulingparts.com/aboutus.php

[rbabos]

Was there not a 4 valve head awhile back that fitted to a EVO? Fueling,Quantum,Rivera I think. What happened to those and could the ideas from the M-8 be used/based on those? I have been told of Evos with TC top end, so why not TC Hemi heads? Same design on the rockers but maybe not Euro 4/Ca legal. WHO would care? Are not the 4 valve design best at rpms better then 5500? What would a EVO/Hemi 4 motor do to the M-8 114 side by side??? V-Rod ver stock M-8 114 

Feuling

-but they never made a big splash. The slow-spinning H-D twins seemed to benefit less from 4 valves than did other engines more typically revved to higher levels.

http://thekneeslider.com/4-valve-hemi-heads-for-harley-big-twin-engines/

http://www.feulingparts.com/aboutus.php

Think EPA more then performance although the extra performance aspect is there as a side benefit.
Ron

[Eccool]

No one has had a set of these heads on the flow bench yet?