Question on Heads???

[Don D]

why replace stock low mileage guides

Simple the factory threw us a little screwball and now all the newer heads have ~.0017 intake and ~.0025 exhaust clearance. Valves can be felt and do wobble now, new stock heads are like this. They didn't with the older heads. Why do this? Warrenty simple as that. They will make it past the 2 yr mark before the seals are shot and not seize the rear exhaust valves in the guides. Ethanol fuel, added heat, and the low cost cast iron guide material are the root causes of the need for added clearance. We, the service industry, change them with higher quality guides that are bronze manganese tapered so they flow better, set up safely with less clearance, and last far in excess of 50K miles assuming regular oil changes and no air filter issues. Valve seals are premium viton and last far longer. This lower oil quantity coming down the guides keeps those valves carbon free so they flow the same as they did when installed for a much longer time and mileage period, more power longer.. 

Have them install the 1.9's? hardly worth it IMHO

Hardly worth using the stockers IMHO, more work less flow. To get a decent profile on the seats, concentric (not done with Neway cutters) and grinding the stock valve you end up with the valves sunk and that hinders flow. The stock 2006up intake port has a bowl that measures ~1.920 which without any grinding is sized perfectly for the 1.9 valve, as is the intake opening diameter perfect size, after the seat throat is opened proportionally, a good seat is machined, and the floor and the rest of the port are mildly blended air speed increases at all lifts as well as flow. The 1.9 is a natural fit for the twin cam but has some production cost issues that precludes their use IMO. The sportster valve head size fits a high shareholder model and parts commonality.

This work is very beneficial for all cams being used in terms of performance, quiet operation, and added reliability / durabiltiy. It does however take time and parts so the cost goes up very slightly over the low cost leaders.

[wfolarry]

I've heard of hardened seats but who has hardened valve faces? I know they changed material but what kind of hardening process are they using? How deep does it go? What's the safe amount of material that can be removed?
Speaking of valve seats HD uses different material on their stock heads vs the SE heads. Which valves should I be using in each?
Should I put my valve grinder on e-bay now?
All these new valves do you check to see if they were ground within spec?
I paid extra money for a chuck on my valve grinder that has .0002 or less runout. I check every new valve I get.
The only ones tossing the valves are the ones that don't have a valve grinder that can do the job right. Or don't have a valve grinder at all. That's for faces & stems.


As far as valve sizing goes I don't have any problem getting those little 1.8 intakes flowing just fine. Those stock ex. valves work fine too. I'm not against bigger valves but I don't think they are mandatory.

The loose guide fit is oil based. Cars, bikes everything. Big trucks will be next. Caterpillar stopped making engines for highway use because of the EPA.

There is a way to sink valves & improve flow.


I am a little dated as well. Rebuilt my first smallblock chevy in autoshop in 1972. Started doin' HD's a couple years later. I guess it's time for me to retire. I must be fallin' behind the times. Just be an assembler with all new parts. Forget all this machining crap. What was I thinking?

The times they are a changin' [Still holds true today]

[Deye76]

"There is a way to sink valves & improve flow."

The guy I know who builds motors for the Hemi challenge, and runs a car in it also thinks/knows so. He does it to the few H-D heads he's coerced into porting.

Don't retire Larry, the midwest is almost "head porter" bankrupt now.

[Don D]

I agree with you Larry
I know how to do that too, more work sinking the valves and working the chamber for a pressure recovery deal. Bottom line is it takes time and time is money. Most of us know how to take things that are less than our ideal choice and make it work if we have to. We also have a lot of opinions on what the "ideal" is.
Look at the car head porters, the restricted classes, and stock castings etc.
But the bottom line is always there is no free lunch and the bargain low price leaders just don't spend the time or offer any improvement in parts, can't do it, not in the budget. Plus the valve grinding techniques and seats etc are in many cases not as high quality as OEM. We are trying to improve things, and many do, but that takes machines, tooling, time and parts. All things that we need to be paid for. This is not a gouge mind you just a reasonable service offering for a decent return.

[Admiral Akbar]

I've heard of hardened seats but who has hardened valve faces? I know they changed material but what kind of hardening process are they using? How deep does it go? What's the safe amount of material that can be removed?
Speaking of valve seats HD uses different material on their stock heads vs the SE heads. Which valves should I be using in each?
Should I put my valve grinder on e-bay now?
All these new valves do you check to see if they were ground within spec?
I paid extra money for a chuck on my valve grinder that has .0002 or less runout. I check every new valve I get.
The only ones tossing the valves are the ones that don't have a valve grinder that can do the job right. Or don't have a valve grinder at all. That's for faces & stems.

Yep,

Not sure, it may only be heat treat..  Ask your valve reps and see what they say..

I suspect that if you grind of 0.040 you've gone too far..

Don't know

Don't put the grinder on ebay send it to me.. 

Sorta,

cool..

I don't have a valve grinder.. Had one but figured I'd never use it again so sold it.. Needed money at the time.. Right now it's still cheaper to replace.

Max

[Don D]

I have checked new valves and from AV&V they are very close to perfect. I do not grind them after checking. I have an accu-chuck collet system and my machine holds very true tolerances.

[autoworker]

Good post Larry.

[ultra 08]

I,m with Steve I didn,t spend alot of money to get 90 hp and 100 ft. lbs. out of my 96" and the heads haven,t even been off. My power is on at 2145 rpms with 90 ft. lbs It really makes for a nice ride, most people ride in the low to mid range of the rpm band.

[strokerjlk]

Good post Larry.

+2

[Admiral Akbar]

Yeah good post Larry,

I wacked on a early TC  exhaust valve and it don't look hardened.. While the steel is tough, it don't appear to be hard faced or treated. Could be but I wouldn't be surprised if it ain't but just work hardened a little.  Early in the 70s Honda came out with a service bulletin that said to any valve that looked  like it needed refacing because the grinder could remove the hard face on the valves and they would not last... Have seen it on a number of builds (hondas).  I assumed this carried over when everything went unleaded as the hard face and hard seats kept those motor running and others were having problems.. Still I wouldn't be surprised if some of the higher end valves have hardened faces..

Do you want my address to send the valve grinder too?   

Max

[Hillside Motorcycle]

I've heard of hardened seats but who has hardened valve faces? I know they changed material but what kind of hardening process are they using? How deep does it go? What's the safe amount of material that can be removed?
Speaking of valve seats HD uses different material on their stock heads vs the SE heads. Which valves should I be using in each?
Should I put my valve grinder on e-bay now?
All these new valves do you check to see if they were ground within spec?
I paid extra money for a chuck on my valve grinder that has .0002 or less runout. I check every new valve I get.
The only ones tossing the valves are the ones that don't have a valve grinder that can do the job right. Or don't have a valve grinder at all. That's for faces & stems.


As far as valve sizing goes I don't have any problem getting those little 1.8 intakes flowing just fine. Those stock ex. valves work fine too. I'm not against bigger valves but I don't think they are mandatory.

The loose guide fit is oil based. Cars, bikes everything. Big trucks will be next. Caterpillar stopped making engines for highway use because of the EPA.

There is a way to sink valves & improve flow.


I am a little dated as well. Rebuilt my first smallblock chevy in autoshop in 1972. Started doin' HD's a couple years later. I guess it's time for me to retire. I must be fallin' behind the times. Just be an assembler with all new parts. Forget all this machining crap. What was I thinking?

The times they are a changin' [Still holds true today]

 
Scott

[BVHOG]

I've heard of hardened seats but who has hardened valve faces? I know they changed material but what kind of hardening process are they using? How deep does it go? What's the safe amount of material that can be removed?
Speaking of valve seats HD uses different material on their stock heads vs the SE heads. Which valves should I be using in each?
Should I put my valve grinder on e-bay now?
All these new valves do you check to see if they were ground within spec?
I paid extra money for a chuck on my valve grinder that has .0002 or less runout. I check every new valve I get.
The only ones tossing the valves are the ones that don't have a valve grinder that can do the job right. Or don't have a valve grinder at all. That's for faces & stems.


As far as valve sizing goes I don't have any problem getting those little 1.8 intakes flowing just fine. Those stock ex. valves work fine too. I'm not against bigger valves but I don't think they are mandatory.

The loose guide fit is oil based. Cars, bikes everything. Big trucks will be next. Caterpillar stopped making engines for highway use because of the EPA.

There is a way to sink valves & improve flow.


I am a little dated as well. Rebuilt my first smallblock chevy in autoshop in 1972. Started doin' HD's a couple years later. I guess it's time for me to retire. I must be fallin' behind the times. Just be an assembler with all new parts. Forget all this machining crap. What was I thinking?

The times they are a changin' [Still holds true today]

Awesome post!!!!!

[Don D]

Nice work, I am sure, knowing you as I do, regardless of the appearance the result is right on.
And of course we all grind valves.
I just was testing a new 110 head and swapped exhaust valves (stock to another new premium stainless valve) with no other changes picked up 19cfm peak and gains from .100 up.

[Admiral Akbar]

I just was testing a new 110 head and swapped exhaust valves (stock to another new premium stainless valve) with no other changes picked up 19cfm peak and gains from .100 up.

Isn't it neat when you find this.. Max.

[wfolarry]

Put them in the motor & let me know how much more power it makes.

Reminds me of another guy who said he ports the head then tries different valves to see which one flows best & that one goes in there. If he was a REAL porter he would know how to shape the port for the type of valve he was using. Works good if you're racing flowbenches though.

[Admiral Akbar]

Seems to me that since there isn't an easy way to put metal back into the port, that making a port bigger to accommodate a different valve might not be a good idea.. I guess it could be the results of velocity becoming too high, and material needing removal, but it may be just the due to changing the flow around the seat and taking metal out there may or may no be a good thing..

Max
(not a head porter)