Harley heads-,CC ,Porting, ceramic ETC

[afterburn 549]

Been through a lot of mistakes with this, hope I got it right this round.
Last year I never got it together at all.
Just measured this one head and it EXACTLY 83 CC !! (purrrfect)
For those of you that have never ever operated a Buret CC-ing a head, it is a PIA!
One wrong move, and start all over.
This was the final and last step almost.
What is left- measure gap and set tensions on piston rings.
Last time they were set to 12 lbs drag.
Going for 10 lbs drag this time
The grey color on valves and heads is ceramic. (Swains)
These are raised ports, 50 deg seats rather then 45
Here is hoping for 1.30 per cube at a usable RPM.
That is the goal.

[asphaltgambler]

Looks great ! good work! I would suggest lessdeck height. I've done .020" - sometimes a little less depending on bore size, piston fit. If you're running aluminum jugs, they will ' grow' slightly when up to temp. So you can run tighter squish. That's where the power is in efficient combustion.

[Brando]

Dang those are looking good afterburn. Please share more pictures as you assemble it all!

[afterburn 549]

Fitting the rings, not a job for the impatient!
If they are NOT set Sq to the bore the measurement for the required gap will be so wrong.
They sell tools to quickly jig the ring at a prescribed depth.
For this one job, I improvised.
I scribed a line around a beer glass that fit almost exact to the bore,
Seems apropos for Knarly Harley. LOL
This is no place for a flat file or some other rude crude backyard method of machining off some material.
Invest in a ring grinder of some sorts.
In the end, you will know you have done it correctly if you butt the ends together and you can hardly see the ends.
Next, you will want to dress the machined end with a fine stone to remove all burrs and always "dress" going to the inside so as not to chip the face of the ring on the outside edge

[DaveE]

Originally Posted by Brando

Dang those are looking good afterburn. Please share more pictures as you assemble it all!

Seconded!

[Yorkie]

As an ex-XL1000 Iron Head owner this is really cool to see old school motor building techniques. Looking forward to seeing the ring drag tests as I've never heard of that before - probably because I'm a total shade tree mechanic. Thanks for sharing.

[Bill Douglas]

And THEN.

After it's back together, then it's the breakin procedure.

[Jeff Higgins]

Beautiful stuff. Too bad it's all going to be out of sight, inside the motor.

So, you know me - I'm about as hard-core Harley as anyone around here. So, I'm not trying to bust your balls here or anything, but I just have to ask - what is the real-world benefit of all of this? It just strikes me as a good deal of effort and expense for very little real-world gain. I have to wonder - if another motor were built, will all of the same components, but without the coatings, meticulous cc'ing of the combustion chambers, ring drag checks, and all of that - how much difference would there really be? Enough to even tell the difference from the saddle? How much would just be "placebo affect", convincing yourself it must be better because of all of the attention to detail?

[Bill Douglas]

Originally Posted by afterburn 549

The last few I have used the "eliminate the Ring micro welding technique"

I had to google that. It would be a major PITA for that to happen.

A racing buddy of mine used to say if an engine doesn't get put under load and the rings broken in/matched to the bore in the first 20 minutes, the engine will never be any good. He said they glaze and never fit each other as well as they could, resulting in lost power and excessive oil consumption.

Sorry, didn't mean to introduce a new subject.

[Jeff Higgins]

Engine break-in... I well remember my big block MOPAR drag racing days. There was always a contradiction. When running flat tappet, or the old "mushroom" tappet cams, the cam grinders admonished us to run the thing at no less than about 3,000 rpm for at least half an hour to "burnish" the cam lobes and lifter faces to avoid wearing through the hardening and pitting them. What a great way to similarly polish cylinder bores and ring faces to ensure they would never seal...

When we started running roller tappet cams that whole cam and lifter break-in thing went away. With no practical way to run the car hard until it was at the track, our motto was "we seat the rings on the first burnout". Sounds harsh, but it never failed.

Oh, and afterburn, I absolutely get your drift. I've never been one to take the easy, accepted path either. How you do it is as important as that you do it. My current 3.0 liter MFI motor is exactly that kind of approach. There are far easier ways to get there from here. Not interested.

[Jeff Higgins]

Albert Blue. Same one for 20 years. Three iterations of the motor, just for fun.

[asphaltgambler]

^^^^ All true and very well explained^^^^^. With today's technology in metallurgy, piston fit and ring control can free up frictional HP that is lost on every engine. I was told many years ago by an very experienced engine builder that a hot street / mild strip BBC 454 engine consumed at least 100 HP at 6K RPM's in frictional loss with a flat tappet cam. This was in the early 1980's.

1 trick that I would do on HD's is install a smaller crank (primary drive to transmission) sprocket to slow the trans speed down which does 2 things: Reduces overall driveline drag and makes shifting at high engine RPM's easier for the dog/ teeth to engage.

In the end it is true hot rodding taking every possible advantage from the gas cap to the rear tire(s)

[asphaltgambler]

^^^^^^ Yes, what a lot of people forget is what happens after the crank hub to the drive tire.2 identical bikes with same HP/ TQ - 1 with less rotating / spinning mass ( after flywheel ) will accelerate quicker than the other with nothing improved / reduced.

Again, hot rodding 101

[Jeff Higgins]

My very best riding buddy's older brother (the guy who ruined my life forever by introducing me to this hot rod Harley nonsense ) was (is) a pretty renowned local builder of hot rod Pans, Shovels, and Ironheads. He built a stroker shovel back in the early '80's on which he knife-edged the flywheels, ran a belt primary, and everything else he could do to lighten rotating mass. It also had a good deal of compression, twin plugged, one of the original Sifton cams with the weird names ("minus minus" or something like that).

What a strange bike to ride. With all of the familiar Harley flywheel affect gone, it was a far, far different machine. Riding it, one quickly learned to live in fear of any stop lights - taking off from a stop was a very real challenge. Being a kick start only, with all of that compression and those big cams, quickly re-starting it after killing it in an intersection was a "non-starter" (pardon the pun...).

Boy that thing was fast, though. And not just "for a Harley". In a rigid frame, running on a magneto with no battery on board (another reason it was "challenging" to start sometimes), no horn, minimal anything that didn't make it go, it was pretty damn light as well. He ate that generation of Japanese liter bikes for lunch. Granted, it probably had about a 15,000-20,000 mile service life, but what the hell. It sure surprised a lot of people.

Anyway, back to your bike. As a loaded, two-up touring bike, I again kind of have to wonder what advantage there might be in lowering the rotating mass. I really like that massive flywheel, kind of "lazy" affect on my Road King, especially with my wife and all of our stuff on board.

[Yorkie]

Keep ‘em coming. I’m learning a lot here. Thanks.

[Jeff Higgins]

Awesome! Looking forward to seeing your results.

I would like to hazard a guess, but could you do me a favor first? How about a build summary. I know it's an Evo but, beyond that, I know nothing. So - displacement, compression, cam specs, induction, exhaust, and that kind of thing might be helpful before I make my guess.

[afterburn 549]

Updates for those that care -
Finally got back at it!
The compression test reveals- 245 ( crank compression.)
This is a bit too high and bought the Woods W9 hoping it will drop the numbers
The only change was the Porting done by The dudes in Portalnd ..,so proper porting does change a few things!
It used to run like a Bat out of the proverbial Heill with the DM 530

I will get the W9 in and see what it is does.
Then head for the dyno.

[asphaltgambler]

What is the specs for the Woods cam?

[afterburn 549]

https://www.woodcarbs.com/cams.htm


Woods 8

http://bigboyzheadporting.com/EVOcams.htm

[!pse203]

I am gobsmacked by how much time and effort you have put into this.