New 18cc clone head.

#1
I saw this on Bobs it is a copy of the old Honda head and Mike from cloneenginepartsonline.com has them for sale. While I still like the hemi it lacks a squish area unless welded which causes other issues. This head has two squish areas and a sort of fast burn design with tapered walls. This allows a good amount of CC reduction without excessive milling. I am going to baseline this head on the bench and take molds of the ports then make a big valve (32/25) head out of it and retest.

 
#3
I saw this on Bobs it is a copy of the old Honda head and Mike from cloneenginepartsonline.com has them for sale. While I still like the hemi it lacks a squish area unless welded which causes other issues. This head has two squish areas and a sort of fast burn design with tapered walls. This allows a good amount of CC reduction without excessive milling. I am going to baseline this head on the bench and take molds of the ports then make a big valve (32/25) head out of it and retest.

I have a few too.. I just put a seat and a 28.5 valve in one today, I hope to flow it tomorrow..I will be doing a 32 as well
 
#4
Warm weather today so I went out and took molds of the ports. Attached are the intake exhaust and the hemi intake for comparison. The hemi port has a bigger valve bowl and valve seat and less of a turn from the port runner into the bowl. The new head has the bowl and runner in line and the short side height is equal along the bottom where the hemi has the bowl tilted relative to the runner so the short side height is shorter on one side than the other. On this head I will raise the top of the runner and radius the long side and depending how much I can raise it may fill in the floor at the entrance and taper it down towards the short side.

 
#6
Great pictures! Care to share what durometer casting compound you use? Curious to know if I want to be able to do the same and pull the casting in one piece
 

delray

Well-Known Member
#7
have to go to that web site and check it out. wonder what kind of bolt on compression you would it with a flat top and .010 gasket(base on a honda engine) and what size are the valves and is there any options on valve size or cut them your self.
 
#8
It is very easy to do, I bought the stuff from US composites very nice people to deal with It is the first one on this page Molding Rubbers

Release spray on this page
Mold Releases

I spray the port with the release stuvv as well as the back and stem of the valve then put in valves with stock springs and retainers to hold them. I next hold the head in a dremel vise that swivels and locks so the port is upright. I glom some mixing cups from mcdonalds and fill them about 3/4 full (two cups one hardner the other the liquid urethane in equal parts) then pour it into a small drinking cup and stir. pour it in the head port and the next day you remove the valve and using my thumb push it at the port and the whole thing comes out the valve area. It would be even easier the other way but it is real easy to get out. It lets you visualize what areas you want to grind on and if you cut the rubber mold at its narrowest point then lay it on graph paper you can count the 1/4 inch squares and figure out the Sq inches of area and from that what the maximum flow could be. After I port a head I take another mold to see what it looks like. In the hemi head I did I did that 4 times till I got it where I wanted it.
 
#9
I keep looking at those lovely castings and cringe at the thought of just how much work its gonna take to make the Hemi work right

So much weld and epoxy I don't know if I can even buy valves long enough to fit when I am done ( And nothing even cooked up to address the valve geometry issues after ).

These are really excellent castings though, they show just what we are up against in all the Clone heads.
 
#10
I keep looking at those lovely castings and cringe at the thought of just how much work its gonna take to make the Hemi work right

So much weld and epoxy I don't know if I can even buy valves long enough to fit when I am done ( And nothing even cooked up to address the valve geometry issues after ).

These are really excellent castings though, they show just what we are up against in all the Clone heads.
Just go buy a Champion 208cc at TSC and you will have a 18cc head with 27/25 valves... :)
 
#11
Just go buy a Champion 208cc at TSC and you will have a 18cc head with 27/25 valves... :)
TSC does not have the Champion any more up here in the nickel city.
But I do have a head close to that from a PA 208 ( its larger than 18cc. )

That said I am committed by my stubborn pride to make something of this already welded head, its simply going to take more.
And I may have to port to death several hemi heads to understand how much material I can remove from the bowels ( or Bowls, depends on your feeling toward the head at this point ).,

And the Canadian Peso's relative value does not make the import of parts appealing at this point as well.
 
#12
Flowed the head and it was the worst of any of these clone heads I have tested. In addition The intake really made some terrible noises on and off and I had no real success finding out where it was going turbulent. I did find one spot in the floor about the middle of the ssr where It would pickup a tiny bit but the noise really was troubling. I flowed the exhaust backwards so it is not really accurate but no great shakes there either. Well on to installing a larger seat and porting.
 
#14
Cant take the cold anymore. Yesterday it hit 86 degrees. I have been waiting for warm weather to finish painting my rupp and fox frames but yesterday and today it was so windy there was no chance of any painting outside.
 
#15
Warmed up around here.

Snow is wet and sloppy now and I am just starting to notice how deep the drifting has been recently.
Snowblowed around my work shop....
Dog has been avoiding the deeper areas of snow to poo..

You know I am really tired of winter now myself not so much because I hate the cold I am just tired of what the snow hides and reveals as the melt begins.

More snow on the way however, and the snow blower needs a real good cleaning this spring.
 
#16
Flowed the head and it was the worst of any of these clone heads I have tested. In addition The intake really made some terrible noises on and off and I had no real success finding out where it was going turbulent. I did find one spot in the floor about the middle of the ssr where It would pickup a tiny bit but the noise really was troubling. I flowed the exhaust backwards so it is not really accurate but no great shakes there either. Well on to installing a larger seat and porting.
I flowed one as well.. nothing special at all (as expected). I have done one with a 28mm valve, and one with a 32mm valve.. they both turned out very nice.
 
#17
Barry I wanted to try a 32mm insert but just trying to center it over the existing seat I will have to machine away chamber wall and was wondering if when counterboring head for the insert would I hit air. Did you have any issues cutting the seat pockets for the 32mm insert?
 
#18
Hey Prowler:

Those Champion 208s come with stamped steel rockers or the older forged style?

Are the stamped steel type same as the G200 predator hemi type casting?
If I am looking a the pictures correctly they appear identical and interchangeable.

How do they hold up against a cam with more lift?
Can you run a 290 on that and are you using longer valves like a predator to achieve it?

I shimmed the older cast rockers as required for geometry in the past with no issues.

What is the deal with the powercube 208, I was looking at that this weekend.
looks like a Champion, some of the generators marked powercube have champions on them too.
 
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#19
Barry I wanted to try a 32mm insert but just trying to center it over the existing seat I will have to machine away chamber wall and was wondering if when counterboring head for the insert would I hit air. Did you have any issues cutting the seat pockets for the 32mm insert?
I didn't have any problems with installing the 32mm valve seat.. I unshrouded the chamber as well.. it is going on a 2.815 bore, so I had room to get it nice.
 
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