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In the interests of 250 development...


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StephenRC45
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In the interests of 250 development...

Mon Aug 31, 2009 5:43 am » Post: #1 » Download Post

I've been cutting things in half!



More to follow.
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fontyyy

 
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Mon Aug 31, 2009 6:41 am » Post: #2 » Download Post

Are those centre plug heads you occasionally see on Yahoo Japan real Honda/HRC or are they home made ones?
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StephenRC45
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Mon Aug 31, 2009 8:20 am » Post: #3 » Download Post

Thats a stock head Wink

I'm not going to cut one of my HRC ones in half I can promise you!

Thats infact the reason I cut them in half. I wanted to know if you could mod stock ones to HRC spec. Answer, no. Not unless you do a lot of welding.
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fontyyy

 
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Mon Aug 31, 2009 6:12 pm » Post: #4 » Download Post

Ah, the question was not "is the head in the pic HRC .......", the question was "are the centre plug heads you see on Yahoo Japan HRC or home made"?
I can see the head in the pic is a normal one.

The question now as I guess from your answer there are HRC true centre plug heads is "did HRC make them from normal heads and therefore can someone else?"
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StephenRC45
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Mon Aug 31, 2009 6:56 pm » Post: #5 » Download Post

HRC did make heads but they did not use the same casting as an OE head (this was what I was trying to find out).

You could make one using a OE head but it would involve welding a rather large section back into a stock head then having it remechined.
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StephenRC45
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Mon Aug 31, 2009 9:32 pm » Post: #6 » Download Post

Heres a picture of a HRC MC18 rear head.

As you can see the OE spark plug location is still there but never mechined.

However you can not relocate the spark plug as HRC have done in a stock cylinder head as there is no material there! (see first pictures). Cunning stunts!



A set of these have found their way onto my R6K Wink
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Kieran

 
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Tue Sep 01, 2009 6:42 am » Post: #7 » Download Post

OK, now lop off an MC21 head.
Go on.

I dare you... Wink
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StephenRC45
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Tue Sep 01, 2009 6:49 am » Post: #8 » Download Post

It's already been done. As I said. More to follow! Very Happy
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StephenRC45
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Tue Sep 01, 2009 8:48 pm » Post: #9 » Download Post

Cut-away MC21 head.

Shows increased water jacket compaired to the MC18 and reduced head material.


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RZRob1

 
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Guilty Conscience

Wed Sep 30, 2009 3:30 am » Post: #10 » Download Post

It's all in the name of "development" of course, but I can't help thinking you're feeling guilty about taking these items out of circulation.

That said, what's next?

RZ Rob
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