Author Topic: Boof Head of the week  (Read 1434 times)

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Offline bear

  • Vale Bill McIntosh ......"illegitimi non carborundum"
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Boof Head of the week
« on: August 07, 2011, 03:56:42 AM »
Ok fellas,
I know you blokes wouldn't do something this dopey but I thought I should share.
We quite often mix and match different heads and cams on our motors.
But we try to run a CR between 13:1 and 14:1 with all of them.
Our "big motor" has been the exception.
And it has proved to be nothing but a pain in the rear.
So it was decided to use a head with larger combustion chambers and valves with a radical long duration cam we had previously used in one of our smaller motors.
But the main aim was to lower the compression ratio to an acceptable level.
To put not to fine a point on it we cocked up the math.
The result was to high a CR and our valve pockets  were cut way to deep.
When we fired the old girl up she popped two pistons straight up and filled the shop with oil smoke.
Not quiet the result we where looking for, oh well. :-\

Cheers,
Brian

« Last Edit: August 07, 2011, 04:08:11 AM by bear »
The older I get the faster I was.

Offline Bill/BentON Racing

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Re: Boof Head of the week
« Reply #1 on: August 07, 2011, 05:35:40 AM »
Was time for a LARGE brew!!! Sh*t happens,damn.Are you using hy-vo cam chain set up? Mo details if so.Thanks and good luck,if you usually run 13-14-1,what was it at? ;D Bill
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Offline bear

  • Vale Bill McIntosh ......"illegitimi non carborundum"
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Re: Boof Head of the week
« Reply #2 on: August 07, 2011, 10:36:31 AM »
G'day Bill,

I think there where too many brews had while we where doing our math, that was the problem.
All the calculations done on the back of an EMPTY beer box. ;D
Both our race motors are Hy-Vo's.
Previous CR was just about at saturation point @15+
What would you like to know re the motor?

Cheers,
Brian

The older I get the faster I was.