Author Topic: Briggs 31 ohv compression  (Read 238 times)

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Offline cable1981

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Briggs 31 ohv compression
« on: November 04, 2017, 07:29:29 AM »
Looking to help bump my compression up a little bit, trying to squeeze every ounce of power out of my engine that is allowed by our rules ( stock crank, cam, valves, no billet this or that ect ect itís all stock).
Now Iíve read on here about swapping heads to help raise compression. Problem is, Iíve read to use a stock 28 head, Iíve also read use a 33 head.
Iím looking for some input. Is one really better than the other? Which will give the most benefit over the other?



Offline crazycraftsman

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Re: Briggs 31 ohv compression
« Reply #1 on: November 04, 2017, 12:28:56 PM »
The 33 is a better head but you would have to cc 28/31/33 head to see if there is a difference in camber size
owen
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Offline cable1981

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Re: Briggs 31 ohv compression
« Reply #2 on: November 04, 2017, 01:51:07 PM »
The motor is a 31 ci ungoverned, stock crank cam rod valves rockers, itís all stock with the exception of the .020 piston and .060 shaved head, all per the limitations of our rules. Just trying to squeeze the most out with the limited options for improvements.


Offline PJG56

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Re: Briggs 31 ohv compression
« Reply #3 on: November 05, 2017, 07:32:23 AM »
There is a 28ci head that has a lot smaller combustion chamber than the typical 28-31 head,
33 combustion chamber is much larger.
If you could locate the small chambered 28 head and do a good valve job would be your best bet.
Paul Guptill  (oppy) #238modX
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Offline Srutinrun

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Re: Briggs 31 ohv compression
« Reply #4 on: November 10, 2017, 12:44:53 AM »
It's a great compression too.

 

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