Hey Everyone,
Does anyone know anything about a H95 or a H75 oval port head ???


Thanks Bronte :)

there different combustion chaber sizes resualting in different compresion ratings i beleave

Ok cool thanks

no worries any time :P

Is there any other variations in the water jackets or thermostat housing ?

There's a huge write up here on all the different heads in the Tech-Wiki here it is: A-Series Cylinder Heads.

The H95 is probably more ineffective than a stock round port head for racers as it has a huge restriction in the ports just at the major turn into the cylinders (okay that's probably an over-statement so don't take that one as gospel, but you get my drift). This was intended to create a swirl effect and it was used as an economy head. Don't try to port the H95 out to get rid of the restriction, you'll end up finding water, sooner than you think.

The H75 is commonly referred to as the low-comp head due to it's combustion characteristics (large open cylindrical chamber surrounding the typical kidney-shaped combustion chamber) and sometimes because it actually has 2cc's more in each chamber than the H89 or GX head.

The H95 is 29cc per combustion chamber from memory, might have to check that though.

I think ddgonzal posted a picture of about 6 different thermostat housings, some have a differing number of bolt holes but they all share at least two common holes in bolt pattern so you should be okay using the common type.

Here you go.




The H75, once machined down to the second platform of the combustion chamber (removing the large open cylinder of chamber) can then become as good or as effective as a H89, port away, and spring it appropriately and it'll be a good performer.

Ok then thanks heaps for all your help..

:)

You didn't end up with that New Old Stock one off eBay did you?

This one here:

H95 Head on eBay

Sorry the H95 probably isn't 29cc- I have no idea. It has a pretty weird combustion chamber though.

Not that one, but one exactly like it.