8 valve Rajo head compression ?

[FlyingZman]

I have an original ? 8 valve Rajo head, single spark plug, and carb heat port, system for my 26 T.
Building the engine and have not been able to find information about this head and if it is a higher compression head on a standard flat top piston.

Can anyone give me some information about this?

Thank you,
Zman

[Mark Chaffin]

Post a few all around pics.

[Kevin Pharis]

Can’t tell how deep the combustion chamber is from the pic lookin straight at the valves. Any brand overhead with lower compression has a combustion chamber depth of about 1.25” (4:1). With the higher compression heads measuring about .875” deep (7:1)

[Mark Chaffin]

Earlier style (Pre-26/27) Model BB. Chamber depth was originally 1 1/4". Looks as if it may have had a 1/4" or more milled off the bottom surface as they cut into the bottom of the spark plug ports. Very lucky they did not break into the water jacket when doing so. You can run either flat stock pistons or the domed for higher compression. However, since it has been milled considerably, I would not use the domed high compression as you will be asking for trouble. $$$$$$$$$ Looks like a nice head. If you require a complete rocker assembly, contact Gary at www.rockerarmsunlimited.com, located in Redding, California. Gary is no stanger to RAJO heads and can make you a compete assembly for a reasonable price.

[FlyingZman]

Thank you
I was going to setup to CC chamber but hoped someone could clue me in on this.
Have all the cards components for install so pretty sure I’m set to bolt on and adjust.
Not building a radical engine, but wanted some pep.
Thank you all again
GZ

[FlyingZman]

FYI
Made a measurement on combustion chamber
0.910” depth
Checked area on water jacket between face and inside.
You are correct
Not much meat left.
Will not be putting this one in races.
Thank you for your help
GZ