Cylinder head Chrysler 75 Hp

[ErSa]

Is the cylinder head from a 70 Hp Model 7071 compatible with
power head 75 Hp Model 757HB? The older cylinder head (7071) seems
to have more easy access to the thermostat. See enclosed pictures.
After searching the forum, I think I will find the answer in thread "

3 Chrysler heads compared. 70hp, 75hp, 85hp"! ​

 

[jimmbo]

I suspect the newer design offers better Cooling, which allows higher compression and/or more spark advance without detonation. and since the entire cover has to come off to access the Thermostat, it is more likely that the water passages will get a Cleaning

 

[Nordin]

ErSa, yes read that thread it will give you some information and as jimmbo says better cooling as the water will flow over and around the spark plugs.
But check what size of the head bolts it has.
Some of the old heads had lager bolts if you choose the older typ of head.

 

[ErSa]

Thanks for your advices. Now I have to choose between good cooling and bad access to thermostat or bad cooling and good access to thermostat.

 

[The Force power]

A stuck (halfway) closed thermostat = never good cooling