Massey 44

[scadam]

Just wondering whats the biggest u can bore an h260 block and still be reliable?
 

[MH55]

Define "reliable"...

4.5" will run all day. 4.875 will hold water. Have heard 5" is pushing it... May or May not hold water...
 

[scadam]

Well i wanna pull with it but i also wanna be able to ride in parades if i wanted to and wanna be able to pull it back to back if needed to also
 

[massey 333]

For what he says he wants to do,maybe 4.5"will be ok,but I sure wouldn't say 4.5"would run all day under a load of 35-45HP.
 

[dboll]

built up pulling tractors and farm/parade tractors don't mix very well
 

[scadam]

Well like i said it be a pulling tractor but if i wanted to parade it at a show i would like to be able to without it overheating
 

[LarryM]

Gary Herrell at Goldsburg Performance stated that he can build a 500 cid H-260 with full water jacket that can be driven all day long. If anyone would know he would.
 

[Goldsburg]

Scadam -

As long as you are running a full water jacket and do not have a leaking head gasket, any engine size will not overheat in parade duty with a "good" radiator, fan, and thermostat.

You have to remember that the cooling system only has to extract the heat being rejected to the water jacket to maintain heat balance. Parade duty would only require a few horsepower, so therefore the radiator does not have to reject much heat. By using a thermostat, you raise the temperature of the coolant and that allows the radiator to more easily reject that heat.

Anything up to (but not including) 5" bore runs a full water jacket in the H260 block.

Regards,

Goldsburg
 

[scadam]

Thanks gary i think im going to play it safe with 4.5" bore and 6.5" stroke should do all i wanna do