sbc ideal water pump pulley diameter?

[cv67]

Have a RCR (jones) pulley system, love it.

Always had an issue with rad. hoses seeming rock hard like theres too much pressure.....while looking at the pulley it occured to me it may be too small..Dount its cracnkcase pressure engine has less than 100 mi no sign of that...So if its spun too fast along with a high volume pump could that be the cause?? Water moves awful quick through the radiator..Id think slowing it down would solve this issue and help it run cooler to boot.

Suggestions?

camino2007.jpg

[pdq67]

Imho, the closer to the stock OEM pulley ratio's that you can get, the better off you will be.

Why? Because our beloved engines were designed to be this way.

pdq67

[BillK]

If I remember my engineering classes correctly from a million years ago the only thing that will increase pressure in a closed system would be increased temperature. Increasing the water pump speed would increase pressure going into the front of the block but then it would be balanced on the other end and the overall system pressure would be the same.

Of course in an automotive engine if there is a combustion leak it would change the game completely. I think the first thing I would do is a combustion gas check before you spend a lot of time on pulleys.

If the pump had an unlimited external water supply then things would be different too but this is a closed system for al practical purposes.

[rustbucket79]

An engine at 200 degrees with the rad cap sealed is going to have stiff hoses.

[pdq67]

Don't our engines run upwards to 220 or so degrees UNDER pressure??
But right, I would run a 160 degree T in the summer and if I remembered to switch it out when it got cold, change coolant and put a 180 degree T in.

Oh, and in real cold weather I would close off like 1/4 of my rad. with a piece of cardboard to hold my engines heat. It would warm up and I would remove it....

pdq67

[Geoff2]

Pulley ratios: www.stewartcomponents.com

[cv67]

Maybe I need to do a leakdown who knows maybe theres a crack somewhere?
Last time I shut it off it was around 190-200..I could hear bubbling of some type in the radiator, dont know if it was boiling, hopefully not air.
Time to pull plugs again.