Radiator cap pressure

[Chris Kennedy]

Hi:

I have a stock Superformance MKII that uses the Roush 427 SR engine. I use the car on the street---no track work. I am wondering what radiator (head tank) pressure cap pressure people are using.

Thanks for your help,

/s/ Chris Kennedy

 

[Howard Jones]

Here: I use a 16 PSI cap. It seems to work fine. There is no reason that you can't keep the coolant temp under 260F in an engine that is working properly. That would be the boiling point of coolant (2/3 water 1/3 antifreeze). If it's over that then it can only be uncontrolled airflow, the pump isn't running efficiently or it is underfilled with coolant.

Note: The oil cooler and its related system are a big part of the total engine cooling capacity

What Pressure Radiator Cap Rating Should I Use?

What Radiator Cap Pressure Should I Use? We are asked this question daily and most people misunderstand what the pressure cap does. The cap’s pressure rating has nothing to do with regulating your engine’s coolant temperature, nor will it make your engine run cooler. Depending upon the original...

www.dewitts.com

RADIATOR CAP, 16 LB.

14-18 lb Racing Radiator Cap

www.moroso.com

 

[Chris Kennedy]

Thank you very much for your reply----coincidentally, I was looking at this cap or the one right below it!

Regards,
/s/ Chris Kennedy

 

[Ryan L]

I think I have a radiator cap from one of the last AU III falcons in Australia for mine, and that only runs a pressure spring in the region of 13 or 14psi if I remember correctly.

IE this was all the ford Australia deemed necessary on the V8 falcons.

The rating of the thermostat is probably more critical in terms of when it opens and how hot it lets the engine run. If you just using it as a street car, I would assume that keeping it cool and not stressing it is more important than out and out performance, so not chasing the last few HP that may be gained from a hotter engine, increased clearances, or hotter combustion cycle?

 

[Chris Kennedy]

Thanks---yes, you are correct, and I appreciate the reply.

/s/ Chris Kennedy

 

[Bill Kearley]

Where do you live Chris. If you don't live in a very hot area and it's easy to keep your cool a 13-15 lb cap is fine.

 

[Lee Patterson]

Chris - many of us Pantera owners use a 16lb cap. I use a Stant 10230 and live in San Diego.

 

[Chris Kennedy]

Where do you live Chris. If you don't live in a very hot area and it's easy to keep your cool a 13-15 lb cap is fine.

Thanks---I live in San Diego, and am closing in on about a 15lb cap. The car does NOT overheat or run warm---I'm pleasantly surprised at that! I have run out to the desert in it to the east of here as well!

/s/ Chris Kennedy

 

[Chris Kennedy]

Chris - many of us Pantera owners use a 16lb cap. I use a Stant 10230 and live in San Diego.

Hi---I live in San Diego, too, and as I mentioned in a previous post the car does not run hot, even going east into the desert. I really appreciate the suggestion!

/s/ Chris Kennedy