Anything Wrong with using a small Rad Cap?

[j-c-c-62]

So I have a new Alum crossflow rad I am installing, I am making some mods to it like moving/changing the in and outs to AN fittings, and removing the trans cooler.
I'm not happy with the existing fill location/design, so I want to mount one on the top of the end tank. I purchased a small style pictured below for no special reason vs a regular size.
Is there any real downside to small radiator inlet caps that I overlooked?

 

[ckessel]

If it's rated the same on pressure, I wouldn't think so. But then, I'm not an engineer. Maybe "The" engineer will chime in and regale us with vast amounts of knowledge.

 

[6PKRTSE]

I used a standard type neck on my radiator with Stant Racing 28-32 psi cap and a -6 weld bung and over flow hose. I also added -20 upper and lower weld bungs fittings on my radiator with AN hoses.

 

[RR Fan Dan]

If it's rated the same on pressure, I wouldn't think so. But then, I'm not an engineer. Maybe "The" engineer will chime in and regale us with vast amounts of knowledge.

Just my opinion.

 

[j-c-c-62]

If it's rated the same on pressure, I wouldn't think so. But then, I'm not an engineer. Maybe "The" engineer will chime in and regale us with vast amounts of knowledge

It's marked "1.1", so I assume atmospheres or 16psi?. I hope they make higher ratings for that size, but its a good starting point I suppose..
I'm converting the car to E85 and not sure what heat range it will finally be in.

 

[RJRENTON]

Just my opinion.

Not to disappoint.....the pressure rating is determined by the spring above the sealing disc not the diameter of the exterior handle the part with the "ears" or the color.......but.....that's "just my opinion"........
BOB RENTON

 

[Vaanth]

It's marked "1.1", so I assume atmospheres or 16psi?. I hope they make higher ratings for that size, but its a good starting point I suppose..
I'm converting the car to E85 and not sure what heat range it will finally be in.

The 1.1 marking on the radiator cap refers to the pressure rating in bars. A bar is a metric unit of pressure equal to 100,000 pascals (100 KPa), or 0.987 atmospheres. One atmosphere equals 14.69595 pounds per square inch (psi)

So, for the cap pictured, 1.1 bar = 15.95415115 psi, or ~16 psi.

Is there any real downside to small radiator inlet caps that I overlooked?

Likely no real downside to a small cap and inlet other than not being able to use more common "standard" size caps, or you might not be able to use these maintenance items, if you have them:

 

[j-c-c-62]

The 1.1 marking on the radiator cap refers to the pressure rating in bars. A bar is a metric unit of pressure equal to 100,000 pascals (100 KPa), or 0.987 atmospheres. One atmosphere equals 14.69595 pounds per square inch (psi)

So, for the cap pictured, 1.1 bar = 15.95415115 psi, or ~16 psi.



Likely no real downside to a small cap and inlet other than not being able to use more common "standard" size caps, or you might not be able to use these maintenance items, if you have them:
View attachment 1871417

Thank you, good reply. I do see why you have a nice positive reaction ratio.
But I do have the bragging rights my cap is lighter than yours.

One thing I do need to research is to confirm I can locate higher psi ratings than 16 in a smaller cap.
I haven't fired up the welder yet.