Different tube sizes in loop

[Livesundersink]

I was wondering if mixing different sizes of tubing has any noticeable effect on performance. i ask this because i am putting a custom loop together and have a radiator with 1/2 inch barbs whereas the rest of the kit has 3/8 inch fittings, the kit itself has a radiator with 3/8 fittings on it, i would like to know if i am able to use both rads.

[Shadow_Storm56]

1 hour ago, Livesundersink said:

I was wondering if mixing different sizes of tubing has any noticeable effect on performance. i ask this because i am putting a custom loop together and have a radiator with 1/2 inch barbs whereas the rest of the kit has 3/8 inch fittings, the kit itself has a radiator with 3/8 fittings on it, i would like to know if i am able to use both rads.

It's no big deal at all..... pressure will be higher in smaller tubes and lower in big ones. Flow will be lesser but likely more than if it was all small because of pressure changes. Basically flow will be more than small but less than big, if you wanna think simple just treat it as if it is limited to the flow of the smaller tubes. I mixed tubes before...no issues

[Blai5e]

Jay2cents stated that the difference isn't really measurable albeit he was talking about hard line tubing at the time. The other thing to consider is the fittings, in the standard size is G1/4 and that doesn't change no matter what your tubing size is attached (in the case of EKWB fittings, the inner fits a 9mm Allen key) so that's your limiting factor. In addition, you need to account for the resistance introduced by the water block(s).

 

So... what can be taken away about the above? Your pump head pressure is really the limiting factor and what size tubing (to a degree) is a superfluous to the equation.

[Livesundersink]

11 hours ago, Blai5e said:

in the standard size is G1/4 and that doesn't change no matter what your tubing size is attached

the fittings are G1/4, the tubing sizes are what i was quoting. sorry for any confusion

[Blai5e]

What I'm saying is that the G1/4 fitting is going to have a particular inner diameter and therefore, it's more than likely going to be smaller than the tube's inner dimension.