Velocity and pressure must matter in this scenario of just the vac pressure to the gate. I'm wondering, I've got a T going to an mbc I ran out of the small tubing 1/8th maybe not sure and used a bit bigger down to my intercooler pipe. First I noticed when the line is too long it lags... So it's as short as it can be with its location.

Does smaller inside diameter tubing make for a faster responding and efficient source or its pressured and doesn't matter?

 

Technically the smaller lines means less to pressurize. And since the wastegate signal relies on pressure and not flow it sort of makes sense

 

I just looked at tial's website and they say 1/4" ID minimum... I would assume that the line does not allow enough flow if its too small. Also changing from 20" or so vacuum to 15 psi requires a flow of air, I would agree with the statement about pressure however you have to take into account vacuum which is a lack of air, so it must come from somewhere... ie flow into the line (hope that made sense)

 

It's worth playing around a bit. So generally a larger diameter tube would be better? This can make a difference and the way boost comes on so anyone also thinking check with your tuner.

B16 block going in thick gasket arp etc... Done at home on the road again soon! Thanks boosters