School me TIAL WASTEGATE

[Dj Ryderz]

So i'm about to buy a 38mm tial external wastegate.

But i'm a bit confused with the spring rate.

A plan to boost about 18-20lbs.

If a bought a 18lbs spring. Is that mean that im gonna have 18lbs of boost or its more complicated.

And an External is compatible with a boost controller right ???

And Everything else I should know about it ????

Thank

[Kelly.]

the spring you put in the WG will be the minimum boost you can run.

i would put in a 12psi spring in and run a boost controller

[s15specR]

^ what he said...

[jr_ss]

I'd throw the 38mm out the door and go with the 44mm...

[Kelly.]

I'd throw the 38mm out the door and go with the 44mm...
not completely necessary
the wastegate is meant to bypass exhaust gasses away from the turbo. if he was going to be running a big motor (such as mine) and running low boost (ie bypassing alot of exhaust gases) then a 44mm would be ideal.

on a high boost, small cube motor, a 38mm is fine.


fwiw - i ran 32 psi on a 1.6 liter honda with a 38mm tial, and with my greddy profecB boost was very stable.

[smelly240]

jr_ss = incorret

kelly. = correct

[pinkarrowsnow]

Ok here is it in simple format. Get a lower spring and if you have a boost controller it will override the spring psi whatever it is. For example. I have a 9psi spring on my TiAL if I hooked that right to a vacum sorce my car will boost 9psi if I have that vac line going into my boost controller then into the wastegate it will push whatever my boost controller is set at.

[sr20boostn20]

I'd throw the 38mm out the door and go with the 44mm...

i agree 100% . i had 3 of them, ever since i switched to a 44 i've never had a problem.

[Kelly.]

Ok here is it in simple format. Get a lower spring and if you have a boost controller it will override the spring psi whatever it is. For example. I have a 9psi spring on my TiAL if I hooked that right to a vacum sorce my car will boost 9psi if I have that vac line going into my boost controller then into the wastegate it will push whatever my boost controller is set at.

while normally this is standard practice,
i have seen some vehicles run into problems where the car is creating enough exhaust pressure to override a weak spring in the WG and leak exhaust gases, therefore hurting spool up.

as a standard now, i recommend running a spring that is ~2/3 of the max boost you plan to run so this doesnt become a problem.