ext wastegate sizes

[AMZ020]

hey everyone,

just wondering what people are running/thinking when it comes to external wastegates,
from what i have read the smaller the wastegate for high boost, larger wastegate for lower boost?, however from what ive seen its a case of bigger is better? im converting non vvti 1jz to t70 single and am looking at a 44mm gate is this going to be ok? what are you running? think of the performance?

[pandaah]

depending on what boost your running, what sound you want, and if you go about getting the correct wastegate spring for the boost you want.. 44mm would be a pritty good size for a t70, and with a 2inch gate pipe thats about 30-40cm cut on a 45degree on the end youll get a crisp cracking noise from the gate.. sexy!! haha..

just yeh, the key is to get the right pressure rated spring for your intended boost level otherwise spiking may occur

[AMZ020]

ok, it comes with 15psi spring, i will adjust to 14.5psi. does the size wastegate / pipe style make noise difference?

[slipway]

why not just run 15psi, .5 isnt much more you would need to change the spring to something like a 12psi and get a bleed valve to get 14.5psi

[Draven]

consider what the wastegate is for - it's for bleeding off excess exhaust gas to prevent the turbo spooling up too much boost.

So if you're after a low boost application, big wastegate is better.

If you're like me, and think adjustable boost is useful (like on a wet track), then even if you're pushing 20psi, a big (48mm) wastegate is great so you can wind the boost down and get yourself a controllable car under some circumstances.

[wilbo666]

Rule of thumb is:

* big turbo/low boost = bigger wastegate
* big turbo/high boost = smaller wastegate
* small turbo/low boost = bigger wastegate
* small turbo/high boost = smaller wastegate

Cheers
Wilbo

[AMZ020]

only reason i was going 14.5 is fuel cut, but am gonna go with a defender as well and just go for 16ish 44mm it is!