External Wastegate size ?

[eXploitedGST]

alright im lookin at external wastegates outta curiousity and seeing that they come in a couple different sizes. AGP turbocharger has 3 different sizes. 35mm, 40mm, and 46mm. What exactly does it matter for what size you get anyways? is one size better than the other. id assume the larger the port the better cause then id allow the exhaust to get out without get backed up and spooling the turbo more than you want it. any ideas here?

 

[Black95GSX]

35 is fine if you mount it on the manifold and vent it....

otherwise you'll need bigger to vent more backpressure

 

[L2RTSiAWD]

I think 40mm should be fine for anything up to the L3 turbos then I would switch to a 46mm.

 

[Black95GSX]

Yeah yeah yeah internal wastegate boy.

My 35 works fine on my T3/To4e

 

[Black95GSX]

Keep in mind if you mount the external on the o2 housing you'll need a larger gate, due to the fact that it must work harder to do it's job down there.

 

[L2RTSiAWD]

Hey now. Noone mounts it on the manifold anymore.

O2 housing is where it's at nowadays.

 

[eXploitedGST]

why doesnt anyone mount on the manifold?????? what if i got a different turbo and manifold that didnt use the o2 housing then how would i mount it?

 

[L2RTSiAWD]

I was joking sorta.


Back in the day manifold mounted is what everyone used then someone started the o2 mounted craze saying it controls wastegate gasses better and can vent exhaust after all 4 cylnders. instead of 1. so It's all up to personal taste.

 

[Black95GSX]

Look at my manifold, it uses all 4

Problem with o2 housing mounts is they are harder to control -- that is why a lot of the new setups use manifold mounted, look at RRE's pics on their site.

 

[L2RTSiAWD]

If it's manifold mounted all i can say is get an SFP manifold.

 

[ILOSE]

An external is not neccessarily turbo size dependent, To a point! The size gate you buy should be more based on the amount of boost you want to run. The lower the boost psi, the larger the gate needed.
now if you were running a T88 you would still need a large gate to prevent creep and control boost more precisly.

What size or turbo are you running?