I'm using a similar elbow to this
https://www.cxracing.com/EB-T4-300V-CAST-WG-C_VB_1-1_KIT?search=vband&page=2
Race only 406 sbc with twin gt45's. 8000 rpm max. Would like to be able to dial down the boost for slower bracket race days. What size wastegate minimum?
I will be using two wg's obviously. I know of some 38mm JGS's that I can get used. But I suspect that those are far too small.
How big do I need.?

 

I should have mentioned. High boost for me will probably be 16 psi. Like to be able to dial down as far as I can depending on the race and the track conditions. In n/a form, this engine runs 7.90 @167. Light car of course. I want to get a little more tuning experience at low boost too before getting aggressive with it.

 

Go as big as you can fit. You wont find any real disadvantage to one that is to large, but one that's too small wont allow you to meet your goals.

 

As with everything there is a balance. Too small and it cant reduce pressure, too big and you can't keep the gate shut. Placement has more to do with control than size IMHO. I would think twin 44-ish would be plenty.

 

X2, what Disney said.