if it was overgated, he would not be able to make the boost he wants to, and that isn't the case, he's overboosting. Or it would dump a large portion of the boost when the gate cracks and that isn't happening either

we've run 4 cyl twin scrolls with 4, yes 4 V60's

 

Well, for comparison's sake the same could be said about the internal wastegate passage(s) on the MHI 10.5 turbine housing. The waste gate bypass port(s) on the stock turbine housing source at 90 degrees off the turbine inlet area. Even so the stock wimpy internal gate alone diverts sufficient exhaust flow tangentially to control boost in most all cases on a JB FP Black. So, why can't twin remotes with more than double the valve surface area control boost in this scenario?

 

it's not 90*...it sticks out IN the flow path to collect the gas, I mentioned this in previous posts

 

OK. this is where it gets interesting. I imagined that he was in fact dumping too much exhaust volume when both gates cracked. Thanks for clearing this up.

 

this is an ideal setup for a wastegate

 

Thanks for taking the time to explain these details to me. You did mention this earlier. The fact that there is this flow path obstruction.

The header is poorly designed especially with respect to how it is flanged then?

 

the header itself is fine

it's the angle at which the flange is mounted, if it were transitioned in and the exhaust gas could flow to it freely it would work great.

 

i guess i will put a bigger spring in the gates and hope for the best.

on a side note... my friends honda civic b16 turbo with a divided setup had an issue on the dyno as well. the 2 mvs wastegates had the black and red spring (i believe 1 bar) and it gave him 30psi on the dyno.

 

don't get me started on most Honda manifolds lol

 

Is the spring chart different for MVS compared to a standard 44? His .5 bar spring isn't opening until 19psi on a bench. That's close to where you stated a 1bar should start to open.

 

for an MV-S that is normal 17-19psi

all of the gates will be different because of valve diameter differences and diaphragm area differences

 

I'll see if i can get a sheet made up of cracking pressure for all the gates on a test bench

 

thank you