As with anything theres always going to be different levels, @R-R-Rx7 is at a much higher "level" with his build and goals than most people here so I definitely understand the thought process of caring about every last drop of performance.

We already established the consensus is a no-go on vbands from the users here, but that new Artec vband manifold i shared looks appealing based on this mindset, they kept the runners divided right up to the flange, on top of keeping the wastegate runner fully divided up to the flange as well, I appreciate the extra detail and quality from the Artec designs and they have a good reputation from what I've seen as well.

 

I appreciate you sharing the Artec manifold. If it were somehow equal length runners, I think it would be a clear winner. If I am not able to convince Howard Coleman to make more of his manifolds, I think the Artec would be on my short list of manifolds to consider.

Maybe I am cheap as I am not considering the EFR series. For the money, I was thinking of the SXE or this new mysterious SXR to get me in the 550-600rwp range. While I understand the EFR might have a slight advantage with getting to boost quicker, I would rather spend the $1600 difference on more fuel. The SXE 66/91 looks very appealing as does both of the SXR's.

 

the other way to do it is to actually collect the relevant data and then let that tell you want turbo you need. on the compressor side, most of us have good enough data, you need inlet temp and pressure, and outlet temp and pressure (if you added turbo rpm you could draw your own compressor map) so we have a good idea of what compressors work.

however on the turbine side, most of us aren't collecting the full data set. you need essentially the same, pressure in, pressure out (pre and post turbo back pressure) and EGT in. if you wanted turbine efficiency, EGT out

you can let the data tell you what turbo to run