Turbo's and Compressor Flow Maps

[90AWDTalon]

Yesterday I found out I need a new turbo and exhaust manifold. My original plan was to do all the supporting mods and then save up and get an AGP L1R. Thats not going to happen now. I'm basically trying to decide between small 16G and Big16G. I was thinking Big16G at first then I started looking at some compressor flow maps. I'm a beginner when it comes to flow maps so I don't know if my logic is working so I need some input from you guys.

My goals are to have a daily driver that can run mid to low 12's, and have as close to zero boost lag as I can get. I plan on doing more autocross than drag racing. I think the quarter mile goals are possible with either turbo. Looking at the flow maps the small 16G looks more efficent than the Big16G untill the boost gets turned up much higher than I ever plan on going. They both look like they produce similar flow at the boost I'll be running, but the small 16G is at higher efficency. Am I right in how I'm interpretating these maps? How much faster does the small 16G spool than the Big16G?

Any input anyone can give would be great.

I still plan on doing all the supporting mods, just after turbo upgrade now instead of before.

 

[90AWDTalon]

also I plan on getting the same options no matter which of these turbos I get.

Ported
38.1mm flapper

 

[candela]

Well in your case maybe you shoud jus tgo with the small. You are right it is more efficient at boost levels, for the most part, below 19psi or so...
From my setup to a friends, my Big16g spooled faster. Im not sure what it woud be like on an identical car, but if you port everythign very nicely and have 2g pistons or even 1G's I guess, you can expect about 15psi at around 3-3100rpm... my big 16g got it at 3150 and that was 18psi.
I dotn see any need to get a 38mm flapper with a 16g at all. A 34mm shoud lbe plenty fine for that turbo, it was for me and is for many

 

[kpt4321]

You are correct sir! The small is more efficient until a certain pressure "cutoff", which I seem to emember being in the low 20's....

Think twice before you buy a WG flapper that big. When you have a lot of surface area, the total force on the door is going to be rather large, probably large enough to blow the door open with a regular mitsu WGA. That's never good.