It all depends on the power you want to reach. If you have 9.5:1 CR and a strong bottom end and your heads are similar to a set of Champion GN1's that have some cleaning up then you have a lot of potential for power. You can do a lot with a very small compressor. 140mph trap speed is possible with a 66mm compressor. A fast ramp cam that works with the heads and CR with the proper torque converter, and any p trim 63mm or larger compressor and probably a 62 billet (though not achieved here yet) and a lot of other little things will make 9 sec power with the everything right. More or bigger is not usually better for a street car. Id like to see the 62 trim ex wheel in the 9's. Im thinking its totally possible with the right combo. To squeeze it out of a small compressor you need a purpose built engine. The number one fail item item is usually the converter. I see so many spend thousands on everything else only to buy a $$500 or cheaper converter. When you do that you leave a lot on the table.
Common 3 bolt ex turbos and what id look for if i was building an engine and wanted to have the fastest spooling setup out there to achieve the mph shown with off the shelf cam grinds and 8.7-9:1 CR and other supporting items:
5831 Te44 120mph
6031 te60 122mph
6069 pt54 126mph
6076 60-1 128mph
6176 gt35 130mph
6262 133mph
6376 te63/te45 133mph
6265 135mph
6665 te45a/t64e137mph
6776 te67 137mph
7076 te70 138mph
6765 139mph
6680/68 GTQ/f1,HPQ 140mph
6780/68 GTQ/f1,HPQ142mph
7080/68 GTQ/f1,HPQ 145mph
7168 f1/HPQ 145mph
You need a lot more than a turbo to make power as you will see that most havent/cant even come within 5mph of the above. Some have gone much faster than the above. The ta49 (same as te44) has been at least 121mph on an unopened engine, i went 124mph with the pt54 and its been over 130mph, ive gone 127mph with the 60-1 and its been a lot faster on some imports, the 6365 has been 134mph, the 6776 has been 139mph?(John Crawford), ive been 137mph with the 6680 and on my way to 140+ with it but i hurt the engine (114mph eighth), 6780 has been in the 9's in total street trim with a stock ecm on alky/93 (Melissa/Grumpy), Cruz has been over 150mph more than once with the 7168. JW has been over 150mph with it also. There are a lot of others that have hauled the mail with a lot less than would be expected. For a street driven car with a 8.5:1 CR, the common 212 grind, a good converter, and some tuning you can save a lot of $ going with a 6265 or smaller and still have a decent spool up. Keep in mind that the the hp potential and tech era of the turbo almost totally designates how one will spool compared to the next or previous. More power will need more turbo which will spool slower on the street without more expensive and finicky crap thrown at it. If you are looking for 130mph with a 3.8 or a 4.5 id still go with the same turbo almost everytime. Maybe slightly larger on the compressor but the ex wheel would be the same. Build something that will burn everyones ass by staying conservative when choosing. 9 out of 10 times it will be quicker and more fun to drive.