Brand name "T61" vs Holset 60mm turbos differences? physicialy and capabliltes

I'm needing some opinions on my build, here's an overview:
5.3 lm7 with turbo cam, arp bolts, ls6 intake, and supporting stuff.
4l80e
Twin turbo


I've narrowed down my turbo selection to something around the 60mm mark. Here's my dilemma, I'm able to get Holset turbos for $75 a pop. With this in mind, I would lean towards something like twin he351's with the 9cm exhaust sides and slap a tial 38mm before each one. The beauty of this is I can buy numerous he351's and always have a backup if one fails. Very cheap.

However, I'm FAIRLY limited on space (not terribly, but it's not an old truck or anything with crazy engine bay space) and I don't want to add astronomical amounts of weight. I'm already adding a good amount going with the iron block and big 4l80e. What difference in physical size would the he351's be compared to, lets say, a master power t61/t64? What about weight? I want to say it'd be a few inches each direction and maybe 10-15 lbs a piece?

Any and all input would be great. Also, if you think a different turbo would be better let me know. Not getting crazy with my budget though.

Thanks!

 

Re: Brand name "T61" vs Holset 60mm turbos differences? physicialy and capabliltes

below is a Master Power Race catalog with wheel and turbo measurements

http://www.hevosvoima.com/foorumi/files/mp/MasterpowerPerformanceKatalogi.pdf

if you need the old master power specs i can get those as well