What are the differences between ZT and GX SU carbs, according to power, powerline, and mpg? I've never heard of GX SU's and it sounds very interesting.

GX was the group of high performance parts, developed by Nissan

ZT is a carburetter rebuilder/restorer

Mr. Purdue wisely had his GX's rebuilt by ZT

What are the differences between ZT and GX SU carbs, according to power, powerline, and mpg? I've never heard of GX SU's and it sounds very interesting.

Here's a couple of scans from old Datsun Competition/Nissan Motorsports catalogs. The first one is the GX setup and the second one is the 40 mm Mikuni setup. They also had a 44 mm Mikuni setup for these engines as well as a lot of other hi performance parts.