Originally Posted by vinniekq2
PJ, when were the tri Ys popular? I think Jere made the 4 into1s starting 1964? just before my time...lol.
I saw the first in the early 60s, at Detroit drag way they called em 421s (4 into 2 into 1) I think they were made by Cheetah Or Black Jack! LOL
My dyno tests were in the the mid 80s! But they were really popular in the mid 70s and early 80s here! and are still produced! they were also used on a lot of Honda 750 racing motorcycles!