Ken,
Not sure if the k&b carbs I have are what your looking for but I have two. One is for the 7.5 and the other is for the .67, .82, .91. Both of these have a neck diameter of .625
Let me know can send you pictures if you like
Scott
Gents,
I am in process of building a Roadrunner 60 rigger with the following set up:
CMB 67 HR
H-38 prop
AB parabolic pipe or CMB 60/80 pipe
50% nitro
What is a good starting point for the tuned pipe (each choice)?
Thanks
Scott
Tom,
I am currently running the 91HR. Still a very competitive engine (with light modification) in my opinion. You can install a VAC front housing on your HR if you want.
1667 prop is my favorite.
Scott