Erik Steinbring

I have a ZIPKIT JAE 21Rigger that I need to complete. Its been in storage for a year and I have forgotten a lot. I have a Rossi T21, header and pipe. I found the gauge that was supplied with the motor. Question is how much do I shorten the header?

Blackout

8" from the plug to the widest point on the pipe is a good start.

advanced builder

Make sure you get the coupler over that ring on that Cooper pipe ,She will slide off if not ,trust me I have one like yours ,8 1/2

Blackout

You can go a little long if you like. You will have more torque, but less rpm's. A longer pipe will be easier to come on and off pipe. Easier to start off long and slowly cut material off.... So as AB suggests, 8 1/2" might be a better suggestion for starting. Lower nitro, like 25%, will like a slightly longer pipe too. I am at 7 3/4" on my NR .21 with a AB pipe. I could go shorter, but I like the drivability at this length so was hesitant to cut shorter.

Erik Steinbring

Thank you for the help! Hope to have this boat running shortly. Im rigging it during the week after work, the honey do list is too long with a new house to play during the weekend.