OH NO ANOTHER 5th/6th port thread!!!

i have an NA, and i currently have the 5th and 6th ports wired open. i want to weld a bung onto the exhuast for activation of these.i was wondering where would be the best place to do so? on the header,midpipe? before i started drilling and welding i thought maybe someone else has done this and achieved good results (not opening WAY late or WAY early). i have a custom header,straight midpipe to two mufflers (no cats or any restrictions).

 

Well, just having a bung usually isn't good enough. The RB units come with a tube with a c shape. The bottom half of the 'c' actually hangs down, so that exhaust gas can flow into the c, and up into the UIM to activitate the aux ports.

 

Exhaust backpressure is a terrible way to operate the ports with a modified car. Any reduction in backpressure over stock means the ports open later than they should. You have no control over when the open, so you're almost guaranteed to be losing mid-range perfromance as a result. The factory system is calibrated to work properly on a stock car only.

Look for the many threads on electronic actuation using an air pump, a solenoid valve and an rpm switch.