ericwilloughby

Another update. It wasn't necessarily the line itself that is the restriction. Turns out the quick disconnect fittings GM uses to connect the evap tube to the metal line are only 3/16" ID. I removed the one in the engine bay and just slipped the hose over the line, without a barb, and got my restriction down to 9 psi. There is another at the rear axle but it goes up to the tank so I left it alone.

Marc 85Z28

iTrader: (8)

Use the factory venturi system. I modified my 400 just like Racetronix does with their 255. Drill a hole and press in a barb.

ericwilloughby

Drill a hole in what. Press a barb in what

Marc 85Z28

iTrader: (8)

The pump! What else?

Drill an 11/32" hole in the top of the Walbro pump in the same location as the factory pump's barb. Carefully remove the barb from the stock pump by cutting it out (do not pull on it) and press it into the Walbro.

ericwilloughby

First I've heard of it. Don't know if i want to drill a hole in a new pump.

ericwilloughby

Don't use the Walbro F90000262 with E-85. The brushes dissolved in 2 months. This is the white sock i cut open after the pump failed.