Weber Conversion ?

Guys,

I am new to this forum & recently bought a 1981 Plymouth Arrow truck with the 2.6l. It has been a nightmare so far with one problem after another but $1200 later & a laundry list of new parts I think things are looking better. I just did the Weber carb conversion yesterday. The truck seems to be running pretty well but I have a few questions. 1st (& most important) is what to do with the 2 "OUT" lines on the stock fuel pump. The Mikuni original carb used both lines but the Weber only needs 1. The Weber Tech guy told me to hook the return line, that ran off the driver side of the Mikuni & went back to the tank, to the extra fuel pump line. It seemed logical. Is that what other guys have done? I noticed that my fuel tank is building up a lot of pressure now. I did not have the truck very long before the motor came apart for a new head gasket thanks to a previous owner hiding it when I bought it so I don't know if the tank did this before. I thought about venting the gas cap but really would rather figure out what is causing the pressure. I also added an inline fuel filter between the pump & Weber to help lower the fuel pressure & it seems to be fine. How crucial is hitting the 3.5 psi that the Weber calls for? Can I keep the stock fuel pump & add a regulator? How do I know if I am getting too much pressure to the carb? Any help at all is greatly appreciated. If possible, someone could PM me for my phone # & I will call if it is easier. Thanks guys! Great site!

Glenn

I just put one of those little spectra dial regulators in between the carb and the pump and dialed it to 3.5

I have another thread up right now that my truck failed emissions after the conversion it's reading way high on the CO and HC. I wasn't running a regulator for a while so it's likely it was dumping excess gas in there. I'm only 6 months away from not needing the emissions check, but it's still a pain in the ass for right now.

Also I had a couple plugs fouled which you can see the fun in my "Red Hot Cat" thread.

As far as the hose hookup goes, since I'm running the regulator all I did was hook up the fuel out line to the carb and left the other two in their original positions. No problem with gas tank pressure of course going that way.

One thing I did notice that going lower than 3.5psi you lose power quickly. At 2.5 it topped out at about 60 on the highway and the temp was running right at the mid mark. Normally my temp runs at the first mark. At 3.0 it did a little beter but would start coughing around 70mph.

So I'd say being a bit above wouldn't hurt, especially if you don't have to pass emissions, but don't take it below 3.5