I have a walbro 400 install in my evo 8,but i was hooking it thru my stock electric line(nagative and positive that plugs into my fuel canister). Many people say that i need to put a relay so i can get the proper voltage for my fuel pump.
Yesterday, i bought a relay from a autoparts store and when home n hook it up. I cut the large white wire that plugs into the top of the fuel canister. Then run one side to the #86 on the relay and the other to the #87 on the relay to the fuel pump power wired. I plug #30 to the positive side of my battery and #85 to the negative of the battery. When i was done with everything. I start the car and i notice my fuel pressure gauge go all the way pass 100psi. Then after a few minute, i see the fuel pressure went down all the way to zero the the engine turn off. Couldnt turn it back on because there was no more fuel pressure. Check the relay and smell a burn smell. I disonnect everything and put the white wired back as stock and the engine is back to normal. Normal driving might be good on the stock wire setup but im afraid at high boost i might not have proper voltage to run the walbro fuel pump.

So can someone help me to see what i did wrong?

 

Nobody help???!!

 

http://www.enginebasics.com/Advanced...p%20relay.html

Does this help? Also are you running a fuel pressure regulator?