Just so you know theres multiple forms of efficiency when involving a turbo, not just thermal dynamics. When I said said 300 hp efficiency my knowledge of that reference was lacking, but that reference talks about the potential horse power of a car when using a certain turbo. I originally thought it referenced the horsepower that the turbo could produce given the proper airflow, not including the actual engine potential.

 

its cool marbro we knew what you were talking about. what you said was right that turbo would be easily 72 or 73 percent efficient at 300 hp.

 

I gotcha.

For those who are lost, like I was at first, power potential can be estimated by lbs/min @ x boost pressure, with correct mapping turbos have efficiencies usually around 70% max on older turbos, the x-axis of the map tell the flow numbers, while the y-axis tells the boost preesure in BAR. The graphed area of the map shows the efficiency of the turbo at those two points. The point of mapping is to make sure that the engine will not choke on the air being supplied or burn up, because the turbo is overheating the air and everything else around it. there's more to it, but that's a decent summary.

E.g.

 

I gotcha.

For those who are lost, like I was at first, power potential can be estimated by lbs/min @ x boost pressure, with correct mapping turbos have efficiencies usually around 70% max on older turbos, the x-axis of the map tell the flow numbers, while the y-axis tells the boost preesure in BAR. The graphed area of the map shows the efficiency of the turbo at those two points. The point of mapping is to make sure that the engine will not choke on the air being supplied or burn up, because the turbo is overheating the air and everything else around it. there's more to it, but that's a decent summary.

E.g.

http://img.photobucket.com/albums/v3...rcompress2.gif

 

Alright, I installed the fuel pump today. I did have to drop the tank (which sucked) since I only had an access panel that went to the fuel sender. Drop the tank and install the walbro. I had to reuse the stock pick-up filter since the walbro one seemed like it didn't extend as far and wouldn't fit with the stock pump bracket. I also used the stock electric plug.

Reasemble everything and the car doesn't start. You can hear the new pump when you turn the key and stuff. No fuel comes out of the fuel pump outlet directly from the tank. I'm thinking that the polarity of the stock wiring and the pump are reversed, something I should have checked when I had the darn thing out in front of me. Any other ideas? I could swear that I hooked all lines, etc. back in place.

 

yea i think you have something hooked up wrong....drop that tank again...there is an offf chance that you just dont have enough fuel in the tank to support that high flowing pump...but a full tank is much harder to deal with..

 

mbo there is a good chance that you just dont have enough fuel in the tank....if you SURE that you hooked everything up right and you can hear the pump doing its thing..then fill that tank up some more.

 

I'm pretty sure I hooked up everything right. the only thing I'm not sure of is the connector to the pump. The stock plug worked with the walbro, so i just plugged it in, not checking the polarity. I'm wondering if maybe the stock plug and the walbro polarity are opposite. I can hear the pump come on, but nothing comes out. There is just under a quarter of a tank of gas in the tank, is that enough?? thanks man...

 

Okay I could be a moron at this point but whatever, if the polarity was reversed and you removed the gas cap and the pump was working wouldn't it be blowing air into the tank when you took off the line running to it? So in turn you should be able to hear bubbles in the gas tank if that were your issue correct? Just a thought, could be talking out my **** but brainstorming never hurt anyone except my brain

 

I think that makes sense. Unless the pump can't manipulate air, I would think that would be a sure fire way to check without removing the tank again. It sounded like the pump wasn't really making bubble sounds though, just kinda humming and the hum echoing in the tank. hmm...