LS Swap 70c10 Need help

[The Chainsaw]

No problem! I honestly would feel better with it being gravity fed, but decided to try this out since the pump is cheapish to replace.

My chevelle has two of them mounted to where it has to pull fuel almost straight up about 8 inches. The second one comes on at 10ish pounds of boost. Haven't had any problems yet.

[Project_70']

also another quick question, on the return side of my system is it pressurized? how would i run it with the stock tank? im running rubber efi hose from my sending unit to my pump then from the pump will be stainless braided line to the feed on the rail and for the return either regular efi hose or braided if it has pressure on that side, any replies would be great thanks.

[ls1nova71]

Originally Posted by Project_70'

also another quick question, on the return side of my system is it pressurized? how would i run it with the stock tank? im running rubber efi hose from my sending unit to my pump then from the pump will be stainless braided line to the feed on the rail and for the return either regular efi hose or braided if it has pressure on that side, any replies would be great thanks.

The return side will have some pressure on it or else the fuel will just be sitting there. The question is how much, and that's determined by how much fuel is being used at any given time, but typically it will b e a very low pressure compared to the feed line.

As for the pump sucking fuel, it can be hit or miss. There's a guy on here right now that I think is suffering from not enough fuel pressure at times, likely due to the pump trying to suck the fuel up the stock sender and then to the pump. When the pump begins to get weak, or doesn't have enough power going to it you may see a lean condition and could get a check engine light. electric fuel pumps are designed to push fuel more effectively than pulling it. I've done it both ways, used the stock sender with a pump mounted under the cab, and a gravity feed to an under cab pump. The gravity feed works much better and I have never had it starve for fuel even when the level gets low, something you will have to contend with, with a stock unbaffled tank. There are pics of both set ups in the build threads in my sig. The rusty green truck is the gravity fed one.

[Project_70']

Originally Posted by ls1nova71

The return side will have some pressure on it or else the fuel will just be sitting there. The question is how much, and that's determined by how much fuel is being used at any given time, but typically it will b e a very low pressure compared to the feed line.

As for the pump sucking fuel, it can be hit or miss. There's a guy on here right now that I think is suffering from not enough fuel pressure at times, likely due to the pump trying to suck the fuel up the stock sender and then to the pump. When the pump begins to get weak, or doesn't have enough power going to it you may see a lean condition and could get a check engine light. electric fuel pumps are designed to push fuel more effectively than pulling it. I've done it both ways, used the stock sender with a pump mounted under the cab, and a gravity feed to an under cab pump. The gravity feed works much better and I have never had it starve for fuel even when the level gets low, something you will have to contend with, with a stock unbaffled tank. There are pics of both set ups in the build threads in my sig. The rusty green truck is the gravity fed one.

okay i see you have a point lol and i see, well im going to try it out and see how it goes. i am needing help with my gauges if anyone can offer a little help on how they plumbed theirs(temp, oil press, ect..) ive got a fuel pressure gauge setup in the works but i am going to need others too. ive seen some here and there but want to see if anyone here has a good instructional thread or some direction for me, would be appreciated.

[ls1nova71]

Originally Posted by Project_70'

i am needing help with my gauges if anyone can offer a little help on how they plumbed theirs(temp, oil press, ect..) .

Depends on what gauges you are using. Stock or aftermarket?

[Project_70']

Originally Posted by ls1nova71

Depends on what gauges you are using. Stock or aftermarket?

Aftermarket. Using stock speedo. I'm using a Dakota digital vss adapter for the speedo

[Project_70']

Well I'm back on here again needing some help, so far everything else is good, 5.3 and turbo350 are in fuel system is good, exhaust, ect.. But now I'm trying to wire the thing up, and I'm wanting to be able to start the truck basically like original, slip the key in, turn and start it. But I'm having trouble wiring the starter up, and tracing wires from the ignition switch and things like that. I've done some research but still having problems. So far this is what I've got, I have the battery in, from positive post straight to starter, then the little lead on the starter is wired to the purple wire going to the ignition switch. And I know I may be a little air headed at the time and just overlooking something simple but I can't get it to start. I just want to be able to turn the starter over with the ignition switch and find which wires to splice into for the pcm. I'm using the stand alone conversion from lt1swap.com. does the starter have to be grounded with the other post coming off the other side or is it case grounded?

[Project_70']

Originally Posted by Project_70'

Well I'm back on here again needing some help, so far everything else is good, 5.3 and turbo350 are in fuel system is good, exhaust, ect.. But now I'm trying to wire the thing up, and I'm wanting to be able to start the truck basically like original, slip the key in, turn and start it. But I'm having trouble wiring the starter up, and tracing wires from the ignition switch and things like that. I've done some research but still having problems. So far this is what I've got, I have the battery in, from positive post straight to starter, then the little lead on the starter is wired to the purple wire going to the ignition switch. And I know I may be a little air headed at the time and just overlooking something simple but I can't get it to start. I just want to be able to turn the starter over with the ignition switch and find which wires to splice into for the pcm. I'm using the stand alone conversion from lt1swap.com. does the starter have to be grounded with the other post charness ff the other side or is it case grounded?

Okay so after tinkering with with it for awhile I've got power to the starter when I turn the switch to crank it but all it does is just tick like I've got a lose ground or bad connection I just put brand new terminals on and tightened everything down good. Maybe the battery I'm using is too weak. I also would like yo hear how you guys integrated the old wiring harness into the standalone harness