mattausten23 Posted August 8, 2013 Share Posted August 8, 2013 Whats up everyone. I just installed triple Webers onto my L28 and now I need to get this thing running This is going to be a huge task for me since it is my first time doing any real engine work, but I have some help from friends. My question is about the fuel pump. I purchased a fuel pump for a carbureted RX7 since I heard they are quiet and work well. I was wondering how to run the fuel line? I already have some rubber fuel line to run from the tank to the carb and already deleted the old mechanical pump. Do I run the line from the fuel supply inlet on the tank to the fuel pump then to the engine? What do I do with the fuel return inlet on the tank? Also am I able to run the rubber fuel line as I planned? Also how will I wire it up? Sorry for the rookie questions but I can't find any clear explanation of this on the web. Quote Link to comment Share on other sites More sharing options...
Domzs Posted August 8, 2013 Share Posted August 8, 2013 Need to know what year model . Quote Link to comment Share on other sites More sharing options...
seattlejester Posted August 8, 2013 Share Posted August 8, 2013 It is not advisable to run a rubber line front to back. Some strict race events will turn you away if you have more than a foot of rubber line in your system, and in general it is not very safe or smart. Buy some steel or aluminum hardline and run it most of the way and use rubber lines for connections. The bends in the trans tunnel is not very hard, the area above the axles can give you some trouble, but as long as you test fit and bend you should be fine. Most pumps are pushers, mounting it as close to the tank is ideal. Some will come with warnings stating not to have the pump push more than 9 inches in elevation or somewhat: Fuel tank - Fuel Pump -------------------------------------- Carb - Fuel Pressure Regulator ------------------------------------------ Fuel tank. The longer sections should be hardline if possible. I did not have to run an FPR on my carbs, but it will be one of the first things people ask about if you have problems, (what is your fuel pressure set at). Quote Link to comment Share on other sites More sharing options...
Tony D Posted August 9, 2013 Share Posted August 9, 2013 What's wrong with the line already in the car? Most guys put the RX7 pump where the stock electric pump went and use the stock line, plenty big enough. Quote Link to comment Share on other sites More sharing options...
mattausten23 Posted August 9, 2013 Author Share Posted August 9, 2013 Sorry guys my Z is a 1972 with a l28 swap. It had a mechanical pump on the block, I dont think the Rx7 pump would work there. I guess I can use the stock steel line but what would I do with the fuel return line? The stock mechanical pump had an inlet for the return line but the rx7 pump doesnt. So there are a pair of steel lines running to the engine bay, one being return and the other is supply. Quote Link to comment Share on other sites More sharing options...
mattausten23 Posted August 12, 2013 Author Share Posted August 12, 2013 Anyone? Should I just delete the fuel return line or is there a way to run it with the Webers? Quote Link to comment Share on other sites More sharing options...
Tony D Posted August 12, 2013 Share Posted August 12, 2013 Please read any f the numerous posts in the fuel delivery forum for schematic layout of your triples setup. Jeez! C'mon!! Quote Link to comment Share on other sites More sharing options...
Sideways Posted August 12, 2013 Share Posted August 12, 2013 (edited) Mount the fuel pump in a suitable location close to the fuel tank.Connect the stock fuel tank pick up to the "in" side on the fuel pump.Connect the "out" side of the fuel pump to the factory hardlineIn the engine bay connect the engine bay side of the fuel line to your fuel rail, and contemplate using a fuel filter between the two points (strongly recommended)Connect the return side of your fuel rail to a fuel pressure regulator if you wish to regulate fuel pressure in the bowls.Run a fuel return line. I was lazy with mine since its a low pressure line, and just ran a rubber line along the transmission tunnel that I took extra precautions to insulate it. I attached a connector to my factory fuel sending unit for simplicities sake. But by all means the "proper" method is to use as much hardline as you can.Bobs your fathers brother.For wiring? So many ways under the sun to do this. The EASIEST way? Ground the fuel pump. Run a wire from the battery to a switch inside your cabin- and run the switch to the fuel pump. Need fuel? Turn on the switch. Dont need fuel? Turn off the switch.The slightly less easy way? Ground the fuel pump. Run a relay that is switched on when the key is in the running and starting positions from the ignition switch. Connect the battery to the relay. Connect the relay to the fuel pump. Bobs your fathers brother. Edited August 12, 2013 by Sideways Quote Link to comment Share on other sites More sharing options...
mattausten23 Posted August 12, 2013 Author Share Posted August 12, 2013 Thanks Sideways! I just couldnt find any info on the fuel return. Quote Link to comment Share on other sites More sharing options...
Sideways Posted August 13, 2013 Share Posted August 13, 2013 Ive relatively little experience with Zs outside of my own Z sadly. Looking around some people claim to have factory return lines for their early Z models it seems. Im not sure what the story is on this, factory/dealer option maybe? Id love some insightful input from someone more knowledgeable than myself. Mine didnt have one for whatever the reason may be- So I had to make my own. The line doesnt need to be big, since it SHOULD flow freely into the gas tank and there shouldnt be any "pressure" build up in the line.Good luck! Quote Link to comment Share on other sites More sharing options...
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