I just bought a Buschur Racing double pumper fuel system and I was wondering should I wire it using two relays and a vacuum switch for the second pump like the image below or just one relay for the first pump and just the vacuum switch for the second pump?

 

Use 2 relays, U can use the stock power and ground to turn on the first pumps relay. Then use the hobbs switch to turn on the second relay. Run one fused power wire y'd to both relays.

 

So if I'm correct I run it like the drawing before right?

 

Correct! Are you using a stock ECU or aftermarket EMS?

 

That diagram looks correct.

 

This is going to a DSM and using ECMLink.

 

Just a suggestion, but maybe think about wiring both pumps to run at the same time using two relays and stock power and ground as trigger. I just dont like the idea of the second pump being controlled with a pressure switch. also easier to tune. just somthing to think about.

 

I thought about that, but you wouldn't need two relay for that and it also creates several problem for me.

Turning the second pump on when not needed will possible create fuel pressure overruning at idle, it also creates wear and tear to both pumps when one can is only needed, and the main thing is it reduces current draw from the electrical system too. Which does a lot for me because I'm running a relocated Hawker drycell battery and the car starts acting up at idle when too much power to needed.

 

look for a thread tittled Full Blown Dual Pump System - Things You Should Know by Ted B (evom guru). Theres good info. he did his dual pump setup with both pumps runing. The issue of over run at idle is easily fixed. There is a T shaped siphon in the tank that if you drill out the oriface with a 9/64 drill bit usually solves the problem and should return normal fpr at ide...thats if you still wanna consider it

 

Buschur setup it up with a y fitting and gave a vacuum switch so I'll just stick with the trigger for the second pump and as I stated before my electrical system cannot handle both pump at the same time at start-up. I even have trouble turning on my head lights at the same time at start-up.