phantaz Posted November 11, 2010 Share Posted November 11, 2010 Hello all, Ive come across a set of Triple 40 webbers and since i having issues with my stock FI system (30years old) im thinking of putting the trips on. Ive got most of it figured out including a nice fuel regulator to drop the pressure down but my question regards the actual stock 77 fuel pump. 1. does it pump fuel when the key is on or only once the car is started and running? my Dad and I had ariginally thought it pumps when the key was on to keep the pressure up but now im not sure. He has a triple webber set up and has 2 remote fuel pumps that use switches he installed but can we just run a hot wire to the stock pump to turn on with the key or to a switch? kinda rambled that last bit but thanks for any suggestions or comments in advance. Quote Link to comment Share on other sites More sharing options...
BLOZ UP Posted November 11, 2010 Share Posted November 11, 2010 Why don't you want to troubleshoot the issues you are having with the stock EFI? Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted November 11, 2010 Share Posted November 11, 2010 (edited) The EFI pump turns on for a burst of pressure when the key is first put in the run position. Â It then shuts off and waits for the engine to crank and fire up, upon which the pump will run continuously maintaining EFI pressure of somewhere North of 30psig.... Â If the engine stalls, so does the pump, via a switch in the AFM, regardless of the key in the run position. For Webers you need 3psi of fuel. Â You need a different fuel supply system. ie. pump, regulator, return line use (optional). Its always a good idea to have the pump shut off if the car is hit or rolls over. Â They make switches for that. Â Search "intertia switch" and consider using it when you wire a fuel pump to any switch or relay. Edited November 11, 2010 by cygnusx1 Quote Link to comment Share on other sites More sharing options...
phantaz Posted November 12, 2010 Author Share Posted November 12, 2010 Why don't you want to troubleshoot the issues you are having with the stock EFI? Mostly because its become a money pit.. every time i fix something on the system something else is an issue. Ive thought about Megasquirt and thats still an option but a free set of working triples are hard to pass up. Quote Link to comment Share on other sites More sharing options...
phantaz Posted November 12, 2010 Author Share Posted November 12, 2010 (edited) The EFI pump turns on for a burst of pressure when the key is first put in the run position. Â It then shuts off and waits for the engine to crank and fire up, upon which the pump will run continuously maintaining EFI pressure of somewhere North of 30psig.... Â If the engine stalls, so does the pump, via a switch in the AFM, regardless of the key in the run position. For Webers you need 3psi of fuel. Â You need a different fuel supply system. ie. pump, regulator, return line use (optional). Its always a good idea to have the pump shut off if the car is hit or rolls over. Â They make switches for that. Â Search "intertia switch" and consider using it when you wire a fuel pump to any switch or relay. These are the 45's not the 40's like i originally thought. the carb set comes with 2 fuel pumps, pressure gauge, fuel pressure regulator, fuel line T-fitting before the reg ( i believe to send the back pressure fuel off the T to the return line to the fuel tank)fuel block with 3 fuel outlets and fuel lines to the webers, all six filters and all the linkage. the Inertia switch is a good idea i hadnt thought about. Thanks for the responses. =0) Edited November 12, 2010 by phantaz Quote Link to comment Share on other sites More sharing options...
phantaz Posted November 12, 2010 Author Share Posted November 12, 2010 i had read somewhere else in here that you can use the stock fuel pump but if it wont "feed" the bowls before start up im not sure how that will work. sounds like a good way to run down your battery. the fuel pressure regulator would i assume keep fuel in the carb lines but if the car set for a week or two that fuel would evaporate im assuming. Quote Link to comment Share on other sites More sharing options...
mario_82_ZXT Posted November 12, 2010 Share Posted November 12, 2010 77s could be an oddball. Early 77s had the pump switch in the AFM like stated above, but later ones will have it on the oil pressure switch. If you oil pressure switch has a 2 prong connector it will be there. If it's a bullet connecter it's in the AFM. You can also double check with the AFM. If the AFM has a 7 pin connecter it has the angel switch. Otherwise it's a 5 pin (if I remember correctly). Tripples will be fun for sure, but the stock EFI is really simple. More so then tripples (IMHO). Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted November 12, 2010 Share Posted November 12, 2010 (edited) I liked the L-Jet very much once I memorized the FSM.  It's really a simple system.  I like the Webers over the L-Jet simply because of the multiple throttle plates, breathing potential, the mystique, and of course, the sound. BTW if you decide to go with Megasquirt or stay L-Jet, I'll give you DOUBLE what you paid for that set of Webers.  You said you got them for free right? Edited November 12, 2010 by cygnusx1 Quote Link to comment Share on other sites More sharing options...
phantaz Posted November 12, 2010 Author Share Posted November 12, 2010 I liked the L-Jet very much once I memorized the FSM.  It's really a simple system.  I like the Webers over the L-Jet simply because of the multiple throttle plates, breathing potential, the mystique, and of course, the sound. BTW if you decide to go with Megasquirt or stay L-Jet, I'll give you DOUBLE what you paid for that set of Webers.  You said you got them for free right? no problem.... shipping will be around $1000.00 though.. cough cough. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted November 12, 2010 Share Posted November 12, 2010 no problem.... shipping will be around $1000.00 though..  cough cough. Local pick up! Quote Link to comment Share on other sites More sharing options...
Tony D Posted November 12, 2010 Share Posted November 12, 2010 The only requirement on a 77 would be some fuel pump relay jumpers (through that inertial switch as mentioned) and a different regulator. There are more out there on the market, they sell them in Summitt, Jegs, etc... The stock EFI pump is what supported me on my blowthrough turbo at well over 300HP, for N/A Webers it's a cakewalk for that pump...and it's QUIET! Worst case, you hook up to the fuel pump pigtail under the carpet behind the passenger's seat with some bullet connectors and run your relays and switch under the dash... Quote Link to comment Share on other sites More sharing options...
phantaz Posted November 15, 2010 Author Share Posted November 15, 2010 The only requirement on a 77 would be some fuel pump relay jumpers (through that inertial switch as mentioned) and a different regulator. There are more out there on the market, they sell them in Summitt, Jegs, etc... The stock EFI pump is what supported me on my blowthrough turbo at well over 300HP, for N/A Webers it's a cakewalk for that pump...and it's QUIET! Worst case, you hook up to the fuel pump pigtail under the carpet behind the passenger's seat with some bullet connectors and run your relays and switch under the dash... Fuel pump relay jumpers... we were going with a hot wire to the pigtail to a remote on off switch i already have on the dash so im assuming that what you mean.. =) 5 lb regulator is going infront of the fuel block so im hoping that should do it... Sounds like what we had planned already but was just looking for more info.. thanks for the responses.. Quote Link to comment Share on other sites More sharing options...
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