Fuel Injectors And Fuel Pump?

[hossram64]

Im putting a smaller pulley on my procharger to bring it to 12psi and also putting a meth injection kit. What injectors should I get right now I have delphi 44lb injectors. Also right now running stock fuel pump I want to do a inline fuel pump what pump should I get? Thanks for any suggestions. Also with injectors besides the motron 60lb injectors is there anything else that would work for are trucks. Also am I looking for High imp. or Low imp.? Thanks

[misterp]

Assuming you are running an OEM-plumbed fuel system with factory return...

 

Injectors - you need high-impedance injectors, at the level of boost you are planning I would recommend 60-pounders, you have a couple options:

1. Use Seimens 60# injectors - these are physically longer and use the older EV1-style plug, so you have to first cut off all the injector plugs from your engine harness and solder on eight new EV1 connectors plus go to the hardware store and get 4 3/8" spacers & 4 longer bolts to lift the fuel rails high enough to clear;
   
2. Use Multec injectors that have been re-drilled to flow 60+ pounds, there are two vendors that I know of doing this - Jaime Verduzco (SRT10KLLR here on the forum, or www.ElColasMotorSports.com), and FiveOMotorsports on eBay; the advantage to this option is that the injectors are plug-and-play (same size and electrical connector) but they are more expensive.
   

Another good idea at this level is replacing the fuel pressure regulator with a boost-referenced one, that way the fuel pressure rises as the boost does but to do this will require a rework or replacement of the fuel rails and a bunch more plumbing & expense.

 

Fuel Pump - at that level of boost I don't think a single pump solution will work; nor a 'pusher pump' in series. You have a couple options IMO:

1. You can upgrade the in-tank pump to a Walbro 255, and that alone might support the motor's needs but to be honest with you I'm not sure if that will do it or not;
   
2. You can install two Walbro 255 pumps in the stock fuel tank pump bucket (teed together) and wire the second pump to kick on with a pressure switch on the intake manifold as the motor goes into boost; continue to use the factory 3/8" & 5/16" plumbing to/from the fuel rails and this has been proven to support about 750-800 wheel HP;
   
3. Do exact in-tank setup like the above option, but upsize the plumbing to 1/2" (-8 AN) pressure and reuse the factory 3/8" as a return - good for about 1100-1200 wheel HP;
   
4. You can go to an auxilary surge tank setup like MIGNIGHTRIDR is installing (similar to what professional road racers use) - install a Walbro 255 pump in-tank, and a 1-2 gallon fuel cell underhood, then plumb the Walbro to fill the underhood fuel cell, and last install a *massive* fuel pump (Aeromotive 1000 or similar) with 1/2" (-8 AN) plumbing to the fuel rails - I have no idea off the top of my head how much HP this solution will feed, but it's a freakish amount and guys that run it point out that if there is a pump failure in either tank the motor will just *quit* rather than operate lean;
   
5. There are a few vendors that sell ready-to-go systems like the designs mentioned above, the first that comes to mind is Lonnie's Performance and even though the price tag is $$$ it's actually a fairly priced kit IMO.
   

Any way you go, upsize the wiring to the pumps, the GM harness is barely adequate IMO. And remember to install adequate fuel filtration.

 

If you want the horses, you gotta feed them the hay!

 

Mr. P.

Edited July 1, 2009 by Mr. P. (see edit history)

[sswhipple8]

I just recently installed some siemiens deka 60#s on my truck . I got a hold of fuelinjectorconnection.com and had them make me pigtails for our Delphi to ev1 style. It was around 100 bucks for all 8 so it wasn't to bad it's better than cutting in splicing . Mine was a little more difficult to get the fuel rail to clear my whipple so , looking at ur mods u shouldn't have that issue