So, I’m nearly done upgrade my fuel system, I’ve just installed a Walbro 485 fuel pump, DeatschWerks fuel pump hardwire install kit, DeatschWerks 1000cc fuel injectors, a CJM stage 1 return fuel system, GM/Continental flex fuel sensor, and Zeitronix ethanol content analyzer.

I’m just finishing up wiring in the fuel pump hardwire kit and wiring the flex fuel sensor to my ProEFI 48; but before I get the car on the road I just wanted to see if there’s anything else I need to do?

I’ve started the car to check for leaks, found two so far, I just made sure I had Teflon tape on the fittings and tightened them.

Also, I’m going to adjust the fuel pressure regulator to sit at 59 psi (when I started the car it was sitting at 69-71 psi at idle), I’ll also leave the vacuum hose disconnected till I take it to the dyno.

With regards to my current tune, I’m planning on just adjusting my tune to reflect the new 1000cc fuel injectors (upgraded from 600cc DW’s). The 485 fuel pump’s replacing my old 255 (I don’t think I’ll be able to make any adjustments for the new pump?).

Anything else you guys could think of in order to get my car on the road and ready to rack up 200-300 miles on before I hit the dyno?

Thanks!

 

I think you should hurry up and tune it. And then take me for a ride in it...

 

Remember to raise the pressure back up after you reconnect the hoze... if I were you i'd connect it now and put the pressure back where it should be.

 

Maybe I am missing something but I don't see any fittings in your setup that would require teflon tape? Neither AN fittings nor o-ring face seal (ORFS) fittings require tape - in fact you can create leaks if you accidentally get tape on the flare portion of an AN fitting. You can, however, apply some motor oil to the threads to reduce friction when tightening the flare nuts - this is known as "wet torquing". You only really need to tape NPT (tapered) pipe threads. BUT, if it's all done and there are no leaks then I would leave it alone at this point.

I you already knew all of that and I am being a weeny then I apologize.

Also I don't see the reason why you would leave the vacuum line disconnected from the regulator? I would leave it connected always, except when setting the base pressure. Otherwise it just increases your chances of running dangerously lean if you accidentally find yourself in boost.

 

Also may I ask what size drill bit you used on the swirl jet with that Walbro 485 pump? I had to increase the size of the hole (well above what CJM recommended for a Walbro 255) when I went to an Aeromotive 340 because I couldn't get the fuel pressure low enough even with the regulator backed off all the way. I am sure I posted about it some time ago, I would have to go digging to find the size I used.

 

Also FWIW the regulator can only raise the pressure, it cannot lower it. So in order for the regulator to do its job (which is to keep the pressure delta between manifold and fuel rail constant) then your "minimum" fuel pressure should be at least a few psi below the minimum "regulated" presssure that you would expect to see at high vacuum (idle) with the vacuum line connected. The problem I ran into was that the swirl jet was effectively raising my "minimum" fuel pressure and therefore interfering with the regulator being able to do its job.

For example, if you want you base (vac hose disconnected) fuel pressure to be 51 psi (aka 3.5 bar, pretty standard) and your car idles at 25 in-hg vacuum (-12.3 psi) then you should see 38.7 psi with the vacuum line reconnected. If the pressure drops less than expected (or not at all) when the line is reconnected, then something else is acting as a restriction and keeping the pressure artificially high. While it is possible to tune around this issue ("bake it in to the calibration", so to speak) I wouldn't recommend it because you will find that the "minimum" pressure, if left to be determined by a restriction such as the swirl jet, will change with temperature and your calibration will be off depending on the temp of your fuel. It's best to let the regulator dictate pressure in all situations.

 

Found it:

https://my350z.com/forum/forced-indu...swirl-jet.html