Reg Return vs. Crossover

[Mdub707]

My only problem is I can't use your RR without some serious modifications, due to the vegistroke system. The only saving grace is my WVO pump can keep 75psi of oil fed to my injectors no problem.

 

[sly1types]

do the modified banjos really help? I have the blue springs upgrade and its 70psi at idle but I can get it down to 45-46psi on a hard pull.

Do I just need more fuel and/or RR?

 

[Mwilbur516]

Somethings up if you're dropping 25lbs. on a pull. I sit at 70psi at idle and even on my hottest tune on a WOT run I don't drop below 55psi. You have clean fuel filters?

 

[SIX_OHH]

Somethings up if you're dropping 25lbs. on a pull. I sit at 70psi at idle and even on my hottest tune on a WOT run I don't drop below 55psi. You have clean fuel filters?

You have a stock setup?

 

[Pizza pig]

do the modified banjos really help? I have the blue springs upgrade and its 70psi at idle but I can get it down to 45-46psi on a hard pull.

Do I just need more fuel and/or RR?

seems like your fuel pump is weak to me, holding 70 psi at idle with a failing pump isnt all that hard if theres no load

 

[Mdub707]

I have a brand new pump in mine and drop more than 25lbs according to my EV2... no one can answer that one. Updated FPR, brand new old style fuel filters without the o-ring, reading pressure behind the heads. Idle it's about 67psi, cruising down the road about 57psi and WOT it drops to 25psi or less.

 

[Pizza pig]

I have a brand new pump in mine and drop more than 25lbs according to my EV2... no one can answer that one. Updated FPR, brand new old style fuel filters without the o-ring, reading pressure behind the heads. Idle it's about 67psi, cruising down the road about 57psi and WOT it drops to 25psi or less.

Yeah I guess some of these pumps are good and some just arent as good it seems. My original pump with 170k on it is still putting 70 psi at idle and holds 55+ at WOT, ive seen new pumps doing just what yours is doing. Ill be adding a sump to my fuel system when I do a RR and Im going to see that holds up to bigger injectors without adding a fass or airdog

 

[SIX_OHH]

Just depends on how big of injectors your talking about/

 

[Pizza pig]

im going to try and feed either 175's or 190's with a 03 turbo and batmowheel first

 

[Mdub707]

Yeah I guess some of these pumps are good and some just arent as good it seems. My original pump with 170k on it is still putting 70 psi at idle and holds 55+ at WOT, ive seen new pumps doing just what yours is doing. Ill be adding a sump to my fuel system when I do a RR and Im going to see that holds up to bigger injectors without adding a fass or airdog

My buddy is having the exact same issue except he's using an AD2 set at 65psi, with fuel lines run straight to the heads, cutting out the fuel bowl. Where are you reading your pressure? Myself and my buddy are reading behind the heads on what is essentially a x-over line. When I get my truck back from the dealer, I'm going to try reading pressure up at the bowl, and note the difference.

Just depends on how big of injectors your talking about/

I'm running stock injectors on mine FWIW.

 

[Pizza pig]

im reading off the fuel bowl, could be the difference right there.

 

[SIX_OHH]

im going to try and feed either 175's or 190's with a 03 turbo and batmowheel first

You will most likly be fine on 175s and slightly starve 190's. its just alot of fn fuel.

My buddy is having the exact same issue except he's using an AD2 set at 65psi, with fuel lines run straight to the heads, cutting out the fuel bowl. Where are you reading your pressure? Myself and my buddy are reading behind the heads on what is essentially a x-over line. When I get my truck back from the dealer, I'm going to try reading pressure up at the bowl, and note the difference.



I'm running stock injectors on mine FWIW.

Just think about how the fuel is moving and being sucked up. ponder that for a bit and i think you can understand why your pressure drops so dramatically. What fuel line does v stroke use? Stock or bigger or same?

im reading off the fuel bowl, could be the difference right there.

Alot of difference. Constant pressure is being applied but dramatically drained later on.

 

[Pizza pig]

You will most likly be fine on 175s and slightly starve 190's. its just alot of fn fuel.



Just think about how the fuel is moving and being sucked up. ponder that for a bit and i think you can understand why your pressure drops so dramatically. What fuel line does v stroke use? Stock or bigger or same?




Alot of difference. Constant pressure is being applied but dramatically drained later on.

Yes well, fuel will be limited with tuning

 

[SIX_OHH]

So, seriously asking, I may sound like a smartass. This is not my goal! Forgive my wording.

If you want fuel to be limited by tuning why get more injector than you can handle?

 

[Pizza pig]

because with 190's Ill be upgrading to compounds or bullseye 62mm non vgt with batmowheel

not keeping the stock turbo, but I will run it until im ready to go big

 

[SIX_OHH]

lol ok then.

 

[Mdub707]

Just think about how the fuel is moving and being sucked up. ponder that for a bit and i think you can understand why your pressure drops so dramatically. What fuel line does v stroke use? Stock or bigger or same?

Alot of difference. Constant pressure is being applied but dramatically drained later on.

I understand how the fuel system works, quite well. I said it previously, there is a difference in static pressure and dynamic pressure, I just find it extremely hard to believe it will hold 65psi at the fuel bowl, but fluctuate 40psi behind the heads. It's still a closed loop system with the regulator bleeding pressure off BEFORE either place I would be reading pressure, in theory it shouldn't matter, however we all know it will, but to what extent? If a pump can supply a given pressure in a regulated system and flow the correct volume to feed the injectors, then pressure should not be fluctuating this much.

Again, it boils down to dynmaic vs static pressure. Most guys are thinking statically.

Pizzapig, what fuel pressure gauge are you using?

 

[Mwilbur516]

You have a stock setup?

My fuel system is stock besides the 6.4l banjos and the updated blue spring.I'm also reading at the bowl, but have checked my pressure a couple times with a mechanical gauge so I know my electric gauge in the cab is right. I have no clue what the pressure behind the heads would be. I do know a guy around here who sits at 65psi at idle and drops to 40psi on a WOT run. He's reading at the bowl as well.

 

[colonyofdrones]

Lots of good information here. I've been wanting to upgrade my fuel system lately as I've been experiencing some drops in fuel pressure during wot runs on hotter tunes. I've already got the itp rr kit w/ stock sticks and thats where I'm reading the pressure from with an autometer gauge. Most of the time it will hold at around 60psi but if I flat foot it I'll be seeing 40-45 real quick. Bummer.

It's hard to know what to put in the truck fuel system wise with all the issues I'm seeing people have with both of the more popular kits out there. The discussion here has made me reconsider trying to just build my own system. Could be fun...

 

[BlueWaffle]

Lots of good information here. I've been wanting to upgrade my fuel system lately as I've been experiencing some drops in fuel pressure during wot runs on hotter tunes. I've already got the itp rr kit w/ stock sticks and thats where I'm reading the pressure from with an autometer gauge. Most of the time it will hold at around 60psi but if I flat foot it I'll be seeing 40-45 real quick. Bummer.

It's hard to know what to put in the truck fuel system wise with all the issues I'm seeing people have with both of the more popular kits out there. The discussion here has made me reconsider trying to just build my own system. Could be fun...

do you have an aftermarket lift pump?