[JANNETTYRACING]

Originally Posted by ramairroughneck

I got a reply from XDI. After seeing his response I believe the different pumps could be used together. He makes it sound as if the XFP 3200 takes a LT4 pump up 3200 pounds of pressure on the injectors. I had it in my mind that the two ran at different pressures but now I think the additional XDIs pump is bringing an LT4 pump up to either 3200psi or 3600psi depending on which XDI pump is used. It sounds like they have quality injectors.

Here’s his response

Thanks for your message !
The idea of the XFP3200 is to match it to a given LT4 pump.
And the 2nd thought behind it, is that none of the available aftermarket injectors can handle more than 3200psi anyway.
I would go as far as saying, our XDI injectors are the only ones that can handle 3000psi at all, but I am biased :-)
The LPE system for example is limited to 2175psi.
The FIC injectors start misfiring at 2800psi.

The XFP is the first pump solution that has enough capacity to even maintain 3000psi at power levels over 1000whp.
Our 30-over injectors are the first to run solid at 3200psi.
Our 65-over injectors are still solid at 2800psi desired, that is having overshoots up to 3000psi w/o any injector misfire.

I stand corrected you can run and LT4 pump on the XDI pulley but must run LT1 Pressures if running an LT1 pump in the system.

Ted.

[Uwe@XDI]

Originally Posted by JANNETTYRACING

I stand corrected you can run and LT4 pump on the XDI pulley but must run LT1 Pressures if running an LT1 pump in the system.

Ted.

Ted,
we have managed to modify a given LT1 pump to hold up to 3500psi pressure.
This modification is patent pending.
That is what the XFP3200 is, the XFP bottom end, cam housing, brackets, pulley etc, but a modified LT1 pump on top instead a modified LT4 pump.
The old convention, "if there is an LT1 pump in the system, never run more than 2800psi" is still valid, but now refers to a stock-LT1 pump.
There will be more information coming soon.

[Uwe@XDI]

Originally Posted by ramairroughneck

I realize that it is an LT1 pump. But if you have a 38% driven LT4 pump, if it would work with the new, cheaper XDI lt1 pump, it should supply all you would ever need. The fact that they operate at different pressure concerns me. I figure the switch back to an LT1 would be required.

just to make sure, you cannot just take any LT1 pump or LT4 pump and put it on the XFP. We modify both to fit, spring and spring retainer.
And the new XFP3200 comes with a highly modified LT1 pump. This one can handle spikes of up to 3500psi and was developed to work together with an LT4 pump. As a rule of thumb for running multiple HPFPs in the same system, you always need to keep the desired pressure at the level of the weakest HPFP.
stock LT1: 2800psi (3200psi is too much !!)
stock LT4: 3600psi
XDI-LT1: 3200psi

Next limiting factor is injectors, these start to misfire at higher pressures:
stock LT1: never tried, lol
stock LT4: 3500psi (not measured myself, feedback from tuners)
FIC+30: 2800psi, every spike to 3000psi makes them misfire
LPE: 2200psi (not tried myself, feedback from tuners)
XDI+30: 3200psi
XDI+65: 3000psi

[laynlo15]

Great information, thanks for posting.

[D3adch1ld]

Originally Posted by Uwe@XDI

just to make sure, you cannot just take any LT1 pump or LT4 pump and put it on the XFP. We modify both to fit, spring and spring retainer.
And the new XFP3600 comes with a highly modified LT1 pump. This one can handle spikes of up to 3500psi and was developed to work together with an LT4 pump. As a rule of thumb for running multiple HPFPs in the same system, you always need to keep the desired pressure at the level of the weakest HPFP.
stock LT1: 2800psi (3200psi is too much !!)
stock LT4: 3600psi
XDI-LT1: 3200psi

Next limiting factor is injectors, these start to misfire at higher pressures:
stock LT1: never tried, lol
stock LT4: 3500psi (not measured myself, feedback from tuners)
FIC+30: 2800psi, every spike to 3000psi makes them misfire
LPE: 2200psi (not tried myself, feedback from tuners)
XDI+30: 3200psi
XDI+65: 3000psi

Much appreciated information. I am soon looking to get a 3600 system for my LT4. From what Ive gathered from Jannetty's statement and yourself, the xdi controller splits the signal to between both pumps to achieve theb commanded fuel pressure. Are there any changes needed on hpt to accomplish this?

For reference, my car is commanding 2900 at the rails (LT4 hpfp and Injectors), OE fuel lobe, low pressure is steady at 80psi (LT4 in tank and DSX Aux).