[Joshinator99]

Originally Posted by cjperformance

Im kinda concerned about running the car with the fuel pressure drop on low side. Especially with cooler weather coming, and more fuel needed at colder temps. Already riding the line.

I am looking at lt4 fueling, but wondering if there are other things i can do for the short term. Been trying to learn about the fscm and whether or not there are tweaks i can do there to band aid things a bit until i get the lt4 fueling. Am i going to need to unlock that anyway if i install lt4 low side pump?

Heard about others using a low side fuel pump voltage booster to make things better, even if its not a perfect fix...

Today's agenda... install the 3 bar map and do some more logging. Going to try a few more ignition timing tweaks, and increase the PE. Watch the fuel pressure.

Anyone know of indepth info you can pointme to about switching to lt4 fueling? I think im going to need the 8 injectors, high side pump, low side pump. Ive also seen mentioned about replacing the hp fuel supply pipe whenever injectors are swapped?

Tuning the FSCM can help to some extent but don’t expect any miracles. You could probably add a JMS voltage booster to the LT1 in-tank pump to get more out of that. And you can obviously continue to use that when you change to the LT4 in-tank pump.

The LT4 in-tank pump is pretty cheap and is needed first. You can definitely do that without doing the rest of the fuel system at this point.

The LT4 HPFP will be the next weak link. You should replace the high pressure pipes every time you interrupt them (two pipes, maybe $75 for both, see attached). I would also recommend the LPE high flow check valve to replace the very restrictive LT1 version. You’ll then do the LT4 injectors when you do the LT4 fuel pump because the operating pressure is higher (2900 LT4 vs 2175 LT1). Adding a cam at some point will let you get 32-40% more out of the HPFP.