torqmonster

Here's what I have: 98 12v Auto, doing a 5 spd conversion this spring, putting in a dual disk clutch, BHAF, HX-40, #10 Plate, 4000 GSK, Gauges.

Up to how much HP can a stock 12v lift pump handle?

I'd like to shoot for the 500 hp range over time with mods, and I'm thinking about getting injectors. I'm looking into DDP 75's, 90's, & 140's. Is anyone running any of these injectors, with what done to your truck and how do they react? I'd like to only buy one set as the mods continue. Just wondering if I went with the 90's how they would react with my current setup and if I could reach my goal with them.

Any input or opinions welcome. Thanks.

STate

The stock 12valve lift pump will support up to 400hp. Cant help with the other stuff as I have not started to mod my truck yet.

patdaly

Pretty sure John P was over 600 before he went away from the stock LP.

BigErksG2

Go for the 140hp injectors and just cut fuel back when you run the hx-40 with the fuel plate. Keep your stock delivery valves. Down the road you can easily hang a 3b or s400 under the hx40 and have a towable 500+ hp. You can build a set of twins for around $1k if you have some mechanical knowledge and the right tools. Your stock lift pump will be fine however I have seen many fail when people stretch the return valve spring to get more pressure from the stocker. Put a gauge on it and leave it alone.

torqmonster

That was in my thoughts as well, I have an S400 laying around and my brother starting fabbing some mounts for twins, just have to make time to finish them...thanks!

Mcmopar

I'm a bunch north of 500 now and am still on the stock LP, run New Era 435's, I love mine!

BigErksG2

O-ring and stud your head so youre not playing russian roulette everytime you hammer down on the twins. Keep the boost below 45-50 if you are running twins on a stock head because if you are like me, you will get the twins done and cant wait to drive it around and try it out. My stock head held over 60psi at 16.5 timing a few times and didnt let go but I only "tested" it out because my truck isnt my daily driver. Keep the single hx40 around 40 psi. Have fun and good luck!

torqmonster

Yeah my HX-40 is from PDR and is wastegated at 40 psi.