Looking for pointers on ICP with 190/75s

So here is where Im at, I have an 06 with 190/75s from MPD. Also I recently had all the updates done in the HPO system. I havent been able to run a full hard WOT run, but I got it up there and seen 4.2v max on ICP and 95% on IPR. Im running Gearheads SRL+ tune. I was under the impression that I wouldnt need a larger HPOP or more oil with 190/75s.

FP is low around 45,) Im only at about 3/4 throttle ) and it can go lower but I havent pushed it past that. Im waiting for the weather to break to get the fuel system in ( I do have a RR installed as well ). Could there still be more oil left on the table since Im not at WOT? I thought ICP would reach its max around 3/4 throttle?

The other thing that has me thinking somethings up is the 95% IPR on all heavy runs. Shouldn't that max out at around 80% or so? IPR is 25% at idle.


What would be next to get the ICP up? HPODS? Thumper? :fustrate:

Well... This seems to be a question for the ages. Many injector builders claim that "properly built" 190s will hold ICP on a stock healthy pump... Others say 205s. Fingers often get pointed at the injector builder... BUT... IMO with our tuning abilities these day we are able to squeeze enough fuel out that 190s is pushing the stock HPOP.


I have lots of guys on 190s making good power from all different sorts of injectors builders... some 190/30, some 190/75, and some 190/100... Some barely hold ICP and others drop just a little bit.


Also most tuners that I have talked with don't see much of a difference between 90-95%... so if you are hitting 95% then you are using up pretty much everything the pump has. As RPMs go up it will help. The only way to know is to do a hard 100% WOT. I would go out and try some WOT runs before I get too worried.

What PW are you seeing at WOT... sometimes running too high of a PW will drain more HPO than needed. IF you can dump 190cc in 2.2ms then 2.4ms will just waste HPO. You might be able to pull back on the PW without losing any power and gain back some ICP.

you need to check ICP at full 100% WOT...not 75% throttle. Because ICP is based off rpm also. As rpm rises....so should ICP. You should ideally see around 4.7v @ 4K rpms. I think your 4.2v reading is around 3400psi or so.

Yeah, then I'll put this off until my fuel system is installed . I thought that ICP would hit peak before that.

U can go wide open throttle Anthony just dont stab it. Ease into it

Drops far. I'm not taking it past 45

it wont hurt a thing but ok

Below 45 won't hurt? Lol damn near all injector builders caution low fuel pressure

it certainly will not hurt it for a quick run.... for what its worth, our 450 ran 5 hours last weekend at fuel pressure below 30 up steep hills(fuel pump is getting weak). ran like a champ. so once again quit worrying.