91chevz71

So, I know that a BPC of 95 gives me good VE values. I thought that seemed a little high for having 90 lb inj's, so I suspect the fuel pressure is lower than 13 psi. My math gave me a BPC of 92.4 with 90/s at 13 psi. Since my BPC is 95, I did some reverse math crap and found that my injectors are actually pushing 87 lb/hr. 87/90 x 13psi=12.56 psi actual. I'm thinking about turning up the FP a little to 15 psi, turning my 90's into 108.75 lb/hr's, dropping the BPC to 76.4. In theory, if I up the FP and plug this new BPC and make no changes to the VE things shouldn't change too much, right? I'll probably have to reduce AE because of the higher FP, I think. Is there anything to be gained by increasing the FP? (besides more HP available)
Mike

91chevz71

guess i'm just posting to get fresh eyes on the debaucle that is my truck...lol it's become a freakish obsession. Obviously, I'm not the only dude with it. My laptop screen has a permanent burned image of the EBL Whatsup display...lol

RFmaster

91chevz71

New flow rating = [square root of (new pressure /old pressure)] x old flow rating

Re-writing above formula to find new pressure:
[New flow rating / old flow rating] = square root of (new pressure /old pressure)

Square both sides of equation
[New flow rating / old flow rating]^2 = new pressure /old pressure

Multiplying both sides of equation by old pressure
New pressure = old pressure * [New flow rating / Old flow rating]^2

If you crank up FP from 13 PSI to 15 PSI with your 90 lb-hr injectors

SQR(15 PSI /13PSI) x 90 lb-hr = 96.7 lb-hr

91chevz71

hey, there's the formula. I've been looking for that for an hour or so. I knew there was a square root in there somewhere
thanks for replying, RFmaster greatly appreciated
Mike

91chevz71

Allright, here it goes. FP is now 14 PSI, new BPC is 88. Lets see what happens. Checking the FP with a BPC of 95 and BLM of 128 for the most part=11 psi (stock regulator). AFPR is on now, 14 psi. Got a feeling it's gonna run real rich. Is there anything else I should change immediately with a FP change?
Mike

91chevz71

Results- after running rich across the board with 88- changed to 83 and VE is stable at 14 psi with a BPC of 83. here's couple pics

MikeIMG_1754.JPG
IMG_1756.JPG