disposablehero27

Forged internals, stage 3 MMR ported heads, intake, intake spacer, IRMC DELETE,BBK Long tube headers, BBK H-pipe, P1SC procharger, 3 core intercooler 1600cfm throttle body, and a few other mods. I'm not sure on the psi because of these questions. 96 Cobra with these mods. At the moment i am researching and purchasing items for the build. I had a plan of 500hp, however im thinking its going to be closer to 6/700hp. Right now I have an in tank 255lph fuel pump, the inline pro pump from procharger....(what is that LPH?) 60lb injectors, and a 90mm Lighting MAF. Is this MAF going to hold or able to be tuned around? how close are these 60lb injectors going to get me? and planning on bigger fuel lines, and rails... but the pumps? enough or way off?

Thanks in advance for the advice.

cliffyk

Litres/hour; 1 lph = 0.264 gallons/hour = 1.64 pounds¹/hour. So, your 255lph pump could theoretically deliver 418 lb/h of 93 octane fuel. Actual delivery will be more or less depending on fuel pressure and supply voltage--here's a chart of Walbro's standard pressure 255 lph pump delivery rates at selected voltages and pressures:



You can see that at 40psi the delivery rate is 58 (@12V) to 68 gal/h (@13.5V), assuming 13.5V thats 418 lb/h of 93 octane. Running f/i that will support 690fwHP, or 590rwHP--flat out with NO headroom, making 500rwHP a practical limit for that pump.

At 90% duty cycle and 40psi the 60lb/h injectors will be able to move some 414lb/h of fuel [(40/43.5)^.5 * 60 * 8 *& .9], Running f/i that's 690fwHP or 585rwHP, well over the pump's 500rwHP practical limit.

The Lightning MAF pegs at 3800lb/h or so, which is also the PCM's air flow limit. At 11.5:1 AFR 3800 lh/h of air would have 330lb/h of fuel being mixed with it. Running f/i, 330lb/h of fuel would support 550fwHP, or 470rwHP.



In summary:

• the 255lph pump can support 500rwHP;
• the 60lb/h injectors (if enough fuel were available) can support 585rwHP;
• the 90mm Lightning MAF can support 470rwHP;

Now these are all theoretical and rule-of-thumb based calculations. Real world results could be easily ±10%, they are nonetheless the numbers I would use as guidelines if setting fuel and air systems for a target HP.

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¹ - 93 octane gasoline weighs approximately 6.2 lb/gal at STP.

disposablehero27

hey thanks cliffy, now if i have the in tank 255 plus that pro pump inline with the charger kit.. whatever that is... would that support more HP? lets say if its a 255 in line... could i push more HP or doesn't matter, to much for the in tank.

97stanger

your build is very similar to mine. (97 GT, forged, MMR stage 3 heads, SI trim, meth, blower cams, edelbrock manifold, etc)

No way your 90LMAF will support that hp range
I personally run the SCT BA3000

As for an idea for fuel, this is what I run:
Dual Walbro 300lph pumps
y block
inline fuel filter
sumped tank
edelbrock fuel rails
8 feed lines, 6 return
adjustable fpr

I am expecting to be in the 600rwhp range thru a built auto fyi

disposablehero27

Thats awesome, very impressive. Yeah seems I need to get rid of the 90mm MAF, just not going to do it. May as well swap for 80lb injectors too. Not a huge deal. What about the second posted question, anybody know what the 255lph + a 255lph inline pump can handle?

disposablehero27

anyone?

disposablehero27

*****bump