I use ls1 edit and am striving to understand everything so i can tune the best i can.

please read this and tell me if it sounds right.

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4.2.1.1 Injector Flow Rate

This table defines the size of the fuel injector. It should be modified only if you replace the Fuel injectors, or change the fuel pressure.

If you change the fuel pressure, you can calculate the new injector constant use this formula:
RatingNew = (sqrt (PressureNew/ PressureOld)) * RatingOld

The table shows the Fuel Flow rate in Grams per second, as a function of the intake manifold Vacuum in Kpa
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When i installed my whipplecharger, i upped my fuel presser about 4psi.
My Old pressure was like 59 and my New presure is 64. My stock flow rate is 3.18

So.... newpressure divided by old pressure is 64 /59 = 1.085
the square root of 1.085 is 1.042
So i multiply the square root by the old flow rate to make the correct value.
1.042 times 3.18 = 3.31
Therfore, my new rating would be 3.31

Does this sound correct? and do you think it will show any difference in power?

 

it is unlikely you will see any increase in power. for small changes like you are talking about the computer will make adjustments(ltrims) and get the perfect a/f ratio at part throttle. under full throttle the number you are talking about will effect your fueling but with the whipple set up you max out your stock injectors right away so the factory ecm really isn't controling the fuel anymore. i am guessing you still have the whipple fuel set up.

the hot ticket for you would be to ditch the whipple fueling, get some BIG injectors and do your own tuning with LS1edit, then you could efectively adjust your a/f ratio and would most likely see some power gains. i went thru this process and could help you thru the steps.

tuning with a wideband 02 set up realy makes for an acurate tune and if you plan on going all out with the truck you might want to go that route someday.

 

Of course id like to go all the way with my setup, but i just dont have the time or the convience of another vehicle. if i have any down time on my truck dew to constant mods and tuning and tinkering, then i loose in the neigerhood of $200+ bucks a day. I run a floorcovering installation business and use my truck every day. Im just tring to figure out my my whipple offers me no real performance gain.
i only gained 3 mph on the 1/4 mile. It also has a hesitation in between 2700 and 3000rpms
Im wondering if the whipple computer is broke or something cause everything on ls1 edit and atap seems to be ok. although i have no idea what the o2s are suppose to be. Lets put it this way, the only way to chirp the tires is to hold the brake and rev it up to about 1800rpms.
Everyone else seems to talk like this supercharges offer jaw dropping performance.
Man if you have any ideas as to my problem, do tell! I have all the info on my computer so i can give you most all the readings of my trucks tuning and what my sensors are saying under acceleration. Even the guys at Whipple said 1.5 second gain should be normal.
Another person said he gained a second in the 1/8th. Im just venting a little here cause ive had enough. Thanks, Drew

 

i dont remember your entire story but the time in your sig looks prety good to me. with all the heat related issues and blowers i am not sure i would go that route if i lived in texas. anytime it was over 80deg i didn't even try and go fast with my truck, the heat just killed it and i bet it is hot as hell down there right now.

send me one of your atap logs and i will take a look, i want to see one of a full 1/4mile run. cobra99vert@aol.com

i had no down time with my truck and the tuning. it takes some time to tune but you can still drive it while your learning and messing around.

 

Parish8,
What size injectors would you recommend to be able to remove the 2 whipple injectors....I assume that is what you did. Those are really the only thing controlled by the whipple computer right?