4drhoar

so i brought my car to see chris at nrg tech today for a tune.

setup is

cp/eagle stock sleeve b18b block
stock gsr head and cams
vic x intake mani with 70mm tb
divided topmount, hx35w 3 inch dp
walbro 255 pump aeromotive fpr precision 780s


we strap it down car is seemingly running strong. im running off 1 bar wg springs, we go to make a pull and its kosher up to about 6500rpms and then starts going lean. we check the duty cycle and it was around 95 percent.

15 psi came in at 4500rpm pulled clean to 6500ish then the car seems to max the injects

at that point it made 320 hp 245 tq

seems awefully low to be maxing a set of 780s. unless the setup is just that efficient and does destroy fuel like this.

we tried a different know good walbro, checked flow, car held solid 65psi rail pressure under boost. tried a diff distributor, wires ect. nothing made a difference. the pulse width was around 16.2 milliseconds

no cels, no funny business. just seemed abnormal to both of us, and unfortunatly we didnt have a bigger of dofferent set of injectors.

im going to scoop up some precision 1200s and try again. anyone have any input on this situation??

tony1

If your setup uses a lot of fuel to make a given amount of power, it's inefficient, not efficient.

I'd put some ID1000's in it and call it a day.

locash

Sounds like you dont really have 780cc injectors to me. I'll agree with tony here, screw those crappy Precision injectors and get the ID1000cc..

smoovy

I wish I would have gotten a set of ID100's before I got tuned!!! oh well. well, just a stupid question but do you have a resistor box? or some type of FJO driver of some sort? didn't mention what car or year this is? these injectors are peak and hold to my knowledge.

EARLdaSQUIRREL

those injectors are good for over 400whp, i would try a different set or have yours flow tested

srmofo

I got another set of BNIB 780s if you wanna buy em. I upgraded to the ID 1000s before I even installed the precisions.

But to me that does sound awfully low to max out those injectors

miller

I am still sold on it being the injectors, the girls car after you made more power with less injector and only 68% duty On a serious note, put those other injectors in you have back home and do like we talked about and you will see what is going on from there.

BTW I threw up twice tonight with the methonal car that showed up as you were leaving. I was psyched to go home and I ended up having to help tune it.

4drhoar

yea chris i agree. what did that meth car make for power? sure looked serious enough sitting there. btw daniella has your plug wires still and we forgot to take ur wideband sensor out of my downpipe.

we will mail you these things back asap. going to mess around after work today. ill report back with my findings.

thanks for the input guys

4drhoar

its a 95 4 door and i do have a resister box intalled. id1000s i take it wouldbe better choice than a set of precision 1200s?

my gut tells me these 780s are not flowing 780cc worth of fuel. i wouldnt even be surprised if i was sent a smaller set when i ordered the 780s. stampings on the injectors match as i called precision to verify, though

Blown90hatcH

Yes get the 1000s from Tony.

You called precision to verify those injectors? Send them back to them to have them tested and see what they say.

smoovy

id1000's!!!!! I want a set, just read about them. I want to get rid of my Precision 880's!!!

locash

Smoovy knows where to get the ID1000's, right back at your tuner! Those Precision 880's you have are cursed, the only injectors I have more problems with are the 1600's..

4drhoar

ill call precison and see what they have to say.

if the walbro 255hp is known good, and its got a new fuel filter, holding 70 psi steady rail pressure at 15 psi boost. and the ignition is working properly, i guess the injectors are the only other questionable... well see what happens.

4drhoar

is it possible a voltage drop at the pump would cause this also?