MelloYellow

Can anyone confirm my injector scaling numbers for Mototron 60's?
I show they run as 72# at 58psi.

MightyMouse was using the following scale: (Mid-Range)
7.87 7.89 7.91 7.94 7.96 7.98 8.00 8.02 8.04 8.06 8.09 8.11 8.13 8.15 8.17 8.19 8.21

But when I use some of the injector calculators @ 58psi, I get the following:

Speed Demon Injector Calculator: (Rich)
http://www.speeddemonmotorsports.com...ectorscale.xls
5.39 5.42 5.46 5.49 5.52 5.55 5.59 5.62 5.65 5.68 5.72 5.75 5.78 5.81 5.84 5.87 5.90

Tech-LS1 LS1Edit Fuel Injector Calculator v1.4: (Leaner)
http://www.blackls1ta.com/tools/JohnsInjectorCalc.xls
8.73 8.78 8.83 8.90 8.95 8.99 9.04 9.09 9.16 9.19 9.26 9.31 9.36 9.40 9.45 9.53 9.55

99Fbody99

THe second scaler you posted is the 42# ( at 3 bar) bosch. THe motrons are 60# at 3 bar..You are correct that when running at 58/60 psi they will be 72#.

THe Mighty Mouse scaler should be pretty close to start with.

Dave

MelloYellow

Did MightyMouse scale for 58psi or 76psi fuel pressure?

There is a huge difference between the 3 scales.
Anyone want to comment?

Are higher scaling numbers leaner or richer?
Leaner?

MIGHTYMOUSE

iTrader: (59)

my one has been run in more than a few cars and is very close if not fine for everybody so far. i would certainly think the first one is way too rich (5.x) and the other way too lean (9.x)


on the referenced regulator i ran the 7.87 all the way across, however since you are using the stock regulator you need to put the slope back in it (going to the right) to trim fuel as the vaccum increases at the injector tip.... and you found that one too.. good digging

MECHAM

iTrader: (4)

richer!

****..i left my ls1 edit laptop is at my friends...i have been scaling it back and back...those first set of numbers is about where i am at now.

according to my wideband..as soon as i hit wot...it pegs instantly to rich..and stays there until i left off...

actually..i am in the low 6.xx's now...i was at the 7.xx range


****...i just read MM post..should i be going towards the 5 range or higher?

MIGHTYMOUSE

iTrader: (59)

if you are wanting to lean the car out part throttle you need to move the numbers higher numerically.

the numbers mean how many grams per second (i think.. long time) the injectors can flow..

if you tell the computer they can for a bunch per second.. (higher number) it will not hold them open as long) (lean it out)

MECHAM

iTrader: (4)

aw crap...i loaded the first set of numbers 7.87 all the way across and it was still reads rich at WOT. guess i will up them to 8.00 all the way across.


question....if i am in 3rd gear during a WOT run and the wideband pegs to rich...if i run in 4th gear will the wideband still peg to rich? is the load different in 3 vs 4?

MIGHTYMOUSE

iTrader: (59)

load is a little more in 4th.. also a little more time to drain the lines if your pump is having a hard time keeping up. keep your third eye on the fuel pressure.

sc mecham.. what is your particular fuel pressure set at.. static 58 or boost referenced..

if referenced then with the vaccum unhooked set the psi to 60, it will trim down to 50 or so at idle and go above 60 1psi per psi boost. this is when the 7.87 is close straight across. if 7.87 is rich all over part throttle (big negative l trims) then go to 8.x
if your displacement is different please do adjust that in edit as well (i say this because 7.87 should work fine)

if you are talking about being waay rich when you smack it (after you find your l trims sligtly negative) then you need to move fuel around in the p.e table vs rpm. in that table the higher number means more fuel dumped... take that number in the pe table and divide 14.7 by it to get your target air fuel ratio. for example 14.7/1.2= 12.25:1 target air fuel ratio.

make sure your maf is pointed the right way, and the maf curve in edit is untouched and correct for the maf you are using. if you have a 99+ extrapolate the maf curve best you can by fooling with the points after where it flattens off so it continues up to 511.99 grams/sec. that will help (some) with high airflow fueling

if you have a 98 you are on your own after maf hz of 11,250hz.. please log maf hz during your pulls so you will know when your engine is counting on you to lie to the p.e. table to make fuel and not the maf. 99+ runs out at 12k.

MECHAM

iTrader: (4)

fuel pressure is boost reference and when the car is at idle it read ~58-60

i got dual intank stock pumps i got two 255's but since the car is not leaning out..i figured i was ok with them for now.


ok...so
1. set my base pressure at idle to read 50psi
by the end of my run it should be aroun 60+ psi
2. use 7.87 all the way across the inj scaling

i want 11.5 A/F for now so...
3. 14.7/1.27 = 11.5x

i have a 98 so got screwed on the maf

is logging the maf g/sec also going to tell me when i am running out of maf and the pe vs rpm is going to take over? if i log the maf it will read something like this...

MIGHTYMOUSE

kp

iTrader: (34)

This is what I am using on the last D1SC A&A car with 60's, I started off with a little lower numbers but this is what I ended up with to keep the ltrims a little negative. Stock 2000 descreened MAF with a racetronix in tank pump, stock regulator. It was good enough for 655rwhp at 13psi..

8.52 8.57 8.61 8.68 8.73 8.78 8.83 8.87 8.95 8.97 9.04 9.08 9.13 9.18 9.22 9.29 9.31

MelloYellow

Thx MM + everyone!

Any difference with a C5 throttle body at idle?
I swear I never see 50-52psi at idle.
Stays right around 62psi since I'm direct wired at 14v to the pump.

Other Reference, I believe BIGBOS was using the following scale, but it looks like 2 cells of data are missing.
Looks Rich: 5.83 5.87 5.91 5.94 5.98 6.00 6.05 6.07 6.11 6.15 6.20 6.24 6.28 6.31 6.33 ? ?

kp

iTrader: (34)

50-52psi at idle is if you have a boost referenced regulator, if not you will be at over 60psi at idle like you are.

I didnt get any numbers from A&A, I just used one of the injector calculators and kept moving the numbers until the ltrims ended up where I wanted them since the MAF numbers looked pretty close to where they should be. Where you MAF is located will make a big difference as well as having a screen or no screen plus if you change the MAF tables it affects everything so its really hard to use someone else's tune other then a ballpark.

MECHAM

iTrader: (4)

thats because we are using an external fuel pressure regulator and removed the stock in tank regulator so we can adjust where the base fuel pressure will be and it will rise 1psi per psi of boost.

i know for a fact that is rich..unless his base fuel pressure is like 40psi

MelloYellow

Thx guys!
I think our numbers will be between MM's and KP's.

This was mostly a sanity check. To add to our confusion, the Dynojet Wideband sensor failed today. They've had it happen before and ordered a replacement due in Tuesday.

WB was saying 16:1, but had no KR and was blowing black puffs out the back so much have been rich. Just confirming the injector scaling and archiving scaling data in case anyone else searches. The WB kept going out of calibration slowly over the past couple days... driving our tuner crazy.

MIGHTYMOUSE

iTrader: (59)

SC. while you are under the hood screwing the regulator out, UNHOOK THE VAC LINE and THEN turn the screw until it sits right around 58-60... then hook the vac line back up and whatever it gets, it gets.

also SC dont forget, that the p.e. table only works right up until the maf stops.. after that you will have to add even more fuel in linearly with rpm.. supercharged guys will have to add fuel exponentially after the maf max's.

in the long run it really doesnt matter, but setting the base pressure lower will give you more room on top to add boost psi.

mellow, if you have the static regulator then yes use the first one of mine you posted.

in kp's case, the descreened maf could be the reason you are having to lean out.

Armageddon

iTrader: (41)

MelloYellow

Follow-Up.
KP's scaling worked out best for us.
8.52 8.57 8.61 8.68 8.73 8.78 8.83 8.87 8.95 8.97 9.04 9.08 9.13 9.18 9.22 9.29 9.31

Headache was bad dynojet wideband. Was showing 16:1 Lean and puffing black smoke, showing no detonation and smelling rich.

New wideband arrived today and A/F is Rich off the scale below 10:1.
Back to dyno tuning.