ctgreddy

^^good idea

94StinkinLincoln

i have my doubts... what are you tuning it with? tweecer?

FuzzyDiceRule

nothing, like i said, hes tweaking the timing and fuel **** manually, hes not the one who does the tuning on the comp

Hamutoff

lets look at the low engine speed / low demand & the injector question of "24# too much"

What we are worried about here is the mininum time the injector is able to pulse - at very low demand. If the minimum the injector able to output is too much for the idle demand of the engine, there will be more fuel per air then is optimal (rich condition) and no way to correct it by simple tuning (fuel pressure, ign timing).

I was going to seperate points by low demand and high demand but I think that as long as the low demand part is met then there is no issue here of TOO BIG at high demand because as the engines demand for fuel increases - if too much fuel - the computer will read that from the O2 sensors, cut injector pulse back, but will never have to cut more than pulse at idle (low demand)

If 30# can idle stock-like on a stock 5.0 engine [see my prev post] then those 30# would have even an easier time with a modified engine - that can use more fuel even at idle, such as a stroker.

Heck, a 87-88 t-bird 4 banger turbocoupe uses 36# (the turbo is a non-entity at idle).... If 4 x 36# can idle (good enough for CA emissions) on a inline four (which is not going to idle as smooth as a V8), your source must be mistaken if he thinks that 24# are "too much".
As mentioned the 1993 cobra runs quite well with the 24# of course = CORRECT calibration

1 Q 4 U: What MAF are you using?

What I have concluded is that there is really no reason to ever buy 24# injectors for 5.0's. If you are keeping stock or going max MPG no reason to upgrade (clean or replace broken 19# yes). If you are going to upgrade then min. get 30# then you can grow to about 400 hp; the limit of the injector, and the block (and some say the factory fuel lines max out here too). This will keep it totally streetable and still possible to get the best idle available to a 5.0. IF you need more you have entered a different game at this point: basically cant keep a stock as cast block....

Example clean injector in good condition working at 100%:
19 @100% = 304 HP
24 @100% = 384 HP
30 @100% = 480 HP

The preferred duty cycle is about 85% maximum, so for a safety factor multiply the final figure times .85.

19 @80% = 258 HP
24 @80% = 326 HP
30 @80% = 408 HP

94StinkinLincoln

im asking what is the tuner using... like tweecer, pms, sct?

samseed101

If you're going to get a tune, which you should be getting anyway, then he should not be messing with the timing or the fuel manually. He should leave it all to the person doing the actual tune. Just to repeat what I said and what Hamutoff already said... you can run 30# injectors with absolutely NO problem on a stock engine. If the tuner feels it was running too rich, then there are several ways he can make changes to lean it out exactly where it needs to be. You don't even need a wideband to do it... at least not in closed loop.

For the longest time, I didn't use a wideband to tune my MAF Transfer. Sure it took a bit longer because I had to wait for the KAMFR values. But it worked. Obviously after I got the wideband it was even easier.

In the end, I was using 30# injectors with a MAF that was calibrated for 42# injectors. And everything worked flawlessly. I simply leaned out the lower end of the Transfer and everything was near perfect.

Also like I said before, even though the car had nitrous, a procharger, methanol injection, and some other mods... none of that mattered when it was at idle or when it was being driven around town. That stuff is only a factor (generally) when in Open Loop at WOT.

In other words, if you can't figure out how to get 24# injectors to work properly (which is REALLY simple as far as tuning goes) then you probably shouldn't be touching them in any way, shape, or form. That is tuning 101.

94StinkinLincoln

samseed is tha man!

samseed101

Yeah, with his big bad Geo Tracker LoL

But despite the lack of a fast (or any) Mustang... I still actually know a thing or two about tuning, modding, and fixing them. Or at least I like to think I do!

93 LX FiveO

he doesn't know EFI cars.

94StinkinLincoln

ha ha a geo lol

that brings back some memories from high school...a buddy actually put his geo on the track, 5 speed power shifting and ran like a 18.2 and 70 something LOL
i whooped' em

dont let sam kid yal, i have read many of his old posts when i first got into tuning and he could make my head spin, he knows enough.