running rough!!

[SappySE107]

That chart is wrong according to the calc in HPTuners, and the stock fuel injector constant in the OBD2 computer as well. 21.3# @ 55psi is what a 19# injectors becomes when it was rated at 43.5psi.

[robertisaar]

so what are the real ratings?

[Rootie524]

ok so i have a 2002 car..so my rail is 55psi..if i use 19# injectors it will give me 21.5#..i need 22.5#..but that's close enough, right? because my current injectors aren't even close to their full duty cycle.

[SappySE107]

They M2 3100/3400 injectors are 200cc/min at 43.5 PSI. That makes them 21.3# at 55 psi stock. 22.5# is wrong.

[Rootie524]

ok so although places say 22.5# it's actually 21.3# and the 19# would be a direct swap?

[SappySE107]

Injector connector is different. Unless you just wanna be cheap, I would get the M2s checked/cleaned or buy the set I have on wot-tech that is already cleaned/tested. The older style should work at the higher pressure but they were more prone to clog and mess up the spray pattern.

[Rootie524]

I'll probably end up getting them fro your site then if i need them. i was just trying to find out worst case if i needed them in a pinch if i could use them. but everything is back together and its running great so far.

only issue is it seems horrible on gas. i know it is to begin with but this is just bad. i filled it up and it was alittle below half a tank..i drove maybe 30 miles and its close to quarter tank..maybe i just think it's bad or something, idk.

all i did was install cleaned up heads with minor port to get rid of bad casting, new valve seals, cleaned and lapped valves, the same comp springs i had before, cleaned lim, and everything else is good. same injectors and all that...

and dont tell me its because of my port job because i barely took anything off..just enough to clean it up a bit..and its even..trust me.

so i can normally get over 200 miles to a tank..so im gonna fill it up and drive a bit and see what happens. but for now it seems off...but it may just be my imagination..so far though..problem is gone..i think that lifter springs screwed crap up and that would explain the higher compression on cyl 4 if the valve wasnt lifting as high as the other..and that probably threw off the fuel injectors and stuff..so i think its fixed!! now i can get on and build my 3400!

[86FieroSEv6]

Remember, it is a fuel LEVEL gauge, not a fuel VOLUME gauge. Due to the shape of the tank, the "top half" does not hold the same volume as the "bottom half" and all points in between. The only way to know is to do the hard numbers, you know the routine. Fill it up, note the mileage, drive it, fill it up again and note how far you went. Divide gallons into miles to get your bad/good news.