FMU and Stock Injectors
 

Alright so here is my dilemma type issue. I have been reading and reading about fuel management and all the different forms and blah blah. I am wondering if I use an FMU with my stock injectors will I be ok boosting around 6-8 psi. I am using a t25 turbo off of an eclipse on a D16Z6 Engine. My other question is if I use dsm injectors do I have to use a VAFC or a chipped ECU or will those with an FMU work alright. I know I should be doing it a different way but I am on somewhat of a budget. Any input would be greatly appreciated.

Re: FMU and Stock Injectors
 

To use the bigger [390 or 450] DSM injectors you need a means of controlling them like a SAFC,VAFC chipped ecu etc.If you cant afford that a FMU will work for low boost 5-6psi but you really should not go much higher than that.A aftermarket fuel pump is recommended due to the high pressure demand of a FMU.Good luck.

Re: FMU and Stock Injectors
 

FMU + high pressure fuel pump is about $200 give or take. Piece of ---- fuel managment

Chipping Kit $25. Chip Burner $45 DSM 450's $50 = $120. Tuneable like a mofo. No cutting your stock fuel lines = teh win.


* you cannot run anything other than stock injectors without an AFC or chipped ECU.

Re: FMU and Stock Injectors
 

Does a FMU do the same thing as an adjustable fuel pressure regulator? Because I already have a fuel pressure regulator.

Re: FMU and Stock Injectors
 

An FMU forces your stock injectors to act like larger ones. It wiill increase the flow of fuel in the rail at a set ratio per lb of boost. From my readings, FMU leads to horrible tuneability, along with negative impacts on MPG and idle. Once you reach high boost, the ratio becomes undependable and will not supply proper fuel. You also run the risk of destroying your little injectors.

Re: FMU and Stock Injectors
 

word for the price of setting up with an fmu I still wonder why people even bother :1

Re: FMU and Stock Injectors
 

Because a few of us don't have the luxury of a chipable PCM. And on my vehicle, if I change the MAP sensor's value too much by using a SAFC or similar device, the ignition timing is way off, causing much worse problems during boost. So my only real options are to use larger injectors with two different regulators (AFPR and and adjustable FMU) or to go with a complete stand-alone system. I went with the least expensive of the two for now. If I really need to, I'll add a SAFC to the setup to help with the fine tuning of the fuel delivery. Just as long as I'm not making huge changes I will be ok with this setup.


Wink

Re: FMU and Stock Injectors
 

an FMU is just to save a few bucks in the beginning, but ending up costing you a lot more later.

Re: FMU and Stock Injectors
 

ive run a fmu 5 year ago and never had a problem stock gsr and over 500 pass at the track and 60000 km lasted two year it made on the dyno 322 whp tq dont remember
this was on a stock ecu and injector and we put a msd dis 6plus to retard timing

for the proper set up for the fmu changed the stock pump most of them has high milaged

list needed
mising link or check valve for the map sensor fot it not to see boost

255 liter per hour walbro in the tank

msd high pressur pump [ booster pump]

we where running a 7 to 1 fmu made by us but it all depend on the size of turbo
u need all high pressur fuel hoses and dubble clamp fuel pressure will go to 125psi

a igntion system that has nos retard timinn on it and we use a pressure swicth to activate it

i have a friend car now running for over 3 year now and it make 310 whp and 240 wtq
on a stock gsr

on a fmu set up make sure not to run the gas tank low on fuel wile under boost it will detroy the motor

the best set up is to program the ecu but if you dont have any person around to do it the fmu is a good set up

for the fuel milaged it the same under vacume and the fmu only works under boost

and the fmu will not work whit bigger injectors

Re: FMU and Stock Injectors
 

FMU's still suck ass

Let's see for FMU, you need 2 new fuel pumps, pressure switch, timing retarder, new double-clamped high pressure fuel lines and the FMU itself

For Uber/Chrome you need a chipped ECU and 4 cheapo dsm 450 injectors.

The FMU is HARDLY tuneable, except for the static psi/psi ratio while a little chipped ECU allows you to tune both your fuel and ignition maps.

Re: FMU and Stock Injectors
 

Yeah, anybody who says an FMU is a viable option anywhere, needs to grow a ------- clue.

Re: FMU and Stock Injectors
 

do FMU's install on the feed line to the injectors or the return line?? cause i read somewhere that it installs in line with the regulator on the return line..but someone said that it installed between the filter and the fuel rail...

Re: FMU and Stock Injectors
 

On the return line.

Re: FMU and Stock Injectors
 

450 cc injector are only good for 260 whp
i ran 11.75 at 120mph on a stock block all stock no piston no rods the motor was never taken aparts whit a fmu and stock inj and ecu in 2001 in a 95 civic hatch wieght 2560 whit me in the car and lasted over 60000 km and beteween 340 to 375 mille per gas tank it noe the best set up but it does work if intall properly


the fmu goes on the return line and tie rap all the vacum hoses so they dont pop off

Re: FMU and Stock Injectors
 

Yea. And I guess you missed the fact that not all cars have the option of an ECU hack like you honda OBD0 and OBDI folk have it. No one has cracked the code for my car yet. So the one of my options do include a FMU. Six additional injectors sound great. But not very easy on my intake manifold setup.

Re: FMU and Stock Injectors
 

well my comment wasn't really meant for people that don't have any other options :-\

Re: FMU and Stock Injectors
 

thanks..a useful bit of information..i thought that FMU's could[/b] be used with larger injectors?? correct me if im wrong and explain..thanks

Re: FMU and Stock Injectors
 

fmu works by increasing the pressure
you could put a bit bigger injector but it would ---- up your idle and normal driving
if you cant program the ecu pulse with and you would have to changed to a lower ratio
instead of running 10 to 1 you would try 7 to 1 fmu

ive tried 330 cc on my gsr 4 year ago and it would run under boost it would flood it
and the stock gsr were 240cc

Re: FMU and Stock Injectors
 

All engines are basically the same even if the electronics aren't. Fit a different ECU.

Re: FMU and Stock Injectors
 

\


Might as well go with a stand-alone ECU. Either way, I'll have to redesign the entire engine's wiring harness.

But not an impossible option.