Flame away if need be, I understand this method of fuel management is garbage against today's tuning technologies.
This is my first forced induction build it is an experiment (hence why i'm starting with a fmu).

I've collected myself a custom turbo setup and was wondering on a stock b18b1 will the oem fuel pump work or should I upgrade to a Walbro 255 lph if my plans are pushing 8psi of boost on a 12:1 fmu. =]

 

according to your location you live in texas. Im not going to advise you to use an FMU. You have enough tuners here in texas to do it right. If you use an FMU you risk the chance of running very lean or very rich. Usually lean.

take the time to read in the Engine Managment/tuning forum that will help you make the correct decisions

 

your logic of starting with an FMU as an entry level fuel management is faulty. FMU's are not a starting point, they are pretty much obsolete at this point. its like saying you are going to start with a tape deck before you move up to a CD player, pointless.

but to answer your question, FMU's create high fuel pressures, you will need an inline pump up supply the pressure or a 255HP in-tank may hold up at low boost.

EDIT: actually i dont even think the 255hp will do it. 12:1 fmu x 8psi = 96psi + 38psi base = 134psi. the 255hp can only flow like 8lph at that pressure.

 

sum guys here added the walboro intake pump and used fmu and ran at 8-10-12lbs of boost just fine. they are low budget/super old skool drag racing/smell like smoke and drink alot beer type a dudes. works fine if you use them right.

 

this may be possible with a lower ratio FMU ex: 4:1 or 8:1 but not at 12:1. 12psi x 12:1 fmu = 144psi + base of 38 = 182psi of fuel pressure. The walbro flows 0 lph at that pressure, hell i dont even think an inline pupm can keep up at that pressure

 

the first 3 years on my car with a 255 (the hp one) and an fmu no issues, other than it being crap.

to answer your original question, no a stock fuel pump is not enough for the fmu. a walbro alone will work but an inline will help much more.

although i never ran my walbro at that high of a pressure, i did run it around 8psi.

 

You can physically run 12psi with an FMU and 255lph fuel pump (DONT DO IT THOUGH)... It will go lean and I have done it.. 7 years ago. The fuel pump does not stop flowing at that rate, basically because the fuel pump cannot push the pressure needed to return fuel to the tank it just stops the fuel at the fuel rail.

It is cheaper and safer to run crome.

You will find that your stock fuel pump cannot match the demand at about 4-5psi with a 12:1 FMU and it will start to go lean...

 

i recomend an adjustable fmu and wideband o2. and why not a meth/water injection kit. a guy that i was talking to about this subject( inwhich ive been considering myself) says it needs to be ran on a ratio closer to 2:1 from an fmu

 

I would recommend on getting it tune on an ems so you will get full potential from the turbo setup and throw the fmu in the trash lol

 

x2
you dont have to buy an expensive ems there are plenty of budget options out there that will save your motor and make you enjoy your setup that much more. I ran an FMU for 3 months before I developed a hole in a piston. Not saying the FMU was to blame but it sure didnt help

 

If you are really on a budget instead running FMU, you should just get:

DSM 440cc's
And get a chipped ecu w/turbo basemap from John Vega - HT member "MTBER".

You'd probably run a tiny bit rich, but you'd spend less than $150 for both.

 

i thought about that myself. all i would need was a chip. but how safe is that really? and like in my area what if none will work with anything other then hondata so you could get it tuned to a fine point?


and about the fmu: so nobody thinks it can be tuned close to perfect? im just weighing options and learning myself. so i would like someone to explain what i am missing. and i know its primitive mechanics but isnt it what people were doing before they realized they could directly hack ecus? i guess i just see it as doing the job manually. i dunno thanks guys lol

 

thanx for all the advice everyone.
My motor at the momentis showing low compression of 120-125 psi in all 4 cylinders and then shoots up to 150 psi after a wet compression test (so it must be something within the block, most likely piston or rings). I was wondering if I should go oem pistons or something lower... possibly even higher (lol)

 

Basemaps are far safer than running FMUs.

 

And then I've heard otherwise.just makes it hard to know were to put my money. But I guess spend money on a wideband and in my case get a base map chip for my setup and see how it mixes out. Wouldn be too bad untill I got some software on it myself maybe.

 

If u are on a budget you can run something like crome and find a tuner to tune it to get the full potential from your setup cuz im sure u will want more power in the long run.

 

just turbo'd my d16 del sol with 200k running 12:1 FMU and missing link @ 5psi 3days so far so good, but today car started to over heat after going through couple of gears, and also about running rich or lean, would i be better of with 9:1 FMU disk? and yes i know FMU's arent the best thing thats out there saving $ for hondata and tune

 

one word comes to mid when i see these silly questions


KAAABOOOOOOOMMMMMM

Or would that be catagorized as sound?

 

you should get a wideband to make sure.

 

2010.