8:1 fmu

[Loonatic]

i've been reading on 2gnt and said that an 8:1 ratio will work on 8 or 9 psi, it that true?

 

[Locke]

Post a link please.

It could work with some goofy combination of FMU, slightly larger injectors, and a piggyback, but I'd ask, "Why?" If you begin having issues with your car and are found to be using a setup like that, the first thing people will blame is the fuel system. FMU's are bad enough to begin with; adding complexity to an already barely functional setup probably isn't wise.

With the price of that kind of a hacked up fuel system, you might as well have gone with a more upgradeable or supported fuel system.

 

[Loonatic]

i've been wanting to upgrade my fuel system, should i go with the s-fmu? (im sorry for the ignorance, im new at this)

 

[VelocitàPaola]

i've been wanting to upgrade my fuel system, should i go with the s-fmu? (im sorry for the ignorance, im new at this)

A bare-bones, cheap-as-it-gets fuel system consists of a 12:1 FMU and a Walbro 255lph HP fuel pump. This system, which uses stock fuel injectors, is good for roughly 8psi.

A step above the FMU/Walbro system is a S-FMU, Walbro 255lph HP fuel pump, a removed/disabled stock FPR, and larger fuel injectors. The limits of this fuel system depend on the size of the fuel injectors chosen.

 

[rstchris]

I would recomend a Wally255, 30# injectors, and an AEM fic. All under $500 and good tunability and best of all you still have closed loop operation.

 

[96TurboGS]

I would recomend a Wally255, 30# injectors, and an AEM fic. All under $500 and good tunability and best of all you still have closed loop operation.

FWIW (and my .02 cent), there is not a better alternative out there than megasquirt. The newest beta (2.1.0) (MS2) soon to drop offers far more options than the current release and it's very stable. It has everything you can ask for at a reasonable price and you build it yourself (you can find these kits at diyautotune for around somthin like 250 bones and use MSEXTRA web site to build it if you want to keep it cheap). I chose symtechlabs due to quality control and not knowing anything about it first starting out. Not to mention you can use closed loop (afr) correction at idle/driving along with closed loop IAC (eliminating the ecu all together with far less wires making troubleshooting a lot easier to find). Being that the code is open source (and users can add input on how well the code is working / what they want) there is no limit to what this thing is capable of. What I've listed isn't 1/4 of what it can do, the normal user wouldn't use half the options. When starting off, anyone can easily use previous posted msq's on Pauls site making it even easier. Not to mention using spark with fuel is awesome.

MSQ File Repository - SymTech Laboratories: Design, consulting, prototyping, and manufacturing - Megasquirt - FCD's - Manifold Spacers

 

[Loonatic]

will it still pass emission with megasquirt?

 

[96TurboGS]

No, that would be the only down side to msns, but the reason why I said something was because of the fic's spark feature. It's not directly connected to the coil witch raises my concerns tuning wise, most people that are running one, (420a variant) run it for fuel. If you had something like a PNP or designed a swappable harness/PNP that would be easier to swap out during inspections, then you should pass inspections without a sweat. You just have to be creative.

 

[rstare]

MS is not OBD2 compatible.

 

[Loonatic]

ok, I'm going to rebuild my engine next summer, and i want to run at least 15 psi, but i still want to pass emissions, if use the s-fmu and larger injectors it will still pass right?