BEATurBOYS

what would happen if i ran a FMU on a non turboed SOHC motor?

if theres bad i want to know, if theres good i want to know...

thanks...

forcefedferio

for what purpose?

BEATurBOYS

I WAS CURIOUS IF IT WOULD GIVE ME BETTER FUEL PRESSURE THATS ALL...

dpetro1

an fmu or rising rate fuel pressure regulator increased fuel pressure with positive pressure so it will still increase your fuel pressure as pressure increases (vac closer to 0" for NA). the honda fpr is already 1:1. if you installed a higher rate 4:1 or 10:1 or whatever then you would need to tune for it and even then for NA you would probably be running too rich.

in conclusion i would say NO, there is no benefit to using an FMU on an NA car. hell we dont even use them on turbo cars anymore.

97twodoor

If you want more fuel pressure then you need and adjustable fuel pressure regulator. Putting an adjustable regulator on a stock engine, or even on an engine that has been slightly modified you will see no benefit. The reason an FMU will not do anything is because it operates on the principle of raising fuel pressure a certain amount per 1 psi of boost (1:1, 2:1, 3:1 etc.). You mentioned nothing about a boosted engine in your post, therefore by adding an FMU you accomplish nothing. The fuel pressure will stay the exact same as stock.

EDIT: ^ Beat me to it.

forcefedferio

why the angry response? i was just asking as in if you were planning on going F/I or doing an N/A build or what.

BEATurBOYS

My bad. The caps lock was on so i just left it. You all have very insightful info. No pun intended.

To the other guy. So even a fpr would be a waste of money on a stock motor?

Also just so everyone knows, i have some of these parts laying around so i thought id try to experiment with it.

What does the missing link do?

CivicSpoon

The missing link: http://www.inlinefour.com/missinglink.html
Basically it's for boosted cars only, and worthless for a NA car.

An FMU is worthless period, it's a hack job way of increasing fuel. An adjustable FPR is pointless for a stock engine, because the stock one is giving the engine enough fuel for what it needs. Simply adding more fuel, when the engine doesn't need it, will actually HURT your performance. Even with basic bolt-ons (intake, header, & exhaust), the stock computer will compensate enough fuel for the increased air flow. The only time you should really alter the fuel pressure or increase of fuel, is if you have modifications like forced induction or install higher compression pistons. Even in those circumstances, you don't simply add more fuel and call it a day, you need to alter the fuel and ignition timing maps (aka: getting the car properly tuned).

dpetro1

a missing link is a check valve that blocks the MAP sensor from seeing positive pressure (boost). a stock honda ecu will throw a CEL if it detects positive pressure. thats why you see the fmu and missing link used together.

again, both items are pointless on your application