MR_EJ8

Just as the topic says, does anyone have any info or experience with these things???

Search isnt working.

Im building a low boost/budget turbo kit for my civic and this thing is only 200 bucks and suppose to be really good. Its a fuel pressure regulator and fully adjustable 1:1 all the way through 12:1 fmu all in one. and its only a little bigger then the stock civic fpr.

http://www.nipponpower.com/product.phtml?p=771

MR_EJ8

Anyone??

rorik

I don't have any experience with it, but after looking at the ad, I have a couple questions.

They say a diaphragm slows the response, but how could it when all the force being exerted on it is pneumatic and it is directly coupled to the valve unit that restricts the flow? I say how many psi of manifold press does it take to move that piston in their design, with no load on the other side? In other words, say it takes exceeding 2 psi to overcome the internal friction and get that piston to move, then your manifold press could rise 2 psi, and your fuel press wouldn't, until your manifold press increased slightly more than that 2 psi. And they say their regulator doesn't overshoot/undershoot? Sounds like bs to me, unless their piston is amazingly more sensitive than a diaphragm, which I highly doubt.

rorik

****, I just drilled a bypass hole per endyn's instructions in my stock regulator to allow it to accommodate my walbro pump..but it would be kind of cool to be able to ramp up my pressure under boost, get a little more out of my injectors..

Synapse

Rori, in a way the Synchronic FPR is less sensitive than a diaphragm regulator. It responds like a diaphragm regulator to vacuum, but it is less impacted by the peak pressures, and acts more on the mean pressures. With a diaphragm regulator the diaphragm is more flexible, so it can go sideways up down, etc. The Synchronic piston only has one direction to move the Z-axis, it is restricted on the X and Y axis. So there are only two factors that impact the movement of the piston, pressure on the acting surface area and friction on the seal.

Where it is absolutely most responsive is with boost, it immediately reacts to changes in boost pressure compared to a diaphragm regulator. Even at just .5 psi of boost, it will raise the fuel pressure accordingly. With a diaphragm, the diaphram has to deflect before acting on valve to raise the fuel pressure under boost. And if you think about it, you have 40 psi of fuel pressure on the other side of the diaphragm for your boost pressure to fight against. Which is why diaphragm regulators need such high spring rates to bias it. If you've ever taken a standard FPR apart, you'll notice how much preload those springs have. Synchronic does not need that much pre-load at all.

Here's a pic, of 1000 samples per second on a datalogger. You'll notice that Synchronic doesn't have as much hysteris with fuel pressure compared to a diaphragm unit.

Synchronic is the data in purple. In dark blue is a traditional diaphragm regulator.

tony1

When it comes down to it, does 1psi matter?

Synapse

Probably not at 900 RPM when there are 60 injector openings per second, but it may have a more significant impact at higher RPMs, say 8000, when they are firing at 480 times per second, the available mean psi may be different from injector to injector.

It all comes down to reducing noise in the fuel rail. It is important enough that OEMs spend money to put a damper on the rail.