Fuel Pump Voltage increase methods
 

Anyone out there tried increasing the voltage to the stock pump to increase PSI delivered?:vash:

Better off just dropping in a 190lph HP for $80

Thanks. Where can you get that price?

Thanks again!

Just to be clear, what is the standard pressure this HP pump delivers, 5 Bar? vs the 3 bar of the stock pump?

The pump is not set to deliver any specific pressure, that is set by the fuel pressure regulator.

Basically, the capacity of a pump is measured in terms of volumes vs. pressure. A larger pump can deliver either a larger volume of fuel at the same pressure, or the same volume of fuel at a higher pressure (or both, along a finite continuum.) So as the FPR calls for more pressure, the pump is able to keep up with demand.

For example, here is the plot from a Walbro 155:
http://www.rev2red.com/images/cars/faq/155lph.jpg

And here's the plot from a 190HP:
http://www.rev2red.com/images/cars/faq/hp190lph.jpg

(Source and credit: https://www.miataturbo.net/forum/showthread.php?t=4288)

So looks like I'll still need to mess with the stock regulator to consistantly hold a higher pressure under boost. I have full ECU control, and trying to make a "cheap" but reliable road racing set up. Weighing the cost of larger injectors vs fuel pressure increase methods with the stock 230cc injectors. Boost is limited to 6 psi, 7200RPM rev limit.

If your stock pump is in good shape and those are your goals, just add a cheap Vortec AFPR and cause your stock pump to rise to 78~80 psi and handle your needs. You can pick them up for around $50 used.

Any known reliability problems with those Vortec units?

I've used them for years on several applications and have had good luck with them.

I have a vortech for sale 40 shipped sorry for the threadjack

AFPR setup might not be so reliable if WOT is maintained for long periods of time. Specially since you're adding an additional mechanical component in the loop, plus the injectors, fittings, lines, and clamps are under higher continuous pressure than they were designed for. Better option is to get larger injectors since you already have an ECU. Is this a MAF or a speed-density based ECU?

I use a 110v inverter, got it for $25 at walmart, works great

No wonder you're throwing down 20g's!!!

ECU runs off a MAP
 

Using a 2 bar sensor.

here are some photos
 

Here are a few pics of the build.

I find myself salivating, yet I'm not looking at a reese's peanut butter cup.

Run a fused gauge 10 wire from the alternator to a relay on the fuel pump. May get you enough if it's marginal.

engine bay looks great man

Nice Cat

Thanks.

dude do it properly ! dont cheap out now ! and where are your rad fans ?

thats looks neat ! post more pics

If I am seeing correctly, you have the heater core going to the top of the radiator, but no reroute done from the back of the head. When your t/stat opens, you may have no cooling at the back of the engine.

looks to me like he's coming off the engine in both spots...filler cap over manifold.

Yes the back engine outlet is routed over the top of the engine for quick bleed, and 100% return to the radiator. We don't plan on running a fan as this is a dedicated track car, so will sacrifice ease of use for weight loss.
Nobody likes the carbon fiber door inserts?

dude get a set of 550 or beter off ebay spend 15 bucks apeice to have witchhunter clean them and be done with it. You went to all the trouble and work on the car it deserves the biggest injector u can run. The stock pump can handle close to 300 hp at stock pressures with bigger injectors. And run a fan man unless it is a dragster you will want one.

So if you have a tstat in the front, when it opens your flow from the back will be greatly reduced just when you need it. If you don't have a tstat in front, you will never have good flow to the back since the pressure at the front and back will be about equal.

A fan doesn't weigh nearly as much as the water in the bigger radiator.

Appreciate the input. The car is a prototype for converting a spec miata to a reasonably inexpensive Turbo "Super Spec" Miata, with boost limited to 8PSI at the intake, mostly for longevity and keeping costs down. We are hoping by limiting the boost, we can keep more OEM 1.6 parts, so the "kit" will be cheap and quick install. The Turbo and mani are Greddy, with no boost control.
Intake will have sealed relief valve, which will be exchangable ( ie at each race you reach into a box and get your marked race valve just before grid, and return it after the race). So putting pinholes in the waste gate actuator, or messing with the rod etc will not be an advantage. ECU will be open code, but winners of each race will have their files downloaded for posting on the series website. (Braineack- want to host?) So feel free to pass on any thoughts/experiences etc. This forum rules!

The H2O temp sensor at the back of the engine, combined with data from a Pi sensor placed in the front Tstat housing has shown even temps under race conditions with a 190 thermostat in place.

It should be even until the tstat opens. At that point you could drop the flow to the back of the engine drastically.