I am thinking of this as a secondary external pump, and use a regulator with a return to the drivers side saddle tank.

The summit page shows 45 PSI max, but the Aeromotive spec page shows 70PSI (at 220 lph)

 

So I have a question...

If a turbocharged RX8 pushing north of 380whp is able to do so with a single upgraded walbro fuel pump why are there people thinking they need a pump booster or a second fuel pump?

Get the high pressure walbro and be done with it.

 

A single upgraded fuel pump running at max capacity.



We want a real fuel system....

 

Interesting because this same RX8 was showing 60 psi across the board. A fuel system that is maxed out would show signs of fuel pressure dropping in boost.

How many of you guys are running fuel pressure gauges?

 

just to put this out there..

anyone know of an upgraded pump for the 09? i have a 09 pump and have some testing in my future????

and yes, that was aimed at you denny!

beers

 

Been really busy. Have a lot more info to post. But first I need to crack open the fuel filter housing and get some pictures. More to come!

Oh, and some pictures of the frankenstein fuel filter setup to drive the car home from Road America.

 

swoope i am going to upgrade the pump by installing a kenne bell bap--justs makes sense to me. Gives me a lot more control if needed. the denso pump is ok to 17volts.
OD,

 

Which is only a 20% voltage increase - good for about 15 additional liters out of the OE pump.
Of course, because of the failure modes encountered in this pump, you will get no gain (or even a greater loss) on a failing pump and no noticeable increase in output because of the design of the bypass.

 

Let's also not forget that the boost a pump will cost as much as at least 2 of these pumps and do 1/4 of the job. I fail to see how one group of people pushing approx 300 whp are having fuel starvation issues while there are various RX8's out there pushing north of 330whp that have none of these fueling issues.

This isn't a hard subject. The left hand fuel starvation issue is due to there being no fuel brought over from the right tank. This pump will allow that fuel to be brought over thereby eliminating that issue. It provides more than enough pressure to fuel the car till probably about 500 crank horsepower.

What makes sense to me is spending $90 on a pump, making a simple 5 minute modification to the fuel pump assembly and dropping it back in the car. Mazdamaniac has done this twice now in my car and if we spent an hour doing them combined it was cause drinking was involved.

 

I have a new stock pump assembly en route. Due to some of the failures I've experienced the 4 days over the weekend, I'm going to test the new stock unit to see if I get the same problems under the same conditions.

My fuel cut outs, rough conclusion from all the testing and everything else, lead me and 2 other people to the conclusion that the filter element itself in the housings I was using were actually collapsing and blocking fuel flow. Even a fram filter from Fleet Farm (only thing available on a sunday when you need to drive 3.5 hours home from the track) did the exact same thing. So once the new OE unit comes and I can pull frankenfilter out I will cut up my old stuff and post up the results.

 

Why don't you believe it's the pump

 

nothing wrong with a bigger pump. Swoope just asked what my plans were.
I like the control the bap it gives, the fact that it also acts as a fp voltage regulator (just a 5psi drop in pressure will lean out your mix 4%) as voltage has been known to drop when a lot of accessories get turned on. Maybe just a split second but they do.
I like that it is a stepper motor system so to speak and not just low and high as with the small injectors we run accurate pressure is critical. Plus it is not circulating a bunch of fuel all the time. It can heat up a little?
flow tests results are impressive
on a stock mustang GT 4.6 liter single pump at 13 volts and 60psi flowed 115 liters per hr
with the bap at 17.5 volts it was 201.
the walbro gss 342 at 13 volts and 60lbs was 192 lph with the bap added and at 17.5 volts it was 274lph.
Besides yall know i am trying to turn this thing into a mustang.
OD

 

So are you planning on running lots of accessories when your boosting the car? Running the AC on the track? If a 4% adjustment in either direction is so critical you need unwaivering pump voltage then I would argue you are tuned too close to the edge.

What can heat up? The pump? The walbro upgrade has been shown to run constant pressures regardless of load or RPM. The pump only runs in a low mode to reduce noise otherwise it can run on high the entire time without overheating.

I'm not arguing the boost a pump increases flow. I just don't understand the logic in spending more to stress a part that already is prone to failure.

So here's my question. Why would you spend $200 on something that stresses a part that is already prone to failure which will also require additional wiring and installation and not fix the problem?

It's really simple. The walbro can be had for $90. It drops right into the stock pump assembly and you simply modify the siphon tube to make sure the pressure relief doesn't shoot off. Then you're done! You have plenty of fuel and shouldn't have any left hand stavation issues.

I'm not trying to bust your ***** Denny, I'm just having a hard time understanding why you want to spend more money for less stuff and end up with a pump failure sooner than before. It's cheap, easy and fast installation. Rarely does any part do that.

 

Good thing that's not true or we would be in a HEAP of trouble.

 

I know guys and no offense taken on this end at all. Nothing wrong with a bigger pump--nothing at all. Its a good option and its great yall discovered that it is a drop in thing. Kudos.
Yes I have been known to go into boost with all the acessorys on. And I (and others!) have been know to forget to turn the a/c off when we get on track after setting on grid for a while in the heat! Lol. That was funnyand stupid
Its just something I prefer to do. Like doing the 09 swap. i really havent had any of the classic track starvation issues since I did that. As long as the gas line is on tight
I have noticed that with some subtained high rpm there is a slight change in the a/f's that may suggest that the pump is having to strain. Nothing in the Uh-Oh range but none the less I will not ignore it.
I like the 09 assembly, yall know that by now and I dont think the walbro will fit that one anyway?
olddragger

 

When you go 429, see Dyers for a blower.....

OMG, 429/8-71 in an 8?

 

BUMP!

New info in OP.

 

You can't do that.
You MUST have this pressure release assembly or you will swamp the regulator and empty the fuel bowl.

The modification I talk about in my thread is to permanently attach the top cover, not replace/remove the pop-off.

By closing this opening, you have turned your siphon back into a pump, which will drain all of the fuel FORCIBLY back into the tank.

 

I realized that after reading your PM. I'm will note that in my OP

 

Sorry!
I realized my write-up might have been a bit vague in explaining what I was doing with the siphon cap.

 

NP. I just bought some extra parts and went ahead modding it without giving it a second thought or trying to contact you for specifics.

Lesson learned. Now I just hope that there wasn't any damage done to the walbro....

I am still going to pull apart the filter basket. Still curious to see whats inside and if I did indeed collapse it. Didn't get to it on sunday as planned as the weather was so nice.

 

Not likely. She's a tough little b*tch.

I've never seen one collapse, but I've only taken apart a dozen or so bad pump assemblies, so its always possible I guess.
However, even if it totally imploded, the cartridge is setup in such a way that most of the fuel will bypass it anyway.
You'll understand when you get it open.

 

subscribed for the future.

 

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