WALBRO 525 LIMITS

[Chuck Leeper]

The chart clearly shows the effects that a 35 yo electric system could have on the pump's ability to produce the expected results.
I wonder how many engine failures are prompted by having the system to cover the fuel requirements, only to fail from low voltage.

 

[Mr.Spool]

Dont forget about the stock lines and fuel rail

 

[Mr.Spool]

Inmo so many engines were lost due to the fuel/electrical sytem and tune.

 

[TType85]

Dont forget about the stock lines and fuel rail

At what point does the stock fuel rail become an issue? I've been told by may gurus that it is good down in to the 9s no problem.

 

[TType85]

The chart clearly shows the effects that a 35 yo electric system could have on the pump's ability to produce the expected results.
I wonder how many engine failures are prompted by having the system to cover the fuel requirements, only to fail from low voltage.

Anyone trying to run anything but bone stock shouldn't be running on the stock wiring. For my dual 340 setup I ran all new 10ga powers and grounds; I also made sure to use metri-pack 630 connectors to make sure I don't melt something if the pumps pull their max amps.

 

[Mr.Spool]

At what point does the stock fuel rail become an issue? I've been told by may gurus that it is good down in to the 9s no problem.

On e85 I was smart enough to duel feed the rail and revamp the entire fuel system to give it the best chance of living
These stock parts are very old now and if things sit there will be all kinds of problems
Unfortunately going fast now will have its costs which are much higher than years before.
I don't believe on playing hard on alchohol based fuels anymore.
I felt pump gas alky was the best bang for the buck out there and still is if your stock fuel system is good.
But........
Add old parts,none of which is designed for alcohol
And try to squeeze it more and
It's really a recipe for alot of $$ and headaches if you dont do things right 1st inmo.
Look ptfe lines/fittings
Brushless spur pump
Duel fed rail
Good injectors
yes it costs, I make my own alot cheaper lol
But e85 is cheap fuel
And these upgrades will allow for long term use with alcohol fuels and you can make a ton of power.
Go cheap you can get a little time but it will catch up to ya
Since a stock rail has been 8s
I dont see why it cannot go 9s on e85 as usually it's around a 30% differential.
But reread my post there is the cheatsheat in it

 

[3.8 LA LEY]

A single 535/525 on e85 would make me a bit nervous if I was trying to push north of 30psi on a built motor. I am currently running a pair of DW 340's and at 75psi of fuel pressure it probably only flows 450lph.

honestly I'm not going to push it past 28-29lbs on E85. I'm on stock internals.

So that's what triggered this whole thing, I'm right on the line of making it with a 525 or going with the dual 340's.

 

[Mr.Spool]

honestly I'm not going to push it past 28-29lbs on E85. I'm on stock internals.

So that's what triggered this whole thing, I'm right on the line of making it with a 525 or going with the dual 340's.

A good rule of thumb is to get the job done on a duty cycle no greater than 80%
This way there is a 20% cushion for the real world things that can happen.
And the fact that the spray pattern of the injector can be negatively effected.

 

[BEATAV8]

The new ECU’s (ECUGN in particular) offer some very helpful safety / engine protection features which can save your butt. AFR safety shutdown and fuel pressure safety shutdown are always watching. Overboost protection is another.
These goodies come in handy when a hose pops off or when a dork decides to floor it when the tank is near empty.

 

[BEATAV8]

Twin 525’s in a spectra tank.

 

[3.8 LA LEY]

Twin 525’s in a spectra tank.
View attachment 395338View attachment 395339View attachment 395340sweet looking setup you got

how did the spectra tank fit... I'm probably going to get a new tank while I upgrade the pumps lines etc.

 

[TType85]

how did the spectra tank fit... I'm probably going to get a new tank while I upgrade the pumps lines etc.

If you have a OE stock tank and it is in decent shape DO NOT REPLACE IT. The baffling in the tank is better than any of the stock replacement.

 

[BEATAV8]

how did the spectra tank fit... I'm probably going to get a new tank while I upgrade the pumps lines etc.

It went together with some minor adjustment…. But a good stock original tank is preferred

 

[3.8 LA LEY]

I ended up just ordering dual 340's from racetronix with the upgraded lines too. I figure if I want the headroom to push it later on incase I upgrade the turbo or build the block rather have fuel system done right.

 

[ttypewhite]

Real world data using Racetronix twin Walbro 525 double pumper on VP X85. On a 98 degree humid day i put my car on the dyno for 6 back to back to back hits. My limiting factor on E85 was not the pump or my turbo, it was my injector. I am running a 160lb injector and had a 90% duty cycle at 1015rwhp. If I had 220lb injectors I could see 1,100rwhp with this system and more boost without breaking a sweat. It's the best of both worlds, it has the ability to support high hp applications and fits in the factory gas tank and can take you half way across the world like a stock pump without any noises, fuel controllers etc and still retains the factory gas indicator on your dashboard. This system was built specifically for my car. The testing and R&D going into this with numerous CAD designs and bench tests are extensive.

 

[broke]

Which turbo? What was your supply line size? -8 or -10

 

[ttypewhite]

Which turbo? What was your supply line size? -8 or -10

Respectfully not disclosing my build, just the capabilities/limits of E85 with Twin 525 pumps. The system is run with a #10 feed.

 

[ttypewhite]

Twin 525’s in a spectra tank.

I would very very cautious with using this system with that tank. From the tests we have done, that tank needs to be run over the half way to 3/4 mark. The fish bowl baffle doesn't serve well when the fuel starts moving around. The factory tank with the plastic baffles is the best option. Just food for thought.

 

[BEATAV8]

I've seen the same even with a stock tank too, and even the station wagon tank which is a deep & narrow design. When getting close to 1/2 tank the ECUGN will catch the fuel pressure drop and activate the safety shutdown. Doesn't happen when the tank is full.
I set the fuel pressure safety pretty tight, 0.1 seconds.

 

[Chuck Leeper]

Someone needs to design a dual pick up Hydramat.....
1.Or make a "kit" to remove part of the stock tank top & baffles, and add a replacement top section with a properly designed baffle system...
2. Build a tank to fit the stock location with the proper internals and good access.
It's only money folks!