Called the shop today and they suggested I get your input on the following....



With respect to a stage 1 Evo, 93 octane operating at 600 feet above sea level, do you recommend upgrading the fuel pump (e.g. Walbro 255)?

 

Yes, I'd recommend it. Might not be absolutely necessary until you add cams but doing it a bit earlier is a LOT better than doing it too late.

Shiv

 

One follow up question. Are aware of an alternative pump that makes less noise?

The rubber sleeve seems to make the Walbro assembly too large to fit into the Evo's in tank assembly. Are you guys using the sleeve on your installs?

 

Just one statement. I have installed over 20 walbros in EVOs. They drop right in and fit perfectly. You might be doing somthing wrong or have the wrong pump.

Eric

 

No question w/o the rubber sleeve. With the sleeve the diameter of the pump + sleeve is too large for the tube that the pump resides in. Or am I missing something here?

Maybe there is a thin rubber sleeve that I don't have. Maybe cut it down to fit. Or something....

 

I think Walbo does offer an optional rubbers sleeve to quiet its operation a bit. I can see why it wouldn't fit into the holder when equipped with it. There are other pump options from Denso that may be quieter. But my testing with them is pretty minimal.

Shiv

 

The Sleeve is not needed. The only thing needed is the pump itself. My Walboro is absolutely silent.

 

I wish I could say the same for the unit I have in hand.

It isn't clear why some people say that their pump cannot be heard. The few vendors / installers I have talked to agreed that out of the tank all of the units sound the same. There is only one way to install the pump, hence this shouldn't be the difference.

It is notable that when the pump runs without a load it makes much less noise. As the pressure in the line builds, so does the pump's noise output. The large difference in the noise output between unloaded and loaded is very dramatic!

This said, I'm at a loss on this one. I have thought about picking up a second pump in the hope of finding something different, but I expect that this is just a waste of money.

 

Further to the last post....

I picked up a PE210 but it was received the outlet nipple broken off. The PE210 is a Denso look alike from a company that on paper doesn't appear to have anything to do with Denso. Maybe they purchased the rights to the design. If not they ripped it off.

The older PE210's appear to have been sourced from Denso, but I have been unable to get a Denso part number for their higher output pumps that are form factor compatible with the Evo.

 

I have heard a sound clip of a loud Walboro and it was really loud. What scares me the most is the only thing in those things is an electric motor with some gears. That sound is the electric motor bearings in my opinion. If the sound was gear related then everybodies Walboro would make that "jet engine" sound. IMHO if my pump started making that noise then I would replace it. I just can't believe that some people call this sound normal.

 

I wonder if people might be over-torqueing the cover back on the tank? That might transmit some extra noise into the body or cabin. I haven't been able to hear my pump above the exhaust yet, but I guess we'll see in a few months.

 

My walbro is almost as quiet as the stock pump 99% of the time.

But on a few occassions it has gotten really loud. Pretty scary. Quite a few people also have the same issue so I don't think there's anything wrong with the pump. But it sure does make you wonder.

 

I cant hear mine AT ALL....... if it is too loud for ya just get a 3" exhaust - that should take care of the noise (you are sure not to hear the pump with an exhaust!)

 

I have the walbro pump installed on my Evo. It is much louder than stock, but only after i have been getting "on it". It whines when you have been racing around or stepping on it....and it's okay. If you have been racing around and your walboro pump is not making a noise...then you might want to have it checked. All the people I have spoken to say that the noise it makes when it is really running good....(the loud whine)...is normal and that is a sure fire way to know that your pump is working correctly.

If I am just driving normally and not fast at all, then my pump is pretty quiet.

Just my .02 cents

Smokey

 

Attached is a zip file containing a mp3 of the Walbro pump running on the bench. Notable is the initial sound when the pump is priming. This is what you hear when the key is first turned on. When partial pressure is present the sound stabilizes and goes up in intensity as the line pressure comes up.