Walbro 400LPH intank pump ? Anyone got any info
Isn't a single fuel pump inherently safer than having to run two? You have a single point of failure versus three (2 pumps + hobbs switch). If a single pump fails, you go into a lean condition much like fuel cut, it causes no damage to the engine and it shuts down. Say you now have a double pumper setup with a hobbs pressure switch that fails in the middle of a drag run, now depending on how much of that second pump you rely upon for fuel, your AF ratio may lean out 1-2 points (say from 12.0 to 13.5) and knock the living hell out of your motor all the while boosting 30-40psi. I know there are fail safes in place for these kinds of things, but how many people really use them and test them to make sure they work properly?
If I had a high power car and was able to get by with running one pump versus two, I certainly would take that route.
If I had a high power car and was able to get by with running one pump versus two, I certainly would take that route.
The height of the unit has already been discussed in this thread. In the other thread there was no actual running of the car or testing, just "Grind this and put it in, more grinding may be required" The MORE GRINDING part is what I found measuring the two pumps and the stock unit and is why I thought you'd up up cutting into the actual filter area of the assembly, making it pointless to do it. I went over all that. If you took note in the other thread, instead of just typing crap about ME, you'd have noticed he said "MORE GRINDING MAY BE REQUIRED" you'd have also notice the final installation pictures APPEARED TO ME that the pump was still up too high and only had ONE NUT holding the assembly in. IF the overall height is too much and you don't get a good seal between the tank/pump assembly, when you fill the car with fuel you will get a severe leak.
When I get a pump back here I'm going to show the measurements to justify my initial thoughts and then try cutting/grinding off enough to make it actually go in and seal.
When I get a pump back here I'm going to show the measurements to justify my initial thoughts and then try cutting/grinding off enough to make it actually go in and seal.
I'd rather spend what it takes for a solid, proven double pumper or other safe option, if there's any question that the new pump is either unsafe because of seal issues, or prone to failure because of the inherent modifications needed to make the pump fit.
Can't wait to find out what people who have the pump and the fuel pump housing learn and post for the rest of us.
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I'm not trying to be the negative Nancy here, but a lot of people are going to end up Effing this up and just causing them to waste more money on getting a new assembly.
I don't have a double pumper setup in my vehicle right now nor do I need one at this time. But in the near future I will. I will NOT be taking any shortcuts by hacking this and this and that just to make a fuel pump fit to only limit myself to around 550-600WHP. I would rather just pay the money to get the job done right the first time and have the headroom to expand if need be.
This is just my personal opinion and I don't need any negative comments, I just don't like taking shortcuts.
I don't have a double pumper setup in my vehicle right now nor do I need one at this time. But in the near future I will. I will NOT be taking any shortcuts by hacking this and this and that just to make a fuel pump fit to only limit myself to around 550-600WHP. I would rather just pay the money to get the job done right the first time and have the headroom to expand if need be.
This is just my personal opinion and I don't need any negative comments, I just don't like taking shortcuts.
We had to cut a little more than what is shown above to get the barb to seal on the top of the pump which also negated the ability to snap on the lower retaining portion, thus we have to clamp the pump in place. We will take another look at it and see if the method above will work, but as with David we have concerns about it sealing at the top and we also feel the overall height would be too long.
I WILL work on this all freaking day tomorrow if the 400 pumps show up, I am going to do my absolute best to not just measure it but to try to physically make it fit in the assembly AND install it in an EVO and see if it runs/holds pressure etc.
IF it fits I apologize for assuming, from measuring and knowing how the stock assembly actually functions (like the fuel filter and fuel pump plug) and thinking it wouldn't work.
There is profit in these pumps for vendors as there is a STRICT minimum price set on them, I have no reason to NOT sell them as they are still not a replacement for a double pumper. If I didn't want to use them I sure as hell wouldn't have paid to have them flowed by an independent company for results and wouldn't have promoted them for the EVOX.
IF it fits I apologize for assuming, from measuring and knowing how the stock assembly actually functions (like the fuel filter and fuel pump plug) and thinking it wouldn't work.
There is profit in these pumps for vendors as there is a STRICT minimum price set on them, I have no reason to NOT sell them as they are still not a replacement for a double pumper. If I didn't want to use them I sure as hell wouldn't have paid to have them flowed by an independent company for results and wouldn't have promoted them for the EVOX.
Isn't a single fuel pump inherently safer than having to run two? You have a single point of failure versus three (2 pumps + hobbs switch). If a single pump fails, you go into a lean condition much like fuel cut, it causes no damage to the engine and it shuts down. Say you now have a double pumper setup with a hobbs pressure switch that fails in the middle of a drag run, now depending on how much of that second pump you rely upon for fuel, your AF ratio may lean out 1-2 points (say from 12.0 to 13.5) and knock the living hell out of your motor all the while boosting 30-40psi. I know there are fail safes in place for these kinds of things, but how many people really use them and test them to make sure they work properly?
If I had a high power car and was able to get by with running one pump versus two, I certainly would take that route.
If I had a high power car and was able to get by with running one pump versus two, I certainly would take that route.
Here is an explanation of the modifications we made to both the pump and housing, our biggest concerns were making sure the pump seals at the top and the overall length is the same as stock. Is a clamp the best way to secure a fuel pump, probably not but its not going anywhere lol. We're certainly open to other ideas so feel free to share your thoughts!
Below is where we cut, as you can see the tabs for the stock retainer will be removed. Be careful not to cut into the fuel pump plug (the black thing with the wire going to it), see below for the final product!
Here is what we ended up with:
Pump installed using filter and wiring harness provided in 400-0001 installation kit along with clamp:
Comparison to stock assembly:
Slight modification to pump outlet to ensure proper length:
Factory seal is still utilized:
Below is where we cut, as you can see the tabs for the stock retainer will be removed. Be careful not to cut into the fuel pump plug (the black thing with the wire going to it), see below for the final product!
Here is what we ended up with:
Pump installed using filter and wiring harness provided in 400-0001 installation kit along with clamp:
Comparison to stock assembly:
Slight modification to pump outlet to ensure proper length:
Factory seal is still utilized:
Last edited by ChrisCarey; Oct 6, 2011 at 09:23 AM.
Very good Chris. See, that is about the measurement I got too, but when I was looking at it I didn't think to try and grind past the fuel pump plug (the black thing with the wire going to it) I only thought to cut it off straight across and if you do that the assembly won't work. It does look like how you did it is what I was going to try and same thing, use a clamp BUT didn't think to grind down past the fuel pump plug leaving it. Actually at a glance the diameter of the 400 pump looked to large to get in there.
What you have there has to work with the extra cut off, that is what I was going to do today when the pumps come in. Looks like a winner.
What you have there has to work with the extra cut off, that is what I was going to do today when the pumps come in. Looks like a winner.
As a side note, I may put one together and send it out to have the actual assembly flowed, my guess is the factory fuel filter and the way it's designed is going to choke that pump WAY down. When I get it together I'll ship mine off for flow testing and report back how it compares to just the pump flowing, I bet it drops 30%.
