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2G Walbro 450 Install

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I had to chop off the "bell" on the pick up tube that normally our pumps slide up into, then I just hose clamped the hose to the pump and the modified pick up tube.

That may work on a 1g, but on a 2g there is not much there to work with. You have to drill it out and install a bulkhead fitting.

Will this cover not pop off to expose two screws??? I don't run a 450, I have a Stealth 340 so I haven't seen one up and personal is why I ask.

I dont think that comes off. The best way is to cut off the connector and just use the supplied butt connectors.

Few questions, what part is the "fuel stock" you're referring to? I posted a pic of my kit and it only comes with some clamps, butt connectors, and a rubber hose.

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this is the sock / strainer that I am referring to.


Worst case scenario you could use your old one until you get one of these. Im not sure how much of a difference it makes, but there is a significant size difference and im sure the smaller one is somewhat restrictive.


The nipple you're referring to, is it the one that has the o-rings and inserts into that tube looking thing at the top?

Yes, the ones on the top of the pump. Like I said, with the bigger sock and the bulkhead fitting I had to cut one or two of the nipples off for some clearance.

And also, I've read it's always good to do the siphon mod so I was going to do that. I believe it's supposed to be drilled to a 1/8" hole.

This is correct. Do not drill it out any bigger or you will mess up the venturi effect.

If you really wanted to get it done tomorrow, you could try to use the toyota seal on the fuel pump and use the stock fuel tube. No guarantees it will seal though and may only work temporarily. Some people have luck with it. The bulkhead is the proper way though IMO.

If you re use the smaller sock / strainer that is on your current pump, you should be able to get it to work. Depending on the fuel type / amount of fuel needed, you will have to more than likely do all of the above things. For a car that does not need a bunch of fuel, you could probably do without the upgraded fuel lines and the larger strainer. I however am on E85 and 33psi of boost (which I forgot to mention) so I need to flow more volume.
 
That may work on a 1g, but on a 2g there is not much there to work with. You have to drill it out and install a bulkhead fitting.



I dont think that comes off. The best way is to cut off the connector and just use the supplied butt connectors.


this is the sock / strainer that I am referring to.


Worst case scenario you could use your old one until you get one of these. Im not sure how much of a difference it makes, but there is a significant size difference and im sure the smaller one is somewhat restrictive.




Yes, the ones on the top of the pump. Like I said, with the bigger sock and the bulkhead fitting I had to cut one or two of the nipples off for some clearance.



This is correct. Do not drill it out any bigger or you will mess up the venturi effect.

If you really wanted to get it done tomorrow, you could try to use the toyota seal on the fuel pump and use the stock fuel tube. No guarantees it will seal though and may only work temporarily. Some people have luck with it. The bulkhead is the proper way though IMO.

If you re use the smaller sock / strainer that is on your current pump, you should be able to get it to work. Depending on the fuel type / amount of fuel needed, you will have to more than likely do all of the above things. For a car that does not need a bunch of fuel, you could probably do without the upgraded fuel lines and the larger strainer. I however am on E85 and 33psi of boost (which I forgot to mention) so I need to flow more volume.

I actually do have the larger sock that it comes with, sorry I was a little confused at first. My future goal is to run e85 but for now I don't think I need to upgrade my lines as I am just gonna be using pump gas.

My biggest concern now is getting that little nozzle on the top to seal. I really hope I don't have any problems as I don't have a bulkhead.
 
Anyone know what wire goes to what wire? I'm assuming the red one on the 450 goes to the very dark blue wire that is on the stock connector on the assembly and the black one goes to the black wire on the assembly
 
Anyone know what wire goes to what wire? I'm assuming the red one on the 450 goes to the very dark blue wire that is on the stock connector on the assembly and the black one goes to the black wire on the assembly

Yes
 
Well I just did the install and checked to verify no leaks and such. Set base fuel pressure was to 43.5 psi with the vac line capped. Then when I hooked it to my afpr, it hardly went down. At idle my car is at like 41 psi or so. Is this normal? This is with the line attached.
 
I notice that your previous question wasn't answered about pressure drop. Your psi should go down with vacuum applied and go up when boost is applied. Surely your engine has more than 2-3hg of vacuum so your pressure should drop more when you put your vacuum hose on. I just went out and pulled the line off of mine and I go from 43.5 down to 35.5 with the vacuum line on it. This is on my bone stock 92 Talon.
 
I notice that your previous question wasn't answered about pressure drop. Your psi should go down with vacuum applied and go up when boost is applied. Surely your engine has more than 2-3hg of vacuum so your pressure should drop more when you put your vacuum hose on. I just went out and pulled the line off of mine and I go from 43.5 down to 35.5 with the vacuum line on it. This is on my bone stock 92 Talon.
I was told my pressure drop was normal because of the Walbro 450 being the high pressure pump that it is. Either way, I still do think it should have went down more than it did. This is why I'm back on this thread. I'm pretty sure my o-ring is the issue.
 
Yeah I reviewed that thread and just replied to it.
If the regulator doesn't knock the pressure down, its gonna over fuel it and wash cylinder walls.
Maybe a 450 keeps pressure up but my 340 and 255 never did, they dropped proportionally with vacuum and raised appropriatly with boost.
 
This could maybe be the reason for my startup problems as well probably. Well I just ordered the Toyota seal and it should be here Wednesday. I HATE having to remove the fuel pump assembly but I hate having to hate my car for doing this even more LOL. Currently, I cannot get the car to start and I'm at work. FML..
 
Well crap, I already ordered the other one from the local Toyota dealership for only $2 and some change. I feel like maybe I should just try that. $8 is kind of a lot plus shipping..

Well they look almost exactly the same so I guess we'll see.
 
Are you using both seals? Take a picture of it before you install it onto the car.
No I am not. I just used my old o-ring that was on my stock fuel pump and then another o-ring I bought just in case one wasn't enough. I am pretty sure it slid down while I did a WOT pull and now it's leaking because the car won't even start.
I will be sure to take a pic before installing.
 
Ok let’s take it from the top...
I just read every post and I’m more confused now than when I started...
For now I don’t intend to upgrade my feed or return lines nor do I want to go down the bulkhead road, if I require more fuel than what stock lines can supply with this pump then I'll go down that road.

So as I understand it based on the install kit available now (2019):
Vehicle Wiring:
1. Fuel Pump rewire with heavier gage wire for constant voltage is required
Pump Wiring:
1. Remove the wiring from the hanger assembly
2. de-pin the connector circled in Red
3. Crimp Molex connectors to new pigtail from install kit circled in blue
4. Insert new pigtail into the terminal circled in Red removed from original wiring
5. pump is now a plug and play (from the wiring standpoint) and sealed for safely running e85

Mechanical:
1. Blue Circle - The orange cap, o-ring, and spacer from original pump (if OEM) No longer used
2. Red Circle - shave down the rubber insulator as the 450 is taller and won't fit without modification - bolt hole may need moved or elongated
3. Green Circle - when the protective cap is removed you should cut off the 2 barbed nubs so that the tube is similar in height to the original.
3a. Use Toyota/EVO O-ring/Seal; Toyota Part#: 23239-21010 or Mitsu Part#: MR431121
3a1. Only this seal will be used on nipple in the green circle when installing back into the housing?
4. Yellow Circle - This is the big sock included with the install kit; use it
5. drill out the syphon hole NO LARGER than 1/8 (sorry no picture)

If anyone can either confirm that this is correct or help me to fill in the blanks I would greatly appreciate, I need to see everything in a consolidated way like this to really wrap my head around it.

Thanks!!
 

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Ok let’s take it from the top...

Something you could think about if you already have a Walbro 255 intank working properly. Just leave that in there and add a Walbro 255 inline in series with the intank. It solves the problem of rapid flow dropoff at high pressures. Optionally you can put the inline pump on a boost pressure activated relay which leaves it unpowered until you are in boost. That way your fuel flow at idle and low load will be nice and low, which is nice. My car is done that way and I like it. Flow rate is high at high pressures (where you need it) - higher than a Walbro 450, I think, haven't looked at this for a while. You would need a place on your firewall or someplace to put the inline. Mine is on the firewall. (1g, flex fuel)

Red line on the chart below is this system:

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Thank you for the alternate solution. I’ll keep this in mind if I’m unhappy with the 450. For now though I don’t have a 250 and I’ve long since blown my build budget LOL so I’ll keep pushing forward with the 450 for now.

1st thing I’ll correct from my post above is that based on what comes in the install kit you actually need to cut the black connector circles in green off and re-pin that with the included female connector to mate with the connector on the pump.
 

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Ahh, another member of the Blown Budget Club. Welcome!
Lol yeah, like most DSMs it’s a long story. Short version... I had a built GST and it’s been sitting for a few years. I decided to get it back on the road and it’s rusted out. So I picked up an AWD TSI that I could just swap all my “good stuff” over to and be running in a month... that was January... my wife is supportive but she has her limits and I found those last weekend
 
Lol yeah, like most DSMs it’s a long story. Short version... I had a built GST and it’s been sitting for a few years. I decided to get it back on the road and it’s rusted out. So I picked up an AWD TSI that I could just swap all my “good stuff” over to and be running in a month... that was January... my wife is supportive but she has her limits and I found those last weekend

Ok that made me laugh. I've been single for 20 years so I can do almost any thing I want no matter how stupid ! LOL

Seriously I have a lot of fun with this hobby. It just ends up costing a lot. I take comfort that there are crazier than me. One neighbor here had his 300ZX in a shop for 4 years. It's 100% beautiful. Another neighbor has bought a kei truck and a kei car, now wants to buy a kei van! A third one here bought a JDM R32 Skyline because his modified Subaru wasn't enough I guess. These are not rich guys, just "regular".
 
Ok that made me laugh. I've been single for 20 years so I can do almost any thing I want no matter how stupid ! LOL

Seriously I have a lot of fun with this hobby. It just ends up costing a lot. I take comfort that there are crazier than me. One neighbor here had his 300ZX in a shop for 4 years. It's 100% beautiful. Another neighbor has bought a kei truck and a kei car, now wants to buy a kei van! A third one here bought a JDM R32 Skyline because his modified Subaru wasn't enough I guess. These are not rich guys, just "regular".
Ha ha! If I wasn’t married I’d be in trouble. She keeps me grounded. But she is good to me, we have 3 kids in car seats and I drive a corvette. The only thing she said when I bought it was “Why don’t you get a new one?”
 
Ha ha! If I wasn’t married I’d be in trouble. She keeps me grounded. But she is good to me, we have 3 kids in car seats and I drive a corvette. The only thing she said when I bought it was “Why don’t you get a new one?”

That sounds pretty good!

Hope your 450 install goes well. I can't answer your questions in post 67 but I hope somebody does!
When I installed my in-tank Walbro 255 I took one look at the o-ring plus spacer arrangement on the outlet and it made me so pissed I just stopped right there to figure out a different way. I bought one foot of soft Viton rubber tubing, cut off a piece 15/16" long, and used that instead of an o-ring plus spacer. It was soft, durometer 60, Shore A scale. There was no like fabric in it. Just rubber. 1/4 inch ID, 9/16 inch OD, 5/32 inch wall thickness.
That was in 2009. I can't find that stuff now unless maybe you want to buy about $1000 worth of it. I got it in 1 foot lengths at the time from "Small Parts" which was a great place. They later became a "store" within Amazon and didn't have that tubing anymore, and I've never found it anywhere since.
 
Small update, I haven’t spent much time on it but the 2-3mins I had when the Evo o-ring arrived has me convinced of you get this seated it will absolutely seal, getting it seated properly is going to be a chore though. Hopefully I’ll get out there and get it done this weekend.
 
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