Early model fuel pump upgrade options

[E30-Ellerman]

I apologize for posting this but I haven't been able to find a straight answer.

Basically, just in the process of building my turbo e30 (m20b25) and it's an early model car with the dual fuel pump setup.

I'm trying to do everything the right way for reliability, longevity and good power and along with that would be my fuel issue. I'm not sure if I am able to just dump in a walboro 255 fuel pump in the tank and away I go or what I need to do to get a larger fuel pump in there. Aim is to start at about 10psi and go up from there. I have ARP head studs, new head gasket and will be running an h1c turbo with megasquirt plug n play standalone.

Also, I've read here that the early model setup is actually a bit more reliable than the later model and that people have ran up to 14 psi on the stock pumps without issues... Anyone with first hand experience with boosted early model's, would really appreciate any assistance.

Thank you kindly

[Kepes]

I'm building an M20 turbo to run around 15psi in a PFL setup.
I'm going to keep the stock in tank pump and replace the external pump with a Bosch 044.

This setup is easy and more than enough provided your transfer/in-tank pump is functional. This may not be the best way but from my research it will work well.

[E30-Ellerman]

That is exactly where I want to be at for boost.

Thank you!! I'll likely do the same as you.

[e30davie]

Just have to make sure that the internal pump has high enough flow to keep up with the chosen external pump (044 in this case). Probably will, but you dont to starve your bosch 044.

Last time i designed a fuel sysetm for a ca18det ae86, we had a high flow intank lift pump (pierbirg i think the brand was) and then a bosch 044 external pump. the pierbirg supplied more flow than the bosch but at a lower pressure. The bosch pumps really do not like sucking fuel, they love pressure at their inlet, this will keep them silent (or close to) during operation. I ran a bosch external pump without a lift pump for a while and it did not like it, very noisy.

[gotaloveRWD]

I'm running a walbro 255 in tank and bosch 044 external
i hope they will function well together

[E30-Ellerman]

I'm running a walbro 255 in tank and bosch 044 external
i hope they will function well together

Post up results, thinking I'll need to upgrade my pumps!

Thanks

[SLEEPYDUB]

Im going to try to fit a Walbro 450 in the tank. Wish me luck, because its going to be nearly impossible

[E30-Ellerman]

Im going to try to fit a Walbro 450 in the tank. Wish me luck, because its going to be nearly impossible

Haha. I'm doing a 300lph Bosch in line pump. Hoping it will work ok. Changing the pump in the tank is pricey and I'm not wanting to go through converting to a single fuel pump... yet.

[Good & Tight]

Haha. I'm doing a 300lph Bosch in line pump. Hoping it will work ok. Changing the pump in the tank is pricey and I'm not wanting to go through converting to a single fuel pump... yet.

It will work. Just make sure you purchase an authentic 044 pump and not the cheaper knock off ones.

Adding an adjustable fuel pressure regulator would make a big difference also.

[SLEEPYDUB]

Walbro 450 fits in tank with slight modification. One pump to rule them all. Just run 3/8ths fuel line and you're good for as much power as you want really

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[m3boost]

Walbro 450 fits in tank with slight modification. One pump to rule them all. Just run 3/8ths fuel line and you're good for as much power as you want really

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Do you have pics of the modification required? I remember replacing the oem intank with a 255 and it was atight fit...But I'll be going the e85 route in the near future and would like to use a 450 fuel pump

[LowR3V'in]

is the 450 any louder than the 255?

[SLEEPYDUB]

Do you have pics of the modification required? I remember replacing the oem intank with a 255 and it was atight fit...But I'll be going the e85 route in the near future and would like to use a 450 fuel pump

This should give you a rough idea

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[SLEEPYDUB]

is the 450 any louder than the 255?

No it's super quiet

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[E30-Ellerman]

Just thought I'd update my personal experience post keeping the stock in tank pump and changing the inline pump to the 300lph Bosch set up.

Have been running 11psi boost for about 500 miles on the set up and no issues at all. Getting a dyno tune on May 5th so should get a better idea of how the fuel pump is working but I don't expect any issues at all. Changing the inline pump to a bigger one was a simple and seems to be an effective way to solve any issues or concerns regarding the dual pump set up.