Skip to content
View in the app

A better way to browse. Learn more.

Ultimate Subaru Message Board

A full-screen app on your home screen with push notifications, badges and more.

To install this app on iOS and iPadOS
  1. Tap the Share icon in Safari
  2. Scroll the menu and tap Add to Home Screen.
  3. Tap Add in the top-right corner.
To install this app on Android
  1. Tap the 3-dot menu (⋮) in the top-right corner of the browser.
  2. Tap Add to Home screen or Install app.
  3. Confirm by tapping Install.

Ej swap, Fuel starvation?

Featured Replies

So someone said that there are problems with the stock fuel tank and fuel starvation in the older Subarus when you do an Ej swap.

 

Is that true????

In my 87, as long as you keep it above 1/3 of a tank, it's fine. But, as it gets lower, it will suck air and sputter when stopping or turning. The lower the fuel, the worse it gets. But, mine was carburated, so I suspect the fuel injected models had better baffles in the tank.

  • Author

Well my Brat has the 2.2T but I haven't gotten to the point to finish the swap. It has the stock fuel tank so any info from anyone would be great.

Plus I have an 88 Rx that I plan in the future to put in a 2.2 N.A. and want to make I don't have any issue.

 

Feedback please. What was your 87???

He said his was carbureted, so it has to be a 4wd model. The carb cars don't have the baffling in the tanks like the efi models do.

 

You should be good on the RX, but for the brat I would search out an 83/84 ea81t tank or invest in a surge tank.

I have an EJ swapped '83 GL Wagon. I have been driving it on and off for almost 10 years without any problems. I don't let it get really low on gas though.

Mine is an 87 GL Coupe, EA82. It was a push-button 4wd with the 3eat when I got it, but I swapped it to a dual-range 5-speed.

Get the appropriate fuel tank from any fuel injected Subaru (An EA81T, in the case of your BRAT) and be done.

 

A surge tank is used when the OEM fuel tank is not baffled.  It is essentially a mini fuel tank that is so small that fuel can't slosh away from the pickup.


On a turbocharged car it is VERY IMPORTANT TO AVOID HIGH-LOAD/HIGH-BOOST FUEL STARVATION (aka RUNNING LEAN).

  • 2 weeks later...
  • Author

Anybody have a link of a diagram of a surge tank so I know I am doing this right? 

This was about the 5th result for a google image search for "surge tank"...

Surge%20Tank.gif

 

I probably won't bother when/if I put the EJ18 in my Brat, but it won't be turbo, so it's not the end of the world if it starves occasionally. If it becomes a considerable problem, I may re-evaluate...

 

 

 

FWIW, I never had an issue with the EJ22-swapped '86 wagon (originally carbed). I'm under the impression that it was only the EA81 tanks that didn't have the proper baffling....but I've never had either apart.

Edited by Numbchux

I can tell you my experience with the ej swap in my girlfriends 86 GL. Hers was an ea82 carbureted model. I was reading in numbchux's write up that it is only the ea81 models that experience this type of fuel starvation.

I can tell you after nearly 2000 miles on the swap, that we have not experienced these issues, and we have run the tank down to almost empty. It does have a monster fuel pump installed, but I think as long as there is sufficient pressure you should be ok. 

One critical piece of advice that I learned from GeneralDisorder is that you have to switch the return and vent lines at the front of the tank, otherwise gravity will cause fuel to flow back through the vent line and come out of the evap canister, which will result in the engine getting flooded and stalling.

Other than that, all the fuel lines are factory size and location, including the steel lines and the ones coming out of the firewall.

Happy wrenching!

  • Author

Do you have a diagram that I can reference???? If it came from GD, I am sure he is right. He knows his stuff. 

 

I'm at that point to be hooking up the new fuel pump and lines and want to make sure I have them right. 

 

So at the 2.2T engine there is 3 lines on the motor, and I have the 3 on the firewall. 

 

I think it is fuel supply and return up in the corner, with the vapor to the left of the master cylinder.

If anybody knows for sure please chime in. Thx.

Edited by Naked Buell

As GD used to say "the search button is your best friend" or something like that. A quick search produced these.

 http://www.superstreetonline.com/how-to/engine/ssts-1119-building-a-fuel-surge-tank/

     

 http://www.datsun-france.com/Ratdat/ratdatblog/?p=168

       

http://madscientistmatt.blogspot.com/2005/12/surge-overkill.html 

 

The options are build a surge tank or find a tank from an FI car or keep the tank above 1/4 filled.

 

The tank for your RX should be fairly easy to find but for the Brat you need one from a turbo car ( Brat, wagon or coupe ) it doesn't matter.

Edited by silverhelme

Please sign in to comment

You will be able to leave a comment after signing in

Sign In Now

Account

Navigation

Search

Search

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.