TheSamba.com :: View topic - Subaru swap. Why not switch to carburation?

Tue Feb 08, 2022 4:20 pm

I'm still contemplating what direction I want to go with my 1972 bus. The 1.7L maybe savable, but I've been looking at everything from type one conversions to Subaru swaps.
One thing that confuses me is why no one has offered a simple carb swap for the EJ22 or EJ25. It would seem to be an easy way to cram that modern engine in without the need for an ecm. Is it due to the ignition system? I can't recall if they are both run by the same ECM on that car.

Tue Feb 08, 2022 5:49 pm

The ECM runs everything. Don’t fear the ECM, there’s plenty of laptop timers for it. Hang out on some subbie sites, lots you can do with it.

Tue Feb 08, 2022 5:57 pm

Indeed, carbs would be a major downgrade in performance and economy, not to mention all the other things that would have to be modified if you ditched the ECM.

Tue Feb 08, 2022 6:27 pm

The simple reason is that the engine was designed for fuel injection, and many of the benefits you get from a modern engine would be lost if you moved it to carbs.

For instance, you will never get the fuel mileage or clean burn or partial zero emissions running with carbs.

With the stock wire harness being easy to get and aftermarket EFI being so readily available (even for specific Subaru to Bus swaps) its kinda crazy to try an adapt carbs.

Zach

Tue Feb 08, 2022 7:20 pm

busdaddy wrote: Indeed, carbs would be a major downgrade in performance and economy, not to mention all the other things that would have to be modified if you ditched the ECM.

Let alone trying to find someone that would be able to work on it.

Tue Feb 08, 2022 8:47 pm

When I asked my mechanic if he worked in carbs he said he has cut out bagels but still enjoys pizza.

Carbs are done in modern engines

Tue Feb 08, 2022 9:07 pm

Abscate wrote: When I asked my mechanic if he worked in carbs he said he has cut out bagels but still enjoys pizza.

Carbs are done in modern engines

Tue Feb 08, 2022 9:12 pm

TheRustyRabbit wrote:

One thing that confuses me is why no one has offered a simple carb swap for the EJ22 or EJ25. It would seem to be an easy way to cram that modern engine in without the need for an ecm. Is it due to the ignition system? I can't recall if they are both run by the same ECM on that car.

what's to be confused about? by and large carburetors are a pain in the ass.

it has been done. this guy liked the looks of the dual carbs i guess:

but the time spent in working the ignition, plus timing map, plus carb tuning, plus custom intakes is really a step backwards not only financially but time wise.

i couldn't imagine going thru all that work, just to have to try and make it run.

but i guess if you're afraid of ECU's and fuel injection i could see the appeal

Tue Feb 08, 2022 9:29 pm

Carburetors are done,done,done. You fight like hell to keep stock set ups running and starting. Ethanol eats the kits, boils dry in the heat, attracts moisture. And you never really know how much booze is in the stuff you buy. Independent state testing in Colorado found up to 28%. FI cares not and will happily mix about anything that gets past the fuel pump.

Interesting that the carb set up had no belt on it..who knows if it actually ran

Tue Feb 08, 2022 10:49 pm

:lol: :shock: OEM Subaru carb. I think they stopped using those in the U.S. in 1990.

Skills next Subaru conversion on my Rusty 72. :wink:

Wed Feb 09, 2022 2:25 am

There is a crying need for a new Bears video

“ I would like to put a Subaru engine into my VW van….I mean, Bus….”

Wed Feb 09, 2022 7:16 am

skills@eurocarsplus wrote: TheRustyRabbit wrote:

One thing that confuses me is why no one has offered a simple carb swap for the EJ22 or EJ25. It would seem to be an easy way to cram that modern engine in without the need for an ecm. Is it due to the ignition system? I can't recall if they are both run by the same ECM on that car.

what's to be confused about? by and large carburetors are a pain in the ass.

it has been done. this guy liked the looks of the dual carbs i guess:

but the time spent in working the ignition, plus timing map, plus carb tuning, plus custom intakes is really a step backwards not only financially but time wise.

i couldn't imagine going thru all that work, just to have to try and make it run.

but i guess if you're afraid of ECU's and fuel injection i could see the appeal
I’m not sure that is even dual carbs. If you look at the bottom of the intakes there are ports for injectors. Maybe the carbs are being used for a throttle body? Also the engine is missing half the parts still as if it was carbs, I see a missing linkage on the right side and no fuel lines plumed up. So who even knows if this setup ever even was used or ran.

Wed Feb 09, 2022 8:09 am

My Suby swap in my '91 Vanagon has been running for 10 years at this point, the FI has preformed flawlessly from the get go. Why should I want to get back to wheels having wooden spokes and tires made from steel bands?

Wed Feb 09, 2022 9:29 am

Ceckert64 wrote:
I’m not sure that is even dual carbs..

it is. he was mocking stuff up with a hacked up stock subaru manifold with the base flanges welded on

in the end there is a video somewhere of it running. the build was on STF as i recall

this is like putting a carbureted 350 in your M3 because you are afraid of FI. makes zero sense

Wed Feb 09, 2022 11:32 am

Carburetors are nasty in terms of emissions, inefficient with fuel, and are a real PITA in the winter.

How about considering a conversion to electric? It is quite viable, and has a lot of positive aspects. The main negative is the matter of range, which kind of rules it out for campers, especially.

Wed Feb 09, 2022 12:57 pm

EV conversions are extremely viable if you don’t drive more than 200 miles in one sitting/day. That number scares people, but let’s be honest: how many of you drive your buses that far every day anyway?

The cost factor (25k diy, 110k turnkey,) is still leaving those conversions to people with more money than spare time in their lives. Those folks aren’t going on cross-country drives. Let them be the coal mine canaries for the next few years.

Robbie

Wed Feb 09, 2022 1:25 pm

Xevin wrote: :lol: :shock: OEM Subaru carb. I think they stopped using those in the U.S. in 1990. A Justy isnt even a real Subaru. (I had to look. It was a Daihatsu. I was thinking Suzuki.)

The biggest problem with switching to a carb would be the same as the T4 engine, no intake manifold heat. You'd have to fab one.

There were I think Weber progressive carbs for the early Subaru, like 80s models which came with carbs from the factory. I doubt the intake is common.

And what are you going to do about a distributor?

Wed Feb 09, 2022 2:32 pm

airschooled wrote: EV conversions are extremely viable if you don’t drive more than 200 miles in one sitting/day. That number scares people, but let’s be honest: how many of you drive your buses that far every day anyway?

The cost factor (25k diy, 110k turnkey,) is still leaving those conversions to people with more money than spare time in their lives. Those folks aren’t going on cross-country drives. Let them be the coal mine canaries for the next few years.

Robbie

Let me get the $ in drive time out of my bus redo first before I ever think of that :roll: :lol:

Wed Feb 09, 2022 5:54 pm

Interesting. I have no issue with F.I. at all. I started as a mechanic at the dawn of that era and for me Carbs are not something I really like working with.
That said It just seems to me that the hassle of rewiring a CAN harness to work with a Subaru engine is going to be a pain.
I'm on a tight budget but am blessed to live in an era with plenty of late 90's early 00's Subaru's to pick from. It' would be a project and a half so I just want to be sure its what I want to tackle.
Power and economy? Ya, I'm good with that, but as a life long mechanic, I yearn for simplicity as well.
The name "The Rusty Rabbit" relates to my life long love of 77-80 VW Rabbits with the best fuel injection ever made. The Basic non electric CIS system. Such a wonderful system and a thing that was done without the needs of huge piles of vac lines or dozens of electric do-dads. Pure perfection!
I'll keep everyone posted on the direction I go, but I feel like I'm leaning towards a Subaru swap if the type 4 that this old girl came with turns out to be too far gone.

Wed Feb 09, 2022 6:49 pm

TheRustyRabbit wrote: Interesting. I have no issue with F.I. at all. I started as a mechanic at the dawn of that era and for me Carbs are not something I really like working with.
That said It just seems to me that the hassle of rewiring a CAN harness to work with a Subaru engine is going to be a pain.
I'm on a tight budget but am blessed to live in an era with plenty of late 90's early 00's Subaru's to pick from. It' would be a project and a half so I just want to be sure its what I want to tackle.
Power and economy? Ya, I'm good with that, but as a life long mechanic, I yearn for simplicity as well.
The name "The Rusty Rabbit" relates to my life long love of 77-80 VW Rabbits with the best fuel injection ever made. The Basic non electric CIS system. Such a wonderful system and a thing that was done without the needs of huge piles of vac lines or dozens of electric do-dads. Pure perfection!
I'll keep everyone posted on the direction I go, but I feel like I'm leaning towards a Subaru swap if the type 4 that this old girl came with turns out to be too far gone.

I had a similar decision back in late 2020 when I found out that my new to me 76 Westy had a 1.7L in it instead of a 2L and it needed a full rebuild so I went the Subaru route.

It took some time as I did the swap myself including the harness and the cost excluding the transaxle upgrade was about CAN$7,500 (US$6,000). I was looking at a minimum of US$3,500 to build an air cooled 2L but like others have said, was concerned about the quality of VW parts, so it was a fairly easy decision. My donor was a 2.5L SOHC from a low mileage Subaru Legacy so the mechanical and electrical was very straight forward.

Really happy with the results as I just get in a drive now but still have fun fixing/upgrading everything else.