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Guest Message by DevFuse

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H6 vs ej25 & ej22

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9 replies to this topic

#1 Mugs


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Posted 21 September 2008 - 05:13 PM

Ok so here is my theory on the subject, but I want to here from you guys on it. I am getting ready to buy a H20 boxer westy and the first thing that is going to happen is an engine conversion. So here is my theory/questions.

An H6 is going to give me more horse power and therfore require less "energy" to move the westy, therefore it should get me better gas mileage then an EJ25 SOHC an also will power me up the steep grades with ease because the motor will not have to work as hard.
Is this an accurate theory or am I off base and it does not really matter.

This brings me to my next question, I have an EJ22 in the garage that needs the heads re-worked and the crank key area re-worked as well (previous owner screwed it all up trying to do an at home t-belt job...It was cheaper for me to buy a used motor and do an R&R) So basically all I need to do is have my machinist do the work and find a wireing harness, and a away I go. But I would really like to save this motor for an old school suby that will become my "new" backpacking rig...(since I have to sell the 96 leg wagon to finance the westy project)

So What, if any; is the advantage of the EJ25 SOHC over the EJ22. Both are readily available to me and not that much in the way of cash difference. Am I am just gaining a few extra ponies and will it really make that much of a difference in the long run of things, or should I really focus on getting an H6 style motor and going with that?

I want to here from all of you out there that has allready gone through the hoops of this. Thanks in advance.

#2 ShawnW


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Posted 21 September 2008 - 09:26 PM

The vanagons weakest point whether it is waterboxer or Subaru powered is its cooling system.

The radiator is great but the cap should have been put on it.

Its hard to bleed the air out of, like a Legacy but 5x as hard.

The 3.0 H6 motor, in a Legacy in its stock vehicle, runs hotter than a normal 2.5 or 2.2 car. Its got a special radiator, two upper radiator hoses, etc. If you are going to put a 6 cyl in get the SVX. It runs cooler and has a complete kit available from Smallcar.com (fairly local to you out there).

If you havent done a vanagon conversion before I would go with the 2.2 or the 2.5. The 2.2 has easier wiring to deal with if you use a 90-94 harness.

I dont think the gas mileage should even be a factor. All of these are going to be similar. The vehicle itself is more of a factor than the engine is.

#3 Mugs


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Posted 21 September 2008 - 11:57 PM

Ya I know about bleeding the vanagons, we get alot of them in the shop. It would be my first, but I always like to dive right in...That being said going for the svx motor from the get go wolud be something I might try. I would not want to do it again...I.E. put in a 2.5 and then be disapointed/wishing that I had the svx from the start. I am not trying to make a racer but the extra power will come in handy with a loaded westy 2 dogs, 2 kids, and a wife :-\

#4 ShawnW


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Posted 22 September 2008 - 08:51 PM

Take pictures! Cant wait to see it!

#5 Snowman


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Posted 29 September 2008 - 10:53 PM

I helped a friend put an EJ22 in his Westy, and that thing hauled butt with that engine. However, fully loaded, it may not be what you're looking for.

As I see it, the main disadvantage of the EJ25 SOHC is that it's an interferance engine, so if the timing belt breaks, the engine is toast. If you put all new timing gear on it before the install and keep up on the maintenance of it, you should be golden, but it's something to be aware of. If you're willing to live with that risk, the increased torque of the EJ25 might be a big help in a heavy rig like that.

Judging from pictures, fitting the EG33 out of the SVX in there is a bit of a shoe-horn job and may be pretty involved. The EJ22 we put in fit well, without a lot of extra room anywhere, so I'd imagine the longer EG33 may require some body clearancing.

#6 idosubaru


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Posted 30 September 2008 - 09:56 AM

the interference info is also an EJ22 issue depending on year (1997+).

someone put an XT6 engine in one as well. i'm not recommending that route, but it's a 6 cylinder. the SVX is wider, longer and taller but does fit in an XT6 engine bay (saw one two days ago!), so it's not waay bigger.

i'd go for the SVX motor if it fits. highest hp of them all and excellent motors.

#7 r_kirky


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Posted 03 October 2008 - 04:52 PM

I have been considering the same project but with a wolfsburg. I would love to see a thread on the build and lots of pictures.:banana: :popcorn:

#8 bheinen74



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Posted 03 October 2008 - 04:56 PM

i would in no way put in a 2.5, they have headgasket prob's and changing or fixing a hg in that tight area not going to be fun.

#9 NorthWet


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Posted 04 October 2008 - 08:58 PM

Mileage will be better with a 4-cylinder over a 6-cyl, assuming that both engines will be geared similarly, and you don't have to run the 4-cyl at higher RPMS all of the time. (Ring/cylinder friction loss is a mileage killer. Consider how much throttle you need to change idle to redline with no-load.) If the 2.2 or 2.5 produces adequate power this shouldn't be an issue.

The SVX EG33 is a WONDERFUL engine, but it is big and it is heavy relative to the EJs. Also, EJs are far more plentiful if yo need a replacement.

#10 monstaru


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Posted 21 November 2008 - 11:10 AM

i would love to get in on this if you do it mugs.as i live right down the street from the shop.mainly want to see what is involved.

you should stop by sometime.send me a pm with your contact info .and we can hang out .cheers, brian

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