Subaru EG33 + My car!

[AkumaNoZeta]

I've been thinking of about an EJ swap for the past week or so. This is what I've been thinking so far. This is without knowledge of where or how the engine mounts are or anything. Also assuming tubed front end with SLA/double wishbone front suspension fabricated. I'm not a very good Microsoft Painter but it should give you an idea of what I'm thinking. So far the measurement in red is the one I've been looking for but can't find at all anywhere.

[Daeron]

I've been thinking of about an EJ swap for the past week or so. This is what I've been thinking so far. This is without knowledge of where or how the engine mounts are or anything. Also assuming tubed front end with SLA/double wishbone front suspension fabricated. I'm not a very good Microsoft Painter but it should give you an idea of what I'm thinking. So far the measurement in red is the one I've been looking for but can't find at all anywhere.

 

Were you planning on trying to keep the Subaru gearbox on the EJ? If so, your diagram is entirely off. The front driveshafts of the Soobie gearbox stick out right about the middle of the two cylinder bores. If you are trying to set it fully behind the front axle, then you are commiting to either a RWD layout, or a fully divorced transfer casing and front differential like a pickup truck.

[AkumaNoZeta]

I was planning on keeping it RWD. I don't know about the gearbox issue though. I have an extra T5 so I was thinking of getting an adapter bellhousing machined for the EJ but that would be lots of bucks plus the T5 from 5.0 Mustangs aren't exactly that durable (why do you think I have an extra one?) I figure the best option would to get one with a transmission and just eliminate the front differential portion of it.

[Daeron]

I figure the best option would to get one with a transmission and just eliminate the front differential portion of it.

 

Not as easy as it sounds; The only good option (bear in mind I am far more familiar with the generation of engines and transmissions immediately preceding the EJ, but the auto gearbox on the EJs is identical to one that was prototyped in the older models, so I cannot be too far from the mark) is to simply remove the front drive axles and "plug" them up.. but you are still spinning the entire front differential assembly. "Just removing it" isn't an option, it is an integrated transaxle.

 

 

The 3 speed automatic that was in MY old subaru (EA series, NOT EJ) was the same FS23985098120983C gearbox (don't know the number exactly) from Hitachi that was also put into the automatic Z-cars and RWD Maximas, the pickup trucks, and the 240SXs. The Electronically controlled 4 speed auto that was fitted to later Subaru EA series cars, was its direct descendant (andhonestly, much more related to the 240SX auto and the later pickup autos than our old 240Z auto.) All of the gearboxes, manual or auto, are made by Hitachi, for both Subaru and for Nissan.

 

ALSO, at one time, I had done some research and discovered that the input shafts on the transmissions (i think i was checking an S30 trans) were QUOTED as having the same diameter, and the same spline count. Note: this is research done via parts website lookup, NOT hand-eyeball measurement. In other words, the Subaru clutch disc might well spline onto the input shaft of, say, a 5 speed from a 240SX.... AND there is even a fighting chance that you could remove the bellhousing from an EJ transmission, and splice it onto a 240SX transmission. (Similar to what has been discovered with using a 240SX 5 speed on an L28.)

 

 

 

There is data out there that suggests ALL of this could be relatively simple. (Also, I am fairly certain I posted it earlier on in this thread.) Nobody has yet taken the opportunity to physically check out the transmissions and the engines and see what would need to be done to make it work.

[AkumaNoZeta]

So you're saying that you can't just remove the ring and pinion gears that go to the front axle?

 

I think my best option would be to find a suitable transmission that will fit like you said because the transaxle looks really long in the photos which makes sense because in the Impreza the engine does sit in front of the front axle line and has to extend all the way to the cockpit for the shifter.

[Mul-ti-pass]

I'd love to see this swap happen. Here's your red measurement. Actually this is measured at the inside of the exhaust ports. It wouldn't be much wider with an aftermarket header, but the stock cast iron ones are very thick. Let me know If you need any more numbers.

[AkumaNoZeta]

Thanks for the photo, that came to 20.7 so I'm confident I can do it now. So after I get back home I'm gonna start putting all my spare parts on eBay to try to get a good chunk of cash to buy an engine now. I've gotten so many free parts over the past year or so, a Z full literally. Since my Z is sitting I have it FULL of spare parts, and I even had to store other parts underneath the car. It would be a start at least, something to put aside until I find a job or join the service, depending on what happens.

[AkumaNoZeta]

Actually, some other measurements that would be nice is bellhousing bolt pattern and input shaft length so I can hopefully find a RWD transmission to fit it.

[Mul-ti-pass]

Measurements are not perfect, but should be accurate to at least two tenth's of a millimeter. I didn't know which numbers you might need so I put them all in. I hope it's not too many. I no longer have a clutch to measure, but the input shaft bearing on the flywheel is about 8.9mm in from the bellhousing mating surface.

 

 

[AkumaNoZeta]

Whoah, you're awesome. Did you take all the measurements yourself or did you find them somewhere? I meant the other end of the bellhousing, the part that bolts to the transmission (if the transmission and bellhousing aren't one unit) but I feel like I'm asking too much from you now.

[Mul-ti-pass]

Yeah I did those myself with my digital calipers. Sorry I don't have any transmissions to measure. On the WRX the bell housing is not bolted on. It's Basically one piece. However the STI at least looks more promising.

 

WRX

 

STI

[AkumaNoZeta]

Those are awesome looking, something I'd like to have in my house as a conversation peice. Thanks for taking all the time to get me the info, I think you just might be more excited about the idea than I am I guess it's time to find a suitable trans, if all else fails I can just get a custom bellhousing.

[AkumaNoZeta]

Do you have the measurement from the front to back of the engine? I've read it was 18" but I don't know if that was the 4 cylinder or the 6 cylinder. Also, is the physical size of the engine different between the EJ20, 22, and 25s? I assume they're all the same block and heads and stuff, just different bore/stroke, but I don't really know.

[Comrade_Charlie]

most subys trans have the fwd axles like that in the trans.

[Mul-ti-pass]

A few more.

 

[WizardBlack]

Notice that the front axles are in the supposed "bell housing". The section that that piece bolts on to is the steel girdle for the trans with fittings to route a trans cooler to it. You will have to find a way to either eliminate the front differential or shift the motor very far forward. Likewise, you can see the plastic and rubber dogbone sticking off of the front of the trans. It swivels on it's mount point on the trans.

The photo in post #66 shows the bottom view of the engine with the plastic timing covers added (and pointed down). Post #71 with the STi trans shows how much further back from that that the axles for the front wheels are.

All Subaru engines have very similar dimensions, but the exhaust manifold is different. A factory turbo exhaust manifold will shoot straight down from both exhaust ports, but will also take room to the right of the passenger exhaust flange and also room behind the passenger head for the turbo; which usually sits behind the passenger head.

 

Hope that helps.

[AkumaNoZeta]

Those transmissions posted above are stick-shift manuals right (not some stupid paddle shift ones that are popular today)? If so how far back is the shifter mounted on them? Would the shifter to engine block measurement be similar? If it is I could just look for one of those, I just don't want the shifter coming up at my elbow because of the engine set-back.

[m4xwellmurd3r]

Those transmissions posted above are stick-shift manuals right (not some stupid paddle shift ones that are popular today)? If so how far back is the shifter mounted on them? Would the shifter to engine block measurement be similar? If it is I could just look for one of those, I just don't want the shifter coming up at my elbow because of the engine set-back.

Look at the STI transmission. You can see where the shifter hooks on to just to the left and a bit forward of the output shaft.

[AkumaNoZeta]

So it mounts on the outside like the old skool and racing 4speeds do? Do they run by mechanical gears or hydraulic/electric servos like automatics do? Basically if I remove the front differential can I get rid of most or all of that wiring that's on it? It looks like there's a lot of stuff there, I like the simple transmissions where the only wire going to it is the reverse lights wire and of course the speedometer cable. I guess I should just see if I can find an Impreza repair manual huh? Off to Amazon.com I go.

 

Well I just got back from Amazon. I couldn't find an Impreza repair manual but there's a Legacy one so next time I'm able to stop by an AutoZone or something I'll see if they have the book. I was thinking the EJ25 would be better since it's higher displacement. But I doubt the Legacy had a transmission on par with the WRX or STI version so the manual would be pointless for that huh? Good thing I have so much free time to think about what to do.

 

Sorry about all my questions, the gearbox is the only thing I have yet to have figured out enough yet. If it would be easier for you all I'm just gonna spend my time finding as many articles as I can and read those first. I'll get back to you all later. Thank you for all the help though.

 

Found this on a different forum:

"i'm told that gen3 rx-7 transmissions will install w/ minimal drilling, and will mate properly to the svx engine, and since the svx engine will mount to the other subaru transmissions it's reasonable to assume because a=b b=c then a=c, that you could shoehorn in a manual rx7 transmission and have rwd"

 

But I don't know if it's reliable, no one on the forum seemed to even notice that statement at all.

[WizardBlack]

You see on the STi pic, the shroud around the opening for the propshaft? It is plated in zinc? Just above it and behind a bit is the linkage for the shifter. It's a squared-off "U" shape and also plated with a gold zinc. That's it.

STi's use just the one linkage and it's mechanical. The forward versus rearward shifter gates are achieved by pushing/pulling that link. To move from the left, to center, to right, to reverse lateral gates, the link is twisted. Kinda like a joystick hooked to the other side of a simple cantilever system. Look up aftermarket short shifter kits. Some of the complete shifters are retrofit and should show the majority of the shifter linkage. The shift knob, when sitting in neutral, should be maybe four to six inches past the end of the tranny, I'd say. Roughly.

I think all four cylinder engine blocks for the last 10~15+ years bolt the same to mounts and trannies. The STi engine block is different on cams and whatnot, of course. The last couple years they have changed quite a few things rapidly, but I think the basic bolt-on stuff is still the same as always. That's one of the nice things about Subaru.

I know that there are swapout center diffs (IIRC) that ppl use to make a Subaru RWD to dyno them. Not sure if it works on the STi 6 speed, however. The 6 speed is a very well engineered and very tough trans.

Don't buy an RX7 tranny.