Scotty's EJ22T tech questions
 

OK, I figure I better put my tech questions in the right place, and since I may have several over time, I will put them here and update the first post as they come and get solved. Yes, I am trying to not clutter the board with my basics...

The background and relavent details are in normal text, whereas the essence of the question is in bold. This is done primarily for future researchers. If you answer, please look at the details as well, thanks.

Questions:

1) The Legacy Central forums say that there should be no issues with running lean if I bolt an intercooled TD04 in place of the stock VF11. The sizes are pretty similar, and I will not be turning the boost up. I also figure that the limitation (at whatever boost threshold) will be fuel availablity. The other forum says that for my motor and ECU this means around 12psi, while stock is 8psi. At that point a fuel pump, and possibly injectors are needed, as long as the fuel cut has been disabled/modified. I am under the assumption that the stock ECU will be able to read any increase in air intake from the newer turbo design and adjust the fuel and BPV accordingly - does this sound reasonable?


Answered:
The STi exhaust that I have acquired has the o2 sensor much farther back than the stock location. This means that the wires need to be extended. An internet search tells me all kinds of things, but there is a school of thought that says tampering with the wires is bad. Has anyone ever extended the wires/harness for an o2 sensor? Long term results? Cory says splicing works fine, sweet!

"3-bond", this is some sort of gasket/sealant for an access plate on the rear of the engine block. Can I use regular Aviation FormAGasket or silicone or something? Sperry say Permatex "The Right Stuff" is the answer.

Does removing heat shields from the manifold, up-pipe, and turbo area sound like a really bad idea? Did Subaru over-engineer to make us sound tinny? Consensus is that most heat shielding is a good thing.

Thanks for the time, I am a complete ignoramus when it comes to forced induction and the side effects (including the wallet draining). No doubt more to come, and I will update with results.

Heat shields are usually spec'd for a reason. Radiation from uncovered exhaust components could put a lot of extra heat into places you don't want it to be, raising intake temps, degrading bushings/grommets/hoses, blistering paint on the hood, etc. I don't know specifically what will happen on your Subaru, but I wouldn't do it on one of my cars unless I had to.

Yep! I've cut and chopped them many times! As long as good, waterproof connections are made, (solder, heatshrink) I've never had any problems with any of the splices/extensions I've done.

Or do what I did and use butt connectors and electrical tape. 3 years strong and no problems yet. I actually had to redo it once when fixing an exhaust leak and the tape melts into tight insulation...white trash shrink rap?








http://tbn0.google.com/images?q=tbn:...1169758918.jpg

Get with the times Cody. There are butt connectors that are also heat shrink. You can get them at walmart and I LOVE them.

Heat-shrink butt-connectors? At least you end up slightly guilt-free.

New question about sealing the access plate at the rear of the block.....

When I did the extension for my rear O2 sensor a while back, I used some plain old butt connectors, but then slapped a big old piece of glue-filled heat shrink wrap over the whole thing. When it heats up, it not only shrinks, it seals up all the connectors to be weather proof.

Also, I made sure to stagger my splices so I didn't end up with one big thick stack of connectors.

So perhaps the LSD swap won't work, these ring bolt patterns are definitely not the same.

Measured with calipers, even.

Here are the diffs:

http://scottystrachan.com/hosted/diffs.jpg

Yep! What you have there is what's commonly referred to as a "Subaru R160" and a "Nissan R160"

The parts are not compatible. Notice how the side plates are different? (where the axles go in) What you need is another diff that matches the one you took out of your car, with an LSD (if there's one available) and THEN you can swap the carrier.

*&$@#*%^&@!!!!!!

Actually, the one from my car IS the LSD, so I will have to find a similar open in 4.11.

In other news, the driveline bolt pattern is not the same either. Yes, my blood pressure is OK.

AH OK, then yeah, find the physically matching diff with the correct ratio, and get to swappin!

Luckily, it shouldn't be too hard. The 'Nissan style' with the bolt in side plates that came out of your car is the more popular one, and are available in a BUNCH of cars. Just gotta get the ratio you want and you're good!

Does "I have a 4.11 from an automatic" qualify as "shouldn't be too hard"? :p

Scott, if you want to stop by I'll swap you my newer 4.11 from a 2000 OBS 4EAT for the diff you got from me before. The halfshafts I gave you won't work though, you'll need at least one from elsewhere.

Who do you think you're talking to? And it doesn't matter what trans the car came with, as long as it's the right diff type, and the gear ratio Scotty needs.

so there.

I meant shouldn't be too hard to find. :p And since he got his current 4.11 from me, and it's the 5 speed style, and I also have a 4.11 with automatic style (you told me which was which, but I ated it) I assume one is the correct one for Scotty's Legacy.

Yeah, now if I can just get Cory to swap input flanges (assuming that will need to be done), we'll be all set.

It's not auto/manual that makes a difference. It's the actual build of the diff. They're different, in almost every way, save for the mount locations. If it's the "nissan style" diff that Scotty took out of his car, the input flange shouldn't need swapping.

I got the impression that one was for automatics and one for 5 speeds, but that may have been an assumption from limited data.

FYI: it looks like the leggy rear end is the "newer" style... at least it's the same as all the diffs I was looking at for the SVX.

So Scotty, you should be able to find any 4.11 from a newer Legacy, Outback, or Impreza. I know D&D Dismantler had a 4.11 from a ~'96 Legacy... 'cause I put it on my SVX for a week then returned it when we realized it was the wrong ratio and had smoked my transfer clutch. :mad:

If you can find the one at D&D that I returned, it's already got the case ground smooth for the LSD to fit! :cool:

Haha, I did call them and they quoted me like $250 for a diff. Crack.

Kevin's second one is a duplicate of the first, so that won't work.

I stopped at pickNpull at Carson just now, and they have a couple 4.11's in the correct cases there for $80. But, I'm out of time today, they are closing. :mad:

That's my plan, though.

:lol: $250? They sold me mine for $100. 'Course I was also buying a 4EAT from them at the same time.

You get better deals when you walk in and wave money in their faces, but act like you think they're ripping you off.

Well, I spent 30min locating one in their yard this morning, only to be told $200! I offered $150 in a moment of weakness and fortunately he did not take it. My time for a clean one is worth $75/hr!

Bad news is Kev, that even when I reassemble a working 3.90, the input flange won't fit your driveline.

Rats.

Oh, in regards to the 3-bond question... Permatex Right Stuff is the equivalent, and it's easy to get at pretty much any Kragen/Napa type place.

Sweet, that sounds better than the stuff I already have.

Also, I posted a question in the OP about a small part of the stock STi exhaust system.

I believe that flange/spring section goes between the downpipe and the mid pipe, no? I've never had an STi exhaust, but the WRX exhaust uses those springs around the bolts flange thingy there to allow the pipes to flex/pivot in their soft rubber hangers without leaking.

2 hours door to door for an $80 correct diff - priceless.

Here is that part, I believe that it goes between the downpipe and the midpipe, but I'm not exactly sure.....

STi Stock Part?

That doesn't look very stock. Is that by chance an adapter for a 3" downpipe to a stock mid pipe or something?

That looks just like the doughnut flange on a stock exhaust. The end closest to the "fivestar" logo would be pointing toward the front of the car, if it were a stock piece. What diameter is the tube?

in regards to the cutting and splicing of the o2 sensor.. you probably will be fine, unless you are extending it more than a foot, added wire=more electrical resistance, meaning different readings. some people have issues with this, others dont. the readings will not be so much that your car will run differently, but im not too sure about the long term.

That may be, the ID is freakin huge. I'm not gonna sweat it, and I'll just put the exhaust in duplicating the fasteners of the stock setup.

Vice-versa. Stock downpipe to 3" catback.

It looks like I will be pulling the motor and possibly doing a rebuild. Sperry has the following comments in light of efforts of his own: