legacycentral bbs

Been following the board for quite a while but haven't registered till today.

Just picked up a motor out of a 91 turbo legacy yesterday for $250. I have a 93 legacy L 5MT.

I'm going to work the car over with the turbo engine, different suspension and brakes. Since I have the ej22t in my posession, that is what I am focusing on now. Also, since I'm a student, my funding is a much slower process. When it warms up (Duluth is cold) I'll go get the ecu(maybe), crossmember, sensors on the shock tower, rear endlinks(mine has no rear sway bar) and possibly the rear vented brakes.

My goal with this motor at this time is to make 300-350hp, since I have read that is what the bottom end is roughly good for. I'll get around to checking the compression on the ej22t one of these days. I'd rather not dig into the motor if I don't have to. Maybe down the road I'll swap to some newer heads, but that is out of the scope of what I want to do with it right now.

I realise I'll need all of the proper supporting mods to make it work. I'm going with a fmic, most likely a Spearco unit measuring 29x6x3. They say it is good to 345hp or so, and it'll get sprayed flat black. As far as turbo goes, I've been looking at a few of the VF's. Any reccomendations? VF22, VF39 from STI? Any input here would be appreciated. What do you guys do about the fact the the compressor inlet is right behind the intake riser? I've been considering rebuilding the up-pipe to angle the turbo so the intake can have a straighter shot, and so room won't be such an issue. I'm a mechanical engineering senior and and have access to our shop with bender, 3-axis CNC mill and CNC lathe, so doing that is not a big deal.

I'll get the Walbro 255 l/h fuel pump, and far as injectors go I've read on this board about the sr20 injectors working. I've seen some pretty good deals on ebay, like $300 or so for 500-600cc.

I'd like to see if Cobb would sell their stainless cast bellmouth and cat without the piping, as I'll go with a custom 3" all the way back.

I'll need a clutch, any reccomendations would be healpful. I've heard bad things about CLutchmasters.

I guess my biggest questions are about tuning. I'd like to get away with an S-AFC, but someone here stated that the ecu will pull timing at some point so I'm scared of going that route. Is there anyway to do it safely without a standalone like the Link Plus? Its just that they are damned expensive. I do like the idea of being able to run MAP instead of MAF with a standalone though. I don't like the idea a butt tuning it, but atleast there is a four-wheel dyno down in the cities.

I saw the thread about doing the basic conversion, and I probably should re-read it.

I think I covered everything, sorry about the long post. Any suggestions/ideas would be helpful and greatly appreciated.

I think it is a bad way to start by NOT tearing the engine down. All that time and money you are going to pour into it, and if it is a junkyard motor, it would suck to have it be sub-par, or just fail on you 500 miles or so down the road.

With the motor out, its only about 5 hours to yank the heads, send them out to be rebuilt, and pull the pistons and clean them, scour the cyclinders, and install new rings. And replace the front and rear seals while you are at it. And the water pump. There. New engine in 5 hours.

Easier said than done for many people Douglas.
I wish I could do all that, I know I can, but...

Anyways, I would look into a Mitsubishi TD05-16g turbo for your car. There are ones made specifically to fit Subarus. They can be found occasionally on e-bay or you can get brand new warrantied units from deadboltspeed.com for a killer price. That turbo is good for what you want and more.

Duely noted. Its not that i'm not capable of rebuilding the engine, I was just trying to avoid rebuilding it when I wasn't planning on beefing up the bottom end, although it would make things easier when I really want to go nuts-o with it down the line.

Do you think the main and rod bearings should be fine? Or should I be ok not splitting the crankcase?

About the TD05-16G. How big of a pain is routing the piping for a fmic? I was thinking about rotating the turbo to make that a bit easier and also getting rid of the 90 degree bends in the piping. Is it a waste of time?

Quick question. I understand that it is not possible to get 300hp without doing a head swap. Is this truth or myth?

The rods and bearings "should" be fine. Very, very seldom do they go bad unless the motor was run hard hard hard.

I have been pushing my stock NA block hard and it has 230-240,000miles on it and the only bad noises it makes are out of the passenger side head (I hope thats where it is coming from!)

I suggested doing the heads, rings, and pistons because it is easy, you just have to have the confidence to due it. Since you had some other ambitious plans that required some wrenching, I assumed you could figure out what to do, especially with the motor out.

If you don't want to do the bottom end, you should at least do all the top end seals, gaskets, pumps, etc.

Steve

irishsetter wrote:Quick question. I understand that it is not possible to get 300hp without doing a head swap. Is this truth or myth?

Myth....

I've thought about scrapping the car itself altogether since the front end is a bit smacked up from me smiking bambi's mom at about 100 ticks(long story). Getting a newer chassis doesn't really gain me anything mechanically, and would more of a pain in the ass with the newer emissions junk and wiring. Besides, I don't mind the look of the 1g legacies and I really dig how much of a sleeper it could be. IT would also make a really nice winter car when I get out of school in a couple years and can hopefully afford an sti. Don't have a little too much fun and change majors like me or you'll be on the seven year plan


Oh, and any suggestions on injector size? I hope those nissan injectors can be put to work as there plemty of options.

heh i feel the same way as u about not doing the bottom end on the engine for now. i was thinkin about gettin the heads done tho.

quick question. since everyone says the heads on the legacy turbo dont flow well, if i got them ported and polished would that be better than upgrading to any other heads out there? if it isnt, then wat heads would be a better upgrade? thanks


Don

I don't know about rebuilding it now. I can pull my engine in short time with a little help from one of my brothers or a buddy. So I wouldn't worry one way or the other.

I would replace all the seals, don't forget the rear cam seal near the turbo like me.

TD05-16G or a VF12 from overseas would bolt on and are good for power. TD05 being the bigger turbo.

I have a S-AFC that I plan to play with when I get home and you will hear how it goes on the board. Pulling timing is good for safety, bad for power if it's too much.

The heads I'd leave alone for now. If I was going to get new ones I'd get EJ20G or SOHC 2.5 but there are a lot of options.

irishsetter wrote:Quick question. I understand that it is not possible to get 300hp without doing a head swap. Is this truth or myth?

myth.

What s-afc model do you have K

So with better heads, stock turbo, IC, MBC and more fuel is 300hp possible. This is assuming that exhaust is not a issue.

I don't know about the stock turbo, but anything is possible i guess, you'd need some engine management if it was possible. I'm sure someone will give you a better answer.

Running the fmic piping is a pain but moving the battery to the trunk and getting an intake makes it easier by creating more room to work with. I also had to move my horn.

The whole thing about the heads being sub-par has never been backed up with solid repeatable proof.

They flow a little less on a flow bench, but no one has put different heads on a 2.2t and then said how much more horsepower they freed up blah blah blah. But there have been plenty of people that have built up the EJ22t into a monster with the stock heads.

Yes, if you start pushing 400+ hp, then different heads will get you farther, just because you can rev higher and other little things. But basically people just go with DOHC is better and think that the SOHC heads need to go... even though they are fine. With turbos you can push more air through anything with boost.

Definately let me know how it goes with the s-afc. If I could could save $1200 on electronics, I'd be happy.

I'm curious. Is it possible to flip the intake around? I can see that its way different than the NA intake, maybe I could that one. It might be a pipe dream, but that would make my IC plumbing a lot shorter and less of a pain. My ac was gone a while back and making custom brackets to move my alternator to the right would not be a big deal in our shop at school. I suppose my throttle linkage would be a pain to figure out. I dunno if the ends would justify the means but it shure would be cool.

I doubt 300hp is possible with the stock turbo. If you could even get that kind of boost pressure out of it, it would be so far out of its efficiency range that it would blow really hot air and get extremely hot itself and not last very long. Compressor maps are our friends

As far as turning your intake around, it is technically doable but you will have to move your alternator and mess with your throttle linkage as you know. There might also be some hood clearance issues. There has been a little discussion about this and somewhere floating around is a pic where a guy just put a plate on the backside of the intake and put a flange on the front. Same results with probably a lot less work. It's something that I plan on doing someday when I have a turbo and a FMIC. When it comes to tearing the engine down, I'd definately follow the advice of others and replace seals and such while you can easily and before trying to build it much. Also - welcome to the board.

Does anyone have any hard facts about the head swap?

If you plan on making big power it probably wouldn't be a bad idea to rebuild your bottom end while its out of the car. Id test your compression and go from there.

Anyways i would recomend unichip in a piggyback system mine works good and you can control boost electronically as well as adjusting fuel and timing.

sounds like the 16g would be good if you just want to bolt on a new turbo. but since you said you could easily do a rotated mount you might want to do that. That will allow you to easily fit different turbos on latter, namely ones that are designed for the much more tuner friendly wrx.

Injector wise you could bump up around a hundred flow rate (or whatever that number) is by getting some older jdm side feeds from a 2liter

just some ideas
sam

Do you know where an extra 100 cc's/min would get me boost wise with a nice fmic? I was thinking i'd want to be in the 15-17 psi range to get the output I'm looking for but I'm not shure. I'll check out the unichip if I can do all you said.

Some sr20 injectors would be nice if they can be made to work without too much hassle. They seem to readily availible.

I'd like a turbo that gave me a nice spool-up and was pretty efficient in the flow range I'm looking for but I know one can spend serious $$$$ on the good stuff.

I have a S-AFC II
Not installed yet but I'll put it in when I get home and have some fun working with it.
I don't see 300hp on the stock turbo. On the stock heads yes.

simonasaur- I checked out unichip's website. Looks like a good product. Do you have to get it from a dealer and have them tune it? I'm up here in Minnesota where it appears that there isn't a dealer for them. I'd rather not flatbed my car to another state just to tune the thing. There are a few tuners around here and I think they'ed be plenty capable of handling it.

It sounds good though. I handles fuel, timing, and can control boost, which is all I'm really looking for.

Brat4by4 wrote:Yes, if you start pushing 400+ hp, then different heads will get you farther, just because you can rev higher and other little things. But basically people just go with DOHC is better and think that the SOHC heads need to go... even though they are fine. With turbos you can push more air through anything with boost.

But the easier the air can flow through the better, right William?

The stock heads COULD probably be built up to be impressive and flow pretty well, but then again, the USDM Legacy Turbo is the only Forced Induction EJ, with SOHC, so Subaru must have thought something about the benefits of DOHC. I can't think of a current Turbo engine that is still SOHC...

Think of it like a straw. You COULD blow the same amount of air out of a stirring straw as you could a drinking straw, but with the stirring straw, there's significantly higher pressure at the compressor outlet. That forces you to run a larger, and laggier turbo to compensate for the astronomical boost levels you would have to acheive to obtain the same results. You could barely puff on the drinking straw, and flow just the same. So you could run a less aggressive turbo, maintain quick spool, and still have potent power through the rev range.

An engine is just an air pump, and the heads are what the air must flow through. It's just gotta work that much harder, the less the heads flow.

I'm not saying DOHC is the be-all and end-all if you want to make big power, but I am saying that there are pros and cons to each.

SOHC usually has more down-low torque. DOHC usually has more up-top huff. It's all a trade off. I don't mind downshifting to accelerate. I don't ever try to grandma drive and be in 4th gear at 30mph. I can accomidate any downfalls of DOHC, for the benefits that they provide my specific driving needs. Your needs may be different, everyone's are, so you may actually be better off building a big SOHC.

When Matt and I were both about even with WRX's in speed, we would pull on them, then we'd clear 5000 RPM, and they would start to reel us back in. Even at wastegate boost with the 16g (which holds boost to the stock redline). Pull on the WRX, then they start to get back at you beyond about 5000 RPM.

Plus, high redlines are conductive to good power delivery (space below the curve).

BAC5.2 wrote: SOHC usually has more down-low torque. DOHC usually has more up-top huff. It's all a trade off.

This is a common misconception. If you have the same number of valves that are of the same diameter being operated by cams of the same spec, the engines will perform nearly identically. Sure, since the valve angle is different and each will have slightly different parastitic losses they won't be quite the same, but close enough.

There are 2 (3 if you count marketability) reasons that manufacturers use dohc vs. sohc; higher revability for the $ and the ability to use variable valve timing.

For revability it's mostly a matter of expense, sure eithe dohc or sohc could probably rev however high the manufacturer wants, but dohc will do it for less money and better emissions. It also reduces the moving mass. Yea, you add another cam, but since it is operating fewer valves and doesnt have to control the motion of the rocker arms, it can be thinner. This also means weaker valve springs can be used, and that these weaker springs will not be subject to the same stresses.
A sohc engine can overcome these limitations with heavier duty (or double/triple) valve springs. Those springs aren't cheap, from a manufacturers standpoint, and they wear on the engine a bit harder. I've heard instances of snapping cams, but they were always in somewhat abusive circumstances. In a subaru, each cam is only operating 8 valves, and is very short, so the need for dohc isn't as profound. Our 6500rpm redline is because the valves float a bit beyond that on our old springs, and since the power is all gone at that point, it's not a hindrance.

As for vvt, im not gonna do much detail here, but basically you need a different cam operating your intake vs exhaust valves to take advantage of vvt. If you wanna check out something interesting, see how they did it on the VW vr6.

Oh, on some engines there's not enough space on the cam to run 4 valves/cyl. This, coupled with the fact that a manufacturer will opt for dohc for a cheaper rev-happy engine is what makes it seem that a sohc engine can't rev, or is only good for tq.

I'm not lecturing you, bac, i just figured id give more info than less. Josh ought to comment, i know he took some engine design classes at one point.

Thanks for the info Scott.