Former member - getting a craving - built OBXT questions?

[JoeFromPA]

All,

 

My wife had an 08 LGT 5MT from brand new in March 2008 till January 2012 and put 94k miles on her in that time. We loved that car - stock turbo, stock clutch, stock TOB.....only had one very minor electrical issue and looked damn near as good as the day we bought it from we TRADED it in for 14k. Bought it new for 25k, so that was ridiculous value retention considering it was a trade-in.

 

Anyway, I've got an F80 m3 now and she's got a 2008 BMW 535xit wagon which she loves.

 

 

After a few feet of snow, I'm getting a craving and wanted to seek advice here.

 

My questions

 

Sorry to post this in an LGT forum but I'm a former member and know this forum gets more action:

 

What engine setup would you recommend for dead reliable daily driver OBXT capable of 120mph trap with maximum spool/engine responsiveness on pump gas (not corn)? Are we talking twin scroll setup or could I achieve a really nice, responsive daily driver with a Vf52 or BNR18 or other turbo (think more responsive than the stock restricted engine)?

 

I'm going to build out on paper a ~2008-2009 OBXT running a 6mt with an upgraded suspension and some nice fat tires and see what I'd be running cost wise. Part of going that route for me is only if I can achieve some serious accelerative potential while being bulletproof and responsive to minor throttle inputs (i.e. both a fast spooling engine & appropriate gearing).

 

If it's worth it, I'll give some serious thought to a build. If not, not

 

Edit: Removed the quarter mile time, just using trap speed as an indicator of power. If I can trap around 120mph, I'll have more than enough power. If that's really a high-spend build to achieve, I'd be willing to aim for 116mph

[Rhitter]

VF52 won't do it. I don't drag, but it looks like you need over 350whp to hit 120. To get to 350whp completely reliably takes money. To be "dead" reliable and with the spool / responsiveness you are talking about, this could easily be $20k.

 

Bilstein BTS kit for the suspension (if you want to stay high)

http://legacygt.com/forums/showthread.php/bilstein-bts-outback-xt-kit-pictures-111880.html?t=111880

 

Borgwarner EFR twin-scroll kit (full race makes has some cool set-ups) for the responsiveness you are talking about.

 

 

Take a look at this thread (this car probably doesn't have the spool / engine responsiveness you want)

http://legacygt.com/forums/showthread.php/oldskoolbikers-08-outback-xt-cosworth-efr-7153-build-241476.html?t=241476

 

Read this starting, at post 523

http://legacygt.com/forums/showthread.php/new-bw-efr-turbos-coming-soon-through-fr-147277.html?p=5226510#post5226510

[BarManBean]

See my build thread for possible ideas, pretty similar to what you want although my power level might be a touch low as I have aspirations of sticking with the stock shortblock.

 

I have pieced my build together over several years (spanning back to parts I had from my previous car). If I were to do it all at once and just buy everything all at once I would expect to write a check for $10-15k no problem for parts and labor.

 

I'm in the process of refreshing my motor (maintenance stuff) and switching to a custom 16g turbo and expect to be somewhere solidly in the 300-350awhp range (really, could be anywhere in that range). Not sure what that translates to in terms of trap speed.

[Mike07LGT]

You're gonna need at least 350whp to trap 120... my sti had over 400 and I was running 11.6@123mph. That was with an FP Red on race gas

[BarManBean]

You're gonna need at least 350whp to trap 120... my sti had over 400 and I was running 11.6@123mph. That was with an FP Red on race gas

 

Not trying to sound like a dick here, but I imagine that final trap speed has a LOT to do with the driver mod also.

[Robe30]

I'm jumping in on this thread because I'm in a similar situation. My 05 OBXT gave up the ghost last week and it's at my friend's Subaru shop waiting for me to assemble a build list.

[JoeFromPA]

Thank you all. It's interesting - I actually put alot of value on daily driveability and "squirt" - moreso than trap speed, which can simply denote a top-end beast that launches in an abusive fashion and stays in boost.

 

I'm considering decreasing my thoughts a bit here....I was using 120mph trap speed as a proxy for the level of mid-range I like (as seen by the fact I DD a ~400rwhp/400rwtq car that hits full torque below 2000rpms).

 

However, the reality is that the subie block doesn't flow well at the top-end and so getting those trap speeds is an exercise against nature - but what I really want is fat responsiveness from 2500-5000 rpms which can be had with ~350awtq + appropriately short gearing.

 

Sorry for the stream of consciousness - this is helping refine my thinking. Thank you. If a custom made 16g or similar can yield 350 wtq on pump gas at around 3000 rpms, that might be on the table.

 

....

 

P.s. Looks like rallitek offers stock-height upgraded springs for the OBXT with 18% higher spring rates. Might be a good choice for my desire to maintain ground clearance.

[Rhitter]

2500 RPM is pretty low for a single scroll subie turbo. A custom VF40/VF46 might give you what you are looking for (Edit, for early torque not for the total number).

 

A 16g is not going to give you 350 wtq at 3000 rpms, but probably can at 3300-3500. Not sure if that's too late for you.

 

If you want 2500, you will need to look at a twin-scroll set-up.

[JoeFromPA]

I'd seriously consider a twin scroll setup - would be changing up the IC and exhaust setup anyway most likely (IIRC, the stock IC wasn't solid at those power levels and would split at the seams anyway).

 

I'm going off memory here, but I believe the stock block - with proper fueling and tuning of course - would be very solid at the 350wtq level indefinitely and I'm not looking to bring boost up to 7000 rpms so the rotating assembly should be fine too. The twin scroll setups of years ago I priced out at around $6k all-in....I think that was a JDM legacy twin scroll setup....are there better twin scroll setups now for low-end response?

 

Thanks for the help and guidance.

[Rhitter]

 

I'm going off memory here, but I believe the stock block - with proper fueling and tuning of course - would be very solid at the 350wtq level indefinitely

 

This is very much a YMMV statement. Some are, some aren't. I think those that are running at 350wtq are mostly ready for the block to go at any time.

 

Mine went at a stage 2 setup (under 300 wtq). There are quite a few who seem to break ringlands around stage 1-2.

 

There are also a lot of others who are completely fine for many many years on the stock block (Max Capacity is one)

 

The issue is, whatever car you get, could have a preexisting problem that running it at 350 wtq reveals.

 

If you build brand new with an OEM shortblock and proper tuning and fueling, you have a much much higher chance of it working (Max Capacity / Sgt.Gator)

 

The problem is you never know.

[BarManBean]

Is Underdog still selling his twinscroll setup?

[JoeFromPA]

This is very much a YMMV statement. Some are, some aren't. I think those that are running at 350wtq are mostly ready for the block to go at any time.

 

Mine went at a stage 2 setup (under 300 wtq). There are quite a few who seem to break ringlands around stage 1-2.

 

There are also a lot of others who are completely fine for many many years on the stock block (Max Capacity is one)

 

The issue is, whatever car you get, could have a preexisting problem that running it at 350 wtq reveals.

 

If you build brand new with an OEM shortblock and proper tuning and fueling, you have a much much higher chance of it working (Max Capacity / Sgt.Gator)

 

The problem is you never know.

 

Hmmm, ok.....wondering if this project creep might destroy my value proposition. Now I'm talking built block for my desired power levels.

 

Starting to wonder if there is a better platform to start off of - I just have such good memories of our LGT And darn if it isn't hard to find something with in a MT, 3500 pounds, AWD, wagon, and this tunable.

[BarManBean]

Wanna buy my car? I'll build the motor however you like it given that it's already out of the car?

 

[JoeFromPA]

You had a 6mt already and a 16g in it...I don't think I'd buy it while the engine is out, as I'd want to keep you motivated to get it back in correctly....but that has potential

[Mike07LGT]

Not trying to sound like a dick here, but I imagine that final trap speed has a LOT to do with the driver mod also.

 

Possibly, but show me a legacy/outback with under 350whp trapping 120+....

[JoeFromPA]

Back on this band wagon and looking around again on what's on the market in a XT outback. Resetting my goals to ~300-325awhp with really immediate throttle response/power onset even down to ~2500-3000 rpms.

 

Looking to somewhat replicate what was done here, except with more focus on handling and power output and my only real off-road focus being soft beach sand with significant ruts from large truck tires.

http://indefinitelywild.gizmodo.com/how-i-turned-my-subaru-outback-into-a-real-adventuremob-1716068985

[Max Capacity]

I guess you haven't read my click here link. hint, hint, hint.

 

With proper fueling the VF52 should get you where you want to be.

 

I have Koni Sport Yellow's and Epic springs from "m sprank" the car handles really well.

 

Not you need to lower your car if you want to clear ruts.

[JoeFromPA]

I guess you haven't read my click here link. hint, hint, hint.

 

With proper fueling the VF52 should get you where you want to be.

 

I have Koni Sport Yellow's and Epic springs from "m sprank" the car handles really well.

 

Not you need to lower your car if you want to clear ruts.

 

I did read your link actually....all 22 pages. Not a single comment on throttle response/power onset as far as I could tell

 

I also read "it's all in the tune" about 27 times, while a respected shop kept chanting "go forged pistons". Seems to me even with a tune, a number of folks have had #4 ringland failure. Might be a reasonable insurance to go with a forged piston during a re-build, no?

 

I really, really want a 6mt in a wagon. No offense to the 5mt, but given the strength and smoothness of the 6mt, and gearing, it seems like a desirable transmission.

 

But the cost to transplant one isn't worth it...

 

Decisions, decisions...

[BarManBean]

Your best bought is probably to keep an eye out for an OBXT with a blown motor and just build it. might just take a bit to find the right deal.

 

With my motor out at 88k (still, lol) I'm not going forged and I'm not even replacing my head gaskets (which are fine). Forged motors often, but not always, have some downsides. I'll hopefully run mine with a solid tune and be fine. If something pops I'll rebuild it most likely with forged bits.

[legacybt]

Take a peek at this build: Blurred GTX2867R. It's done on a single AVCS stock block, and should hit your requirements quite nicely. I'm saving up to do a very similar build with my car.

 

In my opinion, the turbo setup is about perfect for our engines (depending on application of course - in this case street & autocross, with occasional track days). The 300wtq limit allows the use of a stock 6mt clutch and keeps the engine in safe limits, and having 375 whp at 7000 rpm would be fantastic.

 

Yes you could tune to have more area under the curve and have an overall faster car with this setup, but it would start to push the stock block and clutch limits - and lose the novelty of a turbo that pulls hard from <3000 RPM to redline.

[Gex]

Why has no one said a Dom1.5xtr build. It is way better than a disco potatoe (2867),18g, etc... It is the perfect EJ turbo. My car is an absolute fricken riot to drive on the street and would trap 120 on the 20psi map all day. Maybe even on the 17psi map (360hp/350tq wheel mustang dyno). My car hits hard at 3300 and pulls all the way to 7. It has impressed many people, many of whom own 350+hp sports sedans and cars. It is IMO the best EJ setup around. Not too much and definitely not too little. Plus if you want 450-500hp at the wheels all it takes is a little bigger injector and corn juice.

[legacybt]

Why has no one said a Dom1.5xtr build. It is way better than a disco potatoe (2867),18g, etc... It is the perfect EJ turbo. My car is an absolute fricken riot to drive on the street and would trap 120 on the 20psi map all day. Maybe even on the 17psi map (360hp/350tq wheel mustang dyno). My car hits hard at 3300 and pulls all the way to 7. It has impressed many people, many of whom own 350+hp sports sedans and cars. It is IMO the best EJ setup around. Not too much and definitely not too little. Plus if you want 450-500hp at the wheels all it takes is a little bigger injector and corn juice.

 

Also a great option! Love your build Just to be clear though, the GTX2867R is a very different animal compared the old disco potato. Take a look at this compressor map extents overlay:

http://www.atpturbo.com/root/releases/images/release110111/GTX2863R-vs-GT2860RS.jpg

[Max Capacity]

I did read your link actually....all 22 pages. Not a single comment on throttle response/power onset as far as I could tell

 

I also read "it's all in the tune" about 27 times, while a respected shop kept chanting "go forged pistons". Seems to me even with a tune, a number of folks have had #4 ringland failure. Might be a reasonable insurance to go with a forged piston during a re-build, no?

 

I really, really want a 6mt in a wagon. No offense to the 5mt, but given the strength and smoothness of the 6mt, and gearing, it seems like a desirable transmission.

 

But the cost to transplant one isn't worth it...

 

Decisions, decisions...

 

 

As far as throttle response, it all depends on which gear your in. If your in the power band throttle response is instant with the vf52. If the rpms are to low, you need to down shift. pretty much the same thing with any car.

 

For normal driving I just roll into the throttle and I can feel the car push me back into the seat.

 

I also find the wagon snappier then the Spec B. I know the wagon has more WHP, but when I stab the throttle the wagon pushes you back in the seat instantly. The Knoi's & Epic's help with that, the Spec B wants to transfer weight, you can feel the front end lift a bit, the wagon just moves forward.

 

The turbo spools at 2400 rpm and pulls well to 6000 +. I do have some head porting done. I will say the car pulls hard in 2nd and 3rd gears when passing cars on back roads.

 

With the blast plates on the 5mt, it shifts much smoother and goes into 3rd cleanly at high rpm shifts.

 

 

 

I know Mike from AZP tried hard to talk me into forged pistons, at my power level and a little more I feel they are not needed. May be I trusted my Tuner to much.

[JoeFromPA]

As far as throttle response, it all depends on which gear your in. If your in the power band throttle response is instant with the vf52. If the rpms are to low, you need to down shift. pretty much the same thing with any car.

 

For normal driving I just roll into the throttle and I can feel the car push me back into the seat.

 

I also find the wagon snappier then the Spec B. I know the wagon has more WHP, but when I stab the throttle the wagon pushes you back in the seat instantly. The Knoi's & Epic's help with that, the Spec B wants to transfer weight, you can feel the front end lift a bit, the wagon just moves forward.

 

The turbo spools at 2400 rpm and pulls well to 6000 +. I do have some head porting done. I will say the car pulls hard in 2nd and 3rd gears when passing cars on back roads.

 

With the blast plates on the 5mt, it shifts much smoother and goes into 3rd cleanly at high rpm shifts.

 

Thanks for all the guidance Max. I remember in my LGT the soft suspension and how just moving to Koni's increased the accelerative feel very nicely.

 

Sounds like the Vf52 path would pretty much get near my aims. Just curious: What are your thoughts vf52 vs BNR 16g evo? or even similar small turbo but using a ball bearing CHRA