BulletProof-TMIC Mod - LGT, 08+ WRX

[f1anatic]

I've used JB weld with great success on the OEM unit.

[fahr_side]

When are you driving that you are stopped more than you are moving? As soon as you start moving, ambient air blows across a more efficient heat exchanger.

Mmm. Not sure about this. All the aftermarket TMICs I have seen have much bigger paths for the charge to flow through, which means that the ratio of surface area to the area of the flow path is lower, which means more air can pass through the core without passing heat to the surfaces inside, lowering efficiency.

Note also that in stop/start use, the IC works more like a heat sink than a heat-exchanger. You run boost you put heat into the IC at a rate that is probably higher than it can reject that heat, so the temperature of the IC rises. When you are back in vacuum two things happen. One is that the IC continues to reject heat to the air passing over the core as before. The other is that it rejects heat to the now cooler charge air passing through it.

It cools down quickly enough, and will stay cooler for longer when stopped.

A larger and more massive IC should rise in temperature at the same rate as a smaller one, given it's surface area to mass ratio is similar, and that it's made of material with the same thermal conductivity. The stocker, with it's plastic tanks, probably doesn't rise in temperature as fast as the all-alloy aftermarket items... plastic heats up more slowly than aluminum and the core probably has a higher surface area for it's mass.

 

I wonder why Subaru stopped fitting the turbo 'chimney' they had on the classic Legacy Turbo... would really alleviate the heat soak issues.

[SeeeeeYa]

BAC, you simply don't get it. And, you seem to have some serious agenda I'm not party to... nor wish to be. If I say light you see color, where in truth only all colors are represented. There are no degrees of right nor wrong relative to correcting the too-often tendency of the stock Subaru plastic-endtanked TMIC to fail. Sure, maybe the majority of people buy aftermarket ICs because they are interested in more power... but maybe not. Listening to my own and others' goals and reasoning over these years many also preface their list of plans with the desire to get not only more power, but power without worry of failure FROM the increased power. Whether on this board or the other Subaru oriented websites, new and experienced owners alike express concern about raising boost, knowing all too well that increase can leave them stranded. This mod removed perhaps the biggest obstacle to the upgrade process.

 

As for all that powa that a big AM TMIC will provide... the truth is, the 05-09 Legacy can use all the help it can get. But 09+ WRXs don't, they come with an improved engine, a bigger turbo, bigger injectors, bigger fuel pump, and can relatively easily produce the magical numbers us old Leggy owners used to dream about and work so hard to get. I didin't develop this mod for a Legacy GT, I developed it for a 2011 WRX that had its turbo-side endtank half way blown/levered/whatever off after going Stg2... mine. I shared it here because it is applicable here.

 

Anyone who imagines JB Weld is preferable, or works as well or even better, needs some help with their reasoning equipment. Seriously. There is no comparison. On my 05 LGT the only saving factor was an engine cover that covered the grossness of my IC fixes, JB Weld, clamps, wires, and other failed crap. There is no one on this forum that has made more footprints down this road than I have. My JB Welded and cabled and clamped LGT's TMIC regularly saw 20psi and meth nozzles. The Perrin that replaced it was a solution for some things, and a pain in the ass in other ways... getting it to fit, finally, was one. Getting the engine cover to look and work effectively was another. And it was definitely, unarguably, heavier. Furthermore, in the final analysis, despite all the tuning, meth, injectors, pump, etc. that Perrin ultimately revealed it had a finite ability and became a bottleneck.

 

This isn't my first trip down this road. There is no argument to be had here. The BulletProof-TMIC Mod completely removes the stock plastic-endtanked TMIC as a source of failure. Any argument about it not being as good as an AM replacement TMIC is moot... who the f cares, it isn't in its job description. Since, for example, my turbo can easily run more boost than my injectors and pump can fuel, a "better" TMIC isn't an issue until I not only CAN, but WANT to spend a couple thousand dollars and a lot of time and effort to get, what?... 20 more whp? Give me a break. The wheel horse power of this platform just the way it sits this morning breaks the tires loose, is a loud socially unacceptable little monster that will get my ass in trouble... and has, btw. Three hundred whp in a car hundreds of pounds lighter than my LGT is enough... for me and a LOT of other people. Clear??

 

Let me repeat... when I traded my 3.0R Limited I knew what I was after because I have, in fact, been there and done that. My AP was ordered while I was on my first get-away with it, my Cobb DP was ordered the week after I returned, my shifter and bushings were installed even sooner. My AEM CAI went on with Stg1. All before 800 miles on the odo. Logging the car after I went to Stg2 less than 200 miles later both thrilled me with the numbers, than crushed my spirit when I saw my endtank coming apart. The car sat, unmoved, for two weeks, while I contemplated a solution. It was just before Christmas and my wife told me to order the Process West IC. I did a lot of soul searching, and in the end honored my original intentions... I was NOt going to feed the need for a fixed IC with sophistic logic that could only lead to further upgrades and The Slippery Slope once again. I passed on the PW.

 

Somewhere in that two weeks watching my new WRX sit unmoviing, hood open, all the frustration of years dealing with this IC, all the years of thought, and a determination to end it once and for all, produced my mod. It is, in essence, as was pointed out by someone else, merely a V-band for the TMIC. It is an elegant, attractive, perfect solution to a long standing problem.

 

Hear me: the BulletProof-TMIC Mod was created for ME and MY goals. I shared it because I am certain many share the same goals.

[SeeeeeYa]

Mmm. Not sure about this. All the aftermarket TMICs I have seen have much bigger paths for the charge to flow through, which means that the ratio of surface area to the area of the flow path is lower, which means more air can pass through the core without passing heat to the surfaces inside, lowering efficiency.

Note also that in stop/start use, the IC works more like a heat sink than a heat-exchanger. You run boost you put heat into the IC at a rate that is probably higher than it can reject that heat, so the temperature of the IC rises. When you are back in vacuum two things happen. One is that the IC continues to reject heat to the air passing over the core as before. The other is that it rejects heat to the now cooler charge air passing through it.

 

A larger and more massive IC should rise in temperature at the same rate as a smaller one, given it's surface area to mass ratio is similar, and that it's made of material with the same thermal conductivity. The stocker, with it's plastic tanks, probably doesn't rise in temperature as fast as the all-alloy aftermarket items... plastic heats up more slowly than aluminum and the core probably has a higher surface area for it's mass.

 

I wonder why Subaru stopped fitting the turbo 'chimney' they had on the classic Legacy Turbo... would really alleviate the heat soak issues.

 

While it isn't immediately obvious, Subaru has engineered numerous solutions relative to airflow in the new WRX. First, the giant hoodscoop has far more than enough input for the TMIC, with vents on either side that allows pressurized air to flow over the turbo and engine while moving, and is a convection "chimney" when stopped. There is far more area for this than on the 05-09 LGTs. Further, vents and ducting virtually surrounds the engine, shunting heated air out of the bay and away from the IC. The better sealing air duct ensures the TMIC is fully supported, yet a similarly sized airflow is left to force air onto and out of the engine bay, or chimneys it upward when stopped. The lack of an engine cover, with the sealing taken care of by a proper duct, in and of itself helps with engine bay cooling.

 

FWIW, just as I did on the LGT, I'm exploring means to improve the CAI's efficiency and weather integrity. This has led me into trying to second guess Subaru's aerodynamics, which, the more I look, reveals a depth of attention to detail I'm finding a challenge to improve. Some success at reduction of IATs as well as removing entrance points for moisture are encouraging.

[SeeeeeYa]

question have you pressure tested after driving to ensure that it didn't start leaking again?. thinking about this with mine after jb weld failed asap on my last i/c

 

Take another look at the picture and accompanying text, especially in my NASIOC thread... a pressure significant enough to break the TMIC with this mod installed would be immensely destructive, beyond mere worry about an IC. The TMIC to TB hose would go at the least, long before the IC. But, no stock turbo, for certain, nor any aftermarket turbo either for that matter, can produce a pressure that will threaten the modified IC.

 

I actually bought five JB Weld packages, reluctantly committed to completely covering the tabs on my compromised IC. Knowing that it would work was countered by knowledge it would fail, too, as you and others have found. But beyond that, dealing with the messy ugliness was the main impetus for my mental search for an alternative. I just couldn't stand the thought.

[Th3Franz]

A bigger hood scoop would be awesome. Can't fault you there.

Enjoy the car. You've done a lot of convincing for yourself to avoid the mod itch

[BAC5.2]

You said "I also argue that it is better than most of the aftermarket alternative". But your arguments for that are wrong or irrelevant. I have no agenda, because I don't really care all that much. I like your solution, but I disagree that a fixed stock TMIC is better than an aftermarket TMIC.

 

Your solution eliminates blowing endtanks. That's all. From a performance and efficiency standpoint, the stock intercooler doesn't stack up to aftermarket units. Your solution makes the stock intercooler more reliable. But an aftermarket intercooler is better in terms of performance, and better in terms of longevity. The turbo will run cooler, the charge density will increase, and you'll make the same power at lower boost. All of those things make for a more reliable setup overall. You said yourself it's not all about power, but it is about reliability.

 

If all you want to do is keep the stock intercooler together, and aren't interested in making the most of your setup, then this is a perfect solution. Of that I do not argue. But don't be fooled into thinking there is nothing to gain from an all aluminum, bar-and-plate intercooler. That's all.

 

Fahr, that would be correct if the flow channels were hollow. They aren't. They are internally finned. So while wider, they have greater internal fin surface area, and that's just as important as exposed surface area. The real, measurable difference between bar and plate, and tube and fin, is all about flow area. More flow area, less pressure loss, more efficient turbine and if the exchanger is adequately designed more efficient heat transfer. You could run a big aftermarket turbo with an aftermarket TMIC, but you couldn't do the same with a stock TMIC.

 

This could all easily be put to bed by taking internal core temperatures on a car tuned for both types of intercooler. One at the inlet and one at the outlet of the intercooler. That's a sure fire way to find the efficiency of a core. Personally, I don't care all that much. I've got an aftermarket intercooler sitting on my bench ready to install when my exhaust is done. I got it merely as a point of reliability, and I got a deal on it that made it worthwhile.

[fahr_side]

While it isn't immediately obvious, Subaru has engineered numerous solutions relative to airflow in the new WRX...

You're preaching to the choir mate. Look at my profile... it's obvious to me every time I lift the hood.

[fahr_side]

Fahr, that would be correct if the flow channels were hollow. They aren't. They are internally finned. So while wider, they have greater internal fin surface area, and that's just as important as exposed surface area. The real, measurable difference between bar and plate, and tube and fin, is all about flow area. More flow area, less pressure loss, more efficient turbine and if the exchanger is adequately designed more efficient heat transfer.

Oh, I agree with you. I had read that many of the ICs on the market are not finned / turbolated. Can you see into yours well enough to know it is?

 

BTW, I am also considering a TMIC upgrade for more flow / less pressure drop... I'm willing and able to see the pros and cons of both stock and aftermarket parts.

[BAC5.2]

I can. I'll try to snap a picture the next time I have it out of the box.

[SeeeeeYa]

A bigger hood scoop would be awesome. Can't fault you there.

Enjoy the car. You've done a lot of convincing for yourself to avoid the mod itch

 

Avoiding the mod itch.... hmmmm. Not entirely, right? Stg2+ before 1kmi? Remember also, this 11 WRX at this level flows 300 g/sec. Translate that to chp. and multiply by this MT's ratios. As they say, this "isn't your father's GT."

 

It isn't so much convincing myself, as it is the finite that I embrace better now. The limitations of the clutch and transmission are an example. Going further would break things I don't want to break, things I thought were indestructible in the early days with the LGT I now know are not. I learn the hard way.

 

Besides, I'm already at a place with the WRX, power-wise, that I worked years and spent many thousands reaching (then dealing with) with my LGT. I have the power, the handling, the daily fun of a lighter car, with the familiarity of a powerplant I know and prefer. I tried to justify an STI... but it wasn't as nice a DD, and its raison d'etre and my goals were incompatible.

 

Where I'm now happily at, is where some wiser members have remained since the beginning. While they have been quietly enjoying trouble free Stg2ish power for years I spent searching, and spending, and repairing.

[SeeeeeYa]

You said "I also argue that it is better than most of the aftermarket alternative". But your arguments for that are wrong or irrelevant. I have no agenda, because I don't really care all that much. I like your solution, but I disagree that a fixed stock TMIC is better than an aftermarket TMIC.

 

Your solution eliminates blowing endtanks. That's all. From a performance and efficiency standpoint, the stock intercooler doesn't stack up to aftermarket units. Your solution makes the stock intercooler more reliable. But an aftermarket intercooler is better in terms of performance, and better in terms of longevity. The turbo will run cooler, the charge density will increase, and you'll make the same power at lower boost. All of those things make for a more reliable setup overall. You said yourself it's not all about power, but it is about reliability.

 

If all you want to do is keep the stock intercooler together, and aren't interested in making the most of your setup, then this is a perfect solution. Of that I do not argue. But don't be fooled into thinking there is nothing to gain from an all aluminum, bar-and-plate intercooler. That's all.

 

Fahr, that would be correct if the flow channels were hollow. They aren't. They are internally finned. So while wider, they have greater internal fin surface area, and that's just as important as exposed surface area. The real, measurable difference between bar and plate, and tube and fin, is all about flow area. More flow area, less pressure loss, more efficient turbine and if the exchanger is adequately designed more efficient heat transfer. You could run a big aftermarket turbo with an aftermarket TMIC, but you couldn't do the same with a stock TMIC.

 

This could all easily be put to bed by taking internal core temperatures on a car tuned for both types of intercooler. One at the inlet and one at the outlet of the intercooler. That's a sure fire way to find the efficiency of a core. Personally, I don't care all that much. I've got an aftermarket intercooler sitting on my bench ready to install when my exhaust is done. I got it merely as a point of reliability, and I got a deal on it that made it worthwhile.

 

BAC, you're a hoot . First, I've addressed the "getting the most from" my setup. I think the problem here is familiarity with the 09+ platform... I HAVE the most already.

 

Then, you end with the sentence which defines MY position: "I got it merely as a point of reliability..." Thank you. Sincerely. I'm going to cross post this over "there" just so your reluctant truth can serve to untangle others' circuitous logic.

 

Legacygt.com FTW.

[BAC5.2]

I'm glad you'll forcibly misinterpret what I was saying.

 

Not reliability from an endtank failure standpoint. Reliability from a system standpoint.

[Th3Franz]

Avoiding the mod itch.... hmmmm. Not entirely, right? Stg2+ before 1kmi? Remember also, this 11 WRX at this level flows 300 g/sec. Translate that to chp. and multiply by this MT's ratios. As they say, this "isn't your father's GT."

 

It isn't so much convincing myself, as it is the finite that I embrace better now. The limitations of the clutch and transmission are an example. Going further would break things I don't want to break, things I thought were indestructible in the early days with the LGT I now know are not. I learn the hard way.

 

Stage 2 before 1000 miles.. you didn't waste any time hehe.

 

Are the gear ratios that much different? Are they shorter?

 

What problems did you have with your LGT?

[hadvw]

Wow, looks almost exactly like the "prototype" I worked up about a year ago! I think we found the same C-channels at Lowes! I think you even did the 1 C-channel inside another one like I did! Have you been sneaking around my garage??

 

http://legacygt.com/forums/showthread.php/bolt-up-turbocharger-upgrade-119177.html?p=2921454

 

The only problem is: there is no clearance on the driver's side of the LGT layout to put the bolt that would go closest to the front. I kinda got distracted with lots of other stuff (and then rain!)..

 

But, if the passenger's side (the one I have working) is the one that mostly fails, then I'll just put that part of my prototype onto my actual TMIC, and let it be..

[SeeeeeYa]

Stage 2 before 1000 miles.. you didn't waste any time hehe.

 

Are the gear ratios that much different? Are they shorter?

 

What problems did you have with your LGT?

 

As far as I knew, the reasons the newer WRXs have a better transmission than earlier versions is because they have the Legacy's five speed MT. So... you should be familiar with the tranny.

 

My LGT was an auto, with eventually a complete IPT trans and TC. Before that I broke a rear axel and the destroyed the rear diff. Most of the real damages to the drive train happened autoxing . The 5EAT succumbed to the AVO380 and meth.

 

The reason the new WRXs don't come with a LSD, I'm led to believe, is to minimize breakage of the drivetrain parts. They rely instead on traction control routines. It is surprising to me to squeal tires in my Suby going around a corner, and breaking the tires loose on compromised asphalt under sharp accel. That never happened with the LGT... it broke instead.

 

In a similar vein, although regretting the "loss" of the ventilated rear disc, I find absolutely nothing to criticized about the WRX brakes.

 

Although the new WRX is in almost all ways a legacy, it's also pleasantly different and weighs hundreds less. I like the hatch, and I like it being shorter. It's wider. combined with detailed changes to bushings and suspension geometry, the WRX handles the curviest roads, under power, with ease. Despite having a street-friendly compliant ride, it remains composed on any road, rotating with a confidence inspiring ease where my altered LGT would threaten me with its mechanical neutrality. The 11 WRX is everything I loved about my Legacy GT, but lighter, more nimble, slightly more in-context raw, and devoid of the slightly middle-aged facade of the LGT. It's a great car if you don't mind casting "stealth" and "sleeper" to the wind.

 

The five speed is my kind of manual... four speed with overdrive. It has been many years, sadly, I realize now, since I gave up this kind of relationship between machine and me, in favor of the more urban convenience of an auto trans. Too long.

[SeeeeeYa]

Wow, looks almost exactly like the "prototype" I worked up about a year ago! I think we found the same C-channels at Lowes! I think you even did the 1 C-channel inside another one like I did! Have you been sneaking around my garage??

 

http://legacygt.com/forums/showthread.php/bolt-up-turbocharger-upgrade-119177.html?p=2921454

 

The only problem is: there is no clearance on the driver's side of the LGT layout to put the bolt that would go closest to the front. I kinda got distracted with lots of other stuff (and then rain!)..

 

But, if the passenger's side (the one I have working) is the one that mostly fails, then I'll just put that part of my prototype onto my actual TMIC, and let it be..

 

Amazingly similar, differing basically in detail. Seventh used my post to fab up one similar.

 

However, after numerous attempts, the dimensions of the elements I use are skin tight and fit everywhere. During choices, I had to compromise on some hardware due to size, and resort to making my own 'bolts' to fit right. And you're right... that driver's front corner is the closest. However, using U-ch cut as I do with the hardware I used, that corner fits fine. It's in the pictures. Remember, this WRX is just like an LGT, under the hood especially.

 

Putting your existing pieces on your working stock intercooler will definitely make it as strong as you need, even just using that turbo-side bracket. If you would care to refine them slightly, to fit better, I can provide the detail.

 

I will point this out... as you notice the rails you used are bowed in the middle, the result of tightening the ends well. Not a real issue, but I note it because pieces cut my spec snap firmly onto the IC and bed fully against all three interior surfaces... which while also will bow if overtightened, do not rely on being tightened whatsoever beyond merely snugged gently. The 'bolts' only serve to keep the rails on the seams, the rails holding the seams together.

 

Nevertheless, mister... good for you.

Edited April 1, 2011 by SeeeeeYa

[fahr_side]

The reason the new WRXs don't come with a LSD, I'm led to believe, is to minimize breakage of the drivetrain parts.

I doubt that. My EDM WRX has VLSD in back and 4.444:1 final drive.

[SeeeeeYa]

I doubt that. My EDM WRX has VLSD in back and 4.444:1 final drive.

 

Not quite sure of the object of your doubt... obviously I'm talking about USDM and not EDM, and we certainly do not get the LSD. As for the "why" I guess that will always be speculation since FHI doesn't usually confide motives.

 

Some searching just now verified exactly what I've determined independently just by my short experience... the new ones handle better, stock, than the older ones typically modified. Also, from those apparently in the know which I am not, the LSDless WRXs handle better on a track as a result. Seems some believe if you have AWD an LSD is not required and can be a drawback. I don't know, not going to track it myself.

 

Given my history of driveline damage, as well as the copious anecdotal evidence, I'm happy with the car's setup as it is. A little tire squeak and spin is infinitely preferable to breaking things.

 

Tell more about the EDM vs USDM differences in the new WRXs... I'm already aware we get leftovers relative to other markets, may as well pour salt into the wounds. For example, do the EDM WRXs get the plastic TMIC also?? Or a good one like the STI?

[fahr_side]

Not quite sure of the object of your doubt... obviously I'm talking about USDM and not EDM, and we certainly do not get the LSD.

 

Tell more about the EDM vs USDM differences..

I doubt the reason you have no LSD is anything to do with breakages, since our diff, axles etc are otherwise identical, and with the 4.444 final drive we are putting a lot more torque to the wheels.

I don't think a VLSD in back makes the car behave much differently in most situations to be honest.

 

EDM WRX has the same engine, turbo, intercooler etc. but the DBW mapping is much smoother out of the box.

We got power mirrors, HIDs and headlamp washers as standard, plus the splitter and sideskirts which I think were options for you. Fog and reverse lights are also different.

On the flip side we got no A-pillar airbags.

 

You might want to ask this question on a forum like clubwrx or 3gwrx... probably get more answers.

[rao]

They left of LSD due to cost, plain and simple.

[SBT]

^ Agreed - cutting corners to keep costs down, pure and simple.

[mwiener2]

On the flip side we got no A-pillar airbags.

 

that's cause your government hates you

[camber]

No rear vlsd was quite common in the US for LGTs before the bl/bp. It was the weirdest thing because Canada got a vlsd but the US spec LGTs did not. However, Canadians pay a lot more for their LGTs.

 

Cost cutting..

[fahr_side]

that's cause your government hates you

So we're even then.