Interesting weekend at the dyno...

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Interesting weekend at the dyno...

Postby roninsoldier83 » Mon Apr 13, 2009 9:14

I actually went into MAC Autosport yesterday for only a baseline with my buddy Dave who just bought a 2007 Dodge Charger SRT-8, with no intention of having my car tuned again, just for fun. My car had been previously tuned on E85 back in September, and again in December after I added an AEM CAI, GMS inlet & APS TMIC. When I made my first baseline pull, my heart skipped a beat when I saw how lean the car was running... leaner than 13:1 AFR equivalent under full boost, needless to say, I was shocked that it was that lean. The last tuner to tune my car (Adam at Revolutions Performance), well, it's safe to say I will never be visiting them again, as last I were on their dyno, IIRC my AFR's were supposed to be around 12.0:1/.80 lambda (since it was my second time on that dyno I trusted him and didn't ask for an AFR graph), considerably richer (or so I thought) than my car was running just 4 months later. This was done on my AP V1, the E85 map being a RealTime map.

I can only assume that my former tuner either a)had a faulty wideband, or b)made a few changes to the tune after the last pull/prior to pulling it off his dyno, or c)somehow the tune "slipped". Regardless, I have no idea how long it's been running that lean, but it is a true testament to the detonation resistance of E85 that I'm not buying a new motor right now. I considered that maybe my fuel filter was clogged or something of that nature, but after tuning, my IDC's were right where they should (76% at 19psi on E85 w/811cc injectors, note that ethanol requires ~30% more fuel than gasoline under WOT) be at the boost/AFR levels I am running on E85, leading me to believe my fuel system is in good running order.

Either way, at the recommendation of my new tuner (Nick at MAC Autosport), I decided to ditch my AP V1 (for reasons I'll not mention here) and instead let him tune my car via OpenECU. With the same boost pressure (19psi), and MUCH richer AFR's (low 11's), he made a bit more power across the entire powerband. I was very impressed to say the least. Although, Nick was actually shooting for higher boost pressures (20-21psi), that we weren't able to attain (my previous tuner had the same issue), and since we didn't have a smaller "pill" (to put inside the line running to the wastegate) to help my OEM BCS out, we were pretty much stuck with 19psi peak. Although Nick believes with either a smaller pill, or either a 3-port BCS/Hallman MBC, tuning for 1-2psi more boost, we can make an additional ~15whp or so. I'll likely be picking up a 3-port BCS, retuning, and posting results not too long from now.

This is what we came up with:
Image


^^^Since dyno numbers really don't mean a damn thing when compared to other dynos, for reference, these kind of power levels at Bandimere should equate to trap speeds exceeding 106mph, which with a good 60ft & shifting should be good for high 12's. I know a couple guys with STI's (so same gearing/powerband on stock turbo) on MAC's dyno that made right at 340whp, and at Bandi were trapping 108-109mph for reference (running 12.6-12.9 ET's).

On another note, I can no longer recommend anyone to Adam at Revolutions, for various reasons, besides just my car running a LOT leaner than it should have... thank goodness for det resistant ethanol. For anyone that doesn't know, Subie's on pump gas are usually tuned between 11.0-11.5:1, and on E85, even 12:1 is considered aggressive... leaner than 13:1 under 19psi is WAY more aggressive/dangerous than I would want on my daily driver. Beyond that, asking the guy questions almost never led to direct responses, could never get a response via PM (on Pirates) or email ect.

Along with selling my AP V1, I'm also going to finally break down and buy another laptop (haven't had one in years, since my old one was damaged in Iraq), a tactrix cable, download OpenECU software (it's free!), pick up an LM-1 WB02 so I can datalog AFR's, and learn to tune my car myself, or at least datalog more often. I've tuned with piggybacks in the past, but never anything flash based, so I'm sure it will be an interesting learning experience.

Just felt like sharing. Have a good one!

-Brandon

P.S. there was no cool down period/cheater bag of ice on the TMIC in the final pull. Final numbers were after multiple WOT pulls with no cool down.
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Postby roninsoldier83 » Mon Apr 13, 2009 9:14

Forgot to mention mods:

-OpenECU tuning (free software for Subie's & Mitsu's) on E85
-Cobb catted downpipe (yeah, it's still running a cat... that's a first for me! lol)
-Borla XR-1 (closest stock looking 3" exhaust I could find lol).
-AEM CAI
-GMS inlet hose (Eff installing another one of those)
-APS TMIC
-811cc injectors
-Walbro 255lph fuel pump


Just an FYI for other Subie owners, since I know there's a couple on this board... I installed the AEM CAI, inlet hose & APS TMIC all at the same time, and had the car retuned.... VERY minimal power gains, we're talking 3-4whp with all 3 mods combined. Although it did move peak power a few hundred RPM's over to the right, which was nice, and around 10whp more at redline. For the most part though, on a stock turbo (TD04-13T, VF39/43/52/53 ect) they're really not worth the cash IMO. If you see a tuner than "makes more power with XX intake", it is truly just the tuner manipulating boost/timing/AFR and/or icing down the IC/comparing a hot run to a cooled run.

The main reason those 3 parts are on my STI is for the future... as the VF39 (stock turbo) will one day be replaced. Spend wisely, and know your power goals. Happy modding!
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Postby Rich » Mon Apr 13, 2009 9:14

I love how boxer engines are so torquey. Those are some good numbers for sure. What turbo do you have in mind for an upgrade? Nick was saying he likens the K04 to a TD04-15G, and suggested a GT3071r-wg for an upgrade. I'd think a GT3076R for your STi?

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Postby roninsoldier83 » Mon Apr 13, 2009 9:14

Rich wrote:I love how boxer engines are so torquey. Those are some good numbers for sure. What turbo do you have in mind for an upgrade? Nick was saying he likens the K04 to a TD04-15G, and suggested a GT3071r-wg for an upgrade. I'd think a GT3076R for your STi?


Actually, I wasn't thinking anything that big... or pricey lol. I like Garrett turbos, they probably have the most advanced ball bearing center cartridges of all the main turbo manufacturers (IHI, Mitsubishi, Hitachi-Borgwarner ect), and as such, typically have the fastest spooling/most responsive turbos for their size... but the cost of entry is pretty high comparatively, and there's a few complications:

1. Price. $1895 entry for a GT3071R in stock bolt-on location.
2. ALL GT30's come with a 3" inlet.... my inlet hose is 2.4". They make a reducer (which I don't trust the idea/fitment of), but ultimately I would be choking the turbo.
3. I could install a 3" inlet.... yeah, about that, talk about a PITA install... but beyond that, in order to get a 3" inlet to fit, I would have to remove my TGV (tumble generator valves), which I am not willing to do. TGV's help with cold start, and I run ethanol year round. No thanks.
4. Honestly, anything much larger than a 44 lb/min compressor, my APS TMIC would start to become a hindrance, as repeated pulls on a turbo capable of holding 22+psi at redline would cause me to scale down the boost, or be forced to buy a FMIC, and I want to keep my TMIC for throttle response/simplicity sake.
5. On E85, with my current 811cc injectors, I would run out of fuel overhead up top probably around 20-21psi or so.
6. I could get a rotated mount kit to avoid the 3" inlet & TGV issues, but at that point, we're talking $3000+. More than I'm looking to spend, and again, would force me to run a FMIC.

Whereas, for $1000 or less, I can easily pick up a 20G, that would bolt right up, and work well with all existing parts. It's a 44 lb/min compressor, so nothing too huge/extreme. At Bandi, a guy I know named Miguel, with his '05 STI, was able to run a 12.2@112mph with a slipping clutch. IIRC, his fastest trap was 113mph at Bandi. So, IMO a 20G is more than fast enough for a daily driver. Now I'm just trying to decide on what trim of 20G, go for more power with a TD06H hotside in an 8cm housing, or maintain more response/faster spool at the cost of a little top end with a TD05H in either a 7cm or 8cm housing. I'm still undecided, both have their merits, and I have to always remind myself, this is still my daily driver. We'll see :)


Honestly though, either a 71 or 76 on the 2.3L MZR would be a fine choice IMO. The Suby has slightly more displacement (2.3L vs 2.5L), but IMO, the combination of DI & higher compression in the MZR motor more than make up for it, and I'm willing to bet would produce a VERY similar powerband. With motors like these, it's hard to choose a turbo sometimes.... go with the slightly smaller compressor, and you'll have better response/less lag, however these cars have such short ratio 6-speeds, "lag" can easily be controlled with a flick of your right hand, and sometimes I think would be better suited to a motor that made peak power at a higher RPM to really get the most out of your gears. It's a tough choice, but at least there's choices available :D
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Postby Rich » Mon Apr 13, 2009 9:14

The tough choice is lb/min flow. I don't want to max out the stock fueling system, but I want ~300whp on a load bearing dyno. The 3071r-wg seems to be what I'm looking for (with a custom exhaust mani for T3 inlet/EWG and v-band on the DP side).

I don't know shit about Mitsu or IHI turbos, so it's hard for me to equate TDxx with GTxx.

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Postby roninsoldier83 » Mon Apr 13, 2009 9:14

Rich wrote:The tough choice is lb/min flow. I don't want to max out the stock fueling system, but I want ~300whp on a load bearing dyno. The 3071r-wg seems to be what I'm looking for (with a custom exhaust mani for T3 inlet/EWG and v-band on the DP side).

I don't know shit about Mitsu or IHI turbos, so it's hard for me to equate TDxx with GTxx.


Well, the general rule of thumb is 10hp (crank not wheels) per lb/min, which is "possible", although, typically optimistic. Obviously at sea level as well, too many variables at altitude.

IHI turbos have no logic to them... none. Whatsoever. Seriously, the largest IHI ever really made was the VF22, it's larger than the VF39 (stock 04-06 STI turbo), but the VF43 is the EXACT same size as the VF39 (only a different IWG), both of which are larger than a VF23. The VF36/37 are twin scroll, and about the same size as the 39/43. Numbers have no relation to size. IHI's make no sense. Stock STI turbos VF39/43 typically are rated around 35 lb/min, meaning it *should* be limited to around 350bhp, however there are a couple guys at sea level who have ran as fast as 11.7 on a VF39 (full weight), and trapped as high as 116mph... so obviously, more than 350bhp is possible (especially if you're willing to push the compressor FAR out of it's efficiency range, which will ultimately reduce turbine life & raise IAT's), but then again, IHI pretty much never releases compressor maps, so again, it's debatable on what they're actually rated at, mostly just speculation and opinion.

Mitsu turbos are pretty easy to read. The first number is the hotside:

TD04, TD05 & TD06, mostly refer to the turbine wheel, the bigger the number, the bigger the wheel. When someone refers to 7cm or 8cm they're talking about the housing they're inside. Obviously a larger housing=larger surface area=typically flows more. The turbine will usually have a large impact on your torque curve. A smaller housing will offer better response/less lag, as the wheel will spin "quicker", but will ultimately be choked as RPM's/exhaust CFM's go up.

The second number, 13G/T, 14B, 15G, 16G, 18G, 20G ect refers to the compressor housing. Just like the hotside, the bigger the number, the bigger the compressor. The compressor determines the lb/min of air the turbo can flow. However, only by looking at the hotside can you tell what the boost threshold (amount of lag) is going to be, the compressor will only tell you how much air you can push. To give you an idea:

-18G compressor is rated around 40 lb/min compressor.
-20G compressor is rated around 44 lb/min compressor.

Garrett's work JUST like Mitsu's, GT really just means ball-bearing IIRC (opposed to their old T-series turbos), and really Garrett is one of the only companies that makes a truly ball bearing turbo, most other companies employ inferior journal/roller/thrust bearing designs. This center cartridges is one of the reasons they cost so much. A true ball bearing cartridge will always outperform a journal/thrust/roller bearing design when it comes to reducing spool & overall responsiveness (sometimes spool time & responsiveness are thought to be the same thing, when in fact they're not). You can make a turbo "spool" at a lower RPM according to a dyno graph just by introducing more of a load (i.e. pulling in a higher gear, starting at a lower RPM ect) and make a turbo appear VERY street friendly, but often times a graph will not show you response on the street/track, this is where Garrett turbos REALLY shine. BB>All.

Just like a Mitsu, the 30 in GT30 refers to the hotside, and the bigger the number, the bigger the wheel. GT25, 30, 35, 40, 42 ect. Works the same way as Mitsu.

The second number, the 71, 76 ect, refers to the cold side (compressor). Same as Mitsu. To give you an idea, how they stack up:

-A GT3071R is rated to flow 47 lb/min.
-A GT3076R is rated to flow 52 lb/min.


^^^There's actually a little more involved with Garrett turbos, but that's the general idea.

So, overall, a 20G is a little smaller than a GT3071R, in theory, should put out around 30hp less overall, but I'm not too worried about it, a 44 lb/min compressor is just fine with me :)

If you're only looking to make 300whp on a load bearing dyno (I'm assuming either of the Dyno Dynamics at either Revolutions or Super-rupair), and are planning on using either of their half or 1.15 correction factors, a GT3071R should more than get the job done. I've seen quite a few people with 20G powered Subies put down well over 300whp on both Revolutions' & Super's dynos, some over 330whp. Hell, there was a guy with a LGT recently with an 18G that put down 317whp on Super's DD (although that car is more of a freak exception, not the norm), and a 3071 is bigger than both those compressors, should be more than enough for you :)

Although, with proper fueling & tuning issues addressed, with an equal sized compressor, I would expect a 2.3L MZR motor to make a bit more power than the EJ25, due to the cooling properties of DI & considerably higher compression (9.5:1 vs 8.2:1). Rule of thumb: for every 1:1 point of compression, should yield approximately 4% power gain. I've heard of efficiency rumors of DI yielding as much as 10% additional torque (torque vs RPM=horsepower... so.... yeah), so as long as your fuel system can keep up & you are able to properly tune, I would think a GT3071R *should* put you over the 350whp range on Super's dyno... but, that's just speculation.

Were you planning on running an IWG or EWG?
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Postby roninsoldier83 » Mon Apr 13, 2009 9:14

Just did the math, Harvey claims on Super's dyno, a stock STI puts down around 224whp. Which if we are to assume it's a 300bhp car with an AWD drivetrain loss, we should multiply the BHP by about .75 to come up with the WHP figure on Harvey's dyno (with 1.15 CF in average conditions).

That said, at the crank, assuming the MS6 has a similar drivetrain loss as an STI (both AWD), to hit 300whp on Super's dyno, you should be around 400bhp. So, basically, a 40 lb/min compressor *should* get the job done, assuming you have a large enough hot side to hold torque at a higher RPM (aka, make higher peak HP) and have no significant breathing restrictions that might limit the turbo's potential.

In short, with proper fuel overhead needed to push boost pressures required for those power levels, and a good tuning solution, a 47 lb/min compressor like the GT3071R should be MORE than enough to get you there.

Again, these figures are only approximations based on theoretical turbo efficiency on a Port Injection motor. DI adds more to the equation, but either way, a GT3071 should get you more than the power you desire, assuming you're not limited on boost/timing due to potential knock (low octane fuel, heat soak/high post-IC IAT's, lean AFR's due to lack of fuel) or breathing restrictions choking your turbo. Which, if you can get fuel & tuning taken care of, I think you'll be ok :)
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Postby Rich » Tue Apr 14, 2009 9:14

I'm looking at a GT3071r-wg, possibly running a T25 turbine inlet to keep creep down and sticking with the IWG....might do a port job on it at most. Also looking at a v-band DP and a full 3" intake tract. Would like to run ~16 psi with this setup.

http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=GRT-TBO-025&Category_Code=GRT

or I may go with this GT2871R...

http://www.extremeturbosystems.com/product_info.php?products_id=1413

If I can't keep the creep down, custom mani w/ 38mm Tial EWG.

I'd also throw in water/meth to keep knock down.

Any suggestions?

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Postby roninsoldier83 » Tue Apr 14, 2009 9:14

Rich wrote:I'm looking at a GT3071r-wg, possibly running a T25 turbine inlet to keep creep down and sticking with the IWG....might do a port job on it at most. Also looking at a v-band DP and a full 3" intake tract. Would like to run ~16 psi with this setup.

http://www.atpturbo.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=GRT-TBO-025&Category_Code=GRT

or I may go with this GT2871R...

http://www.extremeturbosystems.com/product_info.php?products_id=1413

If I can't keep the creep down, custom mani w/ 38mm Tial EWG.

I'd also throw in water/meth to keep knock down.

Any suggestions?


Honestly, from everything I've ever read on the internet about boost creep, it made me paranoid with my STI. I was scared to go catless, ect ect, due to all the crap I read from people on Nasioc. It was all for nothing.

I've experienced boost creep.... although to be honest with you, I just about have to induce it myself. Seriously, the only time I ever have "boost creep", is if I decide to floor it at a low RPM in 6th gear. From 3700rpm or so & up, not only does the car/boost not "creep", I can't get the damn thing to hold peak boost lol. Which is completely normal for a turbo of this size.

Basically, the only times I experience creep are all self caused (which I caused a couple times at most). During normal daily driving, or hard driving, creep isn't really an issue. Easy solution to avoiding creep? When you want to speed up, rather than flooring it in 6th either only go partial throttle in 6th, or the more obvious solution: downshift.

As far as the 2871 vs 3071 debate goes... well, I've actually given this a lot of thought. They both have the same 71mm/56 trim compressor wheel, you're just going to run a smaller turbine with the 2871. Basically, they'll both be able to push the same amount of air (boost) at the same efficiency level, but the turbine will determine your curve. The 28 will spool faster, but fall off up top... the 30 will take slightly longer to spool, but will hold more boost up top.

With a car like the Speed6, I actually think I would go with the GT3071R. The 2.3L MZR motor has 9.5:1 compression and 2.3 liters isn't all that small for a 4 cylinder. More importantly, that car takes 2 shifts to get to 60mph, aka, VERY short gearing. What it needs IMO isn't more low end torque, it has short enough gearing (torque multiplication) and decent enough low end response, that a few hundred more RPM's worth of lag won't be too noticeable. If we were driving cars with Corvette style gearing, where 1st gear went well over 50mph, I might say differently, but traditionally, cars with shorter/close ratio gears benefit from powerbands that make peak power at higher RPM's, as that will allow you to using your gearing advantage to a greater degree/not have to short shift constantly like I'm sure you find yourself doing on the stock turbo.

As far as the meth/water goes... I have mixed feelings. Are you running a FMIC or TMIC? If you're running a FMIC, and only plan on running 16psi, as long as your tuner knows what he/she's doing, knock shouldn't be an issue. Honestly, I like the throttle response/simplicity of a TMIC (although even in stock form, my STI's TMIC setup didn't suffer nearly as much as my Speed6 did from heat soak), but the main reason I don't plan on running a FMIC with a 20G is that I'm already running E85. To anyone who isn't familiar, E85 has a latent heat of about 310 btu/lb, whereas gasoline is only about 110 btu/lb. Translation? Ethanol does a GREAT job of cooling an air charge, enabling me to push higher boost pressures (aka higher IAT's) with a much lower chance of det.

At 16psi on a GT3071, knock should not be a problem with the proper fuel & timing tables on that motor on pump gas IMO, assuming your intercooler is able to handle the job of keeping post-IC IAT's down. For a decent read on intercoolers, take a look at this:

http://perrinperformance.com/pages/show/92

^^^Pay no attention to the dyno graphs, as dyno numbers can be skewed, but pay CLOSE attention to inlet/outlet air temps with the 3 intercoolers listed. Surprisingly, the Perrin TMIC (I don't particularly care for their products), had a boost leak and DIDN'T try to hide it lol. Anyway, read the article.

As long as you can supply the proper fuel & tuning solutions, I would recommend the GT3071R. If your factory BCS can handle the boost you want (I recommend getting a wastegate spring as close to your peak boost you want to run as possible), I see no reason to run an EWG either, as I don't think you're trying to squeeze every last ounce of power out of your car, and they're loud as hell lol.

If you're not satisfied with your pump gas tune when all is said and done, THEN get a meth/water injection kit, as the main point of running meth is to advance timing & increase boost pressures safely. Although, I am skeptical about meth kits in general... only because if you set a meth kit to activate via XX MAF volts, or XX boost pressure, and it's a daily driven car, if the pump fails, line gets clogged ect, and you got WOT... well, you can see where I'm going with this. Your detonation buffer would not be there, but the additional timing/boost would be.... so, if you do go that route, take good care of your meth kit and check it often. Just my $.02

Hope that helps, good luck buddy! -Brandon
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Postby Rich » Tue Apr 14, 2009 9:14

I've got an ETS top mount, but it takes a while to cool down after heat soaked. Water/meth would help to bring the BATs down alot quicker. It's more of an insurance, as long as maintained properly (like you said). Thanks for the info on the 28 vs. 30....I think my mind is fairly set on the 30. Now I just need to get over the fear of popping my motor :)

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Postby roninsoldier83 » Tue Apr 14, 2009 9:14

Rich wrote:I've got an ETS top mount, but it takes a while to cool down after heat soaked. Water/meth would help to bring the BATs down alot quicker. It's more of an insurance, as long as maintained properly (like you said). Thanks for the info on the 28 vs. 30....I think my mind is fairly set on the 30. Now I just need to get over the fear of popping my motor :)


You're absolutely right about a meth/water injection kit bring down post-IC IAT's. Aside from intercooling (either air to air or water to air), meth/water injection seems to be one of the most popular ways to lower IAT's these days. Although, if meth/water were my only other option (no ethanol/E85 conversion available), for a 47 lb/min compressor I might consider just picking up a FMIC, if only for reliability purposes.

Now, it's true that a larger compressor will have lower IAT's making the same boost as a smaller compressor. For instance, a 47 lb/min compressor will not to work as hard/create as much friction (friction=heat) as a 35 lb/min compressor. Which is a large part of the reason why most people recommend that if you're trying to run uber-high boost pressures to just buy a larger turbo that was made to make those boost pressures, aka is in it's "efficiency range" at those boost levels.

Now, one thing that's often misunderstood is people think "if I keep the same peak boost pressures with the larger turbo, my post turbo/IC IAT's should be lower/the same". Depending on how much larger the compressor is, the difference in temps might not be all that drastic, but more importantly, a larger turbo that has the ability to HOLD that peak boost pressure longer, is ultimately going to be forcing more air through your intercooler, making your IC more likely to heat soak.

For instance, my current stock turbo makes around 19psi peak, but then tapers down to around 12-13psi at redline. You can look at my torque curve listed above to give you an idea of how linearly boost tapers off. Remember, torque is the force that is driving your vehicle, horsepower is only a calculation to show how well torque is sustained.

So, current= peak 19psi-------tapering------>12/13psi at redline.

^^^This is what my stock air to air IC (top mount) has to attempt to bring to ambient temps. For comparison, if I was to pick up a larger, lets say 49 lb/min compressor that had no problem holding boost longer, it would look more like this:

Peak 19psi--------tapering------->18psi at redline.

^^^At that point, even though my peak boost pressure might stay the same, I'm going to be holding higher boost pressures longer, which are going to be routed through my air to air TMIC, and because there's going to be considerably more air (after the initial onset of boost, as it won't be tapering as fast), the extra heat/friction is going to heat your intercooler to a greater degree... aka, more likely to heat soak, or I should say, heat soak "faster".

Now, while I think the GT3071R would be a great fit for the MZR motor, I do think that you will be limiting the turbo (not pushing it very hard at all), as well as your timing advance, in order to keep IAT's in check with your TMIC. Although, surely a meth/water kit would help in that department, me personally, I would rather run a FMIC. In case you ever wanted to up the boost/run more timing advance, a FMIC is also a nice knock buffer.

You would get a larger air to air surface area, along with a more direct airflow path, not to mention your IC wouldn't be sitting RIGHT on top of your motor lol. At least on a Subie the TMIC is somewhat behind the motor, and has a huge hood scoop in the hood to help with flow lol. Something to consider:

With the cash you will likely be spending on a meth/water kit, combined with the cash you could likely recoup by selling your ETS TMIC, you could probably buy a FMIC.... only, at that point, you never have to worry about a water/meth pump failing, no worries of possible long term corrosion from methanol, electrical/wiring malfunctions and you never have to fill a tank or worry about it getting low/running out of meth/water. A FMIC has no mechanical parts, nothing to "break" per se. The worst that could happen would be a hose coupler or something coming loose, and having a boost leak, not NEARLY as dangerous as a meth kit failing under full boost. Me personally, I would have more piece of mind with a FMIC. I can assure you, that if my car wasn't running on ethanol, I would have bought a FMIC rather than my APS TMIC.

Just my $.02 though. Either way, good luck buddy!
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Postby Rich » Tue Apr 14, 2009 9:14

I am fully against FMIC for the sake of keeping ECT down. Eric has demonstrated the effects of a FMIC blocking the radiator with ECT in the 220F range....normal cruising should be in the 180s. There is a Liquid-Air option out that I might consider....the front heat exchanger is much thinner than an Air-Air FMIC, and it maybe be able to be v-mounted with the radiator.

I've also thought about just running a spray rail around the TMIC, with water and CO2. I could mount it within the hood ducting and run the lines down the hood mounts.

I will of course consider all options when I'm finally ready to do all this. Thanks for all the great info Brandon!

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Postby roninsoldier83 » Tue Apr 14, 2009 9:14

You make a very good point there.... you've peaked my curiosity, I don't suppose Eric did any before/after logs in similar conditions? I never would have though a FMIC would have made a 40+ degree difference in coolant temps... wow.

The only things I could possibly think of to help with that (within reason), are maybe a lower temp thermostat? Playing with fan settings (assuming it's an option)?

I was taking a look at a FMIC over here:
http://www.therpmstore.com/images/Intercooler_Kit_Picture_large_pic1.jpg

I can DEFINITELY see it blocking a good bit of the radiator, but I never thought it would cause temps to shoot up 40 degrees... just seems excessive. I can definitely see your point though. There's always a trade-off, isn't there? :lol:
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Postby dommo_g » Tue Apr 14, 2009 9:14

Did your buddy dyno his Charger?

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Postby roninsoldier83 » Tue Apr 14, 2009 9:14

dommo_g wrote:Did your buddy dyno his Charger?


Yeah, he put down 340whp & 347wtq... due to the fact that his car comes rated at the crank at 425bhp & 420 ft-lbs, he seemed really disappointed. I didn't understand why, the SRT-8 only comes in an auto, which I assumed would have about a 20% drivetrain loss, and a Dynojet is fairly accurate on correcting numbers for NA cars, 340whp sounded spot on to me.

I actually referred him to http://www.cosrtoc.net a while ago when he bought the SRT-8.
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