Official no FMIC +METH, how well will it do?

[turboglenn]

Well, here's some pics of teh new IC pipes being built. I also went and had some tabs TIG'ed on the FMIC to mount it a little sturdier than before. NOtice how long and straight i was able to make some of the pipes. I figured while i was at it the less turns the better for airflow, and this already feels better than my old stuff for some reason, but it is 2.5 the WHOLE way, not just the UICP and turbo "j pipe" so to speak.

EDIT: One thing i did that's been eating at me to get done before pushing much boost is changin EVERY SINGLE IC pipe coupler to sillicone and usint good strong T-bolt clamps EVERYWHERE!!!! I feel confident tht i'll never blow off another IC pipe again!!!!!!!!

Here's me just getting started with the bumper off and IC mocked up with plumbers strapping... The pipe from turbo and upper pipe have both been started on at this point too

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Here's me doing some welding

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A little more progress, the upper is just dangling at the bottom, but is getting closer, the turbo pipe is through the hole in teh fender but not hooked up here

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Almost finished. I remounted teh DIS-2 while i was at it. Turned it lengthwise with the car.

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All done. Now i just have to make an apointment at the chrome shop to get them finished up and purdied out!

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I"ll get some pics of the AEM install here soon too. I'll run out and snap them i just hope the PC doens't restart when i hook the camera up like it did this time

 

[turboglenn]

Here's some more pics

Here's the AEM "in the dash" literally You can also see i put the stock gauges back in as well. I use to have gauges from an RS in there just because they had indiglo faces on them. I thought they looked cheesy after a few years :/ The knob on the column is the "fuel trim" knob you'll hear me refer to now and then. you Can also see the knock monitor for the J&S in the upper right of the dash/cluster. I like having as many things as i can within the sight of one glance.

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Here's a night pic ( it didn't come out the way i had hoped)

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Here's the tabs on both sides of the intercooler. A lot cleaner than how i use to have it ( i wont' talk about that )

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Here's the other side, i had to drill the hole off center because there was a hole already in the lower radiator support that was too big for the screws i was using. (no big deal)

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[jshuman]

I just want to make sure I am following this correctly. Here are a two main points from this thread that really struck me. Correct me if I am wrong please.

1. Meth/Water injection is beneficial on a larger turbo setup in the sense that boost response is increased due to the lack of an intercooler and piping.
-- The downside being that it is harder to achieve higher boost without knock.

2. A smaller turbo setup can possibly benefit from pre-compressor injection by way of shifting the choke flow and surge lines of that turbo's compressor map. This theoretically would make a smaller tubo behave as a larger turbo by not dropping off in the upper rpms, but without the lag.
--The possible downside of this is that the compressor wheel could be damaged by the meth/water particles as it is spinning at 100000 rpms. Although, this appears to be more speculation than fact.

Also, for those who are trying to aim the pre-compressor spray directly at the compressor wheel nut, is this an attempt to prevent damage of the comp. wheel?

Justin

 

[turboglenn]

Yes, you have all points pretty much correct. The lag difference on the big turbo is partially due to no FMIC and partially due to meth injected pre-turbo. And it's not that we couldn't stop detonation because we didn't get much. It was quick sudden bursts where the meth couldn't get flowing and cool in time that we saw knock. What was really bothersome to me was the high intake temps hurting power at mid throttle acceleration. The benefit was there's a miss my car gets when cruising at lean AFR's that went away with the hotter intake temps but is now back again since re-mounting the intercooler

We will be testing how far we can push a small 16g here very soon using meth pre-turbo. we will first see how much boost it will hold without it, then add it and see how much we can hold.. Then we'll start tuning and paying attention to airflow #'s

But to get back to some results. Having the FMIC is a dream after running without one for a few weeks! Intake temps are staying well below 100, even after a third gear pull they are only about 15-20* above ambient.

With the new straighter IC pipes I'm seeing some improvement in spool over the previous setup, but nothing like the straight pipe from the turbo to TB was giving me. Honestly the difference in power under 10psi is incredible how much i had lost with the "no FMIC" setup. When temps were in the 120-130's under light boost accel. (say 5-7 psi) i could actually feel the power drop off from what i can only suspect was heat buildup hurting the density of incoming air. Now that the FMIC is back on all that power has been regained. Since the AEM isn't hooked up for logging just yet i haven't gotten to pull any data logs (no point if i can't use them to further the tune)

But i tell you something funny that's off topic. I've got one of those license plate frames that has the scrolling words made up by LED's and the other day when i hooked it up, i programmed " two liter vette eater" into it and now every chevy redneck in a truck likes to ride my ass until i downshift to third and embarrass them I think solely because of that plate frame alone there was 2 grand prix GTP (supercharged) cars that kept getting beside me, taking off, then slowing down... I wasn't going to race them but the one got so annoying i slammed it in 2nd from a light and walked his ass... he stopped after that Some of the other things my plate says (it has 5 things it can store in memory) one says what i wrote above, then there's "one fast GS-T" - "can you keep up??" - "my pitbull is smarter than your honor student" and the last one is "got lag???" I think I'm going to change the 1 fast gst and the pitbull one to different things... I'd like to put "pony killer" in one of them to mess with the mustang guys a little


EDIT: the one thing i'd like to do is to get back to the dyno after all my testing and see if i can not only improve on the #'s i got on the same boost level when i go back, but i'm REALLY hoping i can use the meth, then tune to the best of my ability to crank out 425 daily driven horsies A new dyno sheet will be here by mid summer. I want to dyno in the heat just to see how effective the meth/water can be on hot ass days like we get around here where the humidity is almost the same as the temperature

 

[dsm-onster]

Now, now. Stop badgering the natives

It's very interesting to see you go back to the intercooler and why. You've very thoroughly proven that water injection AND a FMIC is a fantastic combination.

 

[jshuman]

Oh and I forgot to thank you for putting the time and effort into all of this testing. This has been one of the best threads I have read in a long time. I've learned a lot of very useful info out of it, and I cant wait to see some future results. Great work

Justin

 

[matthewdesigns]

I couldn't have said it better. Great thread with a tremendous amount of information. I'm especially keen on seeing results with your friend's 16g. I've got an Evo316g/Dejon big smic and would like to kep it that way, and this thread has gone a long way to helping me understand how to safely make more power with h2o/meth injection.

Thank! Matthew

 

[airmail96]

I have been reading this thread little by little all day and I must say I have learned a great deal thanks to your testing. Thanks again for the great testing and keeping us constantly updated through it all. Def. gives me some ideas for gonig total sleeper using a supra side mount, a 50 trim and some meth/water.

 

[turboglenn]

I have been reading this thread little by little all day and I must say I have learned a great deal thanks to your testing. Thanks again for the great testing and keeping us constantly updated through it all. Def. gives me some ideas for gonig total sleeper using a supra side mount, a 50 trim and some meth/alchy.

Glad to hear you got a good read and learned some things from this! The more people that chime in, the better i feel about doingthe test and posting the results.


Your setup described above sounds perfect for a daily driven sleeper with the potential to smoke some vette's

 

[H82lose91]

Im out of town right now but when i get back tuesday im going to try and get my trans broke in. If things are shifting nice and smoothly i might hit the track friday and see where my POS is trapping. Should give a good idea of how much power shes making. As long as the afr is dialed in she'll be ready to hit the dyno.

 

[turboglenn]

We put the pre-turbo nozzle on the S16g car today. His turbo is so worn out, it has about 3-5 mm of in and out travel on the turbo shaft (bad!). But the wheel is in great shape so we snapped some pics. Now we're going to start testing, and since it is beat anyway, we're not concerned about the turbo taking a beating. After it's destroyed we will be doing a bastard 20g build on it's frame

I't time to see if we can really improve airflow with this turbo and a bit of water/meth mix! Since the logs will be from DSMlink all of you should have less trouble viewing them as well.

TEsts, logs and more to come... should i start a new thread for this test anyone?????

Well, all i can say is FREAKING AWESOME RESULTS SO FAR!!!!!!!!!!!!!!! Seeing an average of 30more horses using DSMlinks HP estimate. I know it's not the most reliable HP reading, but when it was averaging 260-265HP on the same boost (20 psi) after adding just an 2 nozzle pre-turbo brought the reading up to 295 and intake temps were around 60* F, that at least says something positive (boost stayed the same since it wasn't maxed out yet i am guessing, but there was no increase in boost levels at all so far)..I was thinking he was letting out o fsecond early because it was going by so fast, but after looking at the tach move like it was, there's definatley more than a hint of improvement already and we havn't even tuned for the added meth that's made the car pig rich yet either!!!!!!!!

Logs will be up later tonight!!!!!!!!!!!

It just keeps getting better. No more boost still @ 20psi, and just leaning it out to 11.7:1 (previously we had a perfect 11:1 tune on it at WOT that made the 265hp on dsmlink). Newest numbers on link are showing 302hp.

Logs are still coming ( he's emailing them to me from his house ) I will post them as soon as i get them.

 

[dsm-onster]

If it helps, the small16g cmpressor map peaks out at around 38lbs/min at 20*C and at an atm I don't know. I've seen 36 lbs/min with this turbo at sea level and 71*F intake temps (at the airfilter).

You'll have to push it to a point where boost starts dropping off. For my current setup that was anything after 20ish psi. Since water injection pre-turbo should broaden the map, you should see more airflow at this point and boost may even hang on longer higher in rpms.

A definatl, noticable increase in power. Usually injecting after turbo doesn't cause a noticable increase in power itself, unless the tune is botched. You get the power increase from retuning leaner, more timing, and higher boost. So either he's got a knocking tune without injection, or pre-turbo injection is exhibiting a distinctive advantage !



Regardless, it sounds like there's atleast that same reoccuring trait of earlier onset of boost:

I was thinking he was letting out o fsecond early because it was going by so fast, but after looking at the tach move like it was, there's definatley more than a hint of improvement already and we havn't even tuned for the added meth that's made the car pig rich yet either!!!!!!!!

Can we have some non-injection logs, too??? (I'm all giddy inside. I may not sleep tonight.)

 

[jshuman]

That is really exciting! I wonder about timing being pulled before the addition of the meth as well. But if that is not the case, then those results are really impressive. Are the logs posted anywhere?

I have been thinking about this thread a lot the past few days. I have the hyperdrive digital alcohol injection system on my dsm. Its a fully adjustable progressive kit that is made to use denatured alcohol. I am about to start retuning and I am going to see how far this can take me. It just made me start thinking that the effects of pre-compressor injection has been discussed for small turbos and large turbos, but not midsized turbos (like my pte 50trim). Do you think midsized turbos like that stand to benefit much from pre-compressor injection?

 

[turboglenn]

There was no timing being pulled on his tune, it was about 11:1 exactly eveywhere through the RPM
s at 20psi. THe boost is still at 20 and the only thing that' been adjusted so far is the global fuel setting to lean it out. (at most his car pulls aa degree and a half ...seen it do three when we leaned it out once)

We just installed it today and i didn't have time to tune, so he took off. He got his laptop and started logging and then pulled some global fuel out and the results are in the logs, i just need to upload and link them up.

AFter teh pre-tubro meth he is complaing of some knock now in first gear and sometimes when downshifting into third and hammering on it. I'm thinking this is not detonation but yet another noise from the motoe as he had the 3rd gear downshift knock before this addition.

I know how perfect his tune was because i tried retuning it to squeeze a few more degrees of timing out of it and only got 2 degrees, which i removed to keep avoiding detonation. His setup is clean, well taken care of and very well and reliably tuned. This improvement is phenomenal!!!!! I am working on dowloading the logs now

The gains are leaps and bounds over what i saw on my car wihtout the intercooler and having pre-turbo meth. THe guys name is drdouglas on here, look up his mods if you want. But it's just a simple well put together s16, big FMIC, DSMlink, 255, 720's, devils own W/I and some the supporting mods, it's a combo that performs very well already

Here's a previous run, this on a 16g ~20psi (it spikes 21-22 then falls to 20 fast) and running w/i 50/50 mix with an M5 nozzle at the TB. 11:1 target AFR
http://members.cox.net/50reasons/run03152008-13.dat

Here's the same setup with the addition of a second M2 nozzle pre-turbo, no change in tune
http://members.cox.net/50reasons/preturbonochange.dat

Here's Another pull on the new setup with fuel backed down to lean out what the extra meth added in.
http://members.cox.net/50reasons/leanedout.dat

The logs speak for themselves, stay skeptical or believe it's up to you

~264 to 303.6 Of course they are DSMlink #'s but it still is a unit of measure, even if a bit inaccurate compared to a dyno, i would bet at least as accurate and reliable as a G-tech.


dsm-onster - as for "no injection logs" well those wouldn't be very fun as I've been in the car when the meth is off and there's no where near 20psi and keeping this kind of timing without at least the base kit injecting at the TB... we've got a ton of "no pre turbo injection" logs to post though, so if you want em, just name how many. This car is very consistent, very powerful for such a simple setup and gives respect back to mildly modded DSM's IMO. Just let me know any info you want I'm sure i can get or the owner would be glad to share!

That is really exciting! I wonder about timing being pulled before the addition of the meth as well. But if that is not the case, then those results are really impressive. Are the logs posted anywhere?

I have been thinking about this thread a lot the past few days. I have the hyperdrive digital alcohol injection system on my dsm. Its a fully adjustable progressive kit that is made to use denatured alcohol. I am about to start retuning and I am going to see how far this can take me. It just made me start thinking that the effects of pre-compressor injection has been discussed for small turbos and large turbos, but not midsized turbos (like my pte 50trim). Do you think midsized turbos like that stand to benefit much from pre-compressor injection?

Sorry i missed your question in this post earlier. I definately think there's an advantage to pre-turbo meth on mid-size turbos. Mine is only a hair larger than yours at a 57 trim t3/4 hybrid and even after putting my intercooler back on i'm keeping the pre-turbo injection. There's not one main advantage to pin point, but all the little gains together make a nice noticeable difference in both spool and overall power. Im geting so use to higher power tunes lately that my once daily conservative 19psi on pump is no longer satisfying after several dozen 23-25psi blasts down the back highways late at night during these tests.. I've been as giddy as school girl with all of this and i just keep coming up with new ideas to test and new hopes of found horsepower and increased MPG's Oh what it is to dream!

 

[romeen]

Good stuff Glenn!

I was unable to open the log files (I suck at computer stuff ) I got a pretty good idea of what is going on since the pre-turbo nozzle was added. But can you briefly summarize for me what kind of results he was seeing with just the M5 pre-TB nozzle?

 

[turboglenn]

He was seeing a good 20-22 psi with full advance from the ECU tuning the fuel with DSMlink and using it to add a degree or 2 of timing in the mid range.

All you have to do to view the logs is download the DSMlink software and install it, then the logs will load automatically.

Man, people seriously need to post more. I keep finding myself in the newbie section, looking for new posts late at night, I know you guys/gals are lurking + thinking, so why not make a post??

 

[2gGSX]

The airflow doesn't seem to be changed through any of those logs which is a little different from what I was expecting.

I know this is asking a lot, but have you considered moving the extra nozzle post-turbo and having it work as a "normal" nozzle in order to serve as a control? A third gear pull after letting the car cool off before changing the position of the nozzle and another pull (after the car is cooled again) along the same stretch of road after changing the position of the nozzle would be ideal, if you two were up for it.

 

[turboglenn]

We have one nozzle as control and on my setup i've not found too much diffence from anywhere between the BOV and immediately post turbo. Pre-tubro changes the air and changes things in a great way. I Suspected there would be no change in the reading at the MAF from the beginning since the change in air density is taking place inside the turbo after the MAF and i was right(so far) . It MAY pick up once the peak efficiency of the turbo is reached, but i kind of doubt it.

The vaporization of the water and methanol is what's providing the extra oxygen molecules, so I'm doubting it will EVER be seen at the MAF. I'm only partially convinced that it can be seen in any other way than actual performance, much like nitrous. With the vaporization of liquids containing oxygen , you will gain oxygen, and from it's point of entry, none of it is monitored by the engines sensors, except for maybe a change in IAT readings. But in water meth injection we have extra fuel as well, plus the benefits of water which are way beyond my explanation. I wish i was smarter when ti comes to that stuff

Once max boost is reached I'm fairly confident that a change in overall pressure holding abilities of the turbo will increase . And possibly a change in gm/sec consumption, but somehow i think it will remain elusive.

I have talked him into tuning to the same PSI on the M5 at the TB alone to baseline everything so we will see how much of it comes from the pre-turbo and how much comes from the tune and TB injection... I think I'm going to talk him into more meth/water soon too...we'll see, if his nozzles don't do th Job I'll throw some of mine in his car as long as he's willing. He's a good guy and ready to make some power, but I'm not going to push his motor past what i think's safe so we'll see what we can make and still be in my eyes "daily driven reliability" meaning you beat it everyday every time you drive it and it lasts!

Hopefully only good thngs are to come... I'm hoping i will convince myself to step down to something farily small for a large fat powerband on a some what smaller turbo.

 

[RipperXX]

Guessing water on a GM MAFT setup would be bad huh?

 

[2gGSX]

We have one nozzle as control and on my setup i've not found too much diffence from anywhere between the BOV and immediately post turbo. Pre-tubro changes the air and changes things in a great way. I Suspected there would be no change in the reading at the MAF from the beginning since the change in air density is taking place inside the turbo after the MAF and i was right(so far) . It MAY pick up once the peak efficiency of the turbo is reached, but i kind of doubt it.

The vaporization of the water and methanol is what's providing the extra oxygen molecules, so I'm doubting it will EVER be seen at the MAF. I'm only partially convinced that it can be seen in any other way than actual performance, much like nitrous. With the vaporization of liquids containing oxygen , you will gain oxygen, and from it's point of entry, none of it is monitored by the engines sensors, except for maybe a change in IAT readings. But in water meth injection we have extra fuel as well, plus the benefits of water which are way beyond my explanation. I wish i was smarter when ti comes to that stuff

Once max boost is reached I'm fairly confident that a change in overall pressure holding abilities of the turbo will increase . And possibly a change in gm/sec consumption, but somehow i think it will remain elusive.

I have talked him into tuning to the same PSI on the M5 at the TB alone to baseline everything so we will see how much of it comes from the pre-turbo and how much comes from the tune and TB injection... I think I'm going to talk him into more meth/water soon too...we'll see, if his nozzles don't do th Job I'll throw some of mine in his car as long as he's willing. He's a good guy and ready to make some power, but I'm not going to push his motor past what i think's safe so we'll see what we can make and still be in my eyes "daily driven reliability" meaning you beat it everyday every time you drive it and it lasts!

Hopefully only good thngs are to come... I'm hoping i will convince myself to step down to something farily small for a large fat powerband on a some what smaller turbo.

None of that proves whether or not the fact that the nozzle is pre-turbo makes any difference still. You would have to run the M5 at the TB to baseline, and then move the M5 from the TB to the pre-turbo position to show that there's a tangible difference.

 

[dsm-onster]

Yes it does . There was post turbo injection in the first log. Then the second and third there was post turbo and preturbo injection. The only difference is the introduction of the preturbo injection. Dsmlink shows a clear hp increase injecting preturbo without a retune: 30hp difference. After the retune there was an increase in 10 peak hp. There is a 50hp increase at 5K between not using preturbo injection and after using it. The powerband is GOBS wider.

There is more water/meth injected with the 2nd and 3rd logs. But an increase in total water/meth flow usually shows no increase in performance. Yet, we see a distinctive power increase and a broader powerband with more total flow here between the 1st and 2nd log. The injection pre-turbo clearly gave that power increase.

We have one nozzle as control and on my setup i've not found too much diffence from anywhere between the BOV and immediately post turbo. Pre-tubro changes the air and changes things in a great way. I Suspected there would be no change in the reading at the MAF from the beginning since the change in air density is taking place inside the turbo after the MAF and i was right(so far) . It MAY pick up once the peak efficiency of the turbo is reached, but i kind of doubt it.

The vaporization of the water and methanol is what's providing the extra oxygen molecules, so I'm doubting it will EVER be seen at the MAF. I'm only partially convinced that it can be seen in any other way than actual performance, much like nitrous. With the vaporization of liquids containing oxygen , you will gain oxygen, and from it's point of entry, none of it is monitored by the engines sensors, except for maybe a change in IAT readings. But in water meth injection we have extra fuel as well, plus the benefits of water which are way beyond my explanation. I wish i was smarter when ti comes to that stuff

Once max boost is reached I'm fairly confident that a change in overall pressure holding abilities of the turbo will increase . And possibly a change in gm/sec consumption, but somehow i think it will remain elusive.

Glenn, if you cause air to be more dense suddenly (read intercooling/aftercooling), then the compressor has to spin more quickly to maintain the same boost. Thus it draw in more air and your maf counts that increase in airflow. The same applies here, more density should show in more lbs/min reported by the maf.

The vaporization of water does not render an increase of usable oxygen content in the aircharge. O in h2o does not dismember itself as the h2o vaporizes. That would take heat beyond modern technology . There IS however a usable oxygen content in meth. But not very much.

I see 38 lbs/min in 1st gear in the 3rd log. I see 35 lbs/min in the first log in 1st gear. This could be from throttle modulation. But it looks like there was no wheelspin beween both. . . This is GREAT! stuff showing there.

However on average, there seams to be a 1 lb/min increase throughout the logs after preturbo injection. But, the turbo is simply not pushed to the limits of its airflow yet. So we don't know if there is a "widening of the map" as of now.

The idea of wet compression (preturbo injection) is to see more airflow. But, seeing and FEELING a clear increase in engine output is enough alone to convince me to inject preturbo. I personally think there are several things happening to feel and show such in increase in power. First is spool speed because the compressor is working less to compress the air. Second, is the air density increase: 1 lb/min increase thoughout the logs. That 3 lb/min inrease in 1st gea maybe an aberration. But he's AWD so I hope he wasn't lifting in the first log . Third you're powerband is just plain broader. Rediculously broader!

What maf is he running? The logs show BOOSTEST dropping off greatly. The maf is not calibrated or is being overrun. If he's running a stock 2g maf I doubt both, but a hacked 2g maf would output that signal if not calibrated.

 

[turboglenn]

All the baselines were done with the M5 TB it's been on there since before i met the guy.

Good info in the above post. i guess i crammed too much in my head when reading about it and got some of it confused maybe. All i know is it works

 

[2gGSX]

Yes it does . There was post turbo injection in the first log. Then the second and third there was post turbo and preturbo injection. The only difference is the introduction of the preturbo injection. Dsmlink shows a clear hp increase injecting preturbo without a retune: 30hp difference. After the retune there was an increase in 10 peak hp. There is a 50hp increase at 5K between not using preturbo injection and after using it. The powerband is GOBS wider.

There is more water/meth injected with the 2nd and 3rd logs. But an increase in total water/meth flow usually shows no increase in performance. Yet, we see a distinctive power increase and a broader powerband with more total flow here between the 1st and 2nd log. The injection pre-turbo clearly gave that power increase.

I've had a 30 hp difference in DSMLink's estimation from mild heat soak, just to show how big a difference intake temps can cause. How can you say injecting an extra 40% water/meth gives no increase in performance? It's not like he was flowing so much water/meth that adding more would have gave minimal benefits--a M5 nozzle at 150 psig is only 385 cc/min. There is absolutely nothing that definitively shows that the gains were caused by the M2 being pre-turbo.

You yourself stated that the MAS should still eventually see more airflow from the pre-turbo injection if it is indeed working according to your thinking. Between the first and second log, peak airflow changes by ~7 gram/sec. Between the first and the third, there really isn't a change in peak airflow at all short of what looks like a boost spike in first.

The test I am running suggesting would actually provide some evidence that the pre-turbo placement is what is causing this change. I mean hell, how do you run ANY experiment without some sort of control? I'm not trying to downplay what you're doing as I think it's great you've got the initiative to actually go out and do testing--that's great! But, adding a control would make your results ten-fold more credible.

What maf is he running? The logs show BOOSTEST dropping off greatly. The maf is not calibrated or is being overrun.

BoostEst is only supposed to match boost at 100% or peak VE and 70*F intake temps, and thus is supposed to be dropping off. You are right in that it's off though, but you would have to log MAFRaw in order to change anything. It needs a -10% correction at whatever MAFRaw is at 5000 RPM it looks like, based on the second log.

 

[turboglenn]

He's running a 2g MAF, I'm not sure why it's showing issues. Is there a way we can calibrate it or anything?

OUt of all the logs run with the M% at the TB, we've enver seen that type of HP reading in DSMlink.. The best we ever did before was 283 with higher boost on a 30* night. Yesterday was 60*'ish

 

[2gGSX]

You calibrate it the same way you would a MAFT setup. Jeff's page has the details http://www.jeffgst.com/gmafcalibration1.html

It's reading higher than you'd expect, which is sometimes indicative of a boost leak somewhere.