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Discussion Starter · #1 ·
I installed an FMIC this weekend, pics are taken, writeup is in-process. I also I relocated the DV and eliminated some severe bends in the Turbo Outlet Hose. Throttle response is fantastic, and the FMIC looks killer.

Intake Temps are reduced from 60C peak to 50C peak.
Knock retard is reduced (improved) from 6 degrees average to 4.
A/F is improved from 13.2:1 to 12.8:1.
Timing advance is improved from 19 BTDC average to 22.

But there is no measurable increase in power (or torque) except at redline, and it's statistically insignificant (I've seen these upturns before - phase-of-the-moon dependent). If you look at the pink line on the graphs, MAF seems to be holding constant.



When I first installed the FMIC, boost dropped from 15 to 13 psi. A twist of the MBC brought it back to 15 psi. But within the "error bars" of the measuring process, there really isn't any difference between the three dyno plots below. Ambient temp is within 1 degree C on all three graphs.

WTF? I'm totally befuddled. How can you have measurably better IAT's, timing, and A/F ratio yet see no increase in power? Is this FMIC extremely inefficient, or is something else happening here that I can't pick up, or was I expecting too much? I'm beginning to think that there just aren't enough air molecules at 5800 feet...

Before FMIC, 15 psi max sustained boost in 3rd gear:


After FMIC, 15 psi max sustained boost in 3rd gear:


"In-between" FMIC, 13 psi max sustained boost in 3rd gear:
 

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This is quite normal, intercooler is NEVER giving you increase in power/trrque itself. Trick is that now you can without risking detonation increase boost of your turbo or charger. Intercooler is only preparing pavement for better (more) using of forced induction.
 

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It looks like the area under your curve has changed a little bit. Do you have a comparison of three consecutive runs with the SMIC vs. the FMIC?

I dynoed my car with the APR chip and stock SMIC at 172whp and 208ft lbs. The second and third runs showed drops in power. After installing bigger injectors and the FMIC my hp numbers were nearly the same but they stayed consistent for five runs.

Hmm, do you have two boost gauges? If your gauge is connected after the intercooler you are probably running way outside the K03 efficiency range. Try connecting before the intercooler and see where you are at. Maybe the K03 just isn't flowing as much air now that it's outside it's optimum boost range (maybe as high as 17psi now), especially at 5800ft.

Hey and where are the photos!!?
 

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Possibilities..

Crappy intercooler

Leaking intercooler

Your charge temps aren't beyond the stock IC's capacity (not likely since you scored more timing advance)

You're already at minimum best timing for your long stroke truck motor, or close enough that the road dyno can't detect the differences (this is where I'll put my money for now)

I'd recommend running more boost in the mid-range. I think it would be a tall order to expect any more horsepower out of that turbo at your altitude, but you should be able to pull out more torque in the mid-range.
 

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Discussion Starter · #6 ·
Nenad said:
This is quite normal, intercooler is NEVER giving you increase in power/trrque itself. Trick is that now you can without risking detonation increase boost of your turbo or charger. Intercooler is only preparing pavement for better (more) using of forced induction.
That makes total sense, but it still leaves the question that with better timing and better A/F - shouldn't I see more power? :???:

CRD99 said:
...Hmm, do you have two boost gauges? If your gauge is connected after the intercooler you are probably running way outside the K03 efficiency range. Try connecting before the intercooler and see where you are at. Maybe the K03 just isn't flowing as much air now that it's outside it's optimum boost range (maybe as high as 17psi now), especially at 5800ft.

Hey and where are the photos!!?
That might be a possibility. My boost gauge is hooked up to the intake manifold, same nipple that the DV uses. I like it there because it measures how much boost is in the intake tract. I'll see if I can find a spare "tee" and hook it up pre-IC...

Meanwhile dammit I'm installing the 42 lb injectors tonight... grrr....

Photos are in a friends' camera and they aren't downloaded yet.
 

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Sorry if I'm displaying my ignorance here, but wouldn't an IC's ability only come into play with the car in motion? While it's true that the FMIC isn't designed to improve HP, only to cool the air coming into the engine allowing for OTHER methods of higher hp, isn't the advantage of mounting in the front obtaining a quasi-ramair effect, which is effectively impossible on a dyno?

*shrug*
 

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Discussion Starter · #8 ·
pacent, Mac:

Thanks, makes sense. But first more fuel, then more boost. Then :beer: .

This comment I can certainly believe: "You're already at minimum best timing for your long stroke truck motor, or close enough that the road dyno can't detect the differences (this is where I'll put my money for now)"

Heh - heh - long stroke truck motor - should put it in an old Rabbit pickup... I bet I'd get some great 1/4-mile times... :lol:
 

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I would think a good FMIC would show more HP over a Heat Soaked Stock IC across most all ranges as your feeding the intake a cooler/denser charge.

Maybe not more then the intial cool first jump on the boost in the morning numbers...but as time and heat come into the equation......
 

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Discussion Starter · #10 ·
tonality said:
Sorry if I'm displaying my ignorance here, but wouldn't an IC's ability only come into play with the car in motion? While it's true that the FMIC isn't designed to improve HP, only to cool the air coming into the engine allowing for OTHER methods of higher hp, isn't the advantage of mounting in the front obtaining a quasi-ramair effect, which is effectively impossible on a dyno?

*shrug*
Totally correct but this is a "road" dyno using the VAG-COM and Ross-Tech Andy's "Butt-Dyno" dynpoplot4.xls. You can see the drop in IAT's - look at the orange line.
 

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intercoolers don't give you power.

they keep you from losing the power you already have by keeping your intake charge consistent under varying conditions.

it's a common misconception.
 

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Rusty said:
That makes total sense, but it still leaves the question that with better timing and better A/F - shouldn't I see more power? :???:
Only in case if you burn more fuel and air.
Your A/F ratio is now on rich side, but for better result it should go further, I would say 12:1 or 12.5:1 with full load even richer: 10.5:1.
And peak timing should be between 18 and 22 degrees, so you are on top edge with your's 22 degrees. Maybe to retard timing slightly, back on 19?
From temp point of view only, with -10 C degrees you should benefit 3% in power.

Are you on usual octane gasoline?
 

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CRD99 said:
It looks like the area under your curve has changed a little bit. Do you have a comparison of three consecutive runs with the SMIC vs. the FMIC?

I dynoed my car with the APR chip and stock SMIC at 172whp and 208ft lbs. The second and third runs showed drops in power. After installing bigger injectors and the FMIC my hp numbers were nearly the same but they stayed consistent for five runs.

Hmm, do you have two boost gauges? If your gauge is connected after the intercooler you are probably running way outside the K03 efficiency range. Try connecting before the intercooler and see where you are at. Maybe the K03 just isn't flowing as much air now that it's outside it's optimum boost range (maybe as high as 17psi now), especially at 5800ft.

Hey and where are the photos!!?
yeah this sounds correct.....the k03 can only make 12 psi or so at high rpm/flow rates even if the MBC is calling for more (15 psi). so its probably "pinned" (and it probably was before) but now you are pumping into the larger IC = more volume = possibly lower "saturated" pressure. this is offset by the cooler temps and higher timing advance so the power is the same. so you have two variables here....if you could have lowered temps 10C with the stock IC then you should have seen some HP.

what is the boost at the HP peak, is it the same or less?

the maf is pre-turbo so it only sees airflow and doesn't know that the turbo outlet temp is lower...only way to make MAF change is to cool the air entering it, raise boost (= more air drawn in) or reduce restrictions.

since your high-rpm MAF is the same it would seem to indicate that the turbo is "saturated".

Time for a bigger turbo. :)
 

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I agree with most people's replies here. The intercooler is simply changing the environment your car is dealing with. Everything should run better and allow you you to push the envelope further by increasing boost and timing to see better horsepower results without knock or detonation. If the boost has not changed with the intercooler upgrade you may not see a big change. I also recall most companies doing chip tuning would ask you if you have an intercooler as you will need different programming to account for it and utilize the better conditions created by it.

I just went to about every company I know of who makes intercoolers to see what each company publishes. Those who even mention details, are not ever qouting horsepower gains but only mentioning the cooling result, duration for cooled air to increase back to pressurized tempurate, and pressure drop or lack of. ABD was the only company I found who qouted actual dyno testing results but did not produce a graph.

Here is a cool link I found too thought it was a cool read:
http://www.turbocalculator.com/intercooler.html

I wish I had all my tuner magazines from way back when. I used to have some honda tuner mag which did a intercooler buyers guide and had all kinds of good technical test results which I didn't understand back then.
 

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If I have two IC's.....one cools better then the other, assuming the engine can make use of the denser air...that equals more HP.

On initial start up..both should be the same....but once they warm you get differences. Yes, the better one will not give more HP then the other did at initial start up before it warmed. But since the stocker warms up so quick, and stays there...except for a few minutes (when the stocker is cool) you are making more HP. (or put another way staying closer to the cool max of both) So as far as I'm concerned, it is making more HP..Daily real world been on the road awhile HP.

Adding a CO2 or Nitrogen mist will make HP, since your cooling it more then your ambient temps....unless you live at the poles! :D

But Rusty, sounds like you may have reached K03/Altitude constraints possibly. Dont know...I do know you'll keep plugging at it! :D
 

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another thing to consider:

intercoolers that are tested on a dyno prove nothing.

the only way to really figure out what's going on is road testing; when there's air rushing past the thing and it's doing its job.

on a dyno, even with fans in front of an IC, all you're doing is getting data as to how well it handles heatsoak, and as a result, getting an idea of how good a heatsink it is.

look at what happened with the infamous Forge Sidemount debacle.

they were advertising a certain gain they got from a dyno, but a few guys went out and did some road tests with temp probes. they discovered that the forge ICs were actually hurting performance.

all of the ones that were on sale on the classified section of the 'tex lost about $200 of their value over night. they couldn't GIVE them away after the results were posted.

forget about dyno testing to see any gains from an IC. find some temp probes and take it out on the road.

and remember (like i stated above), an IC won't give you power; it keeps you from losing what you've got by maintaining consistent charge temps for your car to work with, regardless of the environment it's in.
 

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Rusty,
it would seem to me, your're system was at least "1 run efficient" on the stock SMIC

I think you were probably not taxing it's abilties too bad unless you beat the hell out of it, or multiple WOT pulls. The altitude definitely plays a factor there I am sure. What are you're average dewpoints this time of year?

anyhow.....


The upshot is this, now you will have killer consistency, back to back...

on the dyno last month I only lost 1hp and 1lb of tq back to back across 4 runs 5 min spaced maxed..

I don't think adding boost will help that much now after seeing the static MAF
but what the hell, turn it up, see what happens, watch your timing, anything under 10 degrees retard is factory spec, I see 3 or 4 degrees lately, 80's and HUMID..I knew it was too good to be true..toulene here I come... :)

in short...

Where you thought you would gain you didn't,.... despair not, you no longer will lose ;)
(read in a loud preachy Jim Baker voice)

WTF am I saying? time for bed..


TJ
 

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Discussion Starter · #20 ·
Wow, lots of info to mull over, thanks everyone, I'll get back to you, but right now I am looking hard at the turbo. I thought the k03 was good to at least 15 psi and some people have quoted 18. I got a solid 18 lbs boost at 1000ft in 28F weather just this past Feb - it created enough torque to de-lock the torque converter. Scotty - your comment about 12 psi has my interest. Any documentation? *EDIT* - nevermind, I got it. 12 psi at high rpm/flow rates - that is known and expected.

I guess I need to learn how to read a compressor map... is this explanation a good one? http://www.dsmtuners.com/forums/showthread.php?threadid=128139

P.S. I put the 440's in last night. 440cc injectors at 2 bar base pressure and it idles as smooth as ever. More dyno runs today to iron out max fuel pressure...
 
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