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A bit of knock. A bit rich AFR. Fine tuning w/ DSMLink (UPDATE)

EfiniX

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Joined
Oct 18, 2012
Messages
647
Location
portland, or
First off, I've got a thread on tuners right now because I can't upload logs here. Feel free to go there since this is just a copy/paste of the text. I'm really keen on getting some input from the community!

click

First off, thank you in advance for reading and lending a hand. I'm new to tuning turbo cars, but I'm a fascinated by the process and eager to learn. I'm also eager not to blow my car up, so helpful advice is always welcome.

A little history. '92 Galant VR4 w/ 4000mi on a new motor. Here's the relevant bits. The complete build thread is over on the vr4 org @ click

I've read the tech forum guidelines and all of the "verify this before posting" stuff is verified.

Engine:
BC1100 valve springs
3g revised lifters
264/264 Delta cam regrinds
new knock sensor

Bolt-on’s:
T3-T04 w/ .60AR
FP racing exhaust manifold
Fujitsubo Legalis R 3” complete exhaust w/ custom 2.5” downpipe
K&N filter w/ MAF adaptor
ETS intercooler kit
High-flow cat

Other bits:
Walbro 255 fuel pump
FIC 950cc injectors
Hallman boost controller
DSMLink v3
Innovate Wideband
Southbend clutch (TZ Kevlar disk/SS-Series 2200# pressure plate)

On to the good stuff....

I'm driving on a dyno tune right now and I've noticed a few things. One is a rich condition at a certain MAF value, the other is a small (but noticeable due to timing getting pulled) amount of knock.

I'm seeing knock under boost 100% of the time when my boost hits 20psi. Sometimes while I'm in third gear, I don't see enough to throw a CEL. Other times I do. 100% of the time I see a CEL in 4th gear. I see knock at partial throttle under moderate boost at a lower RPM. Just one or two counts, so again, not enough to light the CEL. Different cells in the timing table as well (from WOT).

So I did 3 WOT pulls, and a partial throttle 2nd gear pull. Here's my cursory observations.

1. The boost est. seems accurate, even though my gauge is progressively resting clockwise of 0 (need a new gauge).

2. I seem to be running a bit lean between 300-500Hz on the MAF

3. I seem to be running SUPER rich at 670-730Hz on the MAF

4. I'm seeing knock at WOT when my max octane timing table hits 2.2/2.4 load @ 4500 rpms. This is the same for all 3 WOT pulls.

Here's thoughts.

1. Get a new boost gauge and yay, my airflow seems accurate.

2. If this is an issue, adjust the MAFComp to richen up between 300-500Hz.

3. Adjust the MAFComp to lean out a bit @ the effected Hz. What should my target A/F value look like at this point in a WOT pull? Does it track ok, or am I running rich/lean elsewhere (which I guess goes back to #2)?

4. I have two choices here that I can see. I can either pull a degree of timing at a time in and around the affected areas, or I can lower my boost a bit. Which is the better choice?

Of course, i asked the tuner for his advice and he said "That seems that it is the same are we richened up before that was "lean" but is somehow now rich. 4500 is phantom knock when the knock control comes back on but you could grab the slider and pul 2* and see if it goes away...my money is on it not changing."

I have no idea what the first sentence means, but this seems like normal knock given that it's a low counts at higher RPM's + boost. I had phantom knock before the new motor and it was like 47 counts @ 3200 RPM's or something nutty like that.

Thanks in advance!
 
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EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
No responses here or on tuners, so guess what? I'm going to start tweaking things myself. Join me for the journey!

First, let's look at the problem I'm trying to solve. I've noticed that i'm running rich while building boost between 3000-3500 rpm's. I'm building up to about 10psi in this range.







I've noticed the MAFComp is between 600hz-800hz in each case, so I'm going to adjust my sliders from this:



To this:



My goal here is to richen up the mixture a bit around 350hz - 500hz so that my AFR smooths out a bit, then lean it out a bit between 600hz-800hz.

I'll go cruise and make sure everything logs happy, then do some more pulls. Next is tweaking the direct access settings. Then onto the knock after that!
 
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EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
and I'm applying the breaks. i've just noticed that my injector size is wrong (850cc instead of 950cc) in link. This is a setting from the tuner, so I'm going to get it back to them and back on the dyno to get it squared away. I imagine tweaking the injector size will knock the entire setup off.
 

EHmotorsports

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Joined
Sep 25, 2012
Messages
1,278
Location
Beaverton
it definitely will. I wonder why they keep changing it back to 850?
 

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
Well here's what the tuner said:

"1.5% to global and 120usec over the direct access table seems within tolerance. Realistically the global is all about fuel pressure at idle, the global deadtime is based on the injector latency offset chart in the Direct Access. It only affect idle and cruise though so it wouldnt indicate an issue at WOT. I have found almost all of the stock ECU numbers to "imaginary" unless there is a drastic issue with a fuel pump or something which it will point out in a hurry."

Since every tuning guide I've read talks about getting the injectors sorted out as a critical first step, I'm not really sure what to think. The car is kinda flat at low RPM's, but it's heavy with a big turbo, so maybe that's just how it's going to be. It screams at higher RPM's, but there's still knock and so far, very little information coming back from the tuner. For example I sent my last email 6 days ago and I've gotten no response.

we'll see where this all lands...
 

EfiniX

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Joined
Oct 18, 2012
Messages
647
Location
portland, or
And frankly, this DA fuel table looks very suspect.

Before:



After:

 

EfiniX

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Joined
Oct 18, 2012
Messages
647
Location
portland, or
And confirmed!!!

Turns out the fuel tables were actually EVO tables. The tuner is sorting it out with apologies. More to come when I get my adjusted DA configs back.
 

slugsgomoo

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Joined
Oct 16, 2003
Messages
3,776
Location
Tacoma, WA
the dsmlink forums will be the most useful for stuff like this in my experience, just as a thought, have you tried there?
 

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
Agreed. In fact, the link at the top of this thread takes you to the tuners site, where all of my logs and DMSLink configs are.

No responses /ubbthreads/images/graemlins/frown.gif

However my tuner is on it now and we're getting it squared away.
 

slugsgomoo

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Joined
Oct 16, 2003
Messages
3,776
Location
Tacoma, WA
NO.

Not dsmtuners, aka worthless ricer fanboy club... /ubbthreads/images/graemlins/banghead.gif

If you have a legit copy of ecmlink, go to: click

people there can actually help you and be useful.
 

EfiniX

Well-known member
Joined
Oct 18, 2012
Messages
647
Location
portland, or
My bad. read your post so quickly I guess I didn't really read it.

However, I do have an update of substance. I have an updated LIVE and DA file from the tuner w/ the proper fuel maps for my car and I did a pull today. Some noticeable differences. First, the DA Fuel and Timing tables are 100% different.

Old DA AFR table:



New DA AFR table:



Old DA Timing table:



New DA Timing table:



I backed the turbo off a bit and did a 3rd WOT pull and things felt MUCH better at the bottom-end. I'm spiking to about 23psi now, and settling around 20psi (before it was 26 and 23), and I'm still seeing a touch of knock along the RPM range, but things are much happier. Just a bit more tweaking and I think I'll be ready to rock.

 
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