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ECMlink holset airflow issue?

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jpmxrider489

10+ Year Contributor
2,410
146
Apr 4, 2010
pittsburgh, Pennsylvania
1). No boost, vac, or exhaust leaks.
Boost leak test. leak from 10psi is well over a minute. From 25psi to 10psi took 45 seconds. From 34psi to 25 took 16 seconds. I have the factory pcv with a check valve tested to 30psi and routed like factory. I two catch cans both recirculated back to intake pipe. The PCV and check valve does not go to any catch can.

2). Verify mechanical timing.
I do have aftermarket cam gears. Did not adjust them. They are on the car as they came out of the box.

3). Verify base timing
All good

4). Ignition system
New plugs and wires. Plugs are NGK BR8ES. Coil pack stress tested to 40k.

5). Motor health
Motor has 5k miles on it. Compression was 5 off across the board. Leakdown test was also good, just forget actual result numbers.

6). Basic throttle body adjustments.
Simultating Idle switch from TPS. 1g s90 tb with fiav delete. Keeping ISC

7). Compression ratio
8:3:1

8). Wiring and sensors
Everything is installed right and to my understanding setup correctly.

9). No DTC/CEL codes
None.

10). Electrical system
All good.

11). Base fuel pressure and injector values
42.6 and FIC 1650 HI-Z

12). Properly calibrated and configured wideband sensor
AEM wideband in front location. Simulating narrowband simulation.

13). Type of fuel
E85

Let me start off by saying most of the tuning here was done by someone that has a very well known appearance in the dsm community. The turbo is a 7 blade hx35 with a divided 12cm housing. Straight vband exhayst. Wastegate springs are 17psi. Boost is set with the aem tru boost. I believe it is set to 36psi but it is duty cycle and is set to 60. I know my global is set differently than what the calculator says. That setting is what my tuner said is needed.

My problem is the way airflow reads. Horsepower seems to be all over the place. Boost falls off hard.

Prior to this log, I was still getting 43lb airflow with 2 large boost leaks. Now they are fixed with no change in how the car felt or drove. Airflow is still 43. I know airflow reading is directly related to ve but it just seems off. All the other stuff under wot is good. WBfactor is low and boostest and actual is close.

Could this be maybe my EBC is actually set to 28psi but spikes up to 38 and gets control of it later in the rpm range to bring boost back down? I posted my blt test results above.

If the boost is falling off because of a leak. I would assume it has to be a large leak. I have no idea what it could be then.
 

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Do you just have boost source to lower port on the gate? I had a similar issue before and switched how it was plumbed and solved it. Like I said before lb/min is directly calculated off the VE table with speed density. By redline you are down to 80's for ve. I personally feel the 100% VE at 3,500rpm and it drops from there is not correct.
 
Do you just have boost source to lower port on the gate? I had a similar issue before and switched how it was plumbed and solved it. Like I said before lb/min is directly calculated off the VE table with speed density. By redline you are down to 80's for ve. I personally feel the 100% VE at 3,500rpm and it drops from there is not correct.

The wastegate lines are plumbed like the image I attached. The only difference is there ate two ports on my compressor cover so I cut out the extra T. You follow what i mean? My lines are pretty short as well and are equal to length. You can see the lines in this photo.

I'll get another idle log. But my sdairflowperrev was .32 I believe. I can adjust that cell to get it to read .26 and do the compft as well. But would that make my airflow read right uptop? I also thought at first the ve table looked odd. But since my wideband and boost looks even i assume it was good. What do you think i should do?
 

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I myself. Start with getting injectors set so VE is 100 around 5-5,500 rpm. Once you do that your global is going to change alot. And your lb/min will go up a lot. You can make boost est and real boost line up with injectors set wrong. Depending on cams and overlap your idle airflow per rev. Most likely is .35-.40 ect. I don’t concern myself with it much with aggressive cams. Long as STFT are within 5% at idle I’m ok with it. I always use injector duty cycle as sanity check. 70% IDC with 43lb/min only adds up to injector and VE table is wrong. The timing map and AF target map all look fine to me. I normally target 11.7 on e85 but 11.5 is fine too.I have only used boost solenoids with ecm link so I don’t know how to set it correctly for your car. That diagram is correct way to plum it.
 
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I myself. Start with getting injectors set so VE is 100 around 5-5,500 rpm. Once you do that your global is going to change alot. And your lb/min will go up a lot. You can make boost est and real boost line up with injectors set wrong. Depending on cams and overlap your idle airflow per rev. Most likely is .35-.40 ect. I don’t concern myself with it much with aggressive cams. Long as STFT are within 5% at idle I’m ok with it. I always use injector duty cycle as sanity check. 70% IDC with 43lb/min only adds up to injector and VE table is wrong. The timing map and AF target map all look fine to me. I normally target 11.7 on e85 but 11.5 is fine too.I have only used boost solenoids with ecm link so I don’t know how to set it correctly for your car. That diagram is correct way to plum it.

First let me say thank you for your input on my issue.
So here is a idle log. I changed a individual cell to make airflowperrev lower. I then got compft close to 0. I know my ISC is a little out of wack and will work on that as well. But my main issue is the airflow reading. The calculator in link says to use a global of-58. You say to get VE at 100 to find my global at 5500. But how specifically do I do that? From my understanding, the wbfactor determines how much I add or take away from a specific cell. In that cell that you want to be 100, it is at 93. So I would have to add 8. But the wbfactor says to -2. I am decent at working the idle/cruising portion on link. But when it comes to the WOT and adjusting global is when I get confused. I always used what the calculator said and went from there. But since on e85 and HIZ is also confusing me. It might not have much to do with my issue but just saying my understanding is limited. Also, that previous log was a finished result from a reputable tuner. I lowered the global to experiment, The airflow number went up a bit but wideband didnt match. I set it back to how it was.

Now to address the boost issue. I am starting to think it isnt a boost leak. I think the boost is set at what it falls off to like 28. I think the issue is actually spiking from 28 to 38. Reason I say that, if I lower the setting, say to 24, boost doesnt spike or fall off. Maybe I need to go to the next spring pack to control boost better.
 

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I will look at the log tonight. But to do it you build the VE table to read 100 around 5000rpm then. Adjust global so that wide band and target AF match. This will change your idle, cruise, everything. But it will get the injectors set correctly. I’m going to guess being your not at 100 that your global will need to go down. Wideband factor just tells you how close it is to target. Not that injectors are set right. I can make the WB factor line up and hit target AF with global all over the place just by manipulating the VE table. I am not sure about your boost issues but it appears to be you are figuring it out. Normally if a car overshoots boost with a BCS it’s because the duty cycle is to high early on and it will attempt to hit a boost level the car isn’t capable of making at that low rpm. Then when it does get there it overshoots.
 
Your Idle log looks 100% fine to me other then the ISC position. Get that to around 30 and all is well. I see you are targeting 15-17 degrees of timing at idle? What is the reason for that? I have found sometimes high timing at idle can cause the car to want to idle up some. I usually set it around 5-8 degrees at idle myself.
 
There is no way that housing is restricted to 45lbs.min. One thing I did see is your IATs skyrocket. On a 3rd gear pull, my IATs go up like 1 degree. Yours go up like 40 degrees. Check for compressor blade damage, clogged intercooler, and leaking at the wastegate. I had an airflow issue and it turned out to be a leaking wastegate flange. Look for black soot on the flanges.
 
Boost leak test. leak from 10psi is well over a minute. From 25psi to 10psi took 45 seconds. From 34psi to 25 took 16 seconds. I would assume that test would say that there is no intercooler clogg? My intercooler is vrsf and its 2.25 in and out and piping is 2.5. I cant imagine that being a big factor here. Is there a way I can smoke test the gates for a exhaust leak?
There is no way that housing is restricted to 45lbs.min. One thing I did see is your IATs skyrocket. On a 3rd gear pull, my IATs go up like 1 degree. Yours go up like 40 degrees. Check for compressor blade damage, clogged intercooler, and leaking at the wastegate. I had an airflow issue and it turned out to be a leaking wastegate flange. Look for black soot on the flanges.
 
I months ago went threw some logs with him and can confirm his SD table and lb/min is accurate. I am still unsure why its logging so low for the boost. I thought possibly lots of cam overlap.
 
At how much rpm are You seeing that airflow?
at 4700rpm at 38psi im showing 41lb/min and my omni bar, ecuboost, and boost est are good. But seems like anything over 5500 the boostest start to fall off while omnibar and ecuboost match pretty good. But at 7k my omnibar and ecuboost are at 27 and boostest is 21 while airflow is at 42/lb. Boost just falls off so hard up top.

I months ago went threw some logs with him and can confirm his SD table and lb/min is accurate. I am still unsure why its logging so low for the boost. I thought possibly lots of cam overlap.

I greatly appreciated the help brother. Im still at a loss here though.
 
I have a similar setup and am having a similar issue with my holset. I have never logged more than 45lbs/min yet was able to make 515 hp on a mustang dyno. Tuner told me he thinks my turbine housing is maxed out at 30psi but that doesn’t make any sense to me given the numbers I’ve seen others post with the same housing.
 
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Altitude and temp play a big role in HP. I also do not get to worked up over the lb/min to guess hp. Trap speeds in 1/4 mile is better estimate. I don't think his car was holding boost up top. Did you ever try something other then the aem tru boost?
 
Altitude and temp play a big role in HP. I also do not get to worked up over the lb/min to guess hp. Trap speeds in 1/4 mile is better estimate. I don't think his car was holding boost up top. Did you ever try something other then the aem tru boost?
I tried using ecmboost control but without change.
 
at 4700rpm at 38psi im showing 41lb/min and my omni bar, ecuboost, and boost est are good. But seems like anything over 5500 the boostest start to fall off while omnibar and ecuboost match pretty good. But at 7k my omnibar and ecuboost are at 27 and boostest is 21 while airflow is at 42/lb. Boost just falls off so hard up top.

/QUOTE]

7k rpms @27 psi kg should be around 49ish lbs/min , but it will be afected by ve and iats to, so multiply that 49 * (your ve at that point)
That means You should be around 85ish at ve to get that result on airflow , raise the boost to 30 and should increase to 45 lbs/min with dame 85ish ve or 52lbs min at 100ve .
How well calibrated is your airflowper rev?

7k rpms @27 psi kg should be around 49ish lbs/min , but it will be afected by ve and iats to, so multiply that 49 * (your ve at that point)
That means You should be around 85ish at ve to get that result on airflow , raise the boost to 30 and should increase to 45 lbs/min with same 85ish ve or 52lbs min at 100ve .
How well calibrated is your airflowper rev?
 
It seems low. Way back in the day when I had a HX35 I was in the 40's at 24psi 14cm t/s housing on an open manifold. Later on running the HE351cw, I'd see like 80lb/min at 40psi.

How much power is the car making? What is the trap speed at the drag strip. The old rule of thumb is trapspeed = 100+boost. So this thing should be trapping 138. If significantly low, you have lots of work to do.

I don't have time to read through every post, but If this is in a divided housing, using a t/s manifold, you are 100% restricted by the turbine housing. I ran this setup, both 14cm and 12cm on an open housing, and t/s. The T/S sucked. took 10psi more to make the same power. Fun experiment, go find a open t3 flange,and slide it in between the manifold and the turbine housing. See how it acts like that.

My guess is that you have 70+ psi of exhaust pressure, and it's floating the exhaust valves and blowing open the gate. If you want this to work, you need get better valve springs, and/or get a bigger th on it. .


Edit: I looked at a couple pics, this isn't a tune issue, it's 100% a mis matched combo issue. The 12cm t/s housing is a low rpm deal, but you have a large dia header, and a smim. That's all high rpm stuff. I think you need a new header, small dia runners, and short as possible. Forget the equal length bs. SMALLEST RUNNER VOLUME POSSIBLE. Next get a larger housing, I think there is 16, 18, and 21 housings. I'd probably look for the 18. It think they came on some h1c stuff, and should be cheap to buy. Then lastly, I'd pick up an evo 3 intake. EVEN IF YOU HAVE A 6 BOLT HEAD. Little bit of welding and they work. That's what's on my car, non ported, on a 6 bolt head - runs 9.90s@140+ on 34psi at 3100lbs. Probably need better valve springs too I'd guess - something with 90ish+ lbs on the seat if you are going to be trying to run 30+psi on a t/s setup.

Realistically, I think and intake change and a TH housing change would drastically improve the car.
 
7k rpms @27 psi kg should be around 49ish lbs/min , but it will be afected by ve and iats to, so multiply that 49 * (your ve at that point)
That means You should be around 85ish at ve to get that result on airflow , raise the boost to 30 and should increase to 45 lbs/min with same 85ish ve or 52lbs min at 100ve .
How well calibrated is your airflowper rev?

airflow per rev seems good. But I can change a individual airflow per rev but that is in just once specfic cell. Ill attach a log from today.

It seems low. Way back in the day when I had a HX35 I was in the 40's at 24psi 14cm t/s housing on an open manifold. Later on running the HE351cw, I'd see like 80lb/min at 40psi.

How much power is the car making? What is the trap speed at the drag strip. The old rule of thumb is trapspeed = 100+boost. So this thing should be trapping 138. If significantly low, you have lots of work to do.

I don't have time to read through every post, but If this is in a divided housing, using a t/s manifold, you are 100% restricted by the turbine housing. I ran this setup, both 14cm and 12cm on an open housing, and t/s. The T/S sucked. took 10psi more to make the same power. Fun experiment, go find a open t3 flange,and slide it in between the manifold and the turbine housing. See how it acts like that.

My guess is that you have 70+ psi of exhaust pressure, and it's floating the exhaust valves and blowing open the gate. If you want this to work, you need get better valve springs, and/or get a bigger th on it. .


Edit: I looked at a couple pics, this isn't a tune issue, it's 100% a mis matched combo issue. The 12cm t/s housing is a low rpm deal, but you have a large dia header, and a smim. That's all high rpm stuff. I think you need a new header, small dia runners, and short as possible. Forget the equal length bs. SMALLEST RUNNER VOLUME POSSIBLE. Next get a larger housing, I think there is 16, 18, and 21 housings. I'd probably look for the 18. It think they came on some h1c stuff, and should be cheap to buy. Then lastly, I'd pick up an evo 3 intake. EVEN IF YOU HAVE A 6 BOLT HEAD. Little bit of welding and they work. That's what's on my car, non ported, on a 6 bolt head - runs 9.90s@140+ on 34psi at 3100lbs. Probably need better valve springs too I'd guess - something with 90ish+ lbs on the seat if you are going to be trying to run 30+psi on a t/s setup.

Realistically, I think and intake change and a TH housing change would drastically improve the car.

Your reply is way above what I know and skillset. I bought the turbo setup as a kit from a reputable seller. I would like to keep the manifold I have becuase I cant afford anything else. I could swing a different turbine housing but does it have to be twin scroll since the mani is? Also how would I calibrate the other things. Also, I am new to racing. I have 6 passes ever. 4 on this setup and on the 4th my tranny went. So now im back to manal and running strong. But being fwd, I spun and finished at 14.1 at 120 twice in a row. I know its bad, please dont hate, im just learning as I go with little experience at the track. Do you have a link to the turbine housing to try? My head is built with crower springs but I dont plan on revving past 7500-8k.
 

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That's ok man, we all gotta start somewhere, and I understand keeping the manifold. In the future, just because someone seems reputable, does not always mean they put together great combos. I've had my 1g for almost 20 yrs, and it's over 700hp and runs 9's and I'm still learning.

Anyway, 120mph trap sounds about right for 400whp, which is what it looks like you should be making according to the airflow, but it's well below what I'd expect a HX35 on e85 setup to run with upper 20's boost.

I think the next thing I'd do is plumb in some way to measure your exhaust pressure. Can be as simple as an old pressure gauge, some brake line, and a piece of hose, or a more elaborate setup. My guess is really high back pressure.

What head is on this car? If you only want to go 7500-8000 you need a different intake. If you have a 6 bolt head, I'd be contemplating a stock 1g intake. If it's a 2g head, find a Evo3 intake for sure.
 
That's ok man, we all gotta start somewhere, and I understand keeping the manifold. In the future, just because someone seems reputable, does not always mean they put together great combos. I've had my 1g for almost 20 yrs, and it's over 700hp and runs 9's and I'm still learning.

Anyway, 120mph trap sounds about right for 400whp, which is what it looks like you should be making according to the airflow, but it's well below what I'd expect a HX35 on e85 setup to run with upper 20's boost.

I think the next thing I'd do is plumb in some way to measure your exhaust pressure. Can be as simple as an old pressure gauge, some brake line, and a piece of hose, or a more elaborate setup. My guess is really high back pressure.

What head is on this car? If you only want to go 7500-8000 you need a different intake. If you have a 6 bolt head, I'd be contemplating a stock 1g intake. If it's a 2g head, find a Evo3 intake for sure.

The 120mph speed was with the spinning 1st and 2nd like for a length of time. But It takes 2 seconds from 70 to 90 mph. In this log in 4th gear boost held steady but boostest is off. Could I take my 12mm hotside off and port it to 16 as well as the manifold to help this issue? Are we agreed its mechanical and not calibration issue? I could put a pressure gauge at the tailpipe? Plumb back pressure gauge where that is easily a reversible thing? Does airflow go only off of boost est? if so why dont they match?
 

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