ludeowner

Hi guys,

I had just installed my M2 stg III ECU and M2 downpipe last week. I just wanted to run these boost patterns through you guys cause I'm wondering if I may have damaged a vacuum line in the install, or possibly have a vacuum leak anywhere beween the turbo outlet and intercooler inlet.

My boost pattern:

35 MPH ~3rd gear WOT
-10 PSI 2K-4K RPM
-12 PSI 4K RPM
-10 PSI 4K-7K RPM

35 MPH ~2nd gear WOT
-10 PSI 2K-4K RPM
-6-7 PSI 4K RPM
-10 PSI 4K-7K RPM


My previous mods before the DP and ECU install were intake, exhaust, and HKS SSBOV. With those mods I had a perfect boost pattern of 10-8-10-8. I dont think I ever recall doing the test from 3rd ear though, I always did it from 2nd. I also do not have a EBC or MBC, and I run the stock plugs (9's and 7's).

I just wanted to see if these patterns were normal. The test I did in 3rd gear is what got my attention, instead of the normal 10-8-10 pattern I see a 10-12-10 pattern. Also isn't the M2 ECU supposed to have a higher PSI? I did a real quick inspection of all intake hoses, vacuum hoses for the CRV & HKS SSBOV, and all couplers, clamps and tubes between the turbo outlet and IC inlet. I didn't see anything wrong, and when I revved the engine up while looking over the hood I didn't hear any hissing through the plastic hoses.

I am still worried about leaks from the Y-pipe and the flat plastic pipe (crossover pipe). Also for the part that connects the rear compressor outlet to the rear of the y-pipe, is that thing suppose to be clamped down? all I see is an o-ring around going into the hole and the y-pipe connects to the rear compressor outlet. I also see a smooth bolt, which I thought could be tightened, but from the top angle it didn't look like it could be tightened down with a wrench.

This weekend when I go to re-tighten all the DP bolts I will check the y-pipe and the forward and rear compressor outlets. But what do you all think about my boost patterns? am I just being paranoid? I feel like the high end is the same as before the DP & ECU mods...could I actually be losing power up top, or is that just me getting used to the MaD pOwAh!!!

TIA

ludeowner

I should also add that my vacuum is at 16-18 hg at idle (700-900 RPM), and that my car does not smoke while it is idling.

not sure if any of that makes a difference.

mecman

iTrader: (11)

You can see what is in my signature.

I get 12 PSI with my M2 Stage III ECU.

tgriesel

When it was installed in my car along with DP, CB and stock airbox with a K&N it was pretty much 12-10-12. It would sometimes hit 13 and it would trail off a bit after 5K rpms. When I installed the IC and CAI, I had to install a manual boost controller to keep it under 13. Tom

ludeowner

Hiya Tom,

I was hoping that you would find this thread

I suspect a leak from the rear of the y-pipe, or possibly even the BOV might be opened a little at boost. I'm wondering if it might be my main cat too? doesn't boost usually go down when the main cat gets clogged? I also haven't ruled out my autometer guage, but it was the same one that gave me the good boost pattern before these mods.

I am also thinking about what my next mod route will be. I can either go cheap and risky by getting a halman MBC and MP or expensive and safe with a hallman MBC and IC, radiator, AST. I've read of the people having good results controlling boost using a hallman MBC with a stock ECU and MP.

satman

I have the same ecu. I called M2 but they did not want to share to much exact info about how it is programed. What they would say was that they changed the pills when they install the thing to get 12.5 - 13 max boost and that the maps within the unit could not support a mid-pipe. The turbo system on these cars is very complex. Cont.

ludeowner

A lot of people say that M2 advises against using a MP with their ECU. But if people with stock ECU's are able to maintain 10 PSI with a MBC and DP, MP, CB, and intake, then shouldn't the same thing be possible with the M2 ECU?

The MP itself does not directly increase the amount of air. Indirectly though, it allows the turbos to spool up faster due to less turbine backpressure. And it is the faster spool up which makes the compressor 'inhale' more air. The only reason I would think that M2 ECU would not be able to handle a MP is if the fuel maps for the low to mid RPM range is leaner then the stock ECUs. And I doubt M2 would be willing to give up that info, since you mentioned it in the beginning of you post. I am willing to bet that the entire fuel map is richer then stock though, so I dont think it would really be necessary to ask M2 about that.

satman

So many hoses and valves, tanks, etc. No one seems to be really able to explain exactally what controlls what and when. I do know that it only takes one of the above to screw the whole thing up. I have also learned that changing the pills wont get the job done. I get 11-11.5-10 tapering to 8. That is kind of like sex with no orgasm.
Cont.

satman

My next move will be some manual boost controllers. Check out the post from damien. Near as I can figure he is taking some of the electronic (ecu) control out of the loop and letting manual user controlled pieces to get the job done. With this setup one should get the same boost in all gears without tapering off. The downside however would be air density. Cont.

satman

So in other words boost will change with the weather. If you got everything the way you wanted it on a hot humid day then later you ran it hard on a cool dry evening you will get more boost. Or a summer/ winter or altitude change would require an adjustment. So there would be some fiddeling but I feel the results would be worth it. Cont

satman

Or one could go with a standalone electronic unit. I have one but the adjustments are so complex I am just going to sell it. I think if one keeps notes The adjustments would be easy. If anyone has any advice on this issue PLEASE chime in. Sometimes I cant sleep trying to figure this thing out.

ludeowner

Yes, I had taken air temps into consideration, which is why I waited until night to do the tests instead of doing it during the day. I probably should have mentioned that I did the tests late at night at around midnight 1 am. It was pretty chilly, probably between 50-60 F (or whatever the weather was like midnight last night in the Solano county area. The cars engine temps never went over 185 F, even after I had driven the **** out of it for a good 2 minutes.

I'm guessing that maybe Tom (tgreisel) had last used the ECU when it was still cold out in NorCal, which was only about 3-4 months ago. I'm also guessing that he did most of his driving during the day, whereas I do most of my driving in the early morning and late evening (to-and-from work). Having thought about all that, I am starting to think that maybe I have a leak somewhere or that my main car may be clogged.

satman

Hey ludeowner pehaps we should all bug m2 till they give up their secrets. Their stuff is old tech anyway. Most around here have the power fc. I know it is richer and have emmissions results to prove it. The reason they gave me a no to the mid-pipe was that the wastegate in the turbo assy was too small. I have a mid-pipe sitting on a shelf but am afraid to put it on.

satman

Play with the pills a bit, plenty of info around here on that around here. I doubt your cat is clogged or you would not be seeing 10 psi at low rpms. In your area the pills may work well. In STL if you dont like the weather wait a while and it will change completely. If your normal driving range does not change altitude much the fine tuning CONT.

satman

should be easy. Here we have days that go from 65-98 this time of year. Good luck and if you learn anything in the process let me know.
Ned

tgriesel

lude: Based on your mods you should be getting the same boost pattern as I did if not a little higher. All cars are a little different but you should look for a 12-10-12 in 3rd gear. The 12 will tend to taper off as rpms rise, maybe down to 9 or so. Based on my experience, other gears produce slightly different boost patterns. I did not change the "pill" when I installed mine. I only did it when I installed the manual boost controller. When installing a midpipe with the M2 ecu, it is my understanding that boost can exceed, spike, creep over 13 psi which on 91 octane gas is getting close to problems. It also becomes hard to control boost with a stock (reprogrammed) ecu when you go to a full free flow exhaust. Tom

ludeowner

Tom,

My boost pattern is actuall the opposite of what you had described. From a 30 MPH roll in 3rd and at WOT it pegs at 10 PSI then at transition it goes to 12 then it dips back down to 10 PSI.

One thing I did notice though as I was admiring my exhaust note was that when I rev it up to 6K and let off the throttle my HKS BOV will sound off. But when I try to do it again, the engine feels like it is choking and when I let off the gas the BOV will not sound off. I can also hear some sort of air or wooshing noise from under the hood. The noise is something that I normally dont hear when driving the car or when I had first revved it up and let off the gas.

Could all that stuff just have to do with the air pressure not being able to stabilize in time? or maybe from the BOV not being able to recover in time? (BOV valve slow to close).

Thanks

ludeowner

Just wanted to let everybody know that I may have found the problem.

While re-tightening my DP bolts, I replaced the big BOV hose that connects the y-pipe to the BOV. The big vacuum hose had a crack down the middle...it needed to be replaced anyways cause it was hard as a rock.

The BOV recovers faster while I repeatedly rev the car to 5K-6K. And my car no longer feels like it is choking or gasping for breath.

Thanks to all who participated in this thread