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- SS MS3 GT
Yes... but the boost reached in each of those gears IS dependant on the sensor. Elevated boost levels + fooled ECU = dangerous afrs..
just speculating and trying to stir up some more ideas from others..(crazy)
Dh a/f accuracy.
- Thread starter laloosh
- Start date
Yes... but the boost reached in each of those gears IS dependant on the sensor. Elevated boost levels + fooled ECU = dangerous afrs..
just speculating and trying to stir up some more ideas from others..(crazy)
4th gear nad 5th gear boost patterns are generally the same. my boost in 3rd gear is the same as it is 4th 5th and 6th, unless my prosport boost guage plays tricks and reads stops at 19 no matter what, which i doubt lol
read the graphs and my descriptions.
4th gear pull from 3k rpm, mid to high 11s af ratio.
start in 3rd gear and floor it to redline, hit 4th gear and the a/f ratio in 4th will be 12.5-13.0, thats just not right.
on both pulls the ecu reads the same s***, the same boost is hit, the a/f ratio changes...the question is why
read the graphs and my descriptions.
4th gear pull from 3k rpm, mid to high 11s af ratio.
start in 3rd gear and floor it to redline, hit 4th gear and the a/f ratio in 4th will be 12.5-13.0, thats just not right.
on both pulls the ecu reads the same s***, the same boost is hit, the a/f ratio changes...the question is why
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- 2007 MS3
The obvious difference here is one is roll-on and the other is not. Under the two different conditions, the ECU may be referencing different maps. Rolling on is more likely to produce lugging, or possibly knocking, running flat out ripping through the gears, while calling for boost and power is not the same thing, so the ECU may decide that different afrs are needed.
well the results are scary at best.
on the commanded afr seems to actually go rich, the other 3 all follow each other almost exactly. here are the 3 graphs
3rd to 5th
4th alone
1st-5th
either im running out of fuel, or the dh is wrong. msd says the dh is very accurate in picking up the actual a/f ratio. So like i said either the dh is off, the stock sensor is a big pos, or im running out of fuel again cause im nowhere near reaching the commanded a/f ratio
on the commanded afr seems to actually go rich, the other 3 all follow each other almost exactly. here are the 3 graphs
3rd to 5th
4th alone
1st-5th
either im running out of fuel, or the dh is wrong. msd says the dh is very accurate in picking up the actual a/f ratio. So like i said either the dh is off, the stock sensor is a big pos, or im running out of fuel again cause im nowhere near reaching the commanded a/f ratio
Loosh you have to remember, at the temperatures your driving in, the car is going to add timing, increasing the AFR of your setup. Start datalogging the timing PID and see what you get. Do it over the course of 3 days since the temperature outside should have a variance.
The weird thing about this car is, at mid 12's, youre not having any issues with the car. If this was a mustang, the ****** thing would of blown a piston or rod by now. Im actually starting to believe the DISI motors dont have dangerous lean until 13 - 13.5 AFR.
The weird thing about this car is, at mid 12's, youre not having any issues with the car. If this was a mustang, the ****** thing would of blown a piston or rod by now. Im actually starting to believe the DISI motors dont have dangerous lean until 13 - 13.5 AFR.
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- SS MS3 GT
That is nuts. This car is like it is on crack..
At least your car isnt doing this:
Talk about frustrating... Everytime.. 4900rpm in 4th and 5th the boost drops and the power plumets with it.. Boost goes from holding 17-18 then DROPS at 4900 down to 13/14 and never recovers..
At least your car isnt doing this:
Talk about frustrating... Everytime.. 4900rpm in 4th and 5th the boost drops and the power plumets with it.. Boost goes from holding 17-18 then DROPS at 4900 down to 13/14 and never recovers..
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i did and its fine. the highest knock retard ive seen was about 1.2 and it didnt effect timing at all.
astraelraen
Member
My CX7 has been in the 12/1+ AFR since winter came. Obviously its a different car/engine tune, but its still basically the same engine. I don't think I've seen it drop below 10/11, even under heavy acceleration since.
It scared me at first, but its been that way since temps dropped below 40 and my engine hasn't blown up yet.
My only explanation is that colder air creates denser air which means more oxygen entering the engine. The ECU/fuel pump must not be able to compensate for this and creates a lean condition.
I don't know what "normal" timing is for these engines. But I've logged spark advance to see what it looks like as well under colder weather.
It scared me at first, but its been that way since temps dropped below 40 and my engine hasn't blown up yet.
My only explanation is that colder air creates denser air which means more oxygen entering the engine. The ECU/fuel pump must not be able to compensate for this and creates a lean condition.
I don't know what "normal" timing is for these engines. But I've logged spark advance to see what it looks like as well under colder weather.
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- SS MS3 GT
(yupnope) lol.. yeaa.. it was fine for a while.. then went bad, then the BOV cured it.. now its bad again.. Going to give the lil spring mod a try.
AutoXRacer
Member
Can't wait to see the results!!!
I hate to say it, but messing around with ECU wiring, map clamps, etc...will mess up your ECU/tuning.
Every time you cut a wire, shielding, etc you're changing the environment the ECU was designed to work in...
Thats why I'm sticking with bolt-ons and leaving the ECU alone... Once you start cutting wires, all hell breaks loose...
(not trying to start a fight, just stating my opinion)
I hate to say it, but messing around with ECU wiring, map clamps, etc...will mess up your ECU/tuning.
Every time you cut a wire, shielding, etc you're changing the environment the ECU was designed to work in...
Thats why I'm sticking with bolt-ons and leaving the ECU alone... Once you start cutting wires, all hell breaks loose...
(not trying to start a fight, just stating my opinion)
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A map clamp isnt going to affect his AFRs... the damn weather is doing it. I also think 12's is no big deal with a DISI motor because none of them have grenaded yet.
Ive logged in temps as low as -20 F and have never seen readings that have deviated from the commanded AFR ... about the only thing I have really noticed when logging in cold weather is that my throttle is limited to about 28% max opening ..
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- SS MS3 GT
Yea and im trying to stop being a douche.. I think everyone knows where I stand as far as the FP and got my point across
So... I went out and did driver's plug mod. Didnt really seem to help with my 4900rpm problem, but may have pulled a tad better up over 5k.
I went on lowering my boost and I think I have gotten rid of it. From what I can tell on the butt dyno, the pause is gone and it pulls through 4900 now rather than choking. It is also ALOT stronger over 5200 and is holding power past 6k..
I really just need to get on a dyno and work this s*** out.
I keep reading posts here and there from the last few weeks saying that driver is going to the dyno, etc, etc.. but havent seen any threads or results yet. Is he just keeping them on the DL or has he just not gone yet?(dunno)
