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The stock GT4 ECU was setup for emissions, since we have Cobb and I'm a Cobb pro tuner (switching things to Dundon from my old company RK) we used the Cobb Accesstuner software to tweak things a bit. The Cobb Stage 2 OTS map did a little bit but didn't address the things we needed so we went after it ourselves!
These preliminary results are race headers and tune:
I'll update tomorrow with the torque graph, was trying to make it less confusing...
Dundon GT4 Race Headers and Custom Dundon Cobb Tune. 40+whp max and 28whp peak.
We're not quite done yet, want to try a few more things to remove the troughs in the curve both on the headers and in the tune... Once we're done with development I'll post up another thread...
Great results but as other said would really like to see the difference with no tune. My dealer is fine with headers but a tune is a no no. Either way can't wait to see the finished results and look forward to installing them on my car
We're not quite done yet, want to try a few more things to remove the troughs in the curve both on the headers and in the tune... Once we're done with development I'll post up another thread...
Would like to see overlaid dyno pulls, stock vs. headers, with no tune, headers being the only mod, stock PSE exhaust. I personally am not interested at this time in ECU tune, only want to install headers, if anything.
I think the stock ECU can adapt to headers just fine with no tuning.
Our dyno goes to redline because we are able to get the car there. We are not using a 4wd dyno to run the front wheels so the PSM is happy.
We have a PIWIS 2 tester and are able to put the car in "dyno mode" so we can run just the rear wheels. This is the CORRECT way to dyno these newer cars.
This is all with the stock sport exhaust.
We have not done any intake manifold testing yet. or T/B etc.
We have another set of headers to test as well as a few other things up my sleeve as always.
We know what and why those dips and peaks are there and how to get rid of them, just not sure if it can be make to work and fit in the car correctly with the space that is there.
Here is stock vs JUST headers
43lb ft 30whp @ 3650rpm
27lb ft 26whp @ 5000rpm
12whp @ 6400
16whp @ 7400
fueling is a little rich around .81-.82 lambda but the ECU is correcting it to this point which is safe to run. I would actually lean it out a little but it is ok.
Here is headers vs air filters
slight gains with the headers but still worth it.
8whp @ 5600
9whp @ 6600
Here is headers WITH air filter vs current tune. We are not done yet with the tune FYI
10 lb ft up to 3600rpm
24lb ft 20whp @ 4100rpm
22lb ft 20whp @ 4800rpm
12whp @ 5800
15whp @ 6500
21whp @ 6900
17whp @ 7400
Here is stock GT4 to current Headers, Filters, Tune
Our dyno goes to redline because we are able to get the car there. We are not using a 4wd dyno to run the front wheels so the PSM is happy.
We have a PIWIS 2 tester and are able to put the car in "dyno mode" so we can run just the rear wheels. This is the CORRECT way to dyno these newer cars.
This is all with the stock sport exhaust.
We have not done any intake manifold testing yet. or T/B etc.
We have another set of headers to test as well as a few other things up my sleeve as always.
We know what and why those dips and peaks are there and how to get rid of them, just not sure if it can be make to work and fit in the car correctly with the space that is there.
Here is stock vs JUST headers
43lb ft 30whp @ 3650rpm
27lb ft 26whp @ 5000rpm
12whp @ 6400
16whp @ 7400
fueling is a little rich around .81-.82 lambda but the ECU is correcting it to this point which is safe to run. I would actually lean it out a little but it is ok.
Here is headers vs air filters
slight gains with the headers but still worth it.
8whp @ 5600
9whp @ 6600
Here is headers WITH air filter vs current tune. We are not done yet with the tune FYI
10 lb ft up to 3600rpm
24lb ft 20whp @ 4100rpm
22lb ft 20whp @ 4800rpm
12whp @ 5800
15whp @ 6500
21whp @ 6900
17whp @ 7400
Here is stock GT4 to current Headers, Filters, Tune
Our dyno goes to redline because we are able to get the car there. We are not using a 4wd dyno to run the front wheels so the PSM is happy.
We have a PIWIS 2 tester and are able to put the car in "dyno mode" so we can run just the rear wheels. This is the CORRECT way to dyno these newer cars.
This is all with the stock sport exhaust.
We have not done any intake manifold testing yet. or T/B etc.
We have another set of headers to test as well as a few other things up my sleeve as always.
We know what and why those dips and peaks are there and how to get rid of them, just not sure if it can be make to work and fit in the car correctly with the space that is there.
Here is stock vs JUST headers
43lb ft 30whp @ 3650rpm
27lb ft 26whp @ 5000rpm
12whp @ 6400
16whp @ 7400
fueling is a little rich around .81-.82 lambda but the ECU is correcting it to this point which is safe to run. I would actually lean it out a little but it is ok.
Here is headers vs air filters
slight gains with the headers but still worth it.
8whp @ 5600
9whp @ 6600
Here is headers WITH air filter vs current tune. We are not done yet with the tune FYI
10 lb ft up to 3600rpm
24lb ft 20whp @ 4100rpm
22lb ft 20whp @ 4800rpm
12whp @ 5800
15whp @ 6500
21whp @ 6900
17whp @ 7400
Here is stock GT4 to current Headers, Filters, Tune
07-15-2016, 01:41 AM
Preliminary Results
