Got to 183whp - cant get more

[brn12345]

So I spent the day at the dyno yesterday trying out various map changes. I started with Shivs Stage 2 1.42b map and the car baselined at 181whp. I then did the following tests and in each case I started out with Stage 2 1.42b and did the stated modification:


T1: Leaned out Primary Open Loop Fueling by 3% to compensate for trims
T2: Modified the Intake VTC by advancing in the higher rpm range (see photo)
T3: Retarded ignition timing by eliminating the advance in the Knock Correction Advance table, basically removing 1.76 advance (see photo)
T4: Flashed Shivs Stage 1 1.42b map


Ok so the results, in T1,T2,T3 the dyno graph was a near mirror image of the baseline Stage 2 1.42b map. In T4 there was a slight gain uptop from 6750 to redline




At this point I am happy with the 183whp but what is bothering me is why the changes I made had no impact on the dyno results. I am starting to think that I ran into a bottle neck that needs to be resolved before more power can be made. I am thinking the up pipe and midpipe are the only stock pieces I am running so they could be causing a bottleneck. My next tests will be with mid pipe replaced.


Attached is a dyno sheet of the baseline Stage 2 1.42b and the best result I got which was with Stage 1 1.42b.

[Bahraini86]

Dyno looks good and you are making good amount of power. Your secondary cat cud be restricting some flow tho!

[Fast_Freddy]

You're planning on replacing the wrong pipe! The oem front (up) pipe is much more restrictive than the mid-pipe due to the oem cat in the front pipe. According to Nameless and Super Sprint the gains from replacing the mid-pipe are slight.

[s2d4]

Originally Posted by brn12345

T1: Leaned out Primary Open Loop Fueling by 3% to compensate for trims
T2: Modified the Intake VTC by advancing in the higher rpm range (see photo)
T3: Retarded ignition timing by eliminating the advance in the Knock Correction Advance table, basically removing 1.76 advance (see photo)
T4: Flashed Shivs Stage 1 1.42b map
.

Some questions if I may,

1. 4th gear?
2. What fuel?
3. 3% leaned out where?
4. Why the change with intake AVCS only? and also why the reduction?
5. Why did you you removing timing?

[FR-S Matt]

You need to change out your exhaust up front. Stock exhaust is restrictive.

[brn12345]

Originally Posted by s2d4

Some questions if I may,

1. 4th gear?
2. What fuel?
3. 3% leaned out where?
4. Why the change with intake AVCS only? and also why the reduction?
5. Why did you you removing timing?

1. Yes 4th
2. VP Motorsport 103
3. In all rev range in the 0.9 to 1.3 load range
4. Testing to see the effect of such changes. None observed.
5. Same as above

[s2d4]

Originally Posted by brn12345

1. Yes 4th
2. VP Motorsport 103
3. In all rev range in the 0.9 to 1.3 load range
4. Testing to see the effect of such changes. None observed.
5. Same as above

On 103, you should be able to add more timing without knocking, not sure why you are reducing them.

As for the 3%, it looks on the lean side between ~4900rpm to ~6500rpm.

The reduction in intake AVCS, this would take some playing around which I have not done as yet, perhaps try advancing and play with exhaust side as well since you changed the header which is more on the exhaust side?

[jamesm]

you adjusted the fueling targets to compensate for fuel trims? you should adjust maf scaling to eliminate the trims to begin with, or set the high af learning bucket to 61g/s so they won't apply in open loop. you shouldn't ever have to change the fueling targets if everything else is right.

[s2d4]

Originally Posted by jamesm

you adjusted the fueling targets to compensate for fuel trims?

What do you think is the reason why tuners change fueling target?
Some of the dynos/logs I've seen shows AFR of up to ~13.5 recently, do you think it is because they haven't scaled the MAF correctly?

[jamesm]

Originally Posted by s2d4

What do you think is the reason why tuners change fueling target?
Some of the dynos/logs I've seen shows AFR of up to ~13.5 recently, do you think it is because they haven't scaled the MAF correctly?

yes. fueling targets are just that: targets. they will be hit assuming that airflow estimation is correct (ve if sd, maf if maf) and fueling calibration is accurate (di flow rate, port injector scaling, latency, etc.). if the ecu is making fuel volume calculations using inaccurate values, the end result will be off and you'll see fueling error.

some folks change targets to hit the afrs they want to see. that's fine, but your just masking a fueling error issue, and you'll chase your tail until you resolve that.

[Grip Ronin]

you made 181 on the stage 2 but 183 on a unedited stage1??

[s2d4]

Originally Posted by jamesm

yes. fueling targets are just that: targets. they will be hit assuming that airflow estimation is correct (ve if sd, maf if maf) and fueling calibration is accurate (di flow rate, port injector scaling, latency, etc.). if the ecu is making fuel volume calculations using inaccurate values, the end result will be off and you'll see fueling error.

some folks change targets to hit the afrs they want to see. that's fine, but your just masking a fueling error issue, and you'll chase your tail until you resolve that.

I believe he is just running a drop in filter, would that warrant maf scaling? Didn't think it would deviate much from stock by just the filter.

[Ny Brz]

I was able to achieve 183 whp on my invidia catback and injen intake on the dynoet as well. When you free up the front pipes and overpipe you see more gains

[jamesm]

Originally Posted by s2d4

I believe he is just running a drop in filter, would that warrant maf scaling? Didn't think it would deviate much from stock by just the filter.

i think @mad_sb did some testing where he found the stock maf scaling to be pretty bad even with all stock components.