[M5Gator]

So some of you may have seen my original post on my stock dyno run which I was pleased with here Stock dyno runs.

Since then I've had SuperSprint headers and x-pipe installed and had a chance to get a post mod dyno done. I must say, I was expecting nearly double the gain (or more) from everything I've read and results of others. I realize desperately need a tune, but I was running WAY rich even before the headers as seen in the graphs and numbers below.

Stock whp 335 torque 324
Headers/x-pipe whp 345 torque 321

Maybe expecting 20-25whp gain was a bit much, but it also seems I lost a little mid range power and torque. Will a tune fix this and significantly improve the numbers or is this expected? I'm hoping advancing timing and correcting AF ratio will get me the extra 10-15whp I was hoping for.

Weather was hot and disgusting both times (98-100deg) with a bit more humidity on the header dyno runs but the #s are corrected anyhow.

Any recommendations on software tune for headers is appreciated! Do any of the companies use run files to create custom tune? Also looking for something that doesn't jack up the throttle response so much that makes it tough to daily drive. Thanks guys :cheers:

Numbers from best headers/x-pipe dyno run:

RunFile_006.drf: 98.48 °F 29.85 in-Hg Humidity: 42 % STD: 1.05 Average Gear Ratio: 52.86

s RPM x1000 hp ft-lbs Air/Fuel
0.37 2.20 15.98 38.06 14.62
0.88 2.40 142.94 312.80 13.47
1.33 2.60 157.27 317.69 12.77
1.77 2.80 167.51 314.21 13.56
2.21 3.00 183.00 320.39 13.63
2.65 3.20 193.47 317.54 13.49
3.09 3.40 202.34 312.58 13.26
3.55 3.60 209.71 305.95 13.03
4.01 3.80 219.05 302.75 12.94
4.47 4.00 234.13 307.42 12.85
4.93 4.20 247.66 309.70 12.76
5.38 4.40 258.73 308.84 12.83
5.83 4.60 271.59 310.09 12.83
6.29 4.80 285.11 311.96 12.71
6.74 5.00 296.99 311.97 12.63
7.20 5.20 305.43 308.50 12.54
7.67 5.40 313.10 304.53 12.34
8.15 5.60 317.03 297.34 12.10
8.64 5.80 317.79 287.76 11.73
9.14 6.00 326.02 285.38 11.37
9.65 6.20 332.04 281.27 11.34
10.17 6.40 339.61 278.70 11.23
10.69 6.60 344.62 274.25 11.26
11.24 6.80 342.65 264.66 11.27
11.80 7.00 334.50 251.00 11.10

Numbers from best stock dyno run:

RunFile_003.drf: 97.44 °F 29.76 in-Hg Humidity: 27 % STD: 1.04 Average Gear Ratio: 52.91

s RPM x1000 hp ft-lbs Air/Fuel
0.78 2.00 114.01 299.34 14.77
1.23 2.20 130.40 311.30 12.55
1.66 2.40 144.64 316.53 12.32
2.10 2.60 156.67 316.49 12.67
2.54 2.80 166.55 312.41 12.72
2.97 3.00 181.77 318.22 12.68
3.41 3.20 195.84 321.42 12.77
3.83 3.40 209.16 323.09 12.77
4.26 3.60 221.00 322.43 12.75
4.70 3.80 232.66 321.57 12.75
5.13 4.00 244.33 320.81 12.66
5.56 4.20 256.54 320.80 12.65
6.00 4.40 269.63 321.85 12.77
6.43 4.60 282.73 322.82 12.77
6.87 4.80 292.96 320.56 12.74
7.31 5.00 300.86 316.04 12.78
7.76 5.20 308.36 311.45 12.57
8.23 5.40 310.43 301.93 12.07
8.71 5.60 314.03 294.52 11.75
9.20 5.80 313.20 283.62 11.33
9.71 6.00 320.47 280.52 11.09
10.22 6.20 326.65 276.71 11.15
10.75 6.40 328.55 269.62 11.05
11.29 6.60 333.93 265.73 11.22
11.89 6.80 322.21 248.88 10.89
12.50 7.00 312.72 234.58 10.30



I do love the exhaust though

 

[Rody]

Very strange... you should at lease gain on torque with the headers... Any idea how the MAFS are doing?

 

[M5Gator]

Very strange... you should at lease gain on torque with the headers... Any idea how the MAFS are doing?

i thought so too...at least regarding the loss in hp/tq in mid range (10-15 ft-lb in some areas!)

i've been meaning to test the MAFs, never have and figure they could use a cleaning at a minimum. would this possibly be the cause? would the MAFs have changed that much in one month? had the stock dyno done in late may and headers dyno done yesterday.

 

[M5 London]

Yikes !!

Were there any codes including any soft codes on your post dyno run ??

Good Luck !

 

[graffix000]

By your request for tuner recommendations, I am assuming you do not have a tune for the headers? That will help out a bit, but I am surprised by the numbers too. Good luck!

 

[Rody]

I thought that was the nice thing about supersprint, all sensors can be placed back so no remap is needed.

 

[M5 London]

I thought that was the nice thing about supersprint, all sensors can be placed back so no remap is needed.

What do you mean mate ?

 

[Rody]

With other headers you sometimes lose the o2 or labda sensors so you must use a custom map, i thought. I was told the nice thing about supersprint was that it's just bolt on and go.

 

[M5 London]

With other headers you sometimes lose the o2 or labda sensors so you must use a custom map, i thought. I was told the nice thing about supersprint was that it's just bolt on and go.

For a start headers on our cars do not have o2 sensors (AKA Lambda Sensors), on them. All 4 of our o2 sensors are acutally on the cats.

Headers can be swapped out in theory, by not even unscrewing the o2 sensors.

I run my car with aftermarket performance headers, NOT SS, with a totally stock MAP too and my o2 sensors have not been lost

Cheers

 

[ECB]

I'm far from a dyno expert but your A/F seem off. I had good success with a Powerchip tune. With Dinan CAI, SS headers/cats, and PC tune, my car made 380whp.

 

[Mike S.]

Is it possible that the high ambient temps are causing the ECU to dump fuel and pull timing to help with engine temps? You seem to be really rich at points (as you noted) on both stock and header runs.

I know when a board member here in the DFW area installed a supercharger and did a dyno, he was disappointed in the results, but it was really hot at the time.

Just a thought...

 

[M5Gator]

By your request for tuner recommendations, I am assuming you do not have a tune for the headers? That will help out a bit, but I am surprised by the numbers too. Good luck!

That is correct. As seen in sig, my current tune is just the Dinan stage 1 which is not for headers. I'm still confused by the drop from stock numbers in mid range though.

I thought that was the nice thing about supersprint, all sensors can be placed back so no remap is needed.

I still have stock cats, but a remap is still usually needed to accomodate the increased airflow.

Yikes !!

Were there any codes including any soft codes on your post dyno run ??

Good Luck !

I didn't check codes the day of (but I will today). I checked them last week and the only code showing was the P0441 EVAP Emission something or other. Basically the code that goes off when the Fuel Tank Breather Valve is not functioning, but not supposed to affect power from what I've read. SES light is on for that.

I'm far from a dyno expert but your A/F seem off. I had good success with a Powerchip tune. With Dinan CAI, SS headers/cats, and PC tune, my car made 380whp.

Yes, my AF is definitely off and very rich above 5k rpm.

Is it possible that the high ambient temps are causing the ECU to dump fuel and pull timing to help with engine temps? You seem to be really rich at points (as you noted) on both stock and header runs.

I'm not so much disappointed in the number (345 whp) but moreso that it is only a 10whp increase over my stock numbers and some significant drops in the mid range from stock. Same dyno and fan, same operator, same 93 octane gas, same hot weather conditions (98 deg). I know if was using 100 octane and had 3 massive fans blasting into the front instead of just the one from stock, the jump should be higher but I am trying to keep as much the same as possible.

I was planning on getting a tune anyhow but wanted to see how the headers/x-pipe would affect numbers without anything else. I guess not as good as I would have thought!

I'm going to pull codes during lunch in a bit and maybe that will give some insight. Will be heading to Europe (Belgium, London, Amsterdam :biggrinbounce for 2 weeks but will test MAFs and clean them when I return.

I appreciate the input so far..sounds like I should expect quite a bit more power, which should be attainable if no codes, clean/good MAFs and proper tune to correct the A/F ratio.

Any other thoughts please do chime in!

 

[mooch]

I'm not sure a "header" tune is going to make that much of a difference. It's my understanding that most header tunes are to compensate for the lean condition caused by increased flow through the headers. It looks like you are plenty rich... perhaps you have a flow restriction on the intake side which is preventing the headers from making the difference you are expecting and resulting in the rich condition you are seeing here.

Or, as Mike S. notes above, perhaps this is all due to the DME r-e-t-a-r-ding the timing and enriching the mixture to compensate for high temps.

 

[M5Gator]

I'm not sure a "header" tune is going to make that much of a difference. It's my understanding that most header tunes are to compensate for the lean condition caused by increased flow through the headers. It looks like you are plenty rich... perhaps you have a flow restriction on the intake side which is preventing the headers from making the difference you are expecting and resulting in the rich condition you are seeing here.

Or, as Mike S. notes above, perhaps this is all due to the DME r-e-t-a-r-ding the timing and enriching the mixture to compensate for high temps.

I thought the headers would make it run a bit more lean as well and thought I might even get lucky and the headers would help correct the rich AF ratios seen from stock. I guess not that lucky. Maybe I'll put off packing for my trip another day or two and test the MAFs before I leave. It's gonna bother me the whole time otherwise lol..

Yikes !!

Were there any codes including any soft codes on your post dyno run ??

Pulled the codes and only P0441 came up as shown in pictures. Cleared the code again, but I know its one of those that will just come back until I get the breather valve replaced.

Aside from testing MAFs are there other things I can check into that might be causing it to run this rich and/or lose power and torque from stock?

 

[MrCrashRR]

Your A/f ratios are horrible. Reset the adaptation and get a tune ASAP.

 

[M5 London]

I have a simple rule :

Codes = NO Dyno

NO Codes = Dyno

Cheers

 

[Mike S.]

I really think the heat has something to do with it. Our cars don't like it and while they'll run pretty good in really hot weather, they just don't put out the power. I notice it in the summer months here in Texas and when I get a chance to drive in marginally cooler weather, like yesterday when it was a full 20 degrees F cooler outside, you could feel the difference.

Kumaran is right, though. No dyno till all codes are fixed. That's a good rule of thumb.

 

[M5Gator]

Your A/f ratios are horrible. Reset the adaptation and get a tune ASAP.

Yep, real bad A/F ratios I know. How do I reset adaptation? And what tune should I get for headers?

I have a simple rule :

Codes = NO Dyno

NO Codes = Dyno

Cheers

Agreed, but I wanted to get a dyno before I left the country and figured the beather valve wouldn't affect power. I'm getting it fixed when I return though and will try a few other things as well. Thanks to all who've given suggestions and PM'ed me, much appreciated.

 

[Brecus.com]

And what tune should I get for headers?

PM Sent! :typing:

 

[vantaam5]

Before going for a tune,I would start trouble shooting first.

It is obvious that something is going wrong there....

Do not have the time now to look into it further right now,but will do this tonight!