GT PRO Double X-Pipe Installed
#26
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Super...what is your speculation on what deleting the primaries will gain? I know people are gettin 40-50whp with LTs...
My concern would be noise like Brian said. Since I don't track (at least not until I leave this God-foresaken island), I'm not sure the extra HPs (and associated noise) are going to get me much other than tickets.
And Brian, I agree, the sound is just beautiful with both x pipes...I almost want to hear what the X vs. XX difference is, as I've fallen in love with the new sound, and am curious what difference the resonator removal makes. It is amazing how tied up the exhaust is stock (even though I think the stock C63 exhaust is one of the best I've heard).
My concern would be noise like Brian said. Since I don't track (at least not until I leave this God-foresaken island), I'm not sure the extra HPs (and associated noise) are going to get me much other than tickets.
And Brian, I agree, the sound is just beautiful with both x pipes...I almost want to hear what the X vs. XX difference is, as I've fallen in love with the new sound, and am curious what difference the resonator removal makes. It is amazing how tied up the exhaust is stock (even though I think the stock C63 exhaust is one of the best I've heard).
#27
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Super...what is your speculation on what deleting the primaries will gain? I know people are gettin 40-50whp with LTs...
My concern would be noise like Brian said. Since I don't track (at least not until I leave this God-foresaken island), I'm not sure the extra HPs (and associated noise) are going to get me much other than tickets.
My concern would be noise like Brian said. Since I don't track (at least not until I leave this God-foresaken island), I'm not sure the extra HPs (and associated noise) are going to get me much other than tickets.
The beauty of this mod is it would be hot-swappable. Two bolts per manifold, one bolt on each down pipe and unscrew/screw in the O2s and you are stock or catless. To me, this is perfect for a track only application.
Brian, need me to send a deposit?
![naughty](https://mbworld.org/forums/images/smilies/naughty.gif)
#28
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C63 AMG
Not 40-50. I've got a head-start with my PLM manifolds with their larger collector outlets. A nice 2.5" catless downpipe will make power over the stock downpipe with it's shrunken inlet tube and restrictive primary cat. It's just a question of how much and where in the powerband.
The beauty of this mod is it would be hot-swappable. Two bolts per manifold, one bolt on each down pipe and unscrew/screw in the O2s and you are stock or catless. To me, this is perfect for a track only application.
Brian, need me to send a deposit?![naughty](https://mbworld.org/forums/images/smilies/naughty.gif)
The beauty of this mod is it would be hot-swappable. Two bolts per manifold, one bolt on each down pipe and unscrew/screw in the O2s and you are stock or catless. To me, this is perfect for a track only application.
Brian, need me to send a deposit?
![naughty](https://mbworld.org/forums/images/smilies/naughty.gif)
#29
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I'll get re-tuned to prevent CELs, but that's likely it for the first test. If the data comes back unfavorable, I'll figure something out . . . but I'm pretty confident all will be good.
![Stick Out Tongue](https://mbworld.org/forums/images/smilies/tongue.gif)
BTW, my A/F @ 6000 RPM:
w/ Kleemann K1 - 12.38
+ PLM Manifolds - 12.42
+ GT PRO X-Pipe - 12.47
Last edited by superlubricity; 04-08-2010 at 02:31 AM. Reason: added A/Fs
#31
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so the XX takes the place of the sec. cat and the resonator?
the single x takes the place of only the sec. cat?
your LTs removes the prim. cat and the sec cats?
i guess i'm trying to figure out from an upgrade point. the XX sounds like something i might be interested in, but if i decide to go LT in the future, what parts would i end up with... and could it be sold for someone else to use?
will the double xx require a new tune? or is it mainly sound and not much gain?
#34
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neither one of the pipes (single X or XX) require a tune.....also, power gains should be similar to what has been previously seen in the single X because as far as i know, removing the resonator does not free up any more power.
However, i dont think anybody has before/after dyno'd a XX...unless Brian has
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#35
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C63 AMG Arctic w/ Stage 1 Tune, DoubleXX pipe, MCD-631X coming soon
Yes, just at unbreakable1 just stated, he is 100% correct (thank you for helping me out here)
MikeG C63 AMG and bluejae: The Single X or the Double XX are engineered to be used with or without a tune, and will pick up power both ways as we've shown on the dyno. The Double XX does really make the car sound "right". LT's will not be able to use the Single X (front pre cat delete) however you can retain the Single X R1 (resonator delete), So..if you go LT's in the future, you will have a Single X to sell.
Regarding power on the "SingleX" and "DoubleXX" I have not seen much if any difference power wise adding the SingleX R-1 (resonator delete), so I tell guys that the R1 is to tune sound, not power, however I will tell you this somewhat depends on the tune as well, because on my car, the torque curve is much broader vs the "other cars" I've tested with "other tunes" when I added the SingleX R1 to my set up.
Super...LOL yeah yeah I'm working on it brother, trust me, you are my first call.
MikeG C63 AMG and bluejae: The Single X or the Double XX are engineered to be used with or without a tune, and will pick up power both ways as we've shown on the dyno. The Double XX does really make the car sound "right". LT's will not be able to use the Single X (front pre cat delete) however you can retain the Single X R1 (resonator delete), So..if you go LT's in the future, you will have a Single X to sell.
Regarding power on the "SingleX" and "DoubleXX" I have not seen much if any difference power wise adding the SingleX R-1 (resonator delete), so I tell guys that the R1 is to tune sound, not power, however I will tell you this somewhat depends on the tune as well, because on my car, the torque curve is much broader vs the "other cars" I've tested with "other tunes" when I added the SingleX R1 to my set up.
Super...LOL yeah yeah I'm working on it brother, trust me, you are my first call.
Last edited by Brian GT PRO; 04-08-2010 at 11:12 PM.
#37
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i should be ablt to dyno next week, showing K1 vs K1 + XX. i'm hoping for 10-12whp peak gain and 15-20whp mid-range. it definitely picked up mid-range...it smokes now between 30-50mph in 2d gear where after K1 smoked only 45-55whp in 2d gear. as soon as i can get back to dyno shop, you'll know the gains.
#38
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Miami, when you go back to the dyno, bring a USB/Flash drive and ask for all of your runfiles. When you get home, you can load them in to WinPEP (Free download from dynojet.com) and play around with the data and even make custom graphs. It's pretty cool stuff.
#39
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I downloaded winpep and have used it a few times...it is pretty cool...between that and Vbox, I'm having a blast.
I'm going to try and run down tomorrow. Its my anniversary though, so not sure how that will go
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I'm VERY curious on the power gains, because I can definitely feel it strong in the 1st/2d gear range from about 20-50...it is really pulling much harder...I just hope the results support that (and its not the sound deceiving me).
#40
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Results are back from dyno and NOT very good.
I went from 408whp/376.7wftlb to 395whp/363wftbl.
Run File 005 was post Kleemann K1 tune
Run File 001 was post Double XX with K1 tune (5th gear)
Run File 006 was post Double XX with K1 tune (4th gear)
if you look, the car was running really rich...my 5th gear run was even lower (384whp/356wftlb).
looks like i need a retune to get my a/f squared away...but for now, in higher gears, the Double X is costing me power
I went from 408whp/376.7wftlb to 395whp/363wftbl.
Run File 005 was post Kleemann K1 tune
Run File 001 was post Double XX with K1 tune (5th gear)
Run File 006 was post Double XX with K1 tune (4th gear)
if you look, the car was running really rich...my 5th gear run was even lower (384whp/356wftlb).
looks like i need a retune to get my a/f squared away...but for now, in higher gears, the Double X is costing me power
![Confused](https://mbworld.org/forums/images/smilies/confused.gif)
Last edited by miami1lt; 04-10-2010 at 11:10 PM.
#41
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by the way, i still back my claim that it smokes in 2nd gear from 30-50...makes sense, because the a/f is only bad in higher gears where back pressure is gone. I still think in 2nd-3rd gears, I may have picked up some horses...esp at lower RPMs...it is the higher gears and top end where I lost some...
Does anybody know a tuner out there that can correct this on my ECU?
Does anybody know a tuner out there that can correct this on my ECU?
#42
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Results are back from dyno and NOT very good.
I went from 408whp/376.7wftlb to 395whp/363wftbl.
Run File 005 was post Kleemann K1 tune
Run File 001 was post Double XX with K1 tune (5th gear)
Run File 006 was post Double XX with K1 tune (4th gear)
if you look, the car was running really rich...my 5th gear run was even lower (384whp/356wftlb).
looks like i need a retune to get my a/f squared away...but for now, in higher gears, the Double X is costing me power![Confused](https://mbworld.org/forums/images/smilies/confused.gif)
I went from 408whp/376.7wftlb to 395whp/363wftbl.
Run File 005 was post Kleemann K1 tune
Run File 001 was post Double XX with K1 tune (5th gear)
Run File 006 was post Double XX with K1 tune (4th gear)
if you look, the car was running really rich...my 5th gear run was even lower (384whp/356wftlb).
looks like i need a retune to get my a/f squared away...but for now, in higher gears, the Double X is costing me power
![Confused](https://mbworld.org/forums/images/smilies/confused.gif)
How many dyno pulls did you do today? How much cool-down time did you allow between runs? I've found it takes a couple test pulls before getting anything accurate or consistent. We usually throw the first two pulls out the window because they are always very low. By the 3rd, 4th and 5th pull things start to show peak HP consistently.
Any chance you can send me the runfiles?
BTW, on one run your A/F actually looks lean in the middle, on another run it just flat-lines . . . almost like the operator didn't get a good reading from your car. No reason for the X pipe to cause that.
#43
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Odd results indeed. Did anything else change on the car?
How many dyno pulls did you do today? How much cool-down time did you allow between runs? I've found it takes a couple test pulls before getting anything accurate or consistent. We usually throw the first two pulls out the window because they are always very low. By the 3rd, 4th and 5th pull things start to show peak HP consistently.
Any chance you can send me the runfiles?
BTW, on one run your A/F actually looks lean in the middle, on another run it just flat-lines . . . almost like the operator didn't get a good reading from your car. No reason for the X pipe to cause that.
How many dyno pulls did you do today? How much cool-down time did you allow between runs? I've found it takes a couple test pulls before getting anything accurate or consistent. We usually throw the first two pulls out the window because they are always very low. By the 3rd, 4th and 5th pull things start to show peak HP consistently.
Any chance you can send me the runfiles?
BTW, on one run your A/F actually looks lean in the middle, on another run it just flat-lines . . . almost like the operator didn't get a good reading from your car. No reason for the X pipe to cause that.
We did 3 pulls...the first one was 384whp, then 376whp, then 395whp...remember, my K1 was 408whp.
As for runfiles, I will hopefully get them emailed to me tomorrow...didn't have a thumbdrive today, but I will gladly let you scrutinize.
Also, yes, it was lean a bit, but the operator told me it looked like the ECU was dumping gas...if you look at the flat line that is near 15, that is the K1 only...the two where it dives towards 12 was today. The one where it dives soonest is the 384whp 5th gear run...where it takes a little longer to dive is the 4th gear run at 395whp...the dive in A/F ratio definitely corresponded well with the loss in power. I was tempted to ask him to do another 5th gear run, but it was obvious that my A/F was suffering.
I noticed the other day doing 60-100 runs that my times weren't any better than before...it is strange, because I've posted some of my best (and easiest) 0-60 times (been down around 4.5 when averaging 4.8-4.9 before), but my 60-100 times aren't any better, and may be worse...that is consistent with losing higher end power, but gaining low-mid end power in the shorter gears.
I'm dazed right now, because i LOVE the doubleX, but am VERY surprised to be losing power...can't wait for you to have a look at the run files!
Of note, it was 13F hotter in there today...nearly 95F...with the two fans running, it still could have used some more cool down time. There is a chance with a few more runs and cooler conditions I'd be CLOSE to the K1 only run...but that still shouldn't be the case...there were no gains ANYWHERE along the curve...that to me is shocking!
Last edited by miami1lt; 04-11-2010 at 03:11 AM.
#45
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^^^i'll send it off no problem...but does anybody reflash for x-pipes? most reflashes are for o2 sensor deletes, which i don't need...i need something that makes the ecu realize it has new exhaust....any thoughts?
#46
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I'm anxious to see if that A/F can get straigtened out, and the temp could be a factor...but I'm not surprised that a nice full Double X may cost a few horsepower. Has anyone ever seen this on ANY other stock or tuned car?
Has anyone established how restrictive the resonator is? I thought it was fairing free-flowing.
Also, I'm anxiously waiting for the primary cat delete and single X secondary cat delete!!!!
Has anyone established how restrictive the resonator is? I thought it was fairing free-flowing.
Also, I'm anxiously waiting for the primary cat delete and single X secondary cat delete!!!!
#47
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Inline.
First, no other changes, just the two x pipes since the K1 install.
We did 3 pulls...the first one was 384whp, then 376whp, then 395whp...remember, my K1 was 408whp.
That 3rd pull looks like it was starting to pick up. There is a chance that with a couple more runs would have had you back over 400. These cars are finicky the first couple/few runs.
I know it doesn't help now, but my rule is don't stop making runs until the numbers 1) get consistent and 2) then start to drop off.
As for runfiles, I will hopefully get them emailed to me tomorrow...didn't have a thumbdrive today, but I will gladly let you scrutinize.
No problem. I love looking at the data. I don't think I'll find much given there were only 3-runs made.
Also, yes, it was lean a bit, but the operator told me it looked like the ECU was dumping gas...if you look at the flat line that is near 15, that is the K1 only...the two where it dives towards 12 was today. The one where it dives soonest is the 384whp 5th gear run...where it takes a little longer to dive is the 4th gear run at 395whp...the dive in A/F ratio definitely corresponded well with the loss in power. I was tempted to ask him to do another 5th gear run, but it was obvious that my A/F was suffering.
Good to know the run with the A/F of ~15 was before the X-Pipe. No reason for A/F to read flat-line super-lean like that. Blame the operator for that. In fact, I bet he just forgot to plug it in
.
It's still odd that the two other runs are very different between 3.5K and 5.5K.
I noticed the other day doing 60-100 runs that my times weren't any better than before...it is strange, because I've posted some of my best (and easiest) 0-60 times (been down around 4.5 when averaging 4.8-4.9 before), but my 60-100 times aren't any better, and may be worse...that is consistent with losing higher end power, but gaining low-mid end power in the shorter gears.
I'm dazed right now, because i LOVE the doubleX, but am VERY surprised to be losing power...can't wait for you to have a look at the run files!
Of note, it was 13F hotter in there today...nearly 95F...with the two fans running, it still could have used some more cool down time. There is a chance with a few more runs and cooler conditions I'd be CLOSE to the K1 only run...but that still shouldn't be the case...there were no gains ANYWHERE along the curve...that to me is shocking!
The extra heat could certainly be part of the problem. Conditions were definitely worse but the CF was adjusted to .98 versus .97 previously. I'm curious as to what the uncorrected #'s look like.
We did 3 pulls...the first one was 384whp, then 376whp, then 395whp...remember, my K1 was 408whp.
That 3rd pull looks like it was starting to pick up. There is a chance that with a couple more runs would have had you back over 400. These cars are finicky the first couple/few runs.
I know it doesn't help now, but my rule is don't stop making runs until the numbers 1) get consistent and 2) then start to drop off.
As for runfiles, I will hopefully get them emailed to me tomorrow...didn't have a thumbdrive today, but I will gladly let you scrutinize.
No problem. I love looking at the data. I don't think I'll find much given there were only 3-runs made.
Also, yes, it was lean a bit, but the operator told me it looked like the ECU was dumping gas...if you look at the flat line that is near 15, that is the K1 only...the two where it dives towards 12 was today. The one where it dives soonest is the 384whp 5th gear run...where it takes a little longer to dive is the 4th gear run at 395whp...the dive in A/F ratio definitely corresponded well with the loss in power. I was tempted to ask him to do another 5th gear run, but it was obvious that my A/F was suffering.
Good to know the run with the A/F of ~15 was before the X-Pipe. No reason for A/F to read flat-line super-lean like that. Blame the operator for that. In fact, I bet he just forgot to plug it in
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
It's still odd that the two other runs are very different between 3.5K and 5.5K.
I noticed the other day doing 60-100 runs that my times weren't any better than before...it is strange, because I've posted some of my best (and easiest) 0-60 times (been down around 4.5 when averaging 4.8-4.9 before), but my 60-100 times aren't any better, and may be worse...that is consistent with losing higher end power, but gaining low-mid end power in the shorter gears.
I'm dazed right now, because i LOVE the doubleX, but am VERY surprised to be losing power...can't wait for you to have a look at the run files!
Of note, it was 13F hotter in there today...nearly 95F...with the two fans running, it still could have used some more cool down time. There is a chance with a few more runs and cooler conditions I'd be CLOSE to the K1 only run...but that still shouldn't be the case...there were no gains ANYWHERE along the curve...that to me is shocking!
The extra heat could certainly be part of the problem. Conditions were definitely worse but the CF was adjusted to .98 versus .97 previously. I'm curious as to what the uncorrected #'s look like.
#48
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Are there other dynojets you could try?
If after going back to the dyno without getting better results, maybe try reinstalling the resonator? ..just a thought. It just still seems strange that you'd need another x pipe after you already have one closer to the motor that can properly scavenge. Maybe try some straight pipes instead?
#49
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You don't need a reflash for an X-pipe. The increased air flow is not significant enough to warrant adding fuel...and I wouldn't want any tune that would make my car leaner so that I can make a tiny bit more rwhp. Keep in mind that when you run on the streets, there is more air flow and your AFRs would be leaner than what was shown on the dyno. I'd rather be safe than sorry when it comes to AFRs. Yours are pretty safe, other than that one semi-lean run that superlubricity alluded to. I wouldn't go leaner to gain more power if I were you. You were aiming quite optimistically high with this mod, hoping that it would yield 10-12whp peak gain and 15-20whp mid-range...nothing wrong with that, it was just unrealistic. There's nothing wrong with that, it's just you'll be more disappointed in the end.
#50
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You don't need a reflash for an X-pipe. The increased air flow is not significant enough to warrant adding fuel...and I wouldn't want any tune that would make my car leaner so that I can make a tiny bit more rwhp. Keep in mind that when you run on the streets, there is more air flow and your AFRs would be leaner than what was shown on the dyno. I'd rather be safe than sorry when it comes to AFRs. Yours are pretty safe, other than that one semi-lean run that superlubricity alluded to. I wouldn't go leaner to gain more power if I were you. You were aiming quite optimistically high with this mod, hoping that it would yield 10-12whp peak gain and 15-20whp mid-range...nothing wrong with that, it was just unrealistic. There's nothing wrong with that, it's just you'll be more disappointed in the end.
It is the only dyno jet on the island, so I am kinda stuck with them...all the rest are dyno paks.
Would adding headers or opening up the filters/intakes do anything to help the air flow w/o a reflash?
I still feel that what i may lose in the top of 4th/5th gear I may pickup in the mid of 2d/3rd...and, I still LOVE the sound...just can't believe the pipes screw with the a/f that much!!!