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John
I would assume its the AMS injectors causing problems since I highly doubt its the turbos.
I agree. Wouldn’t be the first time tuners have had issues with the AMS Injectors. Although, this would be a first - AMS themselves having some tuning issues with the AMS Injectors (note and forewarning: they won’t ever blame it on their products or tuning though).

@JohnInNH - Looking forward to your honest review, journey, and results.
 

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Dang John sometimes I can't help but admire your patience with this build, understandably you are one of the first adopters so tweaks/calibrations
are expected but it's not something I could put up with myself. lol
 
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2018 Q50 AWD Red Sport
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Discussion Starter #243
In all reality I just think the tuning doesn't have the required # of revisions to address it yet.

It's very early to think anything is "wrong" yet.

Go auto spent 99.9% of the time using 100 octane fuel when I wish they spent all that dyno time with 93.

The 100 map was incredible. So now we are building the 93 map. I have confidence it will get sorted out. It's a lot better than it was and a good part of the RPM and torque demand areas pull like crazy.

I had to wait until the roads dried off b4 logging hits, otherwise I'd spin like crazy.

I can tell the potential is there. I'm at the 3rd or 4th revision I believe w/o checking to be sure. Way to early to bitc$.

I was at 13 or 14 revisions with Sebastian b4 the new turbos.
 
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Maybe the Level 10 built trans is making it hard to tune as well?
 

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Discussion Starter #245
My replacement non-resonated X-pipe arrived this afternoon. It goes in Tuesday PM. I expect it will have some effect on the tuning so I will do more logging AFTER I get it put in, and send them to AMS to look at.

The latest map resolved the idle and starting issues. Now to dial in the WOT performance.

Hopefully it's not to loud and doesn't drone on the highway.

More later.
 

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My replacement non-resonated X-pipe arrived this afternoon. It goes in Tuesday PM. I expect it will have some effect on the tuning so I will do more logging AFTER I get it put in, and send them to AMS to look at.

The latest map resolved the idle and starting issues. Now to dial in the WOT performance.

Hopefully it's not to loud and doesn't drone on the highway.

More later.
Why non resonated this time?
 

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Discussion Starter #247
Why non resonated this time?
I can get the resonated X-pipe TIG welded and that way I'll have one of each.

I also have a gut feel there is something going on internally, in the side where both the front and rear welds failed.

During last winter I would remote start the car, with the garage door closed, and let it run for a couple of minutes. The carbon "spot" was 2x the diameter on one side showing much more flow on one side.

I have no clue what the design looks like inside, so I'm purely speculating that something in there, may be causing a flow differential. 🤔 If something IS wrong inside, it would explain why I have made less power than other people, with the same set up as mine.

So a non-resonated X-pipe made sense to me.

I will try to measure the flow difference between the two sides. It may be to small of a difference to notice by hand (very crude), but worth a try.

If the non-resonated X-pipe is to loud I'll just TIG up the failed welds on the resonated X-pipe and put it back on.

AMS may be able to get more performance from the non-resonated X-pipe.
 

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I can get the resonated X-pipe TIG welded and that way I'll have one of each.

I also have a gut feel there is something going on internally, in the side where both the front and rear welds failed.

During last winter I would remote start the car, with the garage door closed, and let it run for a couple of minutes. The carbon "spot" was 2x the diameter on one side showing much more flow on one side.

I have no clue what the design looks like inside, so I'm purely speculating that something in there, may be causing a flow differential. 🤔 If something IS wrong inside, it would explain why I have made less power than other people, with the same set up as mine.

So a non-resonated X-pipe made sense to me.

I will try to measure the flow difference between the two sides. It may be to small of a difference to notice by hand (very crude), but worth a try.

If the non-resonated X-pipe is to loud I'll just TIG up the failed welds on the resonated X-pipe and put it back on.

AMS may be able to get more performance from the non-resonated X-pipe.
Not sure I'd worry too much about unequal flow through the system its simply following the path of least resistance, probably isn't
strange for flow to favor one side or another.

Be It could be from turbulence or slight warping somewhere in the system be it from the factory or the welds that were done after
the fact. But that's just my $0.02 cents on the matters.
 

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The resonators should be straight thru flow. I have not seen any other kind.

For the X part of the pipe they showed a video on their Youtube channel or IG Channel that just showed the merge point as open between the sides. Not anything like a DR Gas X pipe. Very simple design but obviously effective.
 

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if the resonators are straight through as most are, you wouldnt need a retune or any adjustment to your tune.
 

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My replacement non-resonated X-pipe arrived this afternoon. It goes in Tuesday PM. I expect it will have some effect on the tuning so I will do more logging AFTER I get it put in, and send them to AMS to look at.

The latest map resolved the idle and starting issues. Now to dial in the WOT performance.

Hopefully it's not to loud and doesn't drone on the highway.

More later.
It shouldn't be too loud since you have the 14" touring mufflers if I remeber correctly. There may be some drone above 78mph when you are sitting at 2k rpm when trying to keep speed or accelerate.
 

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Discussion Starter #254
I sent AMS my last resonated X-pipe logs. 7 logs. I am still getting soot on my back bumper so someplace it's to rich. I'm sure we will get it worked out in a few new tweaked revisions of the map.

I told Jacob those 7 logs will be the last before I get the new X-pipe installed. I'll probably get a new map from him before it goes up on the lift.

The 7 logs have a good mix of driving with the exception of 5500+ RPM.

After the new pipe is in I can get better logs. Time is running out before the snow hits. Winter is knocking on the door. I've already had two hard frosts. Still no ice on the pond which is still very low. The last rain only gave me 3" of water. I'm down about 20" from full. The most severe drought since I have lived here.

I'm looking forward to getting the map dialed in. Hopefully before I put my snow tires on. 😳 I don't feel good about going 100+ MPH with them on.

I'll post how the non-resonated X-pipe sounds after it's on.... more later.
 

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I thought I recall hearing you say that AMS was thinking that one of your converters may be faulty so this could be causing flow issues on one side. I was also thinking you had AMS full downpipes. Did this get resolved? Im still not sold in the X pipe causing such a huge issue...
 

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Discussion Starter #256
The design is straight through. And again I am saying it's improbable it's the X-Pipe. But something caused both welds to fail on one side.

TIG welding it will give me one of each. If there is no change I'll just have a different sounding exhaust.

But on the slim chance it helps it's a win. I may even like the change in sound. Time will tell.
 

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Discussion Starter #257
Non-resonated X-pipe is in and I have a few miles on it now (data logging).

I prefer it, and it's quieter in Sport mode except "on throttle" at certain RPM's.

It's both quieter and louder. With the resonated X-pipe Sport mode was pretty loud and droned at highway speeds cruising. Now it's pretty quiet unless I put my foot into it.

So I now find Sport and Sport + an option I will use more. No longer droning on the highway just cruising along. The resonated X-pipe got old FAST due to the drone in Sport mode on the highway.

Yes, it is pretty loud at times. At 2 different RPM's and TPS's it rasps. So when I'm on it hard in automatic shift mode it's mellow throaty till it hits the magic spots and rasps briefly till the RPM changes.

Low throttle in Standard mode is a tad louder but not enough to even notice, unless the windows are down.

Bottom line I prefer it to the resonated X-pipe and now use Sport+ more often.

I did notice AFR differences till the ECU corrected it. From off throttle to back on throttle the AFR would hit 11.* vs 12.* for a second. That's the time my AFR is the lowest (very briefly). (Sorta like an accelerator pump would act in a carburetor)

More as I get some decent miles on it.
 

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Nice glad you are enjoying the resonated setup, I love me an aftermarket exhaust but highway drone at my cruising RPMs can be pretty dang tedious.
 

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Nice glad you are enjoying the resonated setup, I love me an aftermarket exhaust but highway drone at my cruising RPMs can be pretty dang tedious.
John went to a non-resonated X-pipe.
 

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