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Discussion Starter #1
So I've seen everybody here say people need a tune for lower DPs (AMS). Makes sense and I'm absolutely going to.

However, a couple things make me not want to right away.

1. The tuner is going to charge 200 to install (something I can do myself and have fun doing it).
2. The only issue is the CEL from the CAT not sensing correctly? I've also read that some people aren't getting any CELs at all.
3. Spread cost out.
4. I can get a little boost in noise and power while I wait to get the tune.

The only reason that would prevent me would be engine damage or make the car drive poorly.
Even if this is the case, could I install and make a single trip to the tuner?

Only reason I haven't done a lower DP and tune already is I just bought a ring for my GF.

I have a 2016 RS400 AWD.

Thanks!
 

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Seems you have a plan. I can't answer your question, but sure the manufacturer can. This is why I got the FI GESI down pipes so I can run w/o a tune. They are pricey. ugg.. I plan on a tune later.
 

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AMS Lower Down Pipes should not need a tune. It says several times on the page that they will not throw a CEL.
Now to get the most out of them you should tune, but they should absolutely work on a stock car, no tune, no CEL.


I have a set being installed Monday along with the AMS Heat Exchanger. No other mods and I'm not planning on tuning right away.
 

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Discussion Starter #4
I have a set being installed Monday along with the AMS Heat Exchanger. No other mods and I'm not planning on tuning right away.
You would be THE MAN if you could let me know how it goes!! :D Seriously though, I'd be super grateful.

AMS Says:
"During testing our shop Q60 with our Red Alpha Downpipes, and Red Alpha Tune, our Engine Calibrators saw gains across the power band in both wheel horsepower and torque and all without a CEL!"

KEY phrase: "and Red Alpha Tune".

That's what made me question. But you'll find out!
 

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I just called AMS.


The Lower Downpipes should not through a CEL on a stock car. So there you go. I believe the reason is that the second set of catalytic converters that are removed with these downpipes are not monitored by the ECU.
 

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Discussion Starter #6
Awesome! I'm honestly really interested in your results. That would confirm my upgrade path!
 

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I just called AMS.

The Lower Downpipes should not through a CEL on a stock car. So there you go. I believe the reason is that the second set of catalytic converters that are removed with these downpipes are not monitored by the ECU.
My '17 Q60 Red Sport w/FI LDPs & Cat-back has been operating for over a year w/o a tune and no CEL (ever). I added the BT JB1 and then upgraded to the BT JB4 shortly there-after and still did not generate a CEL. I eventually will get an EcuTek tune.

Technically, the 2nd Cats are for cold-start emissions only. Once the Primary Cat is warmed-up, and the ECU goes into "Closed-Loop", with the primary O2 sensor active, the 2nd O2 sensor is there only to monitor the Primary Converter efficiency. You must have either the stock Primary converter or the FI Full Downpipes installed w/GESI Cat ($$$) to prevent the ECU from setting a flag (CEL) for failure to achieve "Readiness", in OBD-II speak.
 

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I added the AMS lowers to my FI cat back 2 weeks ago and have not had any issues. I also have the Burger Stage 1 and don't plan on tuning any time soon. Removing the secondary cats really opens things up. Waiting for the release of the AMS intakes for my next mod so I can better hear those turbos spinning.
 
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Discussion Starter #9
Great to hear!

What should I expect with just the AMS lower DPs installed on my RS400? Throttle response? Nicer engine sound?

Thanks!
 

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I got downpipes, y pipe and top speed pro exhaust... no CEL light.. i had the CEL when i added the spacers. I removed all of them, reset the code then it never came back on. So with the DP you’ll be fine With or without the tune. I use the JB4 so my car has been doing fine. I recommend NOT having all 4 cats as even Visconti Tubing suggested not to remove them due to turbo spikes or whatever it was called
 

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I added the AMS lowers to my FI cat back 2 weeks ago and have not had any issues. I also have the Burger Stage 1 and don't plan on tuning any time soon. Removing the secondary cats really opens things up. Waiting for the release of the AMS intakes for my next mod so I can better hear those turbos spinning.

When FI offers them, and a few people post feedback, I may get the AMS intakes. I hope they don't have the Stillen issues and are easier to install. Also need to scavange real cooler air not just from the engine compartment. Oh, and not be an oil & gause filter. So far the stock airbox stacks up VERY well. It would be nice to hear the turbos. I absolutely love the sound of my truck diesel turbo (modified intake), wish my Q has some intake sound.
 

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Discussion Starter #12
AMS Lower Down Pipes should not need a tune. It says several times on the page that they will not throw a CEL.
Now to get the most out of them you should tune, but they should absolutely work on a stock car, no tune, no CEL.


I have a set being installed Monday along with the AMS Heat Exchanger. No other mods and I'm not planning on tuning right away.
So how did it go? Do you notice any difference in driving characteristics? Does the exhaust note sound better?
Waiting to hear!:D
 

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So how did it go? Do you notice any difference in driving characteristics? Does the exhaust note sound better?
Waiting to hear!:D

I'm sorry, but I have to wait another week :( My shop is backed up because a mechanic was out sick for a week. The good news is that my Nismo exhaust arrives from DI parts today so everything will be going on at once next Monday. Now I am wishing that I bought a mid / y pipe to finish off the system.


Anyway I will let you know. I'm sure it will be great :)
 

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Discussion Starter #14
I'm sorry, but I have to wait another week :( My shop is backed up because a mechanic was out sick for a week. The good news is that my Nismo exhaust arrives from DI parts today so everything will be going on at once next Monday. Now I am wishing that I bought a mid / y pipe to finish off the system.


Anyway I will let you know. I'm sure it will be great :)
Bummer. :/ Looking forward to hearing what you think! :D
 

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Getting my Q tuned today at "The Shop" in Houston. I have FI resonated CBE and lowers. I am having them install AMS HE also. I'll share the numbers when I get them.
 

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Bummer. :/ Looking forward to hearing what you think! :D

My shop installed the AMS Heat Exchanger, AMS Lower Downpipes, and the Nismo CatBack in about 7 hours yesterday.


So far everything is great! The car has a nice growl on cold start, definitely sounds like a import, cabin noise is minimal. I did disable the Active Sound Control which I highly recommend doing.



It could be a bit louder for me under WOT, but cruising is very nice. I can probably get some more sound out of it by doing the mid / y pipes. I will leave that for later. My installer commented on how chocked off the stock exhaust seemed.


Anyway I'm very happy with everything. I can't wait to drive it more. I'm looking forward to the AMS intake, I would like to hear a bit of turbo spool.


My previous car was a Corvette Stingray and I put Kooks Headers on it (with cats). That car sounded amazing. I would say on a scale of 0 (stock) to 10 (corvette with headers) I'm sitting at around a 5-6 with the Q50 now. Not bad. I could maybe see it coming up a point with mid / y pipes and everything matched well.
 

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When I called and spoke with AMS about installing LDP's without a tune and they reccomended against it.
 

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Getting my Q tuned today at "The Shop Houston." I have FI resonated CBE and lowers. I am having them install AMS HE also. I'll share the numbers when I get them.

I wrote up my results on this thread. Short answer, I am very pleased with the AMS HE and my car has tons of torque. If I am not careful, I will lose my license. :laugh:
 

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Discussion Starter #19
Thanks for getting back!! Is there any change to the driving experience? Backpressure should decrease and even without a tune the turbo should spoil a bit more quickly. Right?
 

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Thanks for getting back!! Is there any change to the driving experience? Backpressure should decrease and even without a tune the turbo should spoil a bit more quickly. Right?
Difference? The LDP and CBE made a great difference in the quality of sound. The car seemed to drive about the same. Maybe a bit more grunt. The tune seems to have created early torque and a long flat curve above 400 between 3000 and 5500 rpm. It's a beast. The car pulls hard in any gear. The tune made the transmission shift a little more firmly and quickly in Sport+ mode. In standard mode, the car seems about the same until I get hard on the throttle. Then I better be paying attention.

For example when exiting my neighborhood, I must accelerate from stopped to 55 to blend with traffic. Most of the time the traffic only presents small holes. The asphalt is polished and I've never gotten good traction wet or dry. I used to accelerate gently to 20 and then lean on it to blend with traffic. Now however, if i get on it below 40 the car will lose traction. All that torque is new to me. I like it.

The car definitely is quicker than stock. The dyno backs that up. The power band is wide and very useable. If I were to give the butt dyno impressions, I would say about half of the difference came from the exhaust changes and the other half from the tune. The HE makes it possible to pull hard after sitting in traffic on a hot day.

Drove my son's S3 today. The S3 is quick, but it does not pull like my Q. I like mine better.
 
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