My new car: 2021 Audi SQ5 Prestige.

[FoMoJo]

We have normality.

Any problems with your current reality are now yours to sort out.

When did you get the Aviator?

[Morris Minor]

I'm in Lake Tahoe currently for mountain biking, which means driving at 5,000 - 9,000 feet at temps into the 90s, and my car has stumbled a few times here when getting on it - both from a standstill and when already under way - it's mos def the engine and not transmission.

Turbos have huge compromises to make WRT engine safety and emissions, and thin air and high temps only makes it more so. It hasn't happened at home however.

I quite like the turbo in the Mazda - its a rorty impertinent little bastard in ordinary housewife grocery-getter clothing.

[GoCougs]

Got the APR Stage 1 (91 octane) tune today. Throttle response and part throttle performance are improved, but the lone full throttle pull (traffic was more dysfunctional than average today) was underwhelming TBH. Turbo power bands are always underwhelming though, and the APR tune actually pushes the average power down the rev range, which probably makes it seem more so. In fact, for quickest acceleration it is recommended to shift at 6,000 rpm vs. 6,500 rpm red line (note the shift points on the graph are for a 6,500 rpm red line). I'll try both 6,000 and 6,500 rpm shift runs on Saturday night. Any guesses? Hoping to lop 0.5 sec off both the 0-60 and 1/4 mile times:

[GoCougs]

Results are in: 0-60 in 4.3 s and 1/4 mile in 12.9 s @ 104 mph.

About what I expected, though trap speed seems low for those times. Only got one run in due to conditions, so did not try short shifting. This about what it should have felt like from the factory. Now having had it for a few days, part throttle performance is significantly improved - both response and acceleration. Finally satisfied with the vehicle.

[GoCougs]

Was going to get the APR intercooler installed but they didn't have a tech available until November. Not worth much power but does give margin on hot days and at higher elevations.

[giant_mtb]

That's pretty damn quick. 

[Rich]

Faster than my old five oh, I got a 13 flat at 107 I think when I took it to the strip.

[Laconian]

Got the APR Stage 1 (91 octane) tune today. Throttle response and part throttle performance are improved, but the lone full throttle pull (traffic was more dysfunctional than average today) was underwhelming TBH. Turbo power bands are always underwhelming though, and the APR tune actually pushes the average power down the rev range, which probably makes it seem more so. In fact, for quickest acceleration it is recommended to shift at 6,000 rpm vs. 6,500 rpm red line (note the shift points on the graph are for a 6,500 rpm red line). I'll try both 6,000 and 6,500 rpm shift runs on Saturday night. Any guesses? Hoping to lop 0.5 sec off both the 0-60 and 1/4 mile times:

What's the downside? Are the tradeoffs pushing against any kind of tolerances?

[GoCougs]

Have modded many many many cars in the past, but that was 25+ years ago. Haven't touch a goddamned thing since I started buying Japanese . Nowadays most everything is turbocharged, so the methods have changed completely. Here, it was but a ~1 hour download to the ECU.

Having driven it a few days now, the part throttle response is monster - the barks and pops and thrust is a whole other level, esp. when manually shifting. There is a bit more turbo lag, which is understandable, but the net is hugely positive. No check engine light or other issue. She moves out REAL good.

Per the various 1/4 mile HP calculators, stock is ~375 hp  and tuned is ~420 hp vs. 349 hp rated. Due to the increased boost (= increase air flow obviously) the stock intake is a limitation but APR does not have an intake for the SQ5 yet (they're working on it). That, plus the intercooler, will be worth another ~30 hp judging by the S4/S5 (which APR does have an intake for).

[GoCougs]

What's the downside? Are the tradeoffs pushing against any kind of tolerances?

There is one caveat - one must ALWAYS run at least 91 octane. If one doesn't, and there is damage, APR will be able to tell, and any warranty claim will be denied. The manual says less than 91 octane can be used but only under emergency situations, and that rapid acceleration is to be avoided, so not really a big caveat TBH. Not a problem as everywhere I've ever been at least 91 octane is available.

I bought the APR warranty that stands in for the factory power train 4 year/50k mile warranty. If there were risks I'd have to think APR would not offer the warranty. The local tuner that did the tune (Actuning in Redmond, a rather large outfit actually) said of all the ARP tunes they've done they've not had one warranty claim they're aware of, and that includes a lot of RS cars.

I mined the various Audi fanboi forums, and didn't fine ONE failure or engine damage warranty denial from the APR 91 octane. The closest I found is some emissions recall claims (such as replacing cats or front radiator block off actuator) were denied but of course the owner simply ignored it because fuck you and went on his merry way.

There is a smidge of lag/hesitation when I get on it say from 2-4,500 RPM, but it's not terrible.

[r0tor]

Stage 1 turbo tuned are always great for daily driving.  They give you huge mid range improvements that feel great in normal driving.  The only downside is on engines where the turbo is small the boost tapers back down towards stock and can feel like a bit of a letdown at upper rpms.

[Eye of the Tiger]

Sucks paying for premium gas, but it's still cheaper than diesel. Wtflol.

[GoCougs]

Now that I've got the mod bug, I'm lined up for the APR intercooler and hopefully the APR air intake (not sure it's available yet - might be the same as the S4/S5).

The IC gives 10-15 hp across the range, and the intake adds power (10-15 hp) only after 4,500 RPM, which is great, as that is when the tune starts to notable taper off. Average power increase will be ~75 hp and peak of ~125 hp.

The tuning shop is crazy busy, so it'll be a couple more weeks before they can fit me in.

Car's pretty fast but TBH I'm still a bit insecure about it - the full stage I should drop another 0.1-0.2 s from both 0-60 and 1/4 mile.

[Eye of the Tiger]

Does Eisenmann make an exhaust for that? That's what it needs.

[GoCougs]

Actually, the factory exhaust with the Audi add-on factory exhaust tips is one of the best sounding turbo exhausts out there. It's also very loud - any louder would be too much.

[Eye of the Tiger]

That's strange. Most stock Audis are pretty quiet.

[GoCougs]

Short vid (not my car) - cold start, warm start, and sporty-ish driving. She snorts, cracks and pops quite good.

Under the car there's a flap that closes the left side pipe except for sport mode above like 4,000 RPM. I disabled that of course and that adds some sound too.

https://www.youtube.com/watch?v=m1fDqVJjLrQ

[GoCougs]

Another update. Things have not gone so well with APR.

Firstly, I bought the APR intercooler, and it was a fucking disaster. I get the entire front of the car torn apart only to discover the mounting brackets were wrong. And taking apart a modern car is rough - the fasteners for pretty much everything are not meant for repeated use, and many are not replaceable, so all that stuff takes a beating. There's even Styrofoam! So much as look at it, and it breaks. Can't see it from the outside but I know the sins lurk beneath. Ugh. Anyway, finally got the right brackets for a 2nd install atempt only to discover they didn't design/manufacture pressure sensor housing correctly. The factory housing has a beveled edge to ease in the o-ring - no such bevel on the APR housing, and I sheared off the outside of o-ring. Not trusting the damaged o-ring, nor the o-rings I tried off of Amazon, I had to buy a new $150 sensor. Plus of course I beveled the APR housing to about match that of the factory housing, and all went together like a champ.

Secondly, we have rare cold weather here (20-35F) and performance has dropped noticeably. From a roll, I'm now a bit slower than stock. Countless tests and data logs later (and $500+ in tools and test parts) and APR came back NPF, with the likely cause weird-ass environmental conditions the tune can't exploit, or maybe our winter gas is REALLY bad, or maybe traction issues. I mos def have a hesitation on shifting at full throttle too, which may be the cause of it all. Some say it may be torque throttle to protect the transmission due to the extra power being made at such advantageous atmo conditions, but that seems like a stretch. Anyway, hot rodding today is just like it was way back when I did it - the tech has changed but it's still the same - you're mostly on your own to figure it out (or not) and there are compromises so that's why automakers don't do it themselves.

Will not tune again.

[giant_mtb]

Yeeeeep. Always make sure to have a stash of those one-time-use fasteners on hand when taking apart any modern car. Especially the front end where it's all clips and shit holding it on.

[GoCougs]

Yeeeeep. Always make sure to have a stash of those one-time-use fasteners on hand when taking apart any modern car. Especially the front end where it's all clips and shit holding it on.

I always have on hand the generic plastic push pins like those used for fender liners. I got caught out on single-use fasteners (as stated in the Audi documentation) that fastens the wheel trim to the fender - they're super brittle and break when pulling off the trim. Audi-only, and $4 a piece! There are also a number of fasteners that for wiring and tubing on the front bumper cover that are also Audi-only (they're plastic w/metal barb inserts). They didn't break but they tear up the plastic they have to be pulled off from. Ugh.

[r0tor]

Does APR do a transmission tune as well as the ECU or just the ECU?  The ZF transmission controller definitely has torque limits buried in it.

In the Alfa world piggybacks are working better than ECU tunes due to all the limiters buried everywhere - even for fairly large changes like running larger turbos.

[RomanChariot]

I'm not surprised the fasteners were brittle. I used to work with vinyl fabric coming out of Germany. Germany outlaws plasticizers almost as fast as the manufacturers can create them, so many of their plastics ineffective or relatively unproven plasticizers. And in the case of our product they thought it was okay to change plasticizers without letting us know so we were blindsided with major problems with our end product.

[GoCougs]

Does APR do a transmission tune as well as the ECU or just the ECU?  The ZF transmission controller definitely has torque limits buried in it.

In the Alfa world piggybacks are working better than ECU tunes due to all the limiters buried everywhere - even for fairly large changes like running larger turbos.

No, not yet. They're working on it and should be out soon. They said the factory has all sorts of torque limits, esp. for shifts, where I seem to be having a problem (though not sure that's what's causing my issue).

If I'm at -25F or something crazy, I could believe that being outside the tune's capabilities, but are my atmo conditions affording that much more power such that the transmission needs throttling back? Hard to imagine, but as viable an explanation as anything else.

In the next day or two I'm going to data log stuff related to torque limits to see if something looks interesting.

[GoCougs]

Charted measured motor torque (not sure how the car does that however). At the shift points noted, the torque virtually exactly matches the published APR torque curve so thankfully the engine's at least making the tune's advertised horsepower.

At the shift points (three big dips) engine torque is well under maximum permissible for the transmission (406 lb-ft as listed via OBD-II inquiry) so I doubt it's a torque throttling to protect the transmission, plus the forum I'm on guys are running WAY more power and no one complains abourt throttling.

The timing chart mirrors this chart - timing is cut hugely at each of the three gear shifts. APR says that's normal, to ease the harshness of shifts - thing is I'm in "sport" mode...

Wheel speed graphs (not shown) show no traction loss, but they do show the hesitation at gear shifts.

So, the conclusion I draw from this is the hesitation is what is killing performance (duh, no surprise). Revised my report and sent off to APR.

[GoCougs]

RESOLVED.

Soon after purchasing the vehicle I disabled the actuator that opens/closes the flap in the driver's side exhaust tip. It bothered me to no end to see only one side emitting vapor on a cold morning! The actuator was still plugged into the wiring harness but a fault code was generated nonetheless (but no CEL - I could only see the fault code via an OBD-II reader). I figured it didn't hurt nuthin' so left it alone. Yesterday, just as a normal course of finding an excuse to work on cars, and no inkling that this would fix my problem, I installed a connector disable kit that tricks the ECU into thinking the actuator is working correctly. I then reset the code, and sure enough, that 100% fixed the problem, and now she is absolute screamer. Note the problem followed the code (which takes a bit of time to appear - I'm guessing the ECU needs to see a number of failed attempts to open/close the flap) and not the actual state of the flap. Also note I had this actuator was disabled prior to the tune and I did not experience any shift hesitation or bog as I did after the tune. So relieved. JMFC. Why this tripped up the tune I have no clue. LOL look at those times, and mind you, I was spinning a bit on launch due to snow tires, so there's probably 0.1 - 0.2 s still left in it:



The other interesting tidbit is after I had the tune installed the tuner reset the fault code. I then did my acceleration testing. I had incorrectly presumed the correlating factor was temperature. Temps were in the 50s deg F when the tune was installed, and I tested again at 28 deg F.

[AutobahnSHO]

TL;DR you outsmarted the engineers over an annoyance and crippled your car???   

[GoCougs]

Got further info why from APR as to why the exhaust flap fault was pulling so much power: If the ECU doesn't know the state of the flap it presumes worse case (that it is closed) which at load can quickly lead to dangerously high exhaust gas temps, and the ECU will automatically pull power to be safe.

One very popular hack is to buy "delete" connectors that plug into the harness to convince the ECU that the flap is okay even though it's unplugged. One still gets a fault code (= electrical error) but apparently it doesn't affect power in any way . I thought I'd be crafty and simply mechanically disconnect the motor from the flap but leave it plugged into the harness. Turns out this caused a different fault code (= motor moving but flap was not closing) which cuts power per the above.

Quick-n-dirty charts showing before/after fix. Turns out it was costing me ~5 psi (27 vs. 32 psia) or about 5/27 = 19% peak power vs. tuned (410 hp tuned to 330 hp, or a bit slower than stock (350 hp) which is exactly what happened). Boo a bit on APR for not seeing that boost (both actual and specified) was significantly under spec for their tune. Should have been easy to spot.

Pretty much no one offers stage 2 hardware for the SQ5 (and it's way emissions illegal anyway) so this as far as I'll take it. Once the temps warm up and I can get better traction I expect 4.1/12.5 performance. Not bad really. I'll give it another year, to wait for the next crop of Audi product. I'm guessing it'll be a lot of EV or hybrid stuff, so will probably default back to the RS6 Avant.

[AutobahnSHO]

Very quick! That is pretty crazy they didn't spot that in testing.

[r0tor]

It's sort of frustrating these days as your ECU can be storing codes that are only seen with high level diagnostic tools.  Simple OBD2 checks don't show them.

[GoCougs]

She's movin' now, boys!

Had to revise my launch method - emergency stop from about 80 mph to heat up the tires, then pump the brakes till the pedal goes dead (= max pressure) then skooch the driver seat way forward so that I can get max leverage/force on the brake. Even then I'm still getting some wheel spin and ~50% of the time I'm still pushing through the brakes (which negates sport shifts). But when she works, she works. I'll have to wait for warmer temps and my A/S tires to do better. I figure there's probably another 0.10 sec in her but satisfied with this. I've had the tune working correctly for ~2 weeks now, so I think there's been some ECU learning that has picked up some power as well: