A Little-V Blog: The ATS-V purchase and ownership experience

[Hib Halverson]

If one can forget to push the button, one can forget to turn the key ... I wonder how many cases of that never made the news... Frankly, I wonder if people who can't remember to turn the car off need to be driving in the first place ...

I get it about people who can't remember to turn off the car, but...the other side of that is for over 50 years, people were used to putting their keys in the ignition and leaving them there for the duration of the drive then having to shut the car off to get the keys out. I know there were really old cars you could start then remove the key while they were running but that ended in, I believe 1964 for GM.

Also, we don't NEED push button start just like we don't NEED an electric parking brake. Yeah, some make like it, but it's unnecessary. It's just more evidence that marketing weenies and techno-geeks are making choices for us.

Finally, back to the issue of people who can't remember to turn off push-button-start-cars shouldn't be driving...

You might feel differently about that if you were 65+ years old and experiencing some hearing loss. My guess is the unfamiliarity of push-button-start combined with partial hearing loss might have been at the crux of the problem...well, also, tightly fitting windows in their house, too.

 

[nbtx]

and now for something completely different

If enough geezers forget to push the start button to shut down when done driving, the NHTSB will probably mandate an
interlock that will lock the doors until you shut the engine down. Think I'm kidding? The fed gov nannies never sleep.

Damn the start button and electric park brake ... my Acura TSX had the PB lever in the middle of the console and it was the best assist grab for getting in and out of the car. And the system of interlocks, door handles and start button in my C6 Corvette baffle the mind - just because the engineers could doesn't mean they should have. YMMV.

Glenn

 

[Hib Halverson]

I'm starting to get a picture of why the very first "tuners" who've worked on an ATS-V might be seeing some significant increases.

It's starting to look like GM "left some on the table" calibration-wise.

For one thing, in the data logging I've done, in three WOT acceleration tests in 3rd gear up to 6300 rpm, when the engine computer is in "power enrichment" (PE) mode, I saw the "commanded EQ ratio" (which is sort of like the air-fuel ratio) hovering at 0.909-lambda which is pretty lean. If the car is running on pump gas with no ethanol in it, the stoichiometric AFR is about 14.68:1. At 0.909-lambda, that's 13.3:1 which is pretty darn lean. Why that is so lean is up for speculation, but reduced carbon emissions might be one reason. So, if a calibrator was to add some fuel in PE such that the commanded EQR was down around 0.87-0.86, there might be some power there.

Also, at max boost and high rpm, the spark timing is retarded quite a bit, as low as 8°. There might be some power there, too, but there'd also be big problems with knock retard if you were running pump gas so, the only way to run the engine with more spark and minimal KR would be on 100-oct. unleaded racing gas which...for most people, is not very practical nor cost effective.

Another idea might be to improve the efficiency of the charge air cooler. You could do that by increasing the size of the heat exchangers but that would not be easy. You could jury-rig a water spray system for the two radiators. You also could decrease or even eliminate the use of antifreeze in the separate cooling system used by the charge air coolers. Water is a better coolant than a 50/50 mix of water/antifreeze. To do that requires special equipment because, to fill the charge air cooler system you have to apply a vacuum to the system, first. Obviously, if you park the car overnight or store the car in a place where it gets below freezing you can only reduced antifreeze to a level of freeze-protection you need.

Fooling with the boost limit might gain a bit but the turbos can only make 18-psi which is just a few psi more than what most people are seeeing now. If you increase boost you also need to either increase the performance of the charge air coolers or increase the octane of the gas.

Down pipes without cats would pay off in a big way I suspect.

Some other things I've noticed...

Now that I can read trans temperature, the 8-speed auto must have a gynormous cooler as I've yet to see trans. temp over 150°F.

Next thing to do to "Pearl the Bimmer Buster" is to install a clear bra on the front end. I'm considering XPEL installed by Transhine Auto Detailing in Whittier California for the job.

I'd also like to put in some colder spark plugs but, looking at all the stuff on top of the engine's cam covers, I'm thinking plug changes on the LF4 are a lot of work.:frown:

Some people have asked if I'm going to change the exhaust on the car. I haven't decided, yet. My experience with dual-mode exhausts on C6 Vettes has been that few, if any, aftermarket exhaust makers make a system which leaves the bypass valves intact and operational. If the aftermarket goes that route with the ATS-V, I probably will not go aftermarket with exhaust.

 

[Djason]

Yep agree Hal...looks like quite a bit is left on the table from the stock tune not to mention the horrible angles and bottle necking of the stock cats and exhaust.

Would love to see the Titanium Akrapovic system for the ATS-V. Doubt they will do it but I'm extremely happy with the workmanship and materials used for the system on my Z06. Can literally pick one side up with a finger. And yes it keeps the dual-mode valves. You have to swap your actuators but the mounting and valves are part of the mufflers.

Fully installed with their smallest (115mm) tips. The sound is spot on.

 

[~tc~]

Lowering the air/fuel will not make more power. Max power is made at stoich. Want to make more power - need more air to burn more fuel, or increase the compression ratio - simple as that.

Richening the mixture MAY allow for increased boost or timing due to lower EGT, and if so, that would generate more power.

The turbos are certainly capable of a lot more than 18 psi, just keep the waste gates shut. The issue is how much boost can the head take before blowing the gasket.

For all Cadillac's talk about gram phobia, they sure left a lot of weight on the table - the Ti exhaust is a great example.

 

[Hib Halverson]

Lowering the air/fuel will not make more power. Max power is made at stoich. Want to make more power - need more air to burn more fuel, or increase the compression ratio - simple as that.

I'm sorry "~tc~" but you're wrong. "Stoichiometric" is where combustion is most efficient but a stochiometric air:fuel ratio is not one which provides the most power. If the fuel is "straight" gasoline, max power is made at somewhere between 12.5 and 13:1 AFR. If you're burning ethanol-blended gasoine–so-called "E10"–which usually has 7-8% ethanol, you need to be down about 11.8-12.3:1.

Richening the mixture MAY allow for increased boost or timing due to lower EGT, and if so, that would generate more power. The turbos are certainly capable of a lot more than 18 psi, just keep the waste gates shut.

I think you may have misunderstood what I said. so let me restate, the compressors used on the LF4 are capable of 18-psi with no waste gates.

The issue is how much boost can the head take before blowing the gasket.

Now, you're talking combustion pressure not manifold pressure.

For all Cadillac's talk about gram phobia, they sure left a lot of weight on the table - the Ti exhaust is a great example.

I didn't quite understand what you mean. The LF4 does not have any titanium exhaust parts but it does have titanium connecting rods

 

[Hib Halverson]

Would love to see the Titanium Akrapovic system for the ATS-V.

Super nice exhaust but also super expensive. Out of my league for sure.

 

[Djason]

Super nice exhaust but also super expensive. Out of my league for sure.

Agree...that's why I only did the axle-back section and kept my KOOKS intermediate pipe.

If they could do the section between our cats and muffler it might be doable. Keep the stock muffler, some quality down pipes to replace the jacked up, horrible flowing cat exhaust, and sandwich the Akrapovic. That would be a killer system "IF" it had a quality/tuned V6 sound...not fart-pipe obnoxious with the cats gone.

 

[Hib Halverson]

Well...living in the Demokratik People's Republik of Kalfornia, I have to keep cats on the car.

I have always wanted to build a Flowmaster exhaust for my C6 Z06 because I've always liked the Flowmaster sound. I have a design in my head which would use Flowmaster mufflers and also the stock bypass valves. Problem is I need to have an exhaust fab-guy build the system and I need some serious money to have that done. As for the ATS-V, I'd like to do the same with it, too–put FLowmasters on it. I will say that, after driving the car for several weeks, the ATS-V's dual mode exhaust is pretty aggressive when the car is in the sport or track mode.

Ok. Now, moving on to spark plugs.

Typically, I run colder spark plugs in all my high performance engines. GM picks fairly hot plug heat ranges because it has to contend with all kinds of drivers and all kinds of duty cycles. Our ATS-V will likey never see frequent starts-without-warm-up, which is the one type of duty that often fouls plugs. In fact, one reason most car companies put warm plugs in stock engines is to deal with so-called "pre-delivery fouling". This is caused by dealers which frequently move cars around their lots but don't actually drive. The engine gets started, the car is driven a few hundred yards then the engine is shut off. A dealer may do that dozens of times before seling a car. Engines in cars treated like that need hot plugs to keep from fouling plugs and having customers complain. The 3.6 TT in "Pearl the BMW Buster", won't be driven like that so I want to put in a set of Denso Iridium Power plugs which are one heat range colder than stock. I ordered a couple of boxes of Denso ITV-22s from Denso.

The first time I looked under the little Caddy's hood a couple of weeks ago, I noted that packaging around the cam covers is really tight. In fact, after that first look under there, I began to sour on changing plugs because of the apparent difficulty of getting around the turbocharger plumbing to reach the #2 and #5 spark plugs. Yesterday, I went poking around under the hood, again, but this time I removed the engine's beauty cover to get a better look at spark plug access.

Well...maybe it's not going to be so tough a job. If I remove the plastic assembly which is atop the intake plenum, then remove the bolts holding the turbo inlet pipes to the intake plenum, it looks like I can push the turbo inlet pipes out of the way enough to access those two spark plugs. I just need to find out if whatever seals those turbo inlets to the plenum can be reused or has to be replaced.

 

[Tuna]

What does the service manual say?
Is if available yet?

 

[~tc~]

I'm sorry "~tc~" but you're wrong. "Stoichiometric" is where combustion is most efficient but a stochiometric air:fuel ratio is not one which provides the most power. If the fuel is "straight" gasoline, max power is made at somewhere between 12.5 and 13:1 AFR.

I didn't quite understand what you mean. The LF4 does not have any titanium exhaust parts but it does have titanium connecting rods

Several years of study in compression engine thermodynamics says BS. You can't make more power by sending unburned fuel out the exhaust. If anything, you want to be slightly LEAN specifically to ensure that all the fuel gets burned. Tuners run rich NOT to make more power, but to deal with issues from the high EGT... Which are good up to a point in a turbo engine, and then really expensive if too hot.

I was referring to the entire exhaust system. A full titanium exhaust saves a TON of weight, and yet they didn't do it. Titanium suspension springs also - both of these have been proven reliable in production vehicles and the cost is pretty inconsequential at the new Caddy prices.

 

[Hib Halverson]

What does the service manual say?
Is if available yet?

Paper service manuals are not available yet. I have to go to a dealer and sweet-talk them into letting me read SI. I haven't been down there yet to do that for the plug change procedure.

 

[Hib Halverson]

Several years of study in compression engine thermodynamics says BS. You can't make more power by sending unburned fuel out the exhaust. If anything, you want to be slightly LEAN specifically to ensure that all the fuel gets burned. Tuners run rich NOT to make more power, but to deal with issues from the high EGT... Which are good up to a point in a turbo engine, and then really expensive if too hot.

I was referring to the entire exhaust system. A full titanium exhaust saves a TON of weight, and yet they didn't do it. Titanium suspension springs also - both of these have been proven reliable in production vehicles and the cost is pretty inconsequential at the new Caddy prices.

Here's what I suggest, "~tc~": you should prove your point. If you are sucessful, I'll change my mind.

To do that, you need to recalibrate the ECM in your car to change all the PE values to whatever value is in your calibration for stiochiometric air-fuel ratio. For gasoline, it's usually 14.68:1 but it sometimes varies slightly.

After you make that change, the engine hard and tell me what happens.

 

[~tc~]

... Or you could open just about any thermodynamics textbook and learn what science has known for a couple hundred years now.

Just about all factory tunes are rich, and just about all aftermarket tunes are leaner - that's where the power comes from in "high octane" and NA "tunes"

From your questions on the "other" forum trying to pilfer various firms tuning work (and all have declined) I understand you will eventually be tuning your ATS-V. I assume this will be done on a reputable dyno to ensure you're not wasting your time based on a potentially unreliable "butt dyno". As part of that process, I assume you will be trying different settings, it is a simple matter to simply plot the power against the A/F ratio.

 

[Djason]

Don't have a dog in this hunt but here's some info from people "in the know".

Air/Fuel Ratio tuning:Rich vs Lean | Turbobygarrett

Why lean makes more power BUT is dangerous

When discussing engine tuning the 'Air/Fuel Ratio' (AFR) is one of the main topics. Proper AFR calibration is critical to performance and durability of the engine and it's components. The AFR defines the ratio of the amount of air consumed by the engine compared to the amount of fuel.

A 'Stoichiometric' AFR has the correct amount of air and fuel to produce a chemically complete combustion event. For gasoline engines, the stoichiometric, A/F ratio is 14.7:1, which means 14.7 parts of air to one part of fuel. The stoichiometric AFR depends on fuel type-- for alcohol it is 6.4:1 and 14.5:1 for diesel.


So what is meant by a rich or lean AFR? A lower AFR number contains less air than the 14.7:1 stoichiometric AFR, therefore it is a richer mixture. Conversely, a higher AFR number contains more air and therefore it is a leaner mixture.


For Example:
15.0:1 = Lean
14.7:1 = Stoichiometric
13.0:1 = Rich


Leaner AFR results in higher temperatures as the mixture is combusted. Generally, normally-aspirated spark-ignition (SI) gasoline engines produce maximum power just slightly rich of stoichiometric. However, in practice it is kept between 12:1 and 13:1 in order to keep exhaust gas temperatures in check and to account for variances in fuel quality. This is a realistic full-load AFR on a normally-aspirated engine but can be dangerously lean with a highly-boosted engine.


Let's take a closer look. As the air-fuel mixture is ignited by the spark plug, a flame front propagates from the spark plug. The now-burning mixture raises the cylinder pressure and temperature, peaking at some point in the combustion process.


The turbocharger increases the density of the air resulting in a denser mixture. The denser mixture raises the peak cylinder pressure, therefore increasing the probability of knock. As the AFR is leaned out, the temperature of the burning gases increases, which also increases the probability of knock. This is why it is imperative to run richer AFR on a boosted engine at full load. Doing so will reduce the likelihood of knock, and will also keep temperatures under control.


There are actually three ways to reduce the probability of knock at full load on a turbocharged engine: reduce boost, adjust the AFR to richer mixture, and retard ignition timing. These three parameters need to be optimized together to yield the highest RELIABLE power.

 

[~tc~]

Between the cooling effect of the injection and the fact there just flat out isn't fuel in the cylinder (especially when combined with the purging effect of forced induction) in a direct injected engine, knock is near impossible.

My original post said a different way, if your engine needs to be tuned off stoich to make max power, there are additional opportunities to address to make even more power - for example, cooling the intake charge either by intercooling or meth/water injection.

 

[Djason]

It is a different ball game when comparing DI to Port Fuel inj...

 

[Tuna]

My Caddy dealer has a white ATS V Coupe sitting outside their front doors today when I had my CTS V Wagon in for routine service. Dark blue interior as I recall and MSRP of 72,000 even.

One of the sales managers pimped my about trading my V Wagon in but they don't have enough money to get me to trade the V Wagon - YET!

They wouldn't let me test drive the ATS V either. Oh well. Some other day perhaps.

 

[Hib Halverson]

My Caddy dealer has a white ATS V Coupe sitting outside their front doors today when I had my CTS V Wagon in for routine service. Dark blue interior as I recall and MSRP of 72,000 even.

One of the sales managers pimped my about trading my V Wagon in but they don't have enough money to get me to trade the V Wagon - YET!

They wouldn't let me test drive the ATS V either. Oh well. Some other day perhaps.

Seriously....?

The dealer from whom you've purchased Vs in the past would not let you test drive their ATS-V?!
I'd have been pissed. And gone to talk to the General Manager.

I had mine out today, practicing 0-60s. Damn...I love that car with the 8-spd for straight line stuff.

I was at SEMA last week and surprisingly, there was not a lot of interest or awareness of the ATS-V amongst some of the aftermarket companies I talked to. Volant claims to be working on an air box but when I asked specifics, what they described as being in development was for the regular 3.6 in a non-V. CORSA has said they might be interested in doing an exhaust if they were sure the sales numbers would be there. Green Filter wants to do cotton-gauze filters for the car but I think they are going to have a tough mountain to climb as the filters used in the stock airbox are really weird. New Era Performance has prototyped an intake kit, non-cat down pipes and has done some tuning work.

 

[Rob]

From your questions on the "other" forum trying to pilfer various firms tuning work (and all have declined) I understand you will eventually be tuning your ATS-V. I assume this will be done on a reputable dyno to ensure you're not wasting your time based on a potentially unreliable "butt dyno". As part of that process, I assume you will be trying different settings, it is a simple matter to simply plot the power against the A/F ratio.

Let me get right to the point....what exactly is your problem here?