Newbie to a Turbo Engine

[mechtech2]

Just drive it as you like.

If there is no special factory device to cool or run oil through the turbo when you turn it off, then let it idle 30 seconds before turning it off. [esp. if you were thrashing it right before turn off]

 

[Thermo1223]

The only time I would ever idle to cool down is when pulling into a service plaza on the highway. As in exit ramp goes right in, even then I would only give 1 minute at he most. That is what synthetic oil is for IMO.

The less you use the throttle the better the fuel economy will be as is the same for every car. Turbocharged cars are just more sensitive to your right foot. There would be times I could get 25mpg in the Forester which was better than it should be. Others I'd get 14-15 avg.

 

[TC]

I believe possibly the shortest answer here might be that the current crop of OEM turbochargers are designed to be as "invisible" as possible, and are largely successful in that regard.

By that I mean relatively invisible in regards to when they're kicking in (there's no real turbo lag or "kick-in" for that matter with my VW 2.0T), invisible as to special maintenance issues, invisible as to special motor oils, invisible as to longevity and durability, and invisible as to special driving concerns (such as "spin-down" before shutting off an engine). Supposedly Subaru explicitly states that spin-down is not necessary for their newer rides, for example. As Hooligan pointed out, check the owner’s manual.

Back in the early 1980s when I first started track racing, turbos, even OEM turbos, were a bit more quirky, and spin-down was a more common concern. Much of this can be traced to heat. Some turbos then were oil-cooled, rather than H20 cooled, occasionally threatening temperatures comparable to Hades, or at least the surface of the sun. To shut down a mega-hot, still-spinning turbo without oil circulating could be problematic. They even marketed special "turbo" motor oils back in the day, even if that was mostly a marketing gimmick. But modern OEM turbos generally don’t go “Three Mile Island” like in the old days due to more effective cooling. Nowadays most turbos are refined to the point where they're basically....well, invisible.

 

[jigen]

Very informative posts thanks. The VW manual is pretty useless when it comes to engine or maintenance concerns (that's what the dealer is for, right?!). I am actually surprised it tells me the oil capacity, but according to some people on forums that capacity is incorrect lol.

The car definitely runs and cools the turbos down though. I am guessing it shuts down as soon it hits a certain temp since the time seems to vary.

 

[lexus114]

Originally Posted By: TC
I believe possibly the shortest answer here might be that the current crop of OEM turbochargers are designed to be as "invisible" as possible, and are largely successful in that regard.

By that I mean relatively invisible in regards to when they're kicking in (there's no real turbo lag or "kick-in" for that matter with my VW 2.0T), invisible as to special maintenance issues, invisible as to special motor oils, invisible as to longevity and durability, and invisible as to special driving concerns (such as "spin-down" before shutting off an engine). Supposedly Subaru explicitly states that spin-down is not necessary for their newer rides, for example. As Hooligan pointed out, check the owner’s manual.

Back in the early 1980s when I first started track racing, turbos, even OEM turbos, were a bit more quirky, and spin-down was a more common concern. Much of this can be traced to heat. Some turbos then were oil-cooled, rather than H20 cooled, occasionally threatening temperatures comparable to Hades, or at least the surface of the sun. To shut down a mega-hot, still-spinning turbo without oil circulating could be problematic. They even marketed special "turbo" motor oils back in the day, even if that was mostly a marketing gimmick. But modern OEM turbos generally don’t go “Three Mile Island” like in the old days due to more effective cooling. Nowadays most turbos are refined to the point where they're basically....well, invisible.



No kick? Whats the point of having/driving a turbo then?

 

[Quattro Pete]

Originally Posted By: lexus114
No kick? Whats the point of having/driving a turbo then?

In many modern applications, turbo is used to gently smooth out the torque curve.

However, I wouldn't necessarily agree with the previous poster that the turbo in VW 2.0T is invisible. I drove a 2009 GTI with that engine, and noticed some turbo lag and "kick-in". Granted, it wasn't as pronounced as some of the turbos in the 80s or even in my old '01 A4 1.8T, but the rubber-band effect was still there. It can be fun though.

 

[A_Harman]

Originally Posted By: TC
Back in the early 1980s when I first started track racing, turbos, even OEM turbos, were a bit more quirky, and spin-down was a more common concern. Much of this can be traced to heat. Some turbos then were oil-cooled, rather than H20 cooled, occasionally threatening temperatures comparable to Hades, or at least the surface of the sun. To shut down a mega-hot, still-spinning turbo without oil circulating could be problematic. They even marketed special "turbo" motor oils back in the day, even if that was mostly a marketing gimmick. But modern OEM turbos generally don’t go “Three Mile Island” like in the old days due to more effective cooling. Nowadays most turbos are refined to the point where they're basically....well, invisible.


This paragraph brings back some memories. I owned an '85 Pontiac Sunbird Turbo for 14 years and ran it in autocrosses, time trials, and track days the whole time. When I first got the car, I ran 10w30 Valvoline Turbo V, then switched to M1 5 or 10w30 after the first couple of years. This engine did not have a water-cooled bearing housing, so I was always careful to let it idle down for a couple of minutes after a lapping session or autocross run.

Chrysler's 2.2L turbo of the same era was well-regarded for having a water-cooled bearing housing, but in my opinion it was necessary because the turbo was mounted behind the engine, where cooling airflow was insufficient. The turbo on my Sunbird was mounted on the front of the engine, right behind the electric radiator fan. Over the years, I never lost the turbo due to bearing coking, but I did lose the original turbo when the snap ring holding the turbine housing to the bearing housing broke, and allowed the turbine wheel to rub on the turbine housing. This caused a LOT of turbo lag.

The worst thing about the engine was the exhaust manifold. I cracked two of the original-design welded tubular manifolds, and finally replaced it with the thick-wall cast exhaust manifold that was on the 2.0L turbo's in the last year of production.

 

[Volvohead]

Originally Posted By: jigen
Any suggestions you guys could give me as far as daily driving with a turbo compared to a NA engine?


Use good, fresh fuel. Octane no lower than the minimum recommended. Even with computer adjustment, turbo engines don't like substandard fuels.

Use upper tier premium, full synthetic oil. Service ratings no lower than the manufacturer warranty minimum. Turbos, even if water cooled, impose greater thermal and mechanical loads on an oil. Don't believe that conventional oils are just as good - at the same intervals they're not.

Don't cheat on OCs. Change the oil/filter no later than recommended by the manufacturer. Better to go shorter than longer. If you want to be sure, run a UOA or two to fine-tune the optimum interval. Otherwise, say hello to sludge.

Keep the ignition system maintained with high quality parts. Worn plugs and worn or flaky ignition components can cause major problems including damage at heavier boost levels.

NEVER continue to run a turbo engine that is overheating. It's a good way to blow them up. Shut it down and call for a tow.

Bottom line: just observe more scrupulous and rigorous maintenance habits.

Unless you're tracking it or abusing it, that is all that is usually required on a modern turbocharged street engine.

Bigger turbos have longer spool ups, and higher viscosities are not always better for them. Stick with the recommended weights unless you have a bona fide reason to change.

 

[jigen]

Thanks Volvohead. My OCI are always pretty conservative. I do every 6 months regardless of the miles (for me usally ends up around 5k).

Now this engine recommends 91 octane. Would I see benefits using 93? I heard many opinions, but majority seems to say that unless it's tuned for the higher octane it will make no difference.

Oil will be M1 0w-40. Always available, usually on sale.

 

[artificialist]

Originally Posted By: jigen
Thanks Volvohead. My OCI are always pretty conservative. I do every 6 months regardless of the miles (for me usally ends up around 5k).

Now this engine recommends 91 octane. Would I see benefits using 93? I heard many opinions, but majority seems to say that unless it's tuned for the higher octane it will make no difference.

Oil will be M1 0w-40. Always available, usually on sale.

Octane sensitivity depends on the car. Some cars will advance the timing and/or boost more when 93 is used where 91 is required, but not every time. It depends on numerous factors.

 

[TC]

Q: "No kick? Whats the point of having/driving a turbo then?"
A: "In many modern applications, turbo is used to gently smooth out the torque curve."

Perhaps a "seamless" kick is the term I could have used for the VW, at least that's my perception. That jives with Quattro Pete's comments on smoothing out the power curves. I came across some interesting comments by a Garrett engineer..."What needs to done to make turbochargers more popular in the States? I think turbos need to be tuned to “drivability” more than sheer horsepower. If you look at the turbo applications in the United States, fifteen years ago, they were basically highly souped-up, highly boosted, standard engines. If you take a different approach and used turbo-charging to increase the low-end of the engine, you’ll actually see better drivability from a two-liter engine than a three liter (non-turboed) engine: more torque, more low-end response, higher top end and better fuel consumption. American OEMs need to realize you don’t use turbos for horsepower alone, but to enhance the total driving experience."
http://www.acarplace.com/cars/turbochargers.html

AHarman’s comments about his Sunbird Turbo reminded me of a friend who track-raced a prepped mid-80s Turbo T-Bird street car (funny, huh?). His summer events were always an ongoing battle against heat….trying to keep the radiator and engine cool, trying to prevent thermonuclear meltdown with the oil-cooled turbo, installing his under-car duct contraptions at the track to steer air towards the front brake rotors, etc. I’m guessing that the single act of moving from oil to water cooling for OEM turbos may have been the greatest improvement for the breed, bar none. My poor friend didn’t have that luxury and waged war against fire and heat during every summer-month event that I recall. Those were the days…

 

[sciphi]

It's a different experience driving the same turbo engine hooked to an AT compared to a MT. With my dinky 1.4T/MT in the Cruze, it's sometimes painfully obvious when the turbo kicks in. With the AT version, it's much more seamless thanks to the torque converter doing its thing at low speeds/higher engine RPM's.

If one really wants to know what is going on, a ScanGauge II (at least version 4.15 or later) or an UltraGauge is necessary to tell boost, timing, and fuel consumption. Sometimes I glance over at my SGII and realize the turbo's really active when it wouldn't occur to me, and isn't active at other times.

Also, most OEM's have done a lot of intake tuning to reduce the turbo sounds for the average car buyer who's used to a big V6 or V8, not a little turbo 4. Those buyers might hear the bypass valve dumping boost and wonder what the blazes is causing that intermittent metallic sound that gets louder the harder they accelerate. Or, they might hear a high-pitched whistle, and wonder where the air leak is. No, sir, that's the turbo. What, this thing's turbo?!?

 

[BrianWC]

Oh man, these posts are making me miss my turbo'd cars.

But at the same time, they are making me think "Thank goodness I don't have a turbo'd car anymore!!!"

 

[Quattro Pete]

Originally Posted By: jigen
Now this engine recommends 91 octane. Would I see benefits using 93?

So you guys in PA have an option of both at the pump? Out here 91 is not an option.

 

[jigen]

Yea, some are 87,89,93 but everything I see is 87,91,93

 

[HTSS_TR]

In the west, mostly in CA, AZ, NV ... we have only 87,89 and 91. It was 87,89 and 93 in the 80's.

 

[sciphi]

All the pumps by me are 87, 89, 93 octane. I run 93 octane since there's a noticeable fuel economy benefit, enough so to make it worthwhile to not switch to 87.

 

[rationull]

I would probably run 93 octane if I had access to it. Stations only go up to 91 around here.