Chris Harris: Dear Automakers, Please stop making turbos suck

[Yaj Yak]

Are they really that bad? Wifey has one, I told my self if it ever went out I'd find an upgrade if it wasn't a warranty job.

As for this guy, I can see where he's coming from. Then again people get nostalgic about "super quick" SBCs with a 3/4 race cam some double humps and headers too.

In terms of power, area under the curve is where it's at for virtually anything but a drag car. A side effect of the 80s was the downsizing of turbos to reduce the "lag" such as the Garretts on Turbo Coupes going to the much smaller IHIs, or using choking turbine housings etc. We have overcome a great deal of that with better turbos, better computers, better flowing/better combustion engines and a better understanding of how the systems interact. Why fuck with a good thing in that regard?

It does leave the question of "how much power is being left on the table for the response that's being achieved?" I don't have the answer to that, but I wouldn't be surprised if compared to 10-25 years ago the percentage is significantly less.

ED:If I ever get off my ass/care to get off my ass/actually get off my ass and work on my turbo vehicle, this is something I have actually pondered at a level. I have a T66 here I swiped from Mook that would make good power, be responsive and fun. Then again, I have a turbo here from a Detroit that's ludicrously sized, probably act like an over cammed engine with my current combo etc. I'm still leaning towards/considering the over sized one just due to what he's talking about in defiance of common sense.

fucking nailed it.

 

[Stink Star]

Cruze LUJ motors aren't bad for their intended purpose, being an economy car. But for modding they are terrible. And also if you don't take care of oil changes things go bad very fast. Unfortunately a Cruze is considered an entry level car and with entry level cars come entry level buyers and owners. People that don't change the oil destroy those things like you wouldn't believe. Also starting it up in the dead of winter and immediately driving off full boost seems to be a common thing for some owners. I've replaced hundreds of water pumps and dozens of turbos and oil coolers on them.

 

[Gone_2022]

Cruze LUJ motors aren't bad for their intended purpose, being an economy car. But for modding they are terrible. And also if you don't take care of oil changes things go bad very fast. Unfortunately a Cruze is considered an entry level car and with entry level cars come entry level buyers and owners. People that don't change the oil destroy those things like you wouldn't believe. Also starting it up in the dead of winter and immediately driving off full boost seems to be a common thing for some owners. I've replaced hundreds of water pumps and dozens of turbos and oil coolers on them.

I feel like that should be common sense.... But then again maybe not. Hey it's 15 degrees out I just started my car, maybe I should let it warm up and keep it under 3k rpms.

I've heard the turbo actuators go bad? I have the Eco Cruze and everything is good so far @ 66k miles. But I change my oil every 3-5k miles. Well before any percent olm light comes on. Maybe that's why mine is doing well

 

[SHARKBITEATTACK]

I like turbos when they are used as a "power adder" not when they are used to replace displacement.

 

[Pewter-Camaro]

The MFG's are pushing it too far to super low rpm quick spool diesel truck like power these days. For Fuck sake the EcoBoost Mustang stock has a powerband that looses steam by 5000 rpm and a pointless redline at 6500 with a stock tune that struggles to keep the boost to single digits below 3000 rpm. When it does let the turbo really spool to 18-20 psi it runs out of steam by 5000. Its such a waste to use a super quick spooling turbo then tune it to keep it from making boost 75% of the time and it just plain old sucks to run the car out to redline. Ford could have Moved a ton more Ecoboost Mustangs if they used a turbo in that would actually make power all the way to redline gave it a little lag and a more natural turbo feel. As it is now every review of the car has a comment about the car falling on its face above 5000 rpm. There is no Balance to the engine at all. Tuned its a different story but you have to change the WOT shift points because the stock turbo will never be worth a shit above 5200.

 

[Stink Star]

I feel like that should be common sense.... But then again maybe not. Hey it's 15 degrees out I just started my car, maybe I should let it warm up and keep it under 3k rpms.

I've heard the turbo actuators go bad? I have the Eco Cruze and everything is good so far @ 66k miles. But I change my oil every 3-5k miles. Well before any percent olm light comes on. Maybe that's why mine is doing well

Well actuators don't go "bad", the rod hogs out the hole on the actuator flap and can't properly control boost. IIRC GM finally came out with a replacement kit for the arm instead of just replacing the whole turbo

 

[Gone_2022]

Well actuators don't go "bad", the rod hogs out the hole on the actuator flap and can't properly control boost. IIRC GM finally came out with a replacement kit for the arm instead of just replacing the whole turbo

Correct sorry this is what I was referring to

 

[Eagle]

We have overcome a great deal of that with better turbos, better computers, better flowing/better combustion engines and a better understanding of how the systems interact.

Don't forget not being as scared to use compression AND boost together!

I'm still leaning towards/considering the over sized one just due to what he's talking about in defiance of common sense.

I applaud your defiance, good sir!

 

[jason05gt]

This article is as the British say, rubbish. Technology in the case of turbocharging is a good thing. Relishing turbo lag is akin to old carb'd muscle car owners complaining about fuel injection. I've got a EcoBoost V6 and the power is linear and nearly instantaneous, which is how it should be. The exotic cars that Harris mentioned would get annihilated by today's modern engines. For example, the F40 would get worked by the 488gtb at half the cost (not factoring in inflation) and with all the modern safety and creature comforts.

 

[Yaj Yak]

This article is as the British say, rubbish. Technology in the case of turbocharging is a good thing. Relishing turbo lag is akin to old carb'd muscle car owners complaining about fuel injection. I've got a EcoBoost V6 and the power is linear and nearly instantaneous, which is how it should be. The exotic cars that Harris mentioned would get annihilated by today's modern engines. For example, the F40 would get worked by the 488gtb at half the cost (not factoring in inflation) and with all the modern safety and creature comforts.

this all entirely subjective though of course.

driving something with a carb, fuck, driving something with a mechanical throttle blade, at this point, is enjoyable in a different way to different people.

 

[Eagle]

 

[Diavolo]

The MFG's are pushing it too far to super low rpm quick spool diesel truck like power these days.

This was the problem on my MS3. You can hit full boost by 3000 rpms, but run out by 5500. The instant boost was causing overboost, where it'd spike up to 21psi before settling back down to 18 or so and causing 'zoom zoom boom'.

Most of us would try to tune it out as much as possible, but you can only do so much.

 

[Mr_Roboto]

Don't forget not being as scared to use compression AND boost together!

I applaud your defiance, good sir!

gah it may not be defiance. That T66 looks real damn good from where I'm sitting considering my "big" turbo is a fuckin TMF5502 (think 71mm S400.) I'd need more cam than I have currently and way more than a stock converter which is coin for a 4L80E. As I said, back to area under the curve. I will say it would be kinda sad to have Mook's turbo from his puny 3.0L on my 5L small block. :rollpicard:

ED:

So, you mean like how I beat it when I drive it (the Cruze.) Have you seen anyone upgrade the turbos on these yet, I noticed that they make one with a larger comp and clipped turbine. Seems like it could cure a bit of the issue really. Based on the way you guys describe it they're totally back to the 80s again. Is there any way to escape the "turbofold?"

 

[jason05gt]

this all entirely subjective though of course.

driving something with a carb, fuck, driving something with a mechanical throttle blade, at this point, is enjoyable in a different way to different people.

The feeling it gives you is subjective, but power under the curve is measurable. The reason why cars had lag in the day was primitive tuning, fuel supply (pump and injector) and the turbo itself. Progress and technology is a good thing, particularly in the case of forced induction.

 

[Thirdgen89GTA]

This article is as the British say, rubbish. Technology in the case of turbocharging is a good thing. Relishing turbo lag is akin to old carb'd muscle car owners complaining about fuel injection. I've got a EcoBoost V6 and the power is linear and nearly instantaneous, which is how it should be. The exotic cars that Harris mentioned would get annihilated by today's modern engines. For example, the F40 would get worked by the 488gtb at half the cost (not factoring in inflation) and with all the modern safety and creature comforts.

Though this is true,

I would still bow before the awesomness of the F40.

 

[Bru]

What a whiny column.

Just

 

[Xfirez51]

I can agree that turbo lag can be sort of a fun thing. A much diminished version of afterburners on a jet. But for driving, particularly in traffic, I need to know the power is NOW if I need to squirt into a space. That lag can seem like an eternity.
I appreciate more that the acceleration you get is directly proportional to the movement of the accelerator pedal in real time. That is instantaneous as if your car responds at the speed of thought.

 

[Yaj Yak]

The feeling it gives you is subjective, but power under the curve is measurable. The reason why cars had lag in the day was primitive tuning, fuel supply (pump and injector) and the turbo itself. Progress and technology is a good thing, particularly in the case of forced induction.

i can agree with most of that.... my car has a slight lag but from a roll when it downshifts, it's unnoticeable, and you're fucking going once it hits 15psi.

 

[Thirdgen89GTA]

Gotta love power under the curve. Look at all that torque in the highway cruising power band.

Also gotta love datalogs. In the graph below I wanted to show the charge temp's because the Focus ST's intercooler is...well, its crap. Look at the delta-temp rise.

But with the excel data I can see just how long it took for the engines boost pressure to rise to pre-shift levels.

I shift the car in about .4 seconds (400ms for the sciency people). Its a regular shift, clutch in while releasing throttle, already moving shift knob, release clutch at same time as slamming foot back into floorboard. I don't think thats all that bad really for a full shift. But the boost pressure drops off pretty fast, and takes about half second to go from 16psi, to 0, then back to almost but not quite 16psi.

Time (s)	MPH	ThrBld%	PSI	RPM
1048.363	78.4	100	16.95	5775
1048.440	78.9	100	16.82	5823
1048.516	79.4	016	16.73	5840
1048.599	79.4	000	15.99	5907
1048.674	79.0	000	-3.58	6158
1048.765	78.8	060	-10.38	6090
1048.839	78.8	100	0.33	6037
1048.923	79.4	100	5.46	5917
1049.006	79.2	100	6.3	4280
1049.084	79.6	100	9.7	4784
1049.172	79.9	100	14.55	4504

 

[Mr_Roboto]

Gotta love power under the curve. Look at all that torque in the highway cruising power band.

Also gotta love datalogs. In the graph below I wanted to show the charge temp's because the Focus ST's intercooler is...well, its crap. Look at the delta-temp rise.

But with the excel data I can see just how long it took for the engines boost pressure to rise to pre-shift levels.

I shift the car in about .4 seconds (400ms for the sciency people). Its a regular shift, clutch in while releasing throttle, already moving shift knob, release clutch at same time as slamming foot back into floorboard. I don't think thats all that bad really for a full shift. But the boost pressure drops off pretty fast, and takes about half second to go from 16psi, to 0, then back to almost but not quite 16psi.

Time (s)	MPH	ThrBld%	PSI	RPM
1048.363	78.4	100	16.95	5775
1048.440	78.9	100	16.82	5823
1048.516	79.4	016	16.73	5840
1048.599	79.4	000	15.99	5907
1048.674	79.0	000	-3.58	6158
1048.765	78.8	060	-10.38	6090
1048.839	78.8	100	0.33	6037
1048.923	79.4	100	5.46	5917
1049.006	79.2	100	6.3	4280
1049.084	79.6	100	9.7	4784
1049.172	79.9	100	14.55	4504

That brings up another extremely valuable point. For those who use manual boxes instead of auto shifters you're waiting on boost to catch up again. Makes life nicer to not have to wait.

 

[Thirdgen89GTA]

That brings up another extremely valuable point. For those who use manual boxes instead of auto shifters you're waiting on boost to catch up again. Makes life nicer to not have to wait.

It really is a kick in the head when yo do it.

not only are you reducing your shift times by probably .1 seconds or so, you are eliminating the time it takes for the turbo to spool back up to full boost. The ST supports it in the tune by retarding timing during the clutch action.

Thats the biggest advantage to a DSG box or regular automatic on a turbo car. It can keep the throttle blades open during the shift so there is no loss of boost.

 

[Pressure Ratio]

Is some of the the boost falloff while shifting due to torque management? Does the tune change timing, change fueling, throttle blade closure, open the wastegate and so on? In the name of saving the clutch, eliminating tire spin and keep the motor/trans safe by reducing the torque


I would have to think that most new cars are miles ahead of where they were even just 5-10 years ago as far as turbo performance goes. Between more capable ECU's, new strategies in tuning, improvements in manifold & intercooler designs and in the efficiency of turbos themselves.

 

[Eagle]

I'd ask [MENTION=2933]Thirdgen89GTA[/MENTION] what the traction control was set to during that data log, because it looks like you spun for a good amount of 1st, and maybe chirped 2nd, but otherwise had no spin.

Might help answer [MENTION=2612]Pressure Ratio[/MENTION]'s question as well.

 

[Pressure Ratio]

That could be one thing. But even with the traction control off the torque management / "clutch protection" can & will step in. But curious how the ST tune is versus other vehicles that have had torque management improvements with aftermarket tunes.

 

[Eagle]

Oh trust me. Explaining "clutch protection" to people with the GT500 at the half mile was like I was speaking french. Even if they understood the concept they still didn't believe me. They just thought I couldn't drive when other "stock" cars with less tire and suspension could run faster than me.

Ford's clutch management is an interesting beast to conquer.