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Discussion Starter · #1 ·
Hey Everyone,

When I am at a standstill and I accelerate my car tends to lag before it pulls into a good speed. If I am on the highway and I am already cruising, if I press the gas it pulls well.

Anyone heard of this or experience this before? I want more of the instant pull when I hit the gas instead of it feeling like it struggles before it kicks in.

Thanks!

Aaron
 

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What you describe is normal for turbocharged cars in general, and the S60R specifically. A turbocharged car makes power by using exhaust gases to spin a turbine that forces more air into the intake. That only happens once the turbo is spinning fast enough or "spooled up". At idle there isn't enough exhaust pressure to spool up the turbo, so you don't feel the power until the RPMs rise. On the highway the RPMs are already high enough to spool the turbo so you have power right away.

If you want a car with instant power as soon as you step on the gas from a stop you should sell your car and buy a car with a big V8 engine and no turbo.

Edit: why do I feel like I'm being trolled...
 

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Discussion Starter · #5 ·
What you describe is normal for turbocharged cars in general, and the S60R specifically. A turbocharged car makes power by using exhaust gases to spin a turbine that forces more air into the intake. That only happens once the turbo is spinning fast enough or "spooled up". At idle there isn't enough exhaust pressure to spool up the turbo, so you don't feel the power until the RPMs rise. On the highway the RPMs are already high enough to spool the turbo so you have power right away.

If you want a car with instant power as soon as you step on the gas from a stop you should sell your car and buy a car with a big V8 engine and no turbo.

Edit: why do I feel like I'm being trolled...
This makes sense, thanks for the explanation. Why do I feel like it is worse than it once was though? Could I be losing boost pressure or something like that? Any threads available that show all of the lines to check?

Thanks,
 

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This makes sense, thanks for the explanation. Why do I feel like it is worse than it once was though? Could I be losing boost pressure or something like that? Any threads available that show all of the lines to check?

Thanks,
You should definitely buy a boost gauge. This is exactly why.
 

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On a healthy R, if you are above 2K RPM the turbo should be able to start building noticible boost within a second or two of hitting the throttle.

If not you need to do a stage 0 on your car to make sure all is well, and if the turbo still takes too long to build up boost its a good sign your turbo is in its final days.
 

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Can you left foot on the brake and floor the accelerator from a standstill to get the revs up to launch in the automatic? Bit like launch control on top end cars.
 

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Can you left foot on the brake and floor the accelerator from a standstill to get the revs up to launch in the automatic? Bit like launch control on top end cars.
Full disclosure: I do not have an automatic R, and I am not an expert on turbos. I am however very mechanically inclined and went to engineering school.

I would not do that.
 

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Can you left foot on the brake and floor the accelerator from a standstill to get the revs up to launch in the automatic? Bit like launch control on top end cars.
Full disclosure: I do not have an automatic R, and I am not an expert on turbos. I am however very mechanically inclined and went to engineering school.

I would not do that.
I haven't heard good things about "brake boosting" either. Did a Google search and this is the most technical/knowledgeable answer I can find:

"Here are some basics you need to understand about how the torque converter and transmission work wrt "brake" torque for launch.

Torque converter is basically two sets of finned fans spinning opposite each other in a high-viscosity liquid filled chamber. As one fan spins, it forces the liquid (ATF) to spin up therefore transferring that motion to the 2nd set of fans. This is the most basic explanation of how a torque converter works. It converts the torque from the engine into heat while the transmission remain static.

Where that comes into problem when standing on the brakes, is all that energy the engine is making has to transfer or convert into heat, period. There's no where else for all the torque and horsepower to go except get converted into heat by the torque converter. Heat is the ultimate enemy of any lubricant, for every 20 degrees above 210 degrees Fahrenheit it basically HALVES the life and the effectiveness of the lubricant. As the lubricant (ATF) heats up pas a certain point it starts to break down. Since the typical BMW automatic transmission is SEALED and not serviced at a regular interval, the broken down fluid from each brake stand has no where to go except to stay in the system and gunk-up the various passages of the internals of an automatic transmission.

I don't know how many of you have seen the internal workings of a BMW automatic transmission, do a "google" search for "valve body" and see how complicated the internal fluid passages are. It's a series of mazes and valves and passages that controls when one actuator moves one gear and disengages another. The passages are TINY. The valves are TINY. Once gunked up enough to stop flowing, various components break down rapidly in an automatic transmission. Not the most pretty sight, especially given the "lifetime" fill nature of BMW autos.

If you're still reading past all that mumble-jumble, here's the ramifications to brake torquing for launch. Is it bad for your torque converter and automatic transmission? Yes. Will it destroy your torque converter and automatic transmission to do it once in a while? Not likely. Should I do it when I stop-light race or at the drag strip? Not that I condone street racing, and I think people who need to prove they're faster on the street has something small they're compensating for, but if you want to beat the guy next to you at the drag strip or achieve a respectable time, you absolutely need to brake torque...However, just be aware that every time you do it, you're not doing your fluid any favors since all that energy generated by the engine is converted directly into heat that destroys your ATF, same ATF that's shared between the torque converter and transmission. I wouldn't brake torque regularly unless I can change my automatic transmission fluid on a regular basis."

On the R's I saw a video on a Facebook page recently that showed the engine cut off when the driver did a brake boost from a stand still for more than five seconds. I'm sure Volvo programmed that into the car for a reason...
 

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Full disclosure: I do not have an automatic R, and I am not an expert on turbos. I am however very mechanically inclined and went to engineering school.

I would not do that.
I haven't heard good things about "brake boosting" either. Did a Google search and this is the most technical/knowledgeable answer I can find:

"Here are some basics you need to understand about how the torque converter and transmission work wrt "brake" torque for launch.

Torque converter is basically two sets of finned fans spinning opposite each other in a high-viscosity liquid filled chamber. As one fan spins, it forces the liquid (ATF) to spin up therefore transferring that motion to the 2nd set of fans. This is the most basic explanation of how a torque converter works. It converts the torque from the engine into heat while the transmission remain static.

Where that comes into problem when standing on the brakes, is all that energy the engine is making has to transfer or convert into heat, period. There's no where else for all the torque and horsepower to go except get converted into heat by the torque converter. Heat is the ultimate enemy of any lubricant, for every 20 degrees above 210 degrees Fahrenheit it basically HALVES the life and the effectiveness of the lubricant. As the lubricant (ATF) heats up pas a certain point it starts to break down. Since the typical BMW automatic transmission is SEALED and not serviced at a regular interval, the broken down fluid from each brake stand has no where to go except to stay in the system and gunk-up the various passages of the internals of an automatic transmission.

I don't know how many of you have seen the internal workings of a BMW automatic transmission, do a "google" search for "valve body" and see how complicated the internal fluid passages are. It's a series of mazes and valves and passages that controls when one actuator moves one gear and disengages another. The passages are TINY. The valves are TINY. Once gunked up enough to stop flowing, various components break down rapidly in an automatic transmission. Not the most pretty sight, especially given the "lifetime" fill nature of BMW autos.

If you're still reading past all that mumble-jumble, here's the ramifications to brake torquing for launch. Is it bad for your torque converter and automatic transmission? Yes. Will it destroy your torque converter and automatic transmission to do it once in a while? Not likely. Should I do it when I stop-light race or at the drag strip? Not that I condone street racing, and I think people who need to prove they're faster on the street has something small they're compensating for, but if you want to beat the guy next to you at the drag strip or achieve a respectable time, you absolutely need to brake torque...However, just be aware that every time you do it, you're not doing your fluid any favors since all that energy generated by the engine is converted directly into heat that destroys your ATF, same ATF that's shared between the torque converter and transmission. I wouldn't brake torque regularly unless I can change my automatic transmission fluid on a regular basis."

On the R's I saw a video on a Facebook page recently that showed the engine cut off when the driver did a brake boost from a stand still for more than five seconds. I'm sure Volvo programmed that into the car for a reason...
As some one who owns a GT 06 R with the auto trans, brake torking or brake boosting its self is not doing any major damage to your auto trans by its self.

Now if you are not smart enough to change the trans fluid depending on how much you abuse the car, then yes burnt trans fluid will eventually harm the trans if you leave it long enough. Lots of heat will break down the fluid in no time.

What brake torquing does do is generate a tremendous amount of heat in the trans fluid, and if you do a bunch of brake torquing then you probably need a good external trans cooler. I for sure wouldn't do back to back to back launches on with only the factory trans cooler.

I will bet over my life time, I have done more than a thousand brake boost launches in various auto trans cars, most of which were turbo charged and AWD and not a single trans problem from one of them. 3 AWD DSM's, GMC Typhoon, Audi A6 2.7t, V70R, ect.

If you have a bone stock GT there can be a hint of turbo lag from a dead stop if you roll into it with out launching the car.
 

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I had an 04 gt. I break torqued and launched the car and sheared the collar sleeve. So even after all the good info from stealthy I'm just adding another reason not to do so. I have never launched my m66 R and don't plan on doing so.

From my electronic gismo- Galaxy S6
 

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My opinion for what it's worth, if it's not done often and you aren't stupid about it, it's not a concern. By not stupid I mean if you understand the mechanics of what it does (stated in previous posts) it would be obvious not to do it for an extended period of time as that just really gets the fluid hot. I've been next to people that will sit at a red light and just hold on the brake an accelerator without even looking at adjacent lights to know when theirs will turn green. 5-10-15-20 seconds go by and they are still standing on both pedals.

I have not performed brake boosting from a rolling start. Anyone try that guy on an automatic car? Even a manual for that fact?
 

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Full disclosure: I do not have an automatic R, and I am not an expert on turbos. I am however very mechanically inclined and went to engineering school.

I would not do that.
Everything he said.
 

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Here is a thought for all the scaredy cats here. The torque converter isn't going to generate any more heat while power breaking than it does while you accelerate away from a light from full throttle.

Another thought, the power train is designed to handle ALL the torque the engine can throw at it or it would never last close to a couple hundred thousand miles.

All forces in good moderation of course, but some of you phobic types need to stop acting like the R is made of glass just because its possible for parts to break every now and then.
 

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+1 Never gonna a be the best drag racer. And even so we fear for our angle gears.

What you describe is normal for turbocharged cars in general, and the S60R specifically. A turbocharged car makes power by using exhaust gases to spin a turbine that forces more air into the intake. That only happens once the turbo is spinning fast enough or "spooled up". At idle there isn't enough exhaust pressure to spool up the turbo, so you don't feel the power until the RPMs rise. On the highway the RPMs are already high enough to spool the turbo so you have power right away.

If you want a car with instant power as soon as you step on the gas from a stop you should sell your car and buy a car with a big V8 engine and no turbo.

Edit: why do I feel like I'm being trolled...
 

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Or think of it this way, if you ever use your R to help pull a buddy out of a ditch you betcha you are stalling the torque converter. Or another example, snowed in trying to get moving but the tires are frozen to the ground, stalling the torque converter. Everything in moderation. Best thing you can do for yourself is not believe Volvo's lifetime fluid claims and change your transmission fluid on reasonable intervals :D
 

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As some one who owns a GT 06 R with the auto trans, brake torking or brake boosting its self is not doing any major damage to your auto trans by its self.

Now if you are not smart enough to change the trans fluid depending on how much you abuse the car, then yes burnt trans fluid will eventually harm the trans if you leave it long enough. Lots of heat will break down the fluid in no time.

What brake torquing does do is generate a tremendous amount of heat in the trans fluid, and if you do a bunch of brake torquing then you probably need a good external trans cooler. I for sure wouldn't do back to back to back launches on with only the factory trans cooler.

I will bet over my life time, I have done more than a thousand brake boost launches in various auto trans cars, most of which were turbo charged and AWD and not a single trans problem from one of them. 3 AWD DSM's, GMC Typhoon, Audi A6 2.7t, V70R, ect.

If you have a bone stock GT there can be a hint of turbo lag from a dead stop if you roll into it with out launching the car.
An interesting not is before my GT transmission upgrade I could get the RPM's up to almost 4k. I always did a trans flush after each race which was about 7 to 10 runs down the airstrip. I also have a trans cooler to reduce the heat build up. The Gt has some serous heat issues above 150mph.

With the rebuilt Valve Body I can not get it above 2500 rpm on a brake launch and we are building the car accordingly. The shift are nice but still not bad off the line.

IMHO flush when you push it
 

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Also if you're in Flagstaff as your little location text says under your username, you're at 7,000 feet elevation which will add a ton of turbo lag. You're operating with 77% of the air pressure (and therefore oxygen) of sea level. You're basically starting at -3.3 lb of boost, the turbo has to spool extra to make that up.
 
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