Does Supercharging Ruin the Car for the Track?

[AMPowerJ]

Originally Posted by 4sevens.com

Let's meet up at CMP or VIR and I'll let you drive my ess vt2-625 and you can decide for yourself

Well that sounds like an offer I just can't refuse.

[AMPowerJ]

Originally Posted by MaxL

There is a counter point for that. When I drove a lower powered car, all I had to worry about is line and braking, and the rest was not as important. I could floor as soon as the front pointed towards the apex, and had very vague (mostly theoretical) idea about throttle control, throttle steering or brake management. I could also ignore some turns and take them anyway because I did not pick up enough speed since the previous turn to break traction in the next one (e.g., linked turns of increasing radius). With a higher HP lower traction car all that became overwhelmingly important. You can be on the edge of traction more of the time through the track, which makes it more challenging.

Did your arm get tired from all the point-bys?

Just kidding ... sort of.

I do agree that adding more power adds complications and requires more skill and I will admit I am not fully ready for that right now.

[MaxL]

Originally Posted by AMPowerJ

Did your arm get tired from all the point-bys?

Just kidding ... sort of.

I do agree that adding more power adds complications and requires more skill and I will admit I am not fully ready for that right now.

Yeah, I considered wearing driving gloves so that my fingers would not get cold .

But really, if your instructor is saying "now progressively add more throttle" and your foot was on the floor for the last 2 seconds already (not that it made any difference), it's tough to learn about importance of progressive throttle. It's funny now when some people on 328xi say proudly "I do not even need to lift before turn 4" (on Mosport). Well, try that at almost twice the speed...

Keep in mind that the lower-powered car most track junkies here drive are much lighter than street Ms as well, so they can break the rear loose and pick up good speed no problem.

[Gearhead999s]

I have instructed in a couple of supercharged E9x M3's and the power delivery is linear enough that it should not cause any issues for even students of a novice level.Plus it is much easier to respond to point by's

[vantagesc]

Originally Posted by MaxL

There is a counter point for that. When I drove a lower powered car, all I had to worry about is line and braking, and the rest was not as important. I could floor as soon as the front pointed towards the apex, and had very vague (mostly theoretical) idea about throttle control, throttle steering or brake management. I could also ignore some turns and take them anyway because I did not pick up enough speed since the previous turn to break traction in the next one (e.g., linked turns of increasing radius). With a higher HP lower traction car all that became overwhelmingly important. You can be on the edge of traction more of the time through the track, which makes it more challenging.

Fair enough, though I would not consider an E9X M3 the kind of car where you can floor the throttle at the apex. It still oversteers plenty. The caveat being that I have very little driver seat time in the M3.

The extreme example I can think of is an instructor who taught a student with a GTR. First few lessons was with the stock car. The student's race shop convinced him to up power to 6 0r 700hp. When the student came back, he was driving even slower through the turns because of the massive power had him braking too early and in general more overwhelmed as to what was going on. He actually regressed by adding power. Again, this is an extreme example.

I would not fault anyone for falling on either side of this question. Specifically for the M3 though, for the novice driver, I don't think there is harm in holding for for a year or two. Most drivers will never fully maximize the stock car anyway, so to some extent, it IS about fun.

[bigjae1976]

Originally Posted by vantagesc

Fair enough, though I would not consider an E9X M3 the kind of car where you can floor the throttle at the apex. It still oversteers plenty. The caveat being that I have very little driver seat time in the M3.

The extreme example I can think of is an instructor who taught a student with a GTR. First few lessons was with the stock car. The student's race shop convinced him to up power to 6 0r 700hp. When the student came back, he was driving even slower through the turns because of the massive power had him braking too early and in general more overwhelmed as to what was going on. He actually regressed by adding power. Again, this is an extreme example.

I would not fault anyone for falling on either side of this question. Specifically for the M3 though, for the novice driver, I don't think there is harm in holding for for a year or two. Most drivers will never fully maximize the stock car anyway, so to some extent, it IS about fun.

Balance is the key! The right car with the right amount of power with the right suspensions, brakes, and tires.

[GrumpyBimmerFan]

I think that ^ hits it on the head! If you add a supercharger, you need to upgrade the brakes, the tires and suspension. Stock brakes barely handle it as it is, but with added power and weight, you will be carrying more speed, and would need a better set up. Same thing for turns, it would be easier to carry more speed so the suspension is important. Tires, well that's your traction that you would require with added power.
I'm sure if you got a SC and wasn't concerned with tracking, and would just use the car for everyday driving, then you would be fine with brakes, and suspension, but at the track it's important.

[Brian_VACsales]

We had our VF supercharged E92 on the track a lot in the last 1/4 of 2011 and it did really really well. It did not overheat once - just kept making huge power.

As a portly 3800lbs street car on street tires and so-so suspension it did quite well with all out turbocharged <3k lb race cars

photo by J. Owen Photo

[gixxer_kidd]

Originally Posted by Gearhead999s

I have instructed in a couple of supercharged E9x M3's and the power delivery is linear enough that it should not cause any issues for even students of a novice level.Plus it is much easier to respond to point by's

Couldn't agree with you more. I was at the track with PCA at NJMP this past weekend. This was the first time on the track since installing my VT2-600 kit last year. I have to admit, prior to the track I was considering swapping out the pulley to a bigger one to reduce boost at the track but the power is so linear it's just like driving a stock m3 except you have more at your disposal. For a beginner/intermediate driver like myself, I did not feel like the SC was too much. Sure my learning curve might be steeper with the SC but I only plan on tracking my car 3-4 weekends out of the year. For the rest of the time, my car is a daily driver and the extra power makes driving to and from work more enjoyable.

As for the comment with the point by's it's true the extra power does help in passing, but at the same time I didn't abuse it. If I felt someone was driving faster than me in a slower car and was approaching from behind, I would give them an early point by and ease off the throttle a little just so they could make a clean/safe pass. I do track days for fun so I don't let my ego get bruised when a slower car passes me. If anything, it motivates me to be more consistent and smooth with my driving so I can catch up to them again.

One final note, very impressed with the ESS kit. No issues with heat soak or anything. It's been flawless for the past year and flawless on the track.

[Richard@M-World]

I've worked with/coached many track customers with and without superchargers. I've also driven their cars. Here are my 2 cents.

There is no doubt that power is great But, it is useless without control. And for an M3 with a supercharger, the greatest challenge is how you put the power down. On a supercharged car with inadequate tires, the car becomes harder to control coming out of corners. What ends up happening is that the driver would now be afraid to roll onto the throttle (it later becomes a habit), and this habit kills your lap time.

Anyhow, there are many people who compete in time attack, time trials, etc with a supercharger on the M3. So it really depends on how you set up your car as a whole to complement the extra power.

[sleepless]

Since you mentioned street driving, note that the type of supercharged used in all the common kits will not make much of a difference for low end torque. I'm guessing you would still be disappointed.

[Gearhead999s]

Originally Posted by SehrSchnell

False. You step on it and it moves - torque numbers are vastly improved. You're issue will be to hook it...

Geez the ones that I have driven were not very different than my car till they were over 5000 rpm and increades power came on very smoothly.The power delivery felt verry much like the normally aspirated car.I did not feel it had more power where more torque would be welcome like in the 2-4000 rpm range.

[sleepless]

By definition, centrifugal supercharger needs RPMs to make boost, so around town where you spend most of the time in the 2000-3000 range, it will not make enough boost to be very noticeable.

[Gearhead999s]

Originally Posted by SehrSchnell

I'm not hear to argue about that... I was referring to the poster's comment regarding being disappointed with the SC. The power comes sooner than 5000 rpm with the 600 kit - trust me.

Torque is enough for me, I seriously don't know how much more people need. I don't think anybody with these kits will drive around and say "boy, I wish I had more torque".

But than again, I never understood the whole "not enough torque" debate to begin with.

Well they were AA Stage 1 kits so there probally a difference for sure!I sure do not complain about torque with my stock s65 either.You just have to understand where the power is delivered in the powerband.

[sleepless]

Originally Posted by SehrSchnell

It just always blows my mind... the OP ask a question regarding how the SC works on the track, and we end up discussing the low-end torque for the street. Which doesn't f@cking matter at all.

Actually, the OP did mention street driving; that is why I brought it up. Clearly, he wants more power across the RPM range.

[kaiv]

Centrifugal superchargers build boost as the rev climbs. So -assuming a proper tune- the power delivery should be like stock, linear. To give you an idea a 6 psi kit might make 6psi at red line but 0 at idle and 1.5 at 2k rpm.

Disclaimer: these are not exact figures, I'm just illustrating a point. That point being that if you're looking for torque down low those kits won't satisfy you since they do the opposite of that and provide hp high in the rpm band instead.

Only positive displacement blowers (like twin screws) give you a kick down low since they can pretty much make full boost at idle and from them on.

Sadly BMW tuners seem to use exclusively centrifugal blowers. The last company to put a twin screw in a BMW was Eurosport and that was years ago on E36s.

[jvitas]

Originally Posted by kaiv

Centrifugal superchargers build boost as the rev climbs. So -assuming a proper tune- the power delivery should be like stock, linear. To give you an idea a 6 psi kit might make 6psi at red line but 0 at idle and 1.5 at 2k rpm.

Disclaimer: these are not exact figures, I'm just illustrating a point. That point being that if you're looking for torque down low those kits won't satisfy you since they do the opposite of that and provide hp high in the rpm band instead.

Only positive displacement blowers (like twin screws) give you a kick down low since they can pretty much make full boost at idle and from them on.

Sadly BMW tuners seem to use exclusively centrifugal blowers. The last company to put a twin screw in a BMW was Eurosport and that was years ago on E36s.

Twin Screws are not that great. I put a Whipple intercooled on a 2007 Mustang GT. Added 120hp and boosted the torque as well. But the car never seemed that much faster (seat of the pants impression only).

I'm in the process of putting the VF 620 kit on my E92 M3 track car. The added torque is definitely needed. We'll see how well the SC kit works.