Drag Racing Results For My MK5

jetta-girl

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Joined
Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
I just got home from the track. We only got to make one full run, but I'm happy with my results...This is the first race I've competed in with my current set up. 2006 Jetta, 5 speed, DieselPower Digi-PD pro-wired tuning box, and DieselPower TPC module. Here are the results of my one run:
RT .025
60' 2.466
330 6.959
1/8 10.598
MPH 68.16
1000 13.768
1/4 16.429
MPH 85.31

Considering this is my first race since September, I'm hoping to see those numbers get better. I couldn't be happier with how well my car performed!:D
 

woofie2

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Feb 11, 2004
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Republic of Southern Illinois
TDI
Former TDI owner
not bad,
is that with Street tires or Slicks?

my first drag in my stock 2003 Jetta was 17.99 (on 16" street tires aired to 44 psi) someday I will put on my 15" autox tires and go back to the strip.
 

jetta-girl

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Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
That was with street tires on. The track was so slippery that even the 4x4 trucks were losing traction. And, I was driving pretty sloppy.:eek: I hit the rev limiter on my launch, and the car started to de-fuel.

But, overall, I'm still happy with the results!

17.99 isn't bad for stock times! Is your car automatic, or stick? My stock times were in the 19 second range, but I think my car is much heavier than a 2003.:)
 

woofie2

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Location
Republic of Southern Illinois
TDI
Former TDI owner
jetta-girl said:
17.99 isn't bad for stock times! Is your car automatic, or stick? My stock times were in the 19 second range, but I think my car is much heavier than a 2003.:)
sorry it was 17.59 (typo)
stick 5-speed, and I hit fifth on the track, (single pass first ever, so I took off normally not over reving.) oh- and I had all my detailing supplies in the trunk and a case of water(48-20oz bottles)

yes an MKV is much heavier, (400# stock)
 

jetta-girl

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Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
I usually shift around 4500 RPM and don't make it to 5th. When my car started to de-fuel this last time, the RPM's were at 5500:eek: I've learned my lesson, and I'll be paying better attention to my tach at the next race.:eek:

Do you still drag race, or was this just a one time thing for you?
 

beachkokopelli

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Feb 10, 2007
Location
Columbia, MD
TDI
VW 2003 Beetle
Hiya great job on the times. If your running street tyres I guess your running street wheels then? Reason I ask, I am thinking of swapping my 24lb VW OEM 16" alloys for O.Z race 14lb 16" wheels. I have a 2006 overweight by 300 pound jetta, so in the process of putting it on a diet ;)
 

jetta-girl

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Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
Yeah, street tires and the stock wheels. By the next season, I'll be getting drag radials, and aluminum wheels. I'm hoping to get them before this season is over, but I need to stretch my race budget a bit and don't know if I want to yet.
 

SBAtdijetta

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Joined
Apr 19, 2006
Location
Houston, TX
TDI
'10 Jetta Cup 6spd, '02 Jetta Auto
The stock wheels seem not to be too heavy, i just weighed mine tonight, and wheels and tires were 40-42ish, Just put on some used OZ Superturismos GTs but in a 17, a little disapointed they weighed in at 41-43ish lbs. with tires. I guess the difference is the lighter tires on the 16's because of the much smaller width, 195 compared to 225 and the smaller diameter and that must make them light enough to offset the heaver wheel 24lbs stock 16's compared to OZ 17's at 20.7lbs. Oh well they look 100X better.;) Still wish they were lighter... But there is always tracklites in 15's...or 16's.
 

jetta-girl

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Feb 24, 2006
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WA
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06 Jetta TDI
Yeah, I'm going to get the wheels I like best, regardless of weight. Do you think the benefit of extra traction would offset the setback of the extra weight?
 

Spartan1320

Well-known member
Joined
Feb 3, 2006
Location
NJ
TDI
2000 golf Bought in germany
hey guys i got a 2000 4dr golf that im dragging with and my fastest time bone stock is 18. on a .709 light (on a pro tree) does that seem slow for stock


heres the numbers
rt .709
60' 2.538
330' 7.49
1/8 11.708
1/8mph 58.36
1000' 15.305
1/4 18.450
mph 72.90
 
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SBAtdijetta

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Joined
Apr 19, 2006
Location
Houston, TX
TDI
'10 Jetta Cup 6spd, '02 Jetta Auto
jetta-girl said:
Yeah, I'm going to get the wheels I like best, regardless of weight. Do you think the benefit of extra traction would offset the setback of the extra weight?
Seems like an interesting question.. Anyone?

I think that would all depend on the marginal weight gain.. Say just a few pounds, I think that the better tire traction would far offset the small extra unsprung weight, but thats IMHO. But I would not to add much weight, and would be looking to find a lighter wheel if possible.
 

jetta-girl

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Feb 24, 2006
Location
WA
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06 Jetta TDI
I just got back from my 2nd race in Portland, OR. My times weren't much better, again, traction sucked. I was spinning the tires for a good 50 feet. I tried to shifting into 2nd at 3000 RPM's, but that really hurt my 60' times even more. My best time was a 16.55. But, I finished in 3rd place!:D

I definitely need better tires. I can't really lower the pressure anymore on my street tires, that would just cause them to cup and have less contact, so I think I need to learn how to just chill out and launch easy until my tires hook up.:eek:
 

bjmarler

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Joined
Jun 23, 2004
Location
Tullahoma, TN
TDI
Jetta GLS, 2004, White
JettaGirl, what settings do you have your power box and tpc set on for normal driving -vs- racing? I think you said you leave your power box on "f." But I think you set you tpc differently for racing -vs- daily driving???

Also, I have a question about your shift point at 4500 rpm. Have you tried shifting at 4000? What I'm getting at is - when you shift at 4500 does that not put you, after the shift, already past the beginning of the next power curve? In my 04 Jetta I really start to fell a loss of power at around 4000 rpm, so I usually sihift there, and the rpms after I shift are close to the beginning of the next "max torque, power curve, somewhere above 2000 rpm. However, I have had my power box for such a short time that what I just said may be totally wrong now that I have the box! :)

So, I guess my question is, do I have that wrong? lol I don't do any racing like you do, so I really interested in what you have tried and found to work best as far as shift points.

Thanks for the info...
 

Stealth TDI

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Joined
Feb 13, 1998
Location
Newport News, VA
TDI
2017 GTI APR Stage 3 (395 hp/376 lb-ft)
Sarah,

I'll quickly admit you're more seasoned at drag racing than I. I have seven pulls under my belt... all in just one day. But I still wonder what's going on in your first 330-feet. My 1/8 and 1/4 are quicker than yours. But your trap speeds at each point are higher. You're still my drag-race mentor. But I offer you the following mathematical analysis:

......... Me .......... You

RT .... .149 ........ .025 .... <<< You're awesome!
60 .... 2.248 ...... 2.466 ... <<< You're down by 0.218-seconds
330 ... 6.678 ..... 6.959 ... <<< You're down by 0.281-seconds... dropping back...
1/8 .. 10.414 ... 10.598 ... <<< You're down by 0.184-seconds... catching back up...
MPH .. 65.55 ..... 68.16 ... <<< Faster than me...
1000 .. 13.64 .... 13.768 .. <<< You're down by 0.128-seconds... reeling me in...
1/4 .... 16.36 .... 16.429 .. <<< You're down by 0.063-seoonds... almost got me... ;)
MPH ... 82.84 .... 85.31 ... <<< Faster than me...

You told me via e-mail that you tried 25-psi, but opted to leave your tires "as is" at future events since the 25-psi didn't help. My first two runs with AThreeTdi left me in the dust in the first 330-feet because I forgot to reduce my pressures from 35-psi (plus my subpar driving skills). :rolleyes: Once I dropped to 25-psi and improved my shifting, I was right on his mark and eventually edged him out (although I didn't beat him head-to-head).

I have to think your 1-2 and 2-3 shifts are hurting you. I also tend to believe you should shift no later than 4000-rpm. 4500-rpm is too far past your peaks. You might benefit from a visit to the dyno. Have the operator run it right to 4600-RPM. Even if the numbers are not "accurate," they will be accurate with respect to one another and show you when your car is making peak power and torque. Your engine might be falling flat after 4200-RPM... who knows? My car's peak power is around 3500-RPM. Therefore, I try to shift by 4000-rpm to return me to about 3000-RPM in the next gear. You might benefit from a similar driving style (obviously, 3000-rpm was too early).

With your trap speeds, you really should be faster than me (unless your car's extra weight is killing you early). But you'll certainly fix your early times with better rubber. :cool: I may get better rubber someday, too.

Take Care,

Scott
 

Stealth TDI

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Location
Newport News, VA
TDI
2017 GTI APR Stage 3 (395 hp/376 lb-ft)
Spartan,

C&D tested my 98 TDI and ran an 18.6 at 77-mph. I could swear the A4 TDI was similar. Your 18.4 seems consistent with stock times.

Scott
 

jetta-girl

Veteran Member
Joined
Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
Thank you guys for your input. I'm so frustrated with my sloppy shifting. Yes, 4500 RPM is way too late, 4000 would be way better. I need to pay better attention and maybe I'll get it. Last season, I was shifting awesome and turning out some decent runs, but this season, I glance at my tach and have an "oh, sh!t" moment, then shift.:eek: That happens about the 4500 RPM range. I've even hit the rev limiter on accident as soon as I launch.
I'm racing again this Friday the 13th, and my main goal is to try and get my tires to hook up before I stomp on it, and pay better attention to my tach. I find myself looking at my new boost/EGT gauge. Which is totally stupid because it has a high value recall. So, yeah, in a nutshell, I need to get my game back. I'm determined and have my mind set on it.:)

BJMarler, I leave the Digi-PD on "F" all the time. My TPC is set for a sustained PSI of 21~22. Until I figure out how to make my tires handle the power I have, I'm not planning on upping the PSI just yet. I've already used my racing budget for this year, so unless I make more racing money, drag radials and wheels are going to have to wait until next season.:(

Scott, I noticed the same inconsistancies in our respective time slips. The only explanation I have is all the time I'm losing by spinning the tires for such a long time. Does that make any sense?? I'm still using the stock tires which are hard and heavy, I know it's not good, but I'm on a budget. I have better tires in the garage, but haven't had the time to put them on yet. We just moved, so you can imagine how busy that makes me. Maybe I'll try to get the tires swapped out soon and see how much of a difference that makes...

I really appreciate you guys helping me out, and I'll be sure to let you know how I do this Friday. I'm going to try real hard to be shifting closer to 4000RPM.
Sarah
 

Stealth TDI

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Location
Newport News, VA
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2017 GTI APR Stage 3 (395 hp/376 lb-ft)
Sarah,

I just thought of something: The GTechPro has a shift light. I'm not sure if it's annoying enough to get your attention. But you could set it for 3800-rpm. By the time you recognize the light blinking at you eye, you'd actually be shifting at 4000.

Just a thought...

Scott
 

jetta-girl

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Joined
Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
I would love that, but I'm debating on where to put one.:confused: I wish I could just be better disciplined, but maybe it's a better idea to have a machine tell me what to do!;) :D
Thanks for the idea!
 

Jeffmx5

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Joined
Jul 31, 2005
Location
Dunstable, MA, USA
TDI
Golf, 2002, Red / New Beetle, 2000, Red
4K shift point

I don't know if you have access to VAGCOM but it can be very educational if you do. I have done full throttle runs ( to diagnose a bad MAF ) from idle to 5k rpm while logging boost pressure among other things.

At 2K the boost preasure reaches the set point of 1.9 bar (absolute). At 4K the boost starts ramping down from 1.9 bar and at 4.5K the ramp down gets even steeper. I forget how much the drop off is but it is significant. This is for a stock ECU. A chip tune may behave differently. If you search in the performance section you should be able to find torque and HP plots vs rpm. All the stock ones I have seen fall off a cliff at 4K.

Since the boost pressure drops the fueling must drop as well to prevent smoke. Based on this power and torque also drop off strongly after 4k rpm. While the engine can mechanically run to 5.5k rpm I can see no real benefit to rev past 4K.

Shifting at 4K brings the revs down to about 3K in the next gear. Since this is in the heart of the torque and power for the motor it would seem like shifting at 4K should have the best performance.

I am not a drag racer so this is only based on what I have measured and what I have seen posted for the torque and power plots for these motors.

Have fun with the racing! 15 years ago I spent several seasons hammering a Miata around road race courses and had a blast doing it. For road racing driver's skill is the single largest improvement factor. The next one is racing rubber. After a couple of seasons I could "beat" higher performance cars in my bone stock miata because I was a better driver and had track tires on the car.
 

jetta-girl

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Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
Thanks! I've been shifting at 4000RPM as I get on the freeway. Just so I start getting used to how long it takes to get there and how it *feels*. You're right, if I shift right at 4K, the RPM's go down to almost exactly 3K. This feels good, and tomorrow night I'll see if I can do it w/o screwing it all up again. ;)

Wish me luck!! Thanks again for the help!:D

~Sarah
 

OldSchoolFresh

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Sep 20, 2005
Location
Edmonton
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'98 Jetta TDI
The best I've ever done in my MKIII was about low 18s, that's with a bone stock engine, and a few thousand feet above sea level. The 1/4 mile time improved quite a bit after I lowered it, before with the stock suspension I was in the 19s :(

Anyways my absolute best run was:

R/T -.001 <<<<< That's right
60' 2.589
330 7.534
1.8 11.740
MPH 60.54
1000 15.345
1/4 18.426
MPH 73.02
 
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jetta-girl

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WA
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06 Jetta TDI
Awesome RT! That's so close to a perfect light!! Way to go:D
My stock times were mid to high 19's. Now, I'm 16.5 and driving really crappy. I think if I get my shifting and traction down, I should shave off that 1/2 second. At least 0.4 second anyways.

So, let me know if i'm a complete idiot for this line of thought...
Maybe with my new mods, my car is revving up way faster than I'm used to and that's why I can't seem to get into the rythmn of shifting this season? Last year, I was dead on...each pass on the same days were within .01 of each other, but this season, I've been all over the place. Sometimes 2/10's off each pass. I just don't get it.

Oh, and that idiot part, was just for this line of thinking...Not in general.;)
 

Jeffmx5

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Location
Dunstable, MA, USA
TDI
Golf, 2002, Red / New Beetle, 2000, Red
You are not an idiot

It makes some sense. Before the mods I suspect you drove this car a whole bunch and were completely in tune with how it performed. Is this the first car you have raced?

Now you have made some performance changes and the car behaves differently. Much of the car is still the same so your mind is set up for the old characteristics. Practice should improve this.

One other thought. If you have only raced this car you might see if you could practice in several different cars. It would force you to adjust yourself to the different performances of different cars. It might make you more sensitive to how your own car behaves. Good drivers can always get the maximum performance out of any car they drive.

Some related stories from my road course days.

A friend of mine was a very smooth driver and fast when she was alone during practice laps. In a race she was much slower because she was uncomfortable driving in traffic. She took a practice day and had a friend in a higher performance car drive on either side of her all around the track. This forced her to drive off line and still try to be fast. This one practice day dramatically improved her driving in traffic and improved her racing results.

Back in the day there was a road race course at Bridgehampton Long Island NY. It was a long course with many turns and large elevation changes. The most challenging set of turns was at the end of the main straight. They went down hill so you were completely blind as you approached them and there were no visual reference points. If you set up correctly it was possible to stay full throttle from the straight all the way through until the track straightened out and leveled off. The first time you reach the end of the straight at 100mph and you know the road turn right but you can't see the pavement you hit the brakes in a panic of self preservation. Once you get into the corner you realize you can get back on the throttle again. It takes most students all day to get so they don't lift (their foot off the gas). A racing buddy of mine showed up the second day to see the track and see me drive. He asked if he could take a few laps in my car, even though he was not registered for the event. He had never driven my car or seen the track. In 5 laps he got himself up to my best lap time and then he came in.

I guess this is a long way of saying, keep practicing, but don't just practice blindly. Evaluate what you are doing, figure out what you need to improve and then how you are going to improve it. Then practice that part.

From your own admission you are over reving the motor on launch, you are developing too much wheel spin during the first 60', and you are shifting late. Since you added power this all makes sense. Your brain is not going as fast as the car. You need to practice with the new power to get your brain ahead of the car.

There is a saying in roadracing and autocross, to go fast, first you must slow down. It is counterintuitive but true. If you feel like you are hurrying through shifts and scrambling to get on the brakes and turn the car then the car is ahead of your brain and you are slow. If you purposly try to drive more slowly your brain will be ahead of the car and you will be waiting for the right moments to perform your actions. When I have been having problems and then done this my lap times have dropped by seconds so it works.

When you get racing rubber (and that should definitely be the next performance purchase) you will go through this problem again because the car will hook up so much better. The car will again be faster than your brain.

Have a blast! Racing is addictive!

Jeff
 

jetta-girl

Veteran Member
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Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
Thanks, Jeff! I just had my car dynoed today, and I think we've found part of the problem. The boost is spiking right away, and way higher than it was before I had the Turbo Pressure Controller installed. This is causing my car to defuel, and I'm obviously not responding well to that. Next race is this Sunday, April 22nd, so we'll see if I can make any improvements...:rolleyes:

I really appreciate your input, thanks!
~Sarah
 

hdeptech

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Oct 18, 2006
Location
Vancouver WA
TDI
06
dyno helps tune in the car. I feel the 4x4 trucks do have a advantage cause of weight. With the Jetta we need to tune it more like the import guys????? I am onlygiving ideas. A diesel tune is most likely tuned for of the line snap and smoke. with time you will get it. Also is not the fueling of the ECM rated with the throttle response????? Kind of a memory. if the car is driven like a grandma for fuel ecomony the ECM remembers the fuel map and all the makes combustion, once a tune is installed and driven different the ECM takes an amount of time to adjust. Not sure but woundering????
 

jetta-girl

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Feb 24, 2006
Location
WA
TDI
06 Jetta TDI
I think you are right about needing to tune it more like the import guys, but one major obstacle for me is that no one really knows how to tune the MK5's. If I had one model year older, it seems like everything would be golden.
I'm also having to make trips up to BC to get anywhere with the tuning because I can't find anyone around here that knows how to tune diesel cars, just trucks.
Yeah, it seems to take a bit of "breaking in" after any time we make an adjustment, but I really think I might be most of the problem. I'm not really understanding what my car is trying to do, and we are out of synch with eachother. Like jeffmx5 said, it should come back to me with lots of practice. I just need to pay better attention and respond better to what my car is doing.
My dyno graph shows that I'm getting a huge boost spike right off the line. I'm not a mechanic, so sometimes I don't really understand what I'm being told in regards to what my car is doing.:eek: So, I'll let you guys see what the dyno looked like and you can get a better idea of what's happening than if I tried to explain it.
Here is the link to my dyno run:
http://forums.tdiclub.com/showthread.php?p=1689062#post1689062
Mine is the one that says Sarah's MK5. Or something like that.:)
Can you guys tell what's going on?
Thanks again for all the help!
Sarah
 

Jeffmx5

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Joined
Jul 31, 2005
Location
Dunstable, MA, USA
TDI
Golf, 2002, Red / New Beetle, 2000, Red
my best guess

I have never run on a dyno and I have not put power mods on my car so this is my best guess from reading the forums.

The peak that occurs at 2700rpm. My guess is that the power box causes the turbo to develop peak pressure here. The ECU fuels to the pressure and you get your torque and HP spike. The pressure spike is much greater than the desired pressure so the turbo is commanded less boost and then the response is stable from there.

Tuning boxes work by modifying the output of engine sensors so as to fool the ECU into developing more boost and more fueling. IMO this is a kludgy and undesirable technique. A chip tune on the other hand uses the real sensor outputs and "just" changes the desired setpoints or maps.

Many of the systems controlled by the ECU are controlled by closed loop feedback. This is a term used in control loop theory. For example at wide open throttle the stock ECU sets the desired boost pressure to 1.9bar absolute between 2000 and 4000 rpm. If the boost pressure is low then the ECU "tells" the turbo to give more boost (adjusts the VNT) and if the boost is too high, less boost. The ECU measures the boost pressure with the MAP sensor to determine if the boost pressure is correct. This is the feedback part. Because the engine speed and boost pressure are always moving around this system is dynamic. A well designed control loop can adjust the output to the desired value quickly without excessive overshoot or delay.

In order to get more boost the tuning box guys modify the output of the boost sensor to make the ECU think there is less boost than there really is. This affects the gain of the system. The problem is you can't just tell the turbo to deliver more boost all the time or there will be reliability and fuel economy problems a low rpm. So the tuning box has to adjust the "correction" dynamicly with rpm. This adds delay.

Changes in gain and delay reduce control loop stability. There is nothing the tuning box guys can do to correct for this. "I can't defy the laws of physics, captain!" To fix this problem they would need to modify the program in the ECU.

The chip tune guys don't have this problem. When they change the desired set points they can also modify the control loop parameters if necessary to maintain good control loop performance. Properly designed chip tunes should deliver the increased power you want in a nice flat curve just like it came from the factory.

To fix the boost spike talk to the guys that sold/made your tuning box. There may be some adjustments that can be made to reduce the spike. They may also recommend you add a boost control valve. This device is "outside the loop" and limits the maximum boost that the turbo can be commanded to develop. The effect will be to flatten off the spike.

Having smooth consistant power and torque will certainly make your launches more consistant and should make it easier to control your wheel spin.

I hope this helps,

Jeff
 
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