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Discussion Starter #1
Hey guys.

I don't know if any of the other guys that had the N2MB02 WOT Box are still here, but I thought I would try to ask to see if I could get lucky.

I'm basically asking those that have one on a manual sky redline what their techniques are for launching at the track.

The first time I went with the WOT Box last year I tried first launching at 3k rpms and dropping it, but I bogged pretty bad. I then upped it to 4k rpms and got a tad bit of spin that I wanted which netted me a 2.1 60'. I did that last year on stock Eagle f1s that had like 60k miles on them. This year I had Hancook low profile tires and I tried to leave at 4K and blew diff up.

I'm wondering if anyone with a 2 step (WOT Box) was leaving from the set RPM and kind of slipping the clutch some? My clutch is a spec stage 3 6 puck with a Spec aluminum flywheel. I'm thinking I could slip it some (not much), but wanted to know what anyone else's technique was like.

Again, this is just for the 2 step. I don't need to know how people with autos launch or how people launch with a manual without a 2 step.
 

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Man...ouch. I do love the thrust you get from a high-RPM launch in general, but I think in the entire time I've owned my car I've maybe tried it once. Usually if I want to get going quickly from a complete stop I'll rev it to about 2K and then quickly release the clutch without dumping it. I don't think that baby little differential with the aluminum casing was made for 4K clutch drops!
 

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Comparable to an uphill-drive-away

There is torque at the wheels before the car is moving.

The clutch is partially released and the torque at the wheels is stopped by the hand brake, so the wheels are not moving. When the hand brake is released there is instant torque available at the wheels.
Sounds expensive.....
 

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Stickshift uphill-drive-away technique is driving basics over here. Without being able to do that you can not even get your license.
I never understood the point of this technique. Why not just learn to release the clutch quickly enough that the car won't roll backwards? It seems trivially easy.
 

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This is what I do. Simply let out slightly on the clutch, just enough to get torque to the wheels, heel-toe a little throttle then let off brake and clutch together and good to go. 0 roll back, and smooth take off.
And this is in Missouri. Its uphill all directions at all times. lol

I understand the handbrake trick, but just haven't ever seen the point in normal driving.
 

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I always thought that above is for older people and not petrol heads :)

I assume most people that can drive stick can do what you described. But it might not be wise in many situations. For instance when one wants to have good control because the car should only move a few feet (like parallel parking on a slope, either forward of reverse, or both several times)

Also when sitting on a slope one has the hand brake engaged anyway, so releasing the hand brake first and then the clutch quickly (to prevent rolling) seems kind of strange.
I still don't get it, it just seems like another thing to have to coordinate and think of. Not to mention that if you buy a recent car many of them now have electronic handbrakes, so this goes out the window. [On the other hand, I suppose they also have that anti-roll-back gadgetry, so...]

The only time I can remember ever having a problem on a slope was in a parking garage in Italy, where you needed to pull up to a machine that was situated on, what seemed like, a 30° slope to put in your ticket. And it wasn't just a slope on pavement, it was on smooth, polished concrete, presumably polished by the spinning tires of everyone trying to get out of there. I put the ticket in, tried to set off, and with a light throttle the wheels just spun and the car slid backwards. Who designed this garage anyway?! Oh right, nobody, we're in southern Italy. :wink: Try again: Let's get out of here the Italian way, give it a good dose of throttle and let off the clutch more abruptly and with some noise and smoke were are out of here!

:cheers:
 

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The old British cars had fly off handbrakes - unless you pushed a button to engage the pawl at the top of the travel, all you had to do was release it smoothly as your clutch bit for a smooth take off even on a fairly steep hill.

Having a handbrake that locks in place the second you hit maximum travel defeats that sort of easy use and you have to have your finger pushing the release button to accomplish a smooth release. Not that big a deal, but I've never quite understood why they wouldn't use the fly off scheme - owners too stupid to engage the handbrake when setting it, perhaps? (I went to test drive a new Fiero but the GM salesman was unable to find, much less release the hand brake....)

BMW uses a residual pressure release in the brake line - when you have been sitting at an uphill light and release your brakes, it holds the rear brakes on for a fraction of a second which is all you need to pull away smoothly. Simple, elegant solution which probably costs a few bucks, which may be the reason that more manufacturers don't use it.

To address the original question, using clutch slip to smooth high rpm take offs is a rather expensive method. That's why some of the car magazines no longer take times from a stop, but use 5 mph as the point where they floor it. If you just have to be a drag racer type (even though mot sports cars are ill suited to that - straight line acceleration isn't their forte), be prepared to pay the overhaul price of a new clutch, possibly with some frequency.
 

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You no longer have to do any of this with a stick. It's called "hill start assist" and almost all vehicles now have this. It holds the rear brakes on your car and when you start to hit the gas pedal, releases them... just wait till you see what's coming for brakes.....

Now back to our regularly scheduled program....:hijack:
 

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Discussion Starter #12
Geez!!!! Ok...I guess the best I've got so far is the handbrake technique. Please guys lets not take this back down the hill roll rabbit hole.

Does anyone have any experience utilizing a 2 step?

So originally I had the 2 step at 3000rpms, but when I would drop the clutch it would just bog almost to the point of a stall. I'm wondering if I lowered the 2 step back down to the 3000 rpms then tried to slip the clutch some on the launch if that would keep the rpms up high enough to eliminate the bog and give me a good enough launch.

It's weird with this setup in that you would think at 3000rpms if it was building boost it wouldn't bog on just letting the clutch out, but for some reason it bogs all the way to 4000 rpms. I've heard this with other vehicles as well....
 

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I'm not sure how much boost you will get under no load my RL doesn't have a boost gauge only the dic but my other cars does have a gauge and under no load boost does not increase much.
 

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Discussion Starter #14
Cop do you have a 2 step? I do and I can build from 5 to 10 psi off the line. I see it every time I run and i have datalogs that show it.
 

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I have to use the handbrake frequently due to our tight street parking. Usually we are parallel parked and get within an inch or two of each other. Just using clutch would ride it and wear over time.

Fwiw, the sky doesnt roll that much either way, at least compared to my delica.
 

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Discussion Starter #16
Ok so, I was emailing with the N2MB WOT Box company and they helped me understand what could be done a little bit working with the system.

So basically, since the 2 step doesn't shut off until the clutch pedal is fully out of it's travel....if i let the clutch out slower it would be even easier on the clutch when I slip it because it would slip with the engine just at 4,000 rpms and not start rising until the clutch is fully out of travel. I think that would be much easier on the drivetrain and clutch to basically let the clutch out slower and let it slip slightly and start to move at 4,000rpms then fully engage while already moving then to just drop the clutch quickly like I was doing and shocking the drivetrain.

Does what I'm saying make sense?
 

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In before the "whats a burnt clutch smell like" and "How do you tell if the rear axles or diff are broken" threads are started.

Manual trans + hard tires + trying to launch = wheel hop

wheel hop = broken parts

You don't need a 2 step unless you get on a slick/soft sidewall tire, smaller diameter wheel, upgrade your clutch, and brace the diff.
 

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Discussion Starter #18
Well...thats not true...i did run it last year and got a 13.6 at 102. I also have a spec stage 3 clutch with lightweight flywheel which I had last year as well...so you can get in before whatever the hell you want!
 

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Well...thats not true...i did run it last year and got a 13.6 at 102. I also have a spec stage 3 clutch with lightweight flywheel which I had last year as well...so you can get in before whatever the hell you want!
Wheel hop can cause significant damage to the drivetrain...but if you're not getting wheel hop then it doesn't matter. Even so, a grippy track and a hard launch will uncover any weak spots you have in the setup. I've seen that first hand. Got a 1.997 60' on a FWD car running crappy Sumitomo tires because the track was so well prepped. I think I saw about 7 cars go home on flatbeds that night from drivetrain failures including my friend's car who broke his torque converter in the same make/model car I had but with a lot less power, a harder shift kit, and far less drivetrain work done to it.
 

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Cop do you have a 2 step? I do and I can build from 5 to 10 psi off the line. I see it every time I run and i have datalogs that show it.
I don't have a 2 step but I'm still not understanding why you would have sustained boost under no load. If on the highway for example you accelerate quickly boost will increase but will drop as soon as you reach your selected speed even if it is at 4k rpm.:willy:
 
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