2-Step Launch Control & WOT Shifting Instructions

[dirtbag]

I don't remember if I shared this with you guys, but here's a draft document on a no lift shift / 2-step box I've been testing with excellent results:

N2MB Racing WOT Box/2-Step Launch Control install instructions on '97 Dodge Viper GTS
http://www.npcompleteperformance.com/wotbox_1000px.jpg/wotbox_1000px-custom;size:220,220.jpg
Main Features:
+ WOT(no lift) Shifting
+ 2-Step Launch Control adjustable to any RPM
+ Rev Limiter adjustable to any RPM (independent of 2-Step limiter)
+ Can adjust WOT shift time & 2-Step without laptop for quick changes.
For more information: http://www.npcompleteperformance.com/

Basically this device temporarily cuts power to the ignition coil packs for a pre-set time during shifting (I use 250ms). Makes it easier and much quicker shifting especially in the viper where 3rd gear can be difficult at times. In fact most of the time I only depress the clutch about 1-2" of travel between shifts. The drivetrain appears to be unloaded and fully synced which allows smoother meshing into the next gear. Shifting in 1/4second seems to be effortless.
http://kriskeller.com/wot/wotcomparison.gif

Tap into the Throttle Position Sensor & Crank Sensor. TPS & CKS sensors feed into connector 3 on the PCM indicated by a black connector. The CKS should be pin 8 and Grey/Black stripe. TPS should be pin 23 Orange/Dark Blue striped wire.
http://kriskeller.com/wot/pcm.jpg

Coil packs are located here, the coil power feed wires (dark green & orange stripe) are located on the passenger side on the back of the motor, one for each of the two coil packs.
http://kriskeller.com/wot/coilfeed0.jpg

Closer look with the wires cut. The red wire on the WOT Box connects to the right most pair wires (coming from under the intake manifold - power feed). The Red/Black stripe wire from the WOT box connects to the left most pair(from the coils).
http://kriskeller.com/wot/coilfeed.jpg

The viper does not have a "clutch up" switch, so I made one with a simple reed switch and earth magnets found at your local radio shack. These switches are often used in home security for door switches. Tap into any key/on power source. In the software enable the option of "reverse clutch" if your reed switch is normally closed.
http://kriskeller.com/wot/clutchswitch.jpg

2-STEP/Launch Control testing
YouTube - N2MB Racing WOT Box/2-Step feature testing on '97 Dodge VIper GTS.

[torquemonster]

interesting. Have you compared track times before and after?

it's a good concept if you are after the best et/lap times

[dirtbag]

Initial testing the WOT/No lift shifting feature shaves the 1/4 mile time down between 250-350ms on average. My biggest jump was from 12.7 down to 12.2 with no vehicle changes(N/A setup at 6,000' density altitude). With larger turbos should be consistently quicker since you maintain boost between gears eliminating turbo lag. There was too much weather and track variables at the last two test-n-tunes to give 100% accurate solid numbers. I'm considering renting the track for a night so I don't have to wait 1.5-2hrs between runs and flip flopping lanes. Since I'm getting less than 4 runs total in a day I'm trying to tune A/F, timing, and methanol injection each run.

I'll keep everyone posted on more results as they flow in. There's another test-n-tune coming up this Friday, hopefully I don't twist another half-shaft on launch again.

On the other hand the additional rev limiter feature useful if you need to drop the vehicle off for service and don't want the "viper tech" road testing above say 3,000 rpms in case his/her foot gets grabbed by those damn under-pedal gnomes. lol.

[bushido]

Thats pretty cool..

Dirtbag how about video of your car punching it?

[99 RT/10]

That is pretty slick. Cost?

[b3rndtt0ast]

if anyone wants one, we are a dealer for them at work. i will get a price for you.
if you want to get ahold of N2MB, check out www.srtforums.com (http://www.srtforums.com) they are pretty big there. they also have one (same box is used) thats a boost per gear boost controller. not sure if it would work on a turbo viper tho.

http://www.npcompleteperformance.com/wotbox for the wotbox and 2 step

[Too Blue]

WOW... That looks pretty cool.

What kind of EMS or computer are you using on your car?

If AEM, doesn't it interfere with the datastream causing problems?
Wonder if it would cause problems with a VEC or SCT?

Any updates?....:eatpop:

[dirtbag]

I'm using the stock PCM. I have MSD boost timing master and splitsec to pull timing back. I think AEM already has these features don't they?

The WOT box just cuts power feed to the ignition coils, not the spark signal. I guess in theory having a VEC or SCT wouldn't make any difference.

It rained at the last test-n-tune, so I wasn't able to get numbers or footage. I'll have to wait until possibly this Friday. Crossing my fingers monsoons don't pop up, and hope a million cars don't show up so I can get more than two runs in.

[Too Blue]

I'm using the stock PCM. I have MSD boost timing master and splitsec to pull timing back. I think AEM already has these features don't they?
I am in the middle of setting the AEM up on a new TT car. The AEM does have three types of TC. Unfortunately I haven't gotten that far...
I would use this set up on my S/C Gen 2.

The WOT box just cuts power feed to the ignition coils, not the spark signal. I guess in theory having a VEC or SCT wouldn't make any difference.
What about the timing advance for different EMS settings. (IE.. with or without Nos, street tune, track tune etc.) I will need to look into that...

It rained at the last test-n-tune, so I wasn't able to get numbers or footage. I'll have to wait until possibly this Friday. Crossing my fingers monsoons don't pop up, and hope a million cars don't show up so I can get more than two runs in.

Good Luck
I, for one, would like to know the results. Curious of your opinion after some more seat time also...

[BOTTLEFED]

very cool!

this is definitely on my want list