'89 Daytona C/S NHRA Stocker

[ShelGame]

If a person were so inclined, could a delay box be set up using the cruise switch?

That would be illegal. But possible.

Actually, what I've done is write a bit of code that lights the CE light (in my case, wired to a mini shift light) when the TPS volts is in a specific range. I set it up to light at a setpoint, +/- 0.04v. I currently set it to 1.8v. With the data I have, it seems to be the most stable; without giving up too much response. I'll have to try it and see how the R/T and 60' times are.

I really need a day long TnT this spring. Got too much to try and sort out in typical Friday night 3-run TnT.

[cordes]

I feel like I could do well on a race team looking for good ways to cheat as most of my ideas are illegal. Bummer that the delay box idea is not legal per usual.

[ShelGame]

I feel like I could do well on a race team looking for good ways to cheat as most of my ideas are illegal. Bummer that the delay box idea is not legal per usual.

I'm actually not sure if a delay box would help. They are typically activated after the 60' mark. And my car seems to be very consistent past the 60' mark.

It's getting off the line that needs work.

I've also considered a 'decay' function for the 2-step to work as a kind of traction control. Or, even a slew rate based decay function. But, both of those would technically be illegal, too.

Not sure how they would know or police it.

[cordes]

Technically illegal. Now we're getting somewhere.

[Ondonti]

Technically illegal. Now we're getting somewhere.

All you have to do is push the wrong person's button and even the legal things you are doing could go away.

Rob, do you have a datalog of one of your runs that includes Timing and RPM? I still think you could play with timing where it would only affect 1st gear and that would be legit.
Are you allowed to make changes between rounds ? You could have a few maps and choose the best one based on the track conditions.

[ShelGame]

NHRA has hired an electrical/computer tech guy in most divisions. He's allowed to inspect your wiring and computer, if requested, to ensure compliance. The thing is, if I wanted to hide code in the stock computer, there's very few people out there that could find it. I'm sure the NHRA guy isn't one of them.

But, you're right, if they suspected I was doing illegal stuff with the stock computer, they could just suspend me for a year or something; without really needing to prove it.

On the other hand, if someone protested me; they'd have to put up $750 to do it, and if nothing was found, I get the cash .

[ShelGame]

Here's the data I used to make the conclusion that I'm not so consistent on the throttle pedal:



My TPS volts are anywhere from 1.6 to 2.2 volts. Most of my runs are toward the higher end of that spectrum. I don't have the specific time slips for these runs (that's something I need to make sure I do next year - link my timeslips to my data logs). So, I can't directly compare the R/T and 60' times to these runs. But, my general feeling is that the more I push the pedal, the faster the car gets off the line. But, at the risk of spinning the tires, if even just a little. Spinning = inconsistent. So, I want to avoid that. Of course, always leaving with a different TPSv = inconsistent, too.

The couple of runs I had data for where my TPSv was higher than 2.2, you could see the car was creeping on the brakes (MPH bumped up 1 or 2 mph while staging). I actually have video of the run in particular. It's on my YouTube account as 'Stanton Q2'. And I do have that timeslip - it's one of my best times @ 13.3x. So, maybe the fastest way down the track, isn't the most consistent. Which sucks, because who likes backing off?

As you can see in the chart, launch RPM and MAP are pretty linear with TPSv - which is good. I just need to make a way to always leave with the same throttle position.

So, I wrote the code to light CE light when my TPS volts are 2.0 +/- 0.04 volts (1.96-2.04volts). That should help me launch the car more consistently.

[don miller]

Rob, have you thought of using a 2 step-that would take the tps out of the equation, you would set it for your desired rpm, set the brake, push the gas to the floor and wait for your lite. I would also consider a brake line pressure gauge-find the lowest pressure that holds the car against the converter then always stage at that pressure.
Both of these are common bracket/stock eliminator rwd practises. With the 2 step (some turbo guys would call them an anti-lag) might cause you to modify your boost curve but it should tune up your short times.

[Force Fed Mopar]

Are you not running gear/speed based boost?

[ShelGame]

Are you not running gear/speed based boost?

Speed, yes.

[ShelGame]

Rob, have you thought of using a 2 step-that would take the tps out of the equation, you would set it for your desired rpm, set the brake, push the gas to the floor and wait for your lite. I would also consider a brake line pressure gauge-find the lowest pressure that holds the car against the converter then always stage at that pressure.
Both of these are common bracket/stock eliminator rwd practises. With the 2 step (some turbo guys would call them an anti-lag) might cause you to modify your boost curve but it should tune up your short times.

I've tried a 2 step. It didn't work for me. Even setting it at 2k rpm, it needed too much throttle. Then, when I let off the brake, the boost and rpm shoot up and it spins.

I'll probably try again. I really need a full day TnT to try this stuff out and find a combination that works.

[ShelGame]

When you look at the FWD cars that win bracket races, they're all slow (Angelo, Michael Beard). My guess is, they probably don't have the torque off the line to break the tires loose. If you don't exceed the traction limits, I think a FWD can be very consistent.

So, I need to both improve my traction and limit the torque I put down.

[85boostbox]

Well, you have 3 things going against you right off the bat

1: torquey 2.5
2: way undersized mitsu turbo
3: auto

[ShelGame]

Well, you have 3 things going against you right off the bat

1: torquey 2.5
2: way undersized mitsu turbo
3: auto

Yep, yep, and, yep.

I've been thinking about retarding the cam 2 - 4 degrees to try and move the torque to higher rpm.

And, then maybe some further customized boost control to limit the boost better at low RPM. I currently limit the boost to 7psi (the minimum, since that's where the WG opens). But, if I add a port to the other side of the can, and use the purge solenoid, I should be able to force the can open at any boost, and keep it open until I want it to close. But, that's getting complicated...

[85boostbox]

I wonder if you could integrate a VNT can. Those have two vacuum ports...

[don miller]

I've tried a 2 step. It didn't work for me. Even setting it at 2k rpm, it needed too much throttle. Then, when I let off the brake, the boost and rpm shoot up and it spins.

I'll probably try again. I really need a full day TnT to try this stuff out and find a combination that works.

Most guys would have their left foot on the floor when on the 2 step. Obviously you need to kill a bunch of power at the hit, use a similar launch routine as a small tire nitrous car: just enough wheel speed so you don't bring the motor down then ramp the boost in as the car picks up speed

[Ondonti]

Most guys would have their left foot on the floor when on the 2 step. Obviously you need to kill a bunch of power at the hit, use a similar launch routine as a small tire nitrous car: just enough wheel speed so you don't bring the motor down then ramp the boost in as the car picks up speed

Yeah, if 2000 rpms was too much, do 1750, or 1625 rpms or whatever. All this car does is race so you might as well pull a bunch of timing if the boost is hard to get perfect for traction control. Timing would be more consistent. Get the boost level close to what you need and fine tune it with timing. You can pull enough timing that even "too much boost" won't spin the tires.

[ShelGame]

Most guys would have their left foot on the floor when on the 2 step. Obviously you need to kill a bunch of power at the hit, use a similar launch routine as a small tire nitrous car: just enough wheel speed so you don't bring the motor down then ramp the boost in as the car picks up speed

Yeah, there was no way I could go to the floor even on the 2 step. It starts making boost, and rpms start creeping up, until the brakes can't hold it anymore.

[Force Fed Mopar]

So it's ripping the slicks off on 7psi?!

[ShelGame]

So it's ripping the slicks off on 7psi?!

A couple rotations, yeah. But, it's not blowing them away. The problem is, even a couple rotations means the run is shot. It's got to hook.