Launch by time

This section is dedicated to discussion of DTA engine control units such as the DTA E48 EXP, P8 Pro, DTA S40, S60, S80, and S100, as well as all things ECU related.
rocar
Posts: 107
Joined: Sat Sep 10, 2011 8:20 am

Launch by time

Post by rocar »

Anybody uses launch by time ?
Would like to now if speed sensor works
stevieturbo
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ECU Model: No ECU
Location: Norn Iron

Re: Launch by time

Post by stevieturbo »

I don't think launch vs time needs or uses a speed sensor ?

Launch timer begins when you release the button, and rpm rate climbs against time from button release

I believe Allan used this system for autograss guys where they were not allowed speed sensors etc
rocar
Posts: 107
Joined: Sat Sep 10, 2011 8:20 am

Re: Launch by time

Post by rocar »

But I don't need speed sensor for launch control ,but I need speed to control boost.
So if launch by time is used ,traction control won't work
stevieturbo
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Re: Launch by time

Post by stevieturbo »

Alex could maybe confirm.

But I believe that whilst launch is active, traction control will not work, because launch ramp rate should be controlling traction. Traction control will take over when launch control has finished.

As a separate issue, you could use boost control with a modifier for vehicle speed although not sure how effective that may be during traction control.

As a work around, you could maybe use an additional solenoid valve controlled via an AUX output to try and use that to adjust boost during launch or low speeds ? and maybe use boost control as boost by gear instead ?

Although it sounds complicated.

For drag boost control, lots of guys in the US like the Boost Leash or AMS1000 or AMS2000 type products. Something like that may be worth looking into along with high pressure air control or CO2
Rob Stevens
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ECU Model: S100 Pro
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Re: Launch by time

Post by Rob Stevens »

In the launch menu there is an option to retard before cut to help build boost if that's what you want. If you want to control boost vs speed this is in the turbo menu, you can control from speed (will need at least 1 undriven wheel) or gear (if the ecu knows gear)
Alex DTA
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ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Launch by time

Post by Alex DTA »

The wheel speed sensor will calculate with launch vs time from firmware 79.06, not before.

If launch is active, traction will be off.
Rob Stevens
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Re: Launch by time

Post by Rob Stevens »

Alex, please can you explain how the undriven wheel speed interacts with launch vs time a little more. I can't see anything in the instructions. I've been waiting for launch rpm vs road speed for years and have been turning the pot down manually once moving, could this do the same for me?
rocar
Posts: 107
Joined: Sat Sep 10, 2011 8:20 am

Re: Launch by time

Post by rocar »

My Problem is I want to use Launch by time and undriven speed together .
Rob Stevens
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Joined: Thu Jul 28, 2011 4:10 am
ECU Model: S100 Pro
Distributor: None-Coil On Plug :)

Re: Launch by time

Post by Rob Stevens »

To do what? Does the ECU not display speed when launch by time is used. I'll have to go test!

Is the ecu substituting the undriven wheel speed with the calculated driven wheel speed?
stevieturbo
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Joined: Tue Aug 02, 2011 12:08 pm
ECU Model: No ECU
Location: Norn Iron

Re: Launch by time

Post by stevieturbo »

I think the ecu does do funny things during launch in relation to logged speeds

I know I recall on mine that often only one driven wheelspeed would show at first during launch when clearly both were turning. Looking at some old logs, right driven would drop out during launch, but re-appear after.
Although there's no indication on the log that launch is active, nor when it specifically ends.

But not quite following what you're after here Roger ?

Usually launch vs time is one strategy. And Launch vs speed is another.

As the launch vs speed is gearing based...so it sort of compares driven against undriven...that is almost speed based.

Combining time and speed ? In what way ?
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