launch control with hptunner

[hobbesnmina2001]

Good info, thanks. My launches dont take long and if I warmed up the tires I use second gear above those rpms. Does your temps go up just idling? I would think the exhaust volume is low enough during idle not to be a big factor?

Carlos

[gazgab]

Increase the time do not be idle (Not Enough exhaust flow and spark advance near 0°).
I try to explain the relationship between engine torque and spark advance (I'm French and I do not speak English very well).

[gazgab]

The available torque output of the crankshaft is equal to the torque delivered by the air / fuel mixture minus the friction torque and torque pumping.

The torque delivered by the mixture depends on its quantity (idle vs. full load) and the time when we have the maximum pressure on the piston (for a naturally aspirated pressure up about 13 ° BTDC).
To burn the mixture, an incompressible time is necessary.
at 1200RPM, it must achieve a 0.05 per round (360 ° crank) at 6000rpm while it takes only 0.01s.
Suppose it takes 0.001s to burn the mixture
7.2 ° so you have to burn everything to 1200rpm and 36 ° at 6000rpm
This is why we must put more spark advance at high RPM to low RPM

[gazgab]

This graph shows the evolution of the couple according to the spark advance and the evolution of temps (°Celsius) according spark advance (2450RPM 20% load)

[hobbesnmina2001]

Thanks for the info gazgab, you showed a lot of detail, thanks.
I made the tune for the track only and would flash it at the track, I dont use that feature everyday. In drag racing I have to spend a little time going from the pits to staging lanes, waiting, then clean the tires and make the run. The only time idling and not moving is kept to a minimum since I have the car shut off at the staging lanes unless I have to move up.

Carlos

[Nitroused383]

Wow I just noticed this thread had some replies! Good points gazgab, with the overly retarded timing you are basically turning your exhaust into a flame thrower I'm glad people have found a use for this though.

[hobbesnmina2001]

Does the Lingerfelter unit work strictly on limiting rpm's or a combination with retard?
It just occurred to me that if it was rpm only one could use a tune and just not go to the extreme retard at idle, maybe 12-15 would cut down power along with a good range of rpm's one could adjust the Lingerfelter unit and limited by mph once moving?

Carlos

[gazgab]

They are two ways for limiting rpm:
extreme retard at idle
injection cutoff / cuton (same max rpm)
The torque come back quicker with retard advance and when you cut off/on during a long time, you burn the catalytic converter.
I don't know what method Lingerfelter use. SORRY

[spaz]

tried this today and it is weird. When i go full throttle it doesn't work. it only works when i go half. i set the the tps to 100%

[hobbesnmina2001]

They are two ways for limiting rpm:
extreme retard at idle
injection cutoff / cuton (same max rpm)
The torque come back quicker with retard advance and when you cut off/on during a long time, you burn the catalytic converter.
I don't know what method Lingerfelter use. SORRY

Hi,
I know it's been a while since this post. I recently took the car out of winter storage and I have an idea that may work here.
Gazgab, I was hoping I could get some clarification, you said exhaust temp rose to 1650 within 60 seconds, first you must be measuring exhaust temps correct? Secondly it's not getting that hot from just an idle right?
My thought is if I am just driving easy in the lanes temperature should be extreme yet. I do the burnout in second gear so high temperature rise should only start to actually really begin to rise after the burnout at the line when the rpm's come up before launch and that should not last more then 15-20 seconds max.
My thought is start/use water alky injection to keep exhaust temps under control until the car rolls past the 2 mph speed limit and normal table returns. According to manufacturers water/methanol injection can bring down the temp from 50-100 C.
Since I would most likely be using E85 racing I really do not need the water methanol except for this time or while using a nitrous shot to max out timing.
Has anyone tried this method for water methanol injection?

Thanks

Carlos