Landracing Forum
Tech Information => Technical Discussion => Topic started by: SpeedyPetey660 on February 29, 2024, 12:17:46 PM
-
I changed our air-shifted Jerico to be fired by a solenoid instead of a pneumatic button.
The solenoid will be triggered by ground through a relay.
The reason for the change is that our sponsor (an 80-yr-old rookie in a 230+ mph lakester) is driving the car at Speedweek (209.721 MPH record) and initially wants the car to shift automatically so he has one less thing to worry about as he gets a feel for the car.
Therefore, one trigger will be the 700 MA ground signal from the RacePak data logger RPM output (I'll raise the shift points as the week progresses), and the other will be a manual override trigger on the steering wheel, both through a relay.
I need help with-
1. Wiring the relay to trigger from a ground and send a ground signal.
2. More importantly, in testing the solenoid by simply jumping to the ground on the solenoid, I am getting feedback through the entire wiring system. I know this because the Air/Fuel module reset light blinks when I fire the solenoid. Not a good thing for clean data.
3. I assume this means I need diode(s), but I'm at a loss about where to place them in the system.
I don't know why I'm having so much trouble wrapping my head around this, but dammit Jim, I'm a fabricator/mechanic, not an electrician.
Thanks in advance, Pedro
-
To get the relay to operate you need the ground voltage source to have an amperage output that's high enough to work the relay. Your wrote a 700 MA
ground signal as one trigger. If your trying to light an LED indicator 700 MA should work BUT it seems 700MA is way to low to pick up a relay.
However I question the idea of changing how the Jerico shifts for a single driver no matter the age. A driver should have a feel for every thing involved with driving the car! Any rookie driver driving my car is expected to learn the features of the car we don't reinvent the wheel. Just my thoughts.
Ronnieroadster
-
However I question the idea of changing how the Jerico shifts for a single driver no matter the age. A driver should have a feel for every thing involved with driving the car! Any rookie driver driving my car is expected to learn the features of the car we don't reinvent the wheel. Just my thoughts.
Ronnieroadster
Speaking from experience, switching from an upright roadster or coupe to a special construction car is really intimidating. 550 HP 3" behind your head, laying back in a seat, 7 point belts, your butt 3" from the ground, 1/4 turn lock to lock, thicker fire suit, claustrophobia, a parachute, etc aren't things you can practice for without doing it firsthand.
If the guy writing the checks wants automatic shifting to shorten the learning curve, the guy writing the checks gets automatic shifting.
RacePak Tech assured me that the rpm output will be sufficient to fire the relay.
-
I got my answer. Thank you!
-
"However I question the idea of changing how the Jerico shifts for a single driver no matter the age. A driver should have a feel for every thing involved with driving the car! Any rookie driver driving my car is expected to learn the features of the car we don't reinvent the wheel. Just my thoughts."
Speaking from experience, switching from an upright roadster or coupe to a special construction car is really intimidating, regardless of age or experience. 550 HP 3" behind your head, laying back in a seat, 7 point belts, your butt 3" from the ground, 1/4 turn lock to lock, thicker fire suit, claustrophobia, heat, a parachute, visibility, peripheral vision, feel for tire spin 13' behind you, etc. aren't things you can practice for without doing it firsthand.
If the guy writing the checks wants automatic shifting to shorten the learning curve, the guy writing the checks gets automatic shifting.
I was concerned about the RacePak output as well, but their tech assured me that the 700 mA output will be sufficient to fire the relay.
Thanks, Pete