Longacre ACCUTECH DLI User manual

LongacreRacing.com LIT-5241 REV A
Longacre Racing Products
977 Hyrock Blvd.
Boonville, IN 47601
800-423-3110
ACCUTECH DLI TACH
INSTRUCTIONS
On the back of the tach, there are 2 sets of wires coming out, 1 with green, brown, black, & red - see below. There is a
second pair - red and black - in a black casing. These are for the remote Start/Stop switch.
Green wire - to “Tach” output on ignition box or to positive side of coil on non-electronic systems. NEVER connect directly
to high voltage!
Black wire - to ground. Be sure it is connected to a solid ground. Many problems are caused by a poor ground.
Brown wire - Power (connect so it shuts off with ignition off).
Red wire - Power (connect so it has power full time - NOT shut off when ignition is shut off).
Red & Black wires in Black casing for remote Start/Stop switch
These are for the remote Stop/Start switch. Mount where the driver can easily access it. Use a 15/32” or 1/2” drilled hole.
Cut the wire to the length needed. You can use the mini connector included or hardwire the switch directly.
To recall maximum RPM:
Push Recall button on lower left side. The pointer will recall highest RPM & hold that number and will also display on the
LCD to 10 RPM. MAX shows on LCD - lower left corner. Push again to resume normal tach operation.
Note: You can push Recall before going on the track and the tach will constantly display the highest RPM reached to that
point without pushing Recall again. It does not show active RPM once RPM drops below highest point. Push Recall to
resume normal tach operation. This way the driver can see the max RPM without pushing buttons.
To reset - erase max RPM:
Push Reset button and hold 3 seconds to erase old RPM. LCD and pointer go to current reading.
System Requirements:
Tach works ONLY on negative ground systems at a MAXIMUM of 18 volts. Anything over this may damage the tach.
Cars with 16 volt alternators and batteries may need to use a resistor on both red and brown wires.
Remote Stop/Start switch:
This red button switch is used by the driver to start and stop the recording (data logging) process. Mount where the driver
can easily access it.

LongacreRacing.com LIT-5241 REV A
Longacre Racing Products
977 Hyrock Blvd.
Boonville, IN 47601
800-423-3110
ACCUTECH DLI TACH
QUICK START
Record Max RPM & Reset:
To recall MAX RPM push lower Left button. Push again to return
normal tach function.
To reset MAX RPM (erase) push lower Right button and hold for 3
seconds.
Record (Data log) & Replay:
Recording functions are controled by the 2 lower buttons - Left &
Right - and by the remote Start/Stop button (included) mounted
near the driver.
To Record:
Push Right button. - GO - will display on LCD.
Push remote Start/Stop button to begin recording.
Recording elapsed time is shown on top of the LCD.
Push Start/Stop again to stop recording.
To record another session push Start/Stop to get to
- GO - , then again to start another recording session.
Session numbers are shown in the lower left corner of the LCD.
To Replay:
1) Push Right button to - GO -. Push Right button again
to get to Play.
2) Push Left button to select session to replay. Session
number is shown in the lower left comer of the LCD.
3) Push Right button to select playback speed. Options are:
The icon flashes to indicate which is being selected.
4) Push Left button to start actual playback. Push Left
again to stop. While stopped you can use Right button to
change replay speed if you wish or you can back up to play
a section again.
To Replay another session:
Push and hold Right button 3 seconds to exit Play mode, then push
Left to get to - GO-, then again to Play. Use Left button to select the
new session number as above, #1 - 4.
To Erase all recorded sessions:
Push Right button to - GO-. Push the remote Start/Stop button and
hold 3 seconds until Erase appears. Release Start/Stop, then push
and hold it again for 3 seconds. A series of bars appear and
DONE displays. This erases ALL recorded sessions. There is no way
to selectively erase sessions.

LongacreRacing.com LIT-5241 REV A
Longacre Racing Products
977 Hyrock Blvd.
Boonville, IN 47601
800-423-3110
ACCUTECH DLI TACH
SETUP FUNCTIONS
If you are running an 8 cylinder motor and are OK with an 8000 RPM warning light
setting you do not need to go thru the setup process.
All functions are controled by the Recall-Select button (moves to the next mode) on the left and the Reset-Adjust button (adjusts
settings) on the right. This often involves going back and forth between the two but setup is easy and only needs to be done once.
Settings are saved automatically after not pushing either button for 20 seconds. If you want to keep the current setting push Select
(left button) to continue on to the next mode.
There are 2 sets of high RPM warning lights:
On the left side of the tach are 6 LEDs that come on sequentially. These can be used for pit road speed indication at lower RPM or a
sequential shift light at high RPM. You set the highest RPM at which all 6 LEDs are on. They begin to come on - one at a time until
all 6 are on - at 500 RPM below your setpoint, to give you warning. Can be set at any RPM.
On the right side is a larger single Red LED. This is intended to be a high RPM warning light or a shift light. It has 2 settings. At the
first setting the LED comes on steady. At the second setting it flashes rapidly to agressively attract your attention. This can also be
set at any RPM you need.
If you prefer not to use either of these warning light systems set them at a high enough RPM so that they will never come on.
However we strongly urge you to use at least the high RPM warning to help prevent over-reving expensive motors.
THIS TACH AND THE WARNING LIGHTS ARE NOT AN RPM LIMITER.
To get into setup mode hold both buttons for 5 seconds:
Pit Road Speed is the first selection. Each digit is set separately (digits to be set flash). Use Adjust (Right button) to change. When
you have what you want push Select (Left button) to move on to the next digit. Adjust the same way. (Remember that the setpoint
you are establishing is the point where all 6 LEDs are on.) You can set this in l00 RPM increments. Default setting is 9000 so you will
need to reset it if you want to use this feature. If this is all you are setting when you are done simply stop pushing buttons. After 20
seconds the tach will automatically save your changes and revert to normal function. If you wish to change other settings push the
Select (Left button) again and you will go into the next mode - setting the large Red LED.
Set Red LED warning light: After you have finished setting pit road speed above push Select (Left button). The first setting is LED
on steady (default setting 8000). Set as above using Adjust (Right button). When you have the setting you want push Select (left
button) again to move on to the LED flashing setpoint (default setting 8500). Again set as above. If you are done, stop pushing
buttons and the tach will revert to normal function in 20 seconds. If you need to change the number of cylinders push Select (left
button) again.
Set number of cylinders for your motor: This last mode comes after you are done setting the Red LED. The numbers shown
represent the number of times the ignition system fires per revolution. Options are:
0.5 for 1 cylinder
1.0 for 2 cylinder (use this for I cylinder 2 cycle motors)
1.5 for 3 cylinder
2.0 for 4 cylinder (use this for 2 cylinder 2 cycle motors)
2.5 for 5 cylinder
3.0 for 6 cylinder (use this for 3 cylinder 2 cycle motors)
4.0 for 8 cylinder (this is the standard/default setting on new tachs)
5.0 for 10 cylinder
6.0 for 12 cylinder
The backlight on this tach is white and is not adjustable.