TC88A Plug-In Ignition with Versions for all 2003-2006 Carbureted Twin-Cam 88 and Sportster Models with Single 12 Pin Connector and 2004-2007 American IronHorse

Wide timing advance adjustment range accommodates stock to highly modified engines

Digitally set RPM limit (100 RPM steps from 3,000 to 9,900 RPM)

Full support for J1850 data bus used for communications with instrument cluster and turn signal/security module (TSM/TSSM)

Compatible with aftermarket tachometers

Built-in data logging. Stores last 30 minutes of engine operation

Extensive diagnostics

Optional USB interface and software for custom programming and data analysis. 

Billet aluminum housing with black anodized finish

Easy plug-in installation

View the TC88A Installation Video


Visit our Tech FAQ for more detailed information about using our ignition systems in performance applications!



New USB Interface

Part Number 18014

Interfaces all Daytona Twin Tec engine controls (ignition and fuel injection systems) to USB port on laptop PC

Includes all required adapters for Models 1005-1007, TC88, and TC88A ignitions, and TCFI/VRFI fuel injection systems


High Output Coil for Twin- Cam 88

Part Number 2008

Fits most 1999 and later carbureted models - same size as stock coil P/N 31655-99 (will not fit in place of P/N 31639-99) 

Greater than 50 mJ and 40,000V output for demanding performance applications

Compare to Screamin' Eagle coil P/N 31704-99 - same size and electrical specs at a substantially lower price!


Universal Spark Plug Wire Set

Part Number 3002

Universal set for all Twin-Cam 88  applications with 90 spark plug boots and straight coil boots 

7.0 mm black silicone insulation with ultra low resistance 500 ohm/ft spiral core correctly fits special Twin-Cam 88 coil terminals (most competitors force fit incorrect 8.0 mm wire - we use the right wire size) 


Order online using Paypal or call us at 386-304-0700  (Monday-Friday 9 AM to 5 PM Eastern time) for credit card and COD orders. For online orders, please email any special instructions to 


All products covered by our 1 year limited warranty.


Special note to domestic Sportster and all Japanese customers: domestic Sportsters and all H-D models exported to Japan require a different speedometer calibration factor programmed into the ignition module. Please specify your model and we will program your unit with the required calibration factor at no charge. 


Part Number Description Suggested Retail
1009-EX TC88A EX Plug-in Ignition  (with ARB E.O. No. D-641-1 for 2004-2006 carbureted Twin-Cam 88 $341.00

1009 TC88A Race Plug-in Ignition  (for 2003-2006 carbureted Twin-Cam 88 and Sportster with new 12 pin ignition module). Note for Sportster customers: TC88A units for Sportster applications require special calibration for correct speedometer readings. Please indicate the year and model of your Sportster when ordering. Not legal for sale or use in California or on any pollution controlled vehicles. $341.00

1009-IH TC88A-IH Plug-in Ignition Kit (for 2004-2007 American IronHorse motorcycles). Not legal for sale or use in California or on any pollution controlled vehicles. $370.00

18014 USB Interface (provides USB connectivity for all Twin Tec engine controls. Includes 6 foot USB cable and Windows XP/Vista/7/8/10 drivers on CDROM). Not legal for sale or use in California or on any pollution controlled vehicles. $94.00


18006 TC88A Power Adapter (12 volt power supply for bench top programming. 110-240 VAC multi-plug international compatibility) $114.00

2008 High Output Coil  (for most 1999 and later carbureted Twin-Cam 88 applications) $107.00

3002 Universal Spark Plug Wire Set  (7.0 mm black silicone with 500 ohm/ft spiral core. For Twin-Cam 88 applications with 90 spark plug boots and straight coil boots) $24.00


Super Deal!

TC88A EX Ignition Kit (includes TC88A EX ignition, USB interface, P/N 2008 coil, and P/N 3002 wire set. With ARB E.O. No. D-641-1 for 2004-2006 carbureted Twin-Cam 88)  $515.00


Eclipse CP-463 Deutsch Terminal Crimping Tool (for TC88A-IH installation) $45.00



The TC88A provides coverage for all 2003 and later H-D carbureted models using the new 12 pin ignition module. The 50 states street legal TC88A EX version fits  2004-2006 carbureted Twin Cam 88 engines and features advance curves suitable for all street applications including high compression engines. The TC88A Race version fits all 2004-2006 carbureted Twin Cam 88 and 2003-2006 Sportster engines and includes race advance curves with a slightly wider adjustment range. Note for Sportster customers: all TC88A units for Sportster applications require special calibration for correct speedometer readings. Please indicate the year and model of your Sportster when ordering. The TC88A is constructed with a low profile machined billet aluminum housing. The unit offers easy plug-in installation and all the switches are accessible from the top - a significant advantage for most installations. 

Four rotary switches are used to set the advance characteristics and RPM limit. Since the new engines use a non-adjustable crankshaft position sensor, mechanical timing adjustments are no longer possible. The TC88A solves this problem with a switch for setting the initial timing. A second switch sets the slope of the advance curve. The combination of these two switches allows the user to optimize the timing advance for a wide range of applications - from stock to highly modified engines. 

New H-D motorcycles use the SAE J1850 data bus for communications between the ignition module, instrument cluster, and turn signal/security module (TSM/TSSM). The TC88A fully supports this new J1850 data bus. 

The TC88A features built-in data logging that stores data for the last 30 minutes of engine operation including RPM, vehicle speed, manifold pressure, ignition advance, and battery voltage. Engine builders will find the data logging feature highly useful for tuning, diagnosing problems, and reducing unjustified warranty claims. 

An optional USB interface and Windows compatible software allow the use of a laptop PC to program a custom advance curve for precise dyno tuning, download data logged by the unit, and access additional features such as speedometer/odometer recalibration (to accommodate tire and gear changes). The USB interface plugs into the existing H-D diagnostic connector on the motorcycle wiring harness. The USB interface is sold separately, but Windows compatible software is available for download. The software will operate in demo mode without an ignition attached. 

Like the H-D OE module, the TC88A sends RPM data to the OE tachometer over the J1850 data bus. TC88A units also provide an optional 12 volt square wave tach signal (one pulse per revolution) that is compatible with most tachometers intended for 1999-2003 Twin Cam 88 applications. This allows you to retrofit a wide range of tachometers to newer 2004-2006 models. Please download the TC88A installation instructions for details on tach hookup. If you plan to use the optional tach hookup, you will require the USB interface and software to enable the tach output.

TC88A-IH - Special Version for 2004-2007 American IronHorse Motorcycles 

American IronHorse motorcycles use a non-adjustable ignition system manufactured in England by Gill. The TC88A-IH is a special version of our TC88A ignition that is compatible with 2004-2007 American IronHorse models. Installation involves cutting off the original equipment 18 terminal AMP connector used with the Gill module and replacing it with a 12 terminal Deustch connector supplied with the TC88A-IH kit. On 2005 and later models, some minor rewiring of the MAP sensor and engine temperature sensor ground connections is required. Please refer to the TC88A-IH Installation Instructions for details.


Download TC88A Installation Instructions 


Top Fuel Harley racer Wayne Pollack looks confident and relaxed as he gets ready to test his Project 200 bike (200 MPH street legal). To put this into perspective, consider that the takeoff speed on the Boeing 747 seen in the background is only 180 MPH.  The engine is a modified Jims 120 CID Twin Cam that runs on pump gas with additional power produced by a methanol/nitrous oxide system. The TC88A is used as the engine control module and drives a Crane HI-6DI2 two channel CD ignition. The sharp jump on the dyno chart occurs when the methanol/nitrous system kicks in to produce over 238 HP.     



PC Link TC88 Software for Programming Custom Advance Curves

PC Link TC88 software runs under Microsoft Windows XP/Vista/7/8/10. We no longer support older Windows versions. PC Link TC88 allows the user to program Twin Tec TC88 and TC88A ignitions with custom advance tables and other engine parameters. An optional USB Interface (P/N USB-INTF) is required for on-bike programming. Bench top programming also requires a power adapter (P/N TC88A-ADAPT). Advance table data can be edited by clicking on and dragging individual points on the 3D chart display or you can directly enter numeric data on the spreadsheet grid. The advance table consists of 16 columns for RPM and 8 rows for manifold pressure.


In addition to editing the advance table, you can also use PC Link to edit certain engine control parameters stored in the ignition module. You can set the number of cranking revolutions before the engine fires. An engine builder can program Twin Tec units with a custom advance curve and then add a fixed RPM limit and/or fixed initial timing. With race versions, you can offset the rear cylinder timing for maximum power during dyno tuning.

On 2003 and later models using the new J1850 data bus, the ignition module converts signal pulses from the VSS (vehicle speed sensor) to data that is transmitted to the instrument cluster. Scaling (in terms of VSS frequency/speed) varies slightly between models depending on tire size and gear ratio. You can use PC Link TC88 software to change the default scaling and recalibrate the speedometer/odometer. Refer to the PC Link TC88 documentation for details.


Minimum PC requirement is a 300 MHz Pentium with super VGA display (SVGA with 1024 x 768 pixel resolution). The PC must have a free USB port.  For more details, please refer to our PC Link Tech FAQ.

PC Link TC88 software is free! You can always download the latest version of the software and instruction sheet from our website. The software will run in demo mode without an ignition attached. For your convenience, we include a copy on CDROM when you purchase the optional USB interface. 

Download PC Link TC88 Software and Instructions 


TC88A Data Logging Software

The TC88A features built-in data logging. During dyno testing, you can display real time engine data on an instrument panel type screen. The TC88A also stores data for the last 30 minutes of operation. You can download and display this data on a chart recorder type screen. Available data includes RPM, vehicle speed, manifold pressure, ignition advance, and battery voltage. The TC88A data logging capability greatly facilitates fine tuning and diagnosis of driveability issues. The data logging software, TC88A Log, has the same PC requirements as described above for  the PC Link TC88 software. For more detailed information, we suggest that you download the TC88A Log software and instructions. The software download includes a sample file with actual data.  

Real Time Engine Data Display


Data Logging Chart Display


The data logging software also allows you to download operating statistics and historical diagnostic codes.  Downloaded operating statistics are displayed as shown below. Total hours represents the total time that the engine was running. ID represents the firmware identification. This field typically includes the manufacturer (Twin Tec), model number, program revision and author's initials, and date. Elapsed time is displayed for 13 RPM bands from idle to 6999 RPM. The utility also displays the maximum engine RPM, time at the RPM limit (in seconds for better resolution) and the number of engine starts. All this data can be printed to provide a permanent record. The data stored in the module for maximum engine RPM and time at the RPM limit  can be cleared. All other elapsed time and engine starts data is permanent. 

Any historical diagnostic codes logged by the TC88A are listed along with the number of trips (engine start cycles) since the individual code was last logged. The software can also clear diagnostic codes. 


Operating Statistics Data


The elapsed time data in the various RPM bands can be displayed in the form of a histogram chart by clicking on the Histogram button. Clicking on this button causes the chart shown below  to appear. Color coding of the bars helps to interpret the data. The idle RPM band is blue, normal operating RPM bands are green and high RPM bands are yellow and red. The chart is automatically scaled for best display.  

Operating Statistics Histogram Chart


TC88A Log software is free! You can always download the latest version of the software and instruction sheet from our website. The software will run in demo mode without an ignition attached.  

Download TC88A Log Software and Instructions