HEWTECH ELECTRONICS LLC
CDIBOX.COM
VINTAGE SNOWMOBILE CDI BOX's

TEMPORARILY OUT OF STOCK...AVAILABLE LATE 2007

FIREPLUG CDI FOR 75~77 ROTAX RV245/340  
73~75 TNT-F/A & 75 Everest
(not compatible with un-shielded trigger / 1978 or later)



(POLARFIRE / BOSCH REPLACEMENT UNIT SHOWN)
(CLICK TO ENLARGE)

Priced at $165.00 (US funds)    
 Includes 2 New Bosch Coils
Mounts in original factory location with original connectors
(FREE shipping in the US & Canada)

BEST WARRANTY IN THE INDUSTRY!

Uses Factory 3-wire or any standard 2-wire kill-switch!  

  Sled / Engine(s) used for early FIREPLUG Polarfire  R&D  Courtesy of Travis Boesch (MN).

  RV Sled(s) used for recent FIREPLUG evaluation.  Courtesy of Jeff Weber (NY).

We recently received the dyno results for our FIREPLUG / Polarfire replacement.  We are pleased to say our CDI outperformed the factory CDI throughout the RPM range.  We achieved almost an 11% gain in HP near 5000 RPM's and over 5% gain at 8500 RPM's.  The test engine was not stock, however this impressive gain was experienced when only the CDI was changed.   The timing curve is similar to factory at very low & very high RPM, but we were able to tweak it in the mid-range for a stronger pull, which is "Very noticeable!" 

BOSCH / POLARFIRE REPLACEMENT FIREPLUG'S AVAILABLE ONLY FOR 73~77:

TECHNICAL PROBLEMS
 STILL NO-SPARK ?

1. Verify that the chassis to engine (bonding) wire is connected & in good condition.  Without this wire connection, the FIREPLUG CDI will not spark or operate correctly.  

NOTE:  The stock CDI may operate without this bonding wire, since it uses the aluminum case as a common ground.  The FIREPLUG CDI case is isolated and no current passes through it, therefore the wire to connect the Chassis to Engine is necessary.  

1. The Brown wire (our Black wire) from the connector grounds to the engine crankcase.  This wire often times breaks or corrodes over time.  Verify your brown-wire does connect to engine ground coming from your engine, through the harness to the CDI.

2. Disconnect kill-switch harness, often times the kill switch & key-switch fail & short out the CDI box.

Timing Advances too far as RPM's increase or missing at HI-RPM?

1. Verify triggers are metal "shielded type" pre-1978.  (See note below)

1975 245 Engines: 315 ohm Stator & 58-ohm metal shielded triggers. 

1976 250 & 340 (345) Engines: 340~370 ohm Stator, shielded triggers = 55~60 ohms

NOTE:
This CDI is not compatible with 1978 stator / un-shielded trigger combinations.  
If stator is replaced with pre-78 shielded trigger assy, 
CDI will function properly on all later engines.

PAYMENT OPTIONS: See main page at http://www.cdibox.com
Please Verify ALL items & amounts with us by e-mail, prior to purchasing. 

Contact us by E-mail anytime with questions

Phone: (810) 765-0820 (EST) (available most evenings)

This page last updated 08/26/07