thorpep Posted July 1, 2002 Share Posted July 1, 2002 I have a friend who has some fancy (expensive!) computer tuning equipment. To tune my 1997 standard HPC on carbs he needs to know the Ignition timing, can someone help please? Link to comment Share on other sites More sharing options...
EFA Posted July 1, 2002 Share Posted July 1, 2002 Your car does not have adjustable timing. It derives a timing signal from a 58 tooth wheel on the crank inside the engien which is picked up by the sensor 6" below the number 2 exhaust header. All timing etc is fixed and cannot be changed unless you remap with a new programambel ECU. To tune, you can only adjust the choke sizes, main jets, emulsion tubes and idle mix, all of which is carb based tuning, and relaly needs a rolling road (except idle mix) to get any appreciable gain/improvement) If your tuning expert did not realise this, he might be a bit dangerous! Fat Arn Visit the K2 RUM siteid=red> See the Lotus Seven Club 4 Counties Area Website hereid=green> Link to comment Share on other sites More sharing options...
EFA Posted July 1, 2002 Share Posted July 1, 2002 BTW. People with vast ranges of expensive tools are normally dangerous. Look at the Count for ex! Fat Arn Visit the K2 RUM siteid=red> See the Lotus Seven Club 4 Counties Area Website hereid=green> Link to comment Share on other sites More sharing options...
thorpep Posted July 2, 2002 Author Share Posted July 2, 2002 Arnie, Thanks for your quick reply. Iunderstand that the timing is not adjustable but can someone tell me what it is? Link to comment Share on other sites More sharing options...
stevefoster Posted July 2, 2002 Share Posted July 2, 2002 Arnie said it. Choke size, jets, carb balance and idle screws. If it was running ok before and nothing is worn out or broken and it's just running rough then the idle screw's and balance is all. For idle jets, if you are using the original Caterham jetting with 40mm chokes on DCOE 45's I find about 3 turns up from shut is about right. It can vary from choke to choke and of course engine to engine. Start with 2.5 and work by 1/4 turn until you get the best running. (Be carefull not to overtighten these shut as you damage the seats) Then balance either using a tube to listen to suck to get it equal or a carb balancer like Webcon Sychronisatur (or similar foriegn speak). You don't need gas sniffer gear to get this right. Rejetting for more power or driveablilty is a qualified job and really needs sniffer equip for it to be time effective at a manhour price. Steve My racing pics hereid=red> Hants (North) and Berkshire area club site hereid=red> Edited by - stevefoster on 2 Jul 2002 13:56:52 Link to comment Share on other sites More sharing options...
EFA Posted July 3, 2002 Share Posted July 3, 2002 I have no idea what the timing values in this ECU would be. Only way to find out is to call Caterham or MBE Fat Arn Visit the K2 RUM siteid=red> See the Lotus Seven Club 4 Counties Area Website hereid=green> Link to comment Share on other sites More sharing options...
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