Quick question...timing S3 N/A

[CAM79]

Hi,

At last a recon water pump is on, and a new cambelt for good measure I not looking forward to the next water pump change!

As I haven't had the car that long I going to set the car up as it should be, especially now that I'm in the middle of these jobs.

The S3 service manual states that there are different 'Static Ignition Timing BTDC' values. The car is an '83 'Esprit 3', and looks like it's got electronic ignition, what it the correct BTDC value? I'm guessing it should be 8 degrees or 10 degrees?

Thanks in advance!

[lotusguy]

CAM79 said:

Hi, At last a recon water pump is on, and a new cambelt for good measure I not looking forward to the next water pump change! As I haven't had the car that long I going to set the car up as it should be, especially now that I'm in the middle of these jobs. The S3 service manual states that there are different 'Static Ignition Timing BTDC' values. The car is an '83 'Esprit 3', and looks like it's got electronic ignition, what it the correct BTDC value? I'm guessing it should be 8 degrees or 10 degrees? Thanks in advance!

Cam79,

The different specs are relative to the market the car was originally manufactured for.

Assuming you are in the USA w/ a USA Market car, your car is spec 10. This means that you have a Lucas Constant Energy Ignition 45D Distributor (electronic, w/o points).

The static timing spec for this car is 10°BTDC @ 950RPM ± 50RPM. Because you have a centrifugal advance of 16°, your total advance would be 26°BTDC @ 3,000RPM.

Because the 907/910 engine likes advance up to 32°BTDC, you could advance the static timing to as much as 16°BTDC, although I suspect that this would be too high, but anywhere between 10° & 14°BTDC would be good. I would split the difference and go for 12° and see how you like it. Happy Motoring! ...Jim'85TE

[B16 RFF]

lotusguy said:

CAM79 said: Hi, At last a recon water pump is on, and a new cambelt for good measure I not looking forward to the next water pump change! As I haven't had the car that long I going to set the car up as it should be, especially now that I'm in the middle of these jobs. The S3 service manual states that there are different 'Static Ignition Timing BTDC' values. The car is an '83 'Esprit 3', and looks like it's got electronic ignition, what it the correct BTDC value? I'm guessing it should be 8 degrees or 10 degrees? Thanks in advance! Cam79, The different specs are relative to the market the car was originally manufactured for. Assuming you are in the USA w/ a USA Market car, your car is spec 10. This means that you have a Lucas Constant Energy Ignition 45D Distributor (electronic, w/o points). The static timing spec for this car is 10°BTDC @ 950RPM ± 50RPM. Because you have a centrifugal advance of 16°, your total advance would be 26°BTDC @ 3,000RPM. Because the 907/910 engine likes advance up to 32°BTDC, you could advance the static timing to as much as 16°BTDC, although I suspect that this would be too high, but anywhere between 10° & 14°BTDC would be good. I would split the difference and go for 12° and see how you like it. Happy Motoring! ...Jim'85TE

Sorry Jim, but spec 10 is for the Esprit/Excel HC engine. An 83 Esprit N/A will be spec 9. Depending on the exact date of manufacture, it will have Lumenition or the Lucas Constant Energy system.
The TOTAL advance (i.e. combined static and centrifugal) is quoted as 25deg at 3500 to 4000 RPM. This is the recommended way of setting it. The static advance is not really that critical
Unless the centrifugal advance mechanism is in 'as-new' condition, I would strongly advise not to set it any higher than 25deg, otherwise there is a strong risk of pinking due to far too much initial centrifugal advance at relatively low revs. This is a result of the springs that control the advance being stretched over time. An easy way to check for this is to remove the dizzy cap and see how much angular play there is in the shaft before spring resistance can be felt. If there is any at all, the springs are stretched. Fit a recon dizzy if required, and then think about increasing the factory spec total advance if you wish.

Paul.

[CAM79]

Thanks for the advice guys, I'm in the UK, and car is of UK spec, the dizzy definately doesn't have any points. Right, time to time her up...

Oh, according to the VIN plate it's the 912 engine as I would expect, the engine numbers match, but the cylinder head has 907 stamped on it, is this correct?

Cheers!

>> Edited by CAM79 on Friday 2nd July 17:08