TR6 Vacuum Gauge Timing

[SherpaPilot]

I have read about an alternate technique in setting engine timing by using a vacuum gauge. I have tried this method on both my TR6 and my 65 Stingray, both resulted in outstanding performance. Having said all that, I am learning this advanced timing afforded by vacuum setting may result in excessive cylinder head temperatures and could cause bearing failure. I have returned my timing on the TR6 back to 4 degrees ATDC but has resulted in lesser response and poor performance. On the other hand, I do not wish to destroy a perfectly good engine either. Does anyone have any experience in this area?

 

[poolboy]

Yes, I use a Vacuum Gauge as a visual reference tool instead of damper marks when setting the ignition timing.

 

[Geo Hahn]

Timing is timing however you get there -- which method you use doesn't affect performance except to the extent that a particular method results is slightly too advanced timing which may yield the perception of better performance but cause other problems.

I still set it static and adjust it under driving conditions -- but finish by using a timing light to see what total all-in advance looks like. I would think a limitation of timing by vacuum is you do not know where you ended up - unless you then use a timing light to check it. For me - quantifiable and repeatable is best.

 

[TR3driver]

The 4 ATDC figure is only for when the vacuum retard is connected and operating. Sounds like maybe yours doesn't work, or is not connected properly
Another possibility is that the timing mark on the damper has shifted, as Ken mentioned.

 

[SherpaPilot]

Thanks guys. After posting my question, I double checked the manual. The static timing for a 72 TR6 is 12 degrees BTDC. I set that in static mode and will see how it works out.

 

[poolboy]

Once you do, hook up your Vacuum Gauge for reference.