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bunzil
01-20-2014, 05:43 PM
A few years back I finally removed all of the stock pollution gear from my 76 TR6 including plugging the EGR valve. I didn't give it much thought at the time but today stumbled upon an articled I'd cut out a while ago about disconnecting the vacuum retard on the distributor as well. This makes sense but I thought I'd ask anyone else their experiences in this regard.

Should I disconnect it and re-time the engine and if so, what's the best method? Merely advance it till it pings then bring it back?

Thanks in advance.

poolboy
01-20-2014, 06:07 PM
I use a vacuum gauge connected to the Anti Run-on Nipple on the intake manifold's banjo fitting.
https://i233.photobucket.com/albums/ee300/poolboy_album/TR6banjo.jpg (https://s233.photobucket.com/user/poolboy_album/media/TR6banjo.jpg.html)
If you are at sea level a Manifold Vacuum of 17 to 18 in-Hg at 850-900 rpms will get you in the ball park.
Although you can advance the timing into the low 20's when the tach cable is disconnected, I would not recommend advancing that much.
I don't think you'll have pinging at 18 but listen for it anyway.
Be sure to get a good seal on the vacuum nipple on the bottom of the carb, too.
https://classicinlines.com/vacuum.asp

bunzil
01-21-2014, 04:03 PM
Gee, I've never used a vacuum to time the ignition, but I'll give it a go. But I still didn't get confirmation about removal of the retard unit. Yes?



I use a vacuum gauge connected to the Anti Run-on Nipple on the intake manifold's banjo fitting.
https://i233.photobucket.com/albums/ee300/poolboy_album/TR6banjo.jpg (https://s233.photobucket.com/user/poolboy_album/media/TR6banjo.jpg.html)
If you are at sea level a Manifold Vacuum of 17 to 18 in-Hg at 850-900 rpms will get you in the ball park.
Although you can advance the timing into the low 20's when the tach cable is disconnected, I would not recommend advancing that much.
I don't think you'll have pinging at 18 but listen for it anyway.
Be sure to get a good seal on the vacuum nipple on the bottom of the carb, too.
https://classicinlines.com/vacuum.asp

Healey_Z
01-21-2014, 11:31 PM
Remove the retard line from the carb, plug the port and re-time the car per Poolboy's advice and you will be golden.

poolboy
01-23-2014, 04:59 PM
You can do as Healey-Z says and cap the vacuum source on the bottom of that front carb. Notice when you do disable the retard, the idle speed will increase a bit.
You want to monitor the vacuum readings at your normal idle speed, so a little adjustment of the "throttle stop" (idle speed) screws may be called for during the procedure.
Increased idle speed (up to a point) as the timing increases is an indication that the engine is running more efficiently.