MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

Recommendations

Parts

TR parts and Triumph parts, TR bits, Triumph Car Spares and accessories are available for TR2, TR3, TR3A, TR4, TR4A, TR5, TR6, TR7, TR8, Spitfire and Stag and other TR models are available from British car spares and parts company LBCarCo.

Triumph TR6 - Timing

So as you guys know, the car is running. So I went to do the timing with a timing light and I cant get it to 4 or 8 BTDC. I rotate the dizzy as much as possible and it seems the closer I get to 4 or 8 BTDC the car starts to run more rough. Any Ideas? I havent driven it yet becaue shes not done yet, so I cant answer what the accelerating is like
SBF Fitzgerald

Firstly, well done getting the car running - I had a similarly frustrating experience after rebuilding my engine a few years ago, which turned out to be due my my attempt to set the timing - I had rotated the distributor so much that I had moved to the wrong plug...

From what you said, it appears that you are trying to set 4-8 BTDC with the car running - isn't 4BTDC the static figure? This would be set using a test lamp with the engine off, rather than a timing light with engine running at idle. According to my manual, 4ATDC is correct with the engine running. Of course, this will depend on your vacuum connections - are you running just centrifugal advance, or the vacuum advance also? If you have had the distributor recurved (Jeff at advance distributors did mine, but I think it is pretty much stock) then the 4ATDC would change also.

Hope that helps - I won't pretend to be a timing expert!
Cheers
Alistair
A Hewitt

Another way to set it is by a vac gauge.You got one of those?
Unless the damper has been rebuilt.You can't tell if it is still correct
Don Kelly

See if your distributor has not been installed 180degrees wrong. The engine will still run but very poorly.
Kypros Christodoulides

Ive never done vacuum timing before. The dizzy was never removed from the car
SBF Fitzgerald

http://automotivemileposts.com/garage/v2n8.html
Don Kelly

Well, with a vacuum gauge you can find many faults on an engine. To set the timing you connect the gauge to a vacuum port and keep advancing the timing until you get the maximum amount of vacuum reading on the gauge. What reading you get you divide by 2 and add 10% on top.
This is how I was instructed to do it.( the 10% on top I add,as it seems to improve things) If you don't have a vacuum gauge get one from gunsons,they are the cheapest on the market,or try e-bay.
Kypros Christodoulides

Interesting article Don, but the way they describe it you do not really need a vacuum gauge. Just give it as much timing as it will not ping and test drive. If it pings , retard a little until it stops pinging at heavy loads.
Kypros Christodoulides

I always heard, ,give it all the vac you can and then back a little
Don Kelly

Yes Don, the principle of the thing is that the I.C engine is like an air pump. The more vacuum it produces, the more efficient it is.
Kypros Christodoulides

This thread was discussed between 21/03/2012 and 24/03/2012

Triumph TR6 index