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MG TD TF 1500 - Dizzy Install

Quick questions...my dizzy is not installed correctly, has probably been like that from when I Dad had her, she runs okay but I'd rather pull the dizzy, clean it up, and see about getting it in the right way and redo the timing. Is there a way to test the springs or for such a low cost item should I just replace? Also, am I correct in understanding that the advance is not adjustable, that is preset in the dizzy design by the springs and weights, so the only thing that is adjustable is the static timing?

Thanks all,

Steve
SD Denham

The dizzy can be installed in any orientation and run well, providing its timed correctly. Advance is controlled by the springs and weights. Static timing controls the starting point, which it is generally agreed with modern fuel should be a few degrees in advance of TDC. Swopping the springs is not quite that straight forward, the two springs are different and require expertise to select the right springs. In addition the distributor may be worn. I guess you have a choice - if its running well, maybe then leave it alone, or if not then send it to Advance Distributors (recommended), or read all you can and fix it up yourself.
Dave H
Dave Hill

Steve,

If you want it better than new, send it to Advance.

A very satisfied customer.
Jim
James Neel

Agreed, orientation doesn't make any difference other than ease of maintenance. Not sure where you are in California but if in So Cal you can also take it to Jerry Felper of British Auto Electric. Or ship it to either one of course. If it still has the original advance curve then your engine will benefit from an updated curve to suit modern fuels. Also make sure there isn't excess vertical or lateral play in the unit. Both will cause problems.
Steve Simmons

HI everibody
I know about the original curve. But dos someone know about the "updated curve" ?

Laurent.
LC Laurent31

You can get a pretty good idea whether it is advancing using a timing light. Once you see it is retarded at idle and advancing when revved, without bouncing wildly back and forth, you can move on to delving into springs and curves. If you trust your tach, you can plot the curve with the timing light.

I just happen to be installing a dizzy on our highly modified XPAG and am doublechecking idle and advanced timing statically with a Volt-Ohm Meter. Roll the crank to TDC , then rotate the dizzy to where the VOM says the points are just opening when the crank rotates in its normal clockwise direction and lock it down momentarily. Then I twist the rotor advanced and slowly turn the crank forward to where the points are just opening and note what degree it is at. I'll go back and forth a few times to get to where I'm satisfied the point will open. Now I can tell how many degrees of advance to expect. It won't tell me at what rpms it'll fully open nor the curve, but I'll know pretty closely how many degrees it'll advance. To me, the important adjustment is to set the timing where it is advanced at power, and not get too many degrees advanced there, and then live with that distributor position for idle.

My son had a brand new ZZ454 crate motor installed in his pickup truck which crapped out in only 400 miles. Idiot so-called mechanics couldn't even install a crate motor without nearly destroying it, starving it for oil and installing the wrong distributor gear which turned into steel filings. When I reassemble the engine, I noticed they stuck a rusty MSD distributor in and the shaft had corroded solid. It thushad no mechanical advance and that engine doesn't use a vacuum advance.
JIM N

I've heard recommendations for Advance numerous times, I guess they are like the Joe Curto of distributors :-)
SD Denham

I just had mine rebuilt by Jeff at Advance, and he also did my Sunbeam Alpine dizzy. He does excellent work for a VERY reasonable price. The curve he gave me for my Sunbeam totally transformed the car's performance. I haven't had time to try out the new TD dizzy - the weather is just getting spring-like here in Philly - but I'm sure it will do the same for that car, too.
Kevin McLemore

Jeff at Advance is the dizzy guru. Simply give him your engine specs ie cam, compression, performance mods, NA’d or SC’d along with your dizzy and he’ll set it up right for you.

Bill Chasser
TD-4834
W A Chasser

OK, so I just installed my rebuilt dizzy from Advance (Jeff)... it works GREAT. Money very, very well spent.
Kevin McLemore

Only caveat to re-install orientation...make sure the side terminal is installed away from the speedo gearbox..I have read of those shorting out the ignition as they wobble around during a drive.
Regards, Tom
tm peterson

I always oriented mine away from the tach drive gearbox for that reason. Since then, I've figured out that if you place an o-ring into the female side before installation, it will stay put (by friction) and never hit the dizzy. "Never" in this case meaning mine hasn't budged in about 5 years since I put the o-ring in it. But I still leave the dizzy turned just in case.
Steve Simmons

This thread was discussed between 27/04/2018 and 04/05/2018

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