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Stroboscopic Timing - 1275 cc

Jer

Jedi Warrior
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The only mention I have on the stroboscopic timing setting for my 1275 cc is in my Haynes manual that sort of mentions 9 degrees, but it doesn't seem clear, does anyone know what the value should be for my stock 1967 1275 cc ?
My car runs fine & doesn't "ping" or run on after I shut it down so I think I must have it close but thought I would verify here.

Thanks
 
Not sure I understand how the manual can "sort of" specify a value--it should say it specifically or not at all. Or so I'd expect.

In any case, few of us really time cars to the spec any more. Gasoline has changed and distributors have worn. So, a good method is to start with the spec and experiment a bit. If it doesn't ping, you're not too far advanced. Also, remember that the timing spec is with zero advance, and unless the idle is very slow, you might have a degree or two advance at idle.

My bugeye, with a 5-degree spec, is now closer to 10 degrees at idle. Runs fine. No pinging at all.
 
I set mine to 32' at full advance & it pulls nicely.
 
The "book" says..

from 12CC/Da/H16300:
Static time to 7 degrees
stroboscopic 22 degrees at 1200 rpm --13 degrees at 1000 rpm
Engine idle speed 700 rpm hot.

from 12CE/Da/10:1
13 degrees at 1000 rpm.

from 12V/588f/H101 and 12V588F/L101:
16 degrees at 1000 rpm.
 
Perfect, thanks Bill, that's what I was looking for.
Just for fun I wanted to dial it in to what "they" say it should be & see how it runs... of course as others mention above, then I will probably bring it back to where I have it now :smile:

Thanks
 
There is a guy, called "poolboy" on the Triumph forum that has worked out a very successful method of setting timing with a vacuum gage. He figured it out because our cars have so many effects from aging that often the timing marks on the crank pulley no longer relate well to where the timing should be set. He is a good guy and I am sure would be more than happy to explain what he does.
 
tomshobby said:
There is a guy, called "poolboy" on the Triumph forum that has worked out a very successful method of setting timing with a vacuum gage. He figured it out because our cars have so many effects from aging that often the timing marks on the crank pulley no longer relate well to where the timing should be set. He is a good guy and I am sure would be more than happy to explain what he does.

If you can confirm that the TDC mark is correect, no one has bent ta tab, then TDC is TDC palin and simple, I always add top timing pointer on my A series engine rebuild anyway Both Drew and Ray's engine have this on them now), what drunken factory worker's idea was it to put in on the bottom anyway. You may get slop i the system for distributor shaft pay form a worn shaft bushing, or wear or slop on the gear. Normally somewhere around 10-15 degrees on a vaccum advance unit at idle will net you somwhere around 30-35 degree at total advance which should happen by 3000 rpms. when checking a vaccum adavnce unit at idel you should disconnect the vccum form the distributor and plug it on both side, then reconnect the vaccum line and check the total at the the 3000 rpms.
 
Following Hap's post, here is how my timing pointer is set up on my MGB. Different engine but same idea. I used a MSD Timing sticker (PN 8985)I bought from Jegs for a 5.25" pulley that came with my Supercharger. With my B, Iinitally set timing around 15* BTDC and then at 3500 RPM around 32* or until it pings.
 

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Nice work. Lovely.
 
Thanks John, I think I will put that on my list for the fall engine pull.
 
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