My MKII (MKIV 1296 engine) does something very similar. I started incrementally
advancing the timing expecting it to starting pinging at some point under load.
Ended up with the advance slightly off the scale. It now runs significantly
better than with the spec timing although I don't try and rev it much above
4500. I believe that the advances are working correctly.
I have a single weber and crane ignition. I'm pretty sure that my mixture is a
quite rich and was wondering if that had something to do with it.
One other thing, when I had the twin SU's it would definately ping when
advanced even slightly more than spec. I also ran it pretty rich with the SU's
although there was quite an air leak.
I guess as long as it doesn't ping and it runs well (enough for me) then no
problem?
Mark Sinclair
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>after reading this timing related post, I just have to ask the rest of this
>list about something- my 76 with single Weber DCOE and stock distributor
>just wouldn't go (bad hesitation) below about 2800-3000 RPM, so I decided
>to try fiddling with the timing- I thought as long as it's not pinging and
>doesn't overheat, it was worth a try
>I ended up with the thing advanced off the scale, I mean *off* the scale,
>right now the timing mark is roughly aligned with the edge of the
>thermostat housing/upper hose connecter and it runs great! I think it must
>be at least
>25-30 DBTDC and it advances further as expected at higher RPM-
>I recently had a similar experience with my friend's (late) MGB that had
>been converted to dual SUs
>I suppose I'd fail my smog tailpipe sniff next spring, but I'm flabbergasted
>has anyone else had similar experience? I guess I wouldn't sweat getting
>too "exact", Alan
Joseph R Schneider Web Page http://pubweb.acns.nwu.edu/~jschneid/JRS.HTML
76 Spitfire 1500 FM45587UC Ilinois license plates "SPIT BOY" VTR #11526
*Spit happens*
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