[TR] TR4A - Tuning Update 2

John & Pat Donnelly pdonnel1 at san.rr.com
Sun Dec 15 20:33:00 MST 2013


Hi Geo,

Where did this chart come from? Do you know what weights and springs were
used on each model? Something doesn't seem correct here.

Thanks!
Johnnie


> 
> I think the most important number is the advance when everything is
> 'all in', i.e. at high RPM.
> 
> http://i1214.photobucket.com/albums/cc499/Ahwahnee18/TR4/Lucas_Distribu
> tor_Advance_Curves_zps03074f01.gif
> 
> Any retarding you do at idle will, irrespective of how smoothly it runs
> there, rob you of power at speed.
> 
> Geo
> 
> 
> On Sun, Dec 15, 2013 at 4:47 PM, Jerry Van Vlack
> <jerryvv at roadrunner.com>wrote:
> 
> > It will run smoother but will it have any power @ 4 degrees after
> TDC?
> >
> > Nice catch!!
> >
> > That should be "ATDC"..
> >
> >
> > On Dec 15, 2013, at 4:12 PM, Geo Hahn wrote:
> >
> >  On Sun, Dec 15, 2013 at 3:03 PM, G.D. Huggins <guy at genfiniti.com>
> wrote:
> >>
> >> ... I statically timed the engine, then retarded to 4 degrees BTC,
> >> and the
> >>
> > engine
> >
> >> runs smoother than ever!...
> >>
> >>
> >> 40 BTDC is advancing the timing, not retarding.  And yes, advancing
> >> helps so
> >>
> > long as you stop short of pinging.
> >
> >>
> >> Geo


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