RE: CAMS

[Formeister@xxxxxxx]

To Chip Schug:

>I understand that I ultimely need to go to WEBER 45's and a ported and
polished head...<

I've done similar mods (and then some) to my 1750, bored to 81mm, and found
that the keys were:

1)  Having the right emulsion tube for the carbs (40 DCOE's).  The F-9
supplied with the conversion kit were far inferior to the F-16.

2)  Tried various size venturies, best I found for street use was the 32mm
though I understand the optimal would be to bore out the 32's to 33.  Higher
flow speed, though less volume of air created better turbulence hence
combustion.  130 main and 200 air corrector worked best with the 50 f8 idle
jet.  I have 34 and 36mm venturis plus assorted jets etc. if you'd like to try
them.  

 BTW the Alfa Comp Ref book lists the carb settings at 36mm vent, 150 main,
160 air corr, f-16 emulsion, 55F12 idle - obviously set up for flat out.  

>...am using the Marelli Plex ignition system.<

3)  Ignition Timing should be set to the max. setting - don't bother with the
static.  With the Marelli-Plex I run max advance at 34 degrees.  Ignition
Timing in the Comp. handbook sets fixed at 3 degrees BTDC, +18 deg. @ 3K, +31
@ 4K, +32 between 4.5 & 5.5K  and a max of  33 between 6 and 7 K rpm - these
sound good for a street or modified engine.

>I am still trying to find the "right" cams or the right setup...<

4)  Cam timing really important.  You can set for better low end torque or
flat out running.  102 degree lobe centers works best for the street on my 8L
cams, less than that and I was disappointed in low end grunt.

>My Spider has a lot of "power", but I can not get the car over 100 mph
>without going over 5500 rpm in 5th gear.  It is almost like my spider is
>not using all of the freshly aquired power in an efficient manner.  

5)  Make sure the Emerg. brake's off ;-)  Just kidding,  but did you mean you
can only take the rpms up to 5500 in 5th?

Finally, I've heard from reliable sources that the key to making power in the
Alfa's lies in the breathing and compression ratio.  Make sure the exhaust's
not restricted.  Though it's a science and everyone has his own opinion I've
heard a good set up is the Try-Wye set up with 22" primaries and 18"
secondaries.  Got to be carefull of going to large on the diameters as you
want the gas speed up to help the scavanging.

Sounds to me you're heading in the right direction,  just takes time setting
things right.

Regards,

Frank Formeister

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