[alfa] Re: alfa-digest V9 #1120 - spider S 4 valve questions

[AlfaNeely@xxxxxxx]

In a message dated 2/6/2004 6:14:23 AM Central Standard Time, 
owner-alfa-digest@domain.elided writes:
Date: Thu, 5 Feb 2004 21:37:46 -0700
From: "C.M. Bereznoff" <cmbereznoff@domain.elided>
Subject: [alfa] spider S 4 valve questions

Hello Alfisti,
    My 93 Spider recently developed a loud sharp metallic
click click.  Stared rather suddenly  ( after a teenager
likely drove the living H-ll out of it. ) It occurs only
when starting from a standstill and initating forward
motion.  It lasts 4-5 ticks, a few mph and quits. Seems to
occur more often whne the engin is warm and the oil
viscosity is lower. It runs well otherwise.  67K miles on
engine.  Last valve adjustment at 51K ( previous owner let
it go to 66 K without the 60 K adjustment ).  Now the
questions!

1. does this sound like it may be a broken or cracked valve
spring?

2. I am sending it to the shop next week for analysis and
valve adjustment.  If the spring is cracked and the head has
to come off, what opinions are out there regarding having
oversized valves put in?

    advantages?,
    disadvantages?
    performance improvement worth it?
    who has the best oversized valves out there?

3. What about changing out the cam shafts for a different
lift and angle for increased performance?

I want to thank everyone who has so generously replied to my
queries in the past.  What a great group that always helps
out!

Dr. Craig M. Bereznoff
Longmont, Colorado
1993 Spider
--------------------------------

    See my previous response on the lack of need for a performance increase 
in the Motronic spider.  My recommendation for improving the L Jetronic spiders 
is to use Motronic pistons, a higher lift intake cam and open up the exhaust. 
 In other words, bring the early spiders up to Motronic specs.
    Large valves might help marginally, but are very expensive for the gain.  
On a full race engine, large valves maybe be good.  On a stock engine there 
are better ways to increase performance.
    At 67,000 miles the valve springs should still be OK.  However, that 
could be the problem.  You could have a broken or weak spring.  A check of the 
valve clearances should tell the story.
    By the way, the teen ager running the dickens out of the car should not 
hurt.  Is that not what we on this list call an Italian Tune Up?
    If you have to play with the camshafts, be aware that the Motronic intake 
cam has a larger base circle with shorter intake valve stems.  Cams designed 
for the L Jetronic and earlier Alfas will not work without other modifications.
    The Motronic intake cam has 11 mm lift, but no more duration than earlier 
cams.  You might go for more duration, but you do need to retain the VVT.  
Without the VVT, the electronic injected Alfas start and idle poorly.
    The Motronic exhaust cam is basically the same as earlier Alfa cams with 
9 mm lift.  Going to an exhaust cam with about 10 mm lift and a bit more 
duration could help.


Ciao,
Russ Neely
Oklahoma City
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