<VV> LM Engine Questions

[Andy Clark]

See comments below.
Andy Clark
Camano Island, WA.
66 140/4 Monza Sedan
66 140/4 Stinger Clone
66 180/4 Cord 8/10 #60
----- Original Message ----- 
From: "Rodney Sampson" <rsampson at kc.rr.com

>    A few engine questions  (65 140Hp)
>
> 1)  Did a cylinder pressure study...
>       1-150 3-175 5-180 2-150 4-160 6-150
>       At what point should I consider rings ?

You don't appear to need compression rings yet. 20% compression variation is
my  rule of thumb for determining when new rings are required. Ummmm.....on
second thought the 150 vs 180 readings suggest that you may be getting
close. I'd pursue other lines of investigation forst, though- see below.

>
> 2) At present, I consume 1 qt of 20w50 oil per 40 mi run to and from
work...
>      excessive blowby and plugs 3 and 5 get fouled atleast once a week.
>      With the above readings , I am assuming bad guides, anyother
> possibilities ?

Bad oil scraper rings will cause oil comsumption. Have you checked the
condition of the seals on the intake valve stems? These would cause
excessive oil consumption. The blow-by could be caused by worn exhaust
guides. Excessively bad guides will also affect compression readings, since
the valves tend to bounce around before reseating.
>
> 3)  Lifters, I'm considering replacing them all but the blurb from
> Clarks advises
>       against replacement on an old cam. I've got a couple that are very
> sensitive to
>       oil levels/pressure...Comments ?

Do not, repeat, do NOT use new lifters on an old cam (or vice versa, for
that matter). What do you mean by "sensitive to oil levels/pressure"? Do
they pump down when the engine is off? How does oil level affect them? Do
you happen to have a deep alum oil pan without an extended pick-up? That
could cause the pump to pick up air under cornering, the oil pressure to
drop and a leaky lifter might collapse. Need more data, though.