Egil wrote...
[munch..]
>
> Exhaust valves are quite another matter altogether. Cars with valve seats
> machined in a cast iron head can develop trouble with the exhaust valve
> seat recession. The problem is much more pronounced with hard driving/
> high temperatures, if you just cruise around town you won't notice.
>
Valve seat recession in older cars has been a big concern in New Zealand
since the abolition of leaded fuel here early last year (1996).
The fuel companies promote a product known as Valvemaster which does not
cut the mustard IMHO. Other upper cylinder lubricants (eg. Flashlube) are
also available, but these involve adding with the fuel or kits which
introduce the additive at the inlet manifold.
As reported previously, I have bitten the bullet and bought a Fuelstar unit
which has a high initial cost ($NZ225 for a 0 - 2000 cc vehicle, $NZ340 for
2000 - 3500 cc) and I can honestly say that the car is going really well
and does not suffer VSR even though no additive is used. As well as
stopping VSR by using tin (which is used as a substitute for lead), it also
'conditions' the fuel by adjusting the fuel molecules making them smaller
and easier to burn. The result is definitely more power, better (by 20% in
my case) fuel consumption and therefore much more driving pleasure. Their
advertising also shows that emissions in all categories are significantly
improved.
In talking with the local rep recently, he was saying that the product is
going through final tests prior to getting approval in California and the
rest of the USA and that the testing has been very positive. They are
already marketing in several other countries.
They have a web page still under construction http://www.fuelstar.co.nz
I have no commercial connections with the company or its products. I am
just an extremely satisfied user.
David Greed
1979 2500S
Email: greed@wave.co.nz (Home)
sys_dwg@niw01.telecom.co.nz (Work - VAX)
david.greed@telecom.co.nz (Work - PC)
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