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Sun May 20, 2007
17:40
This has been a good weekend for tinkering in the garage - it's been lousy weather:
Mk2 in the rain


I spent some time refurbishing a couple of throttle bodies - one of them is for our A3 Golf:
OBD-II A3 throttle body


I've also been practicing polishing valve faces. I'm getting closer to completing the ABA engine rebuild, so it's time to think about the cylinder head and valvetrain. Polishing the valve faces helps reduce carbon buildup, and also helps hot spots from developing (which could lead to detonation problems). I will be polishing the combustion chambers in the cylinder head as well, for the same reasons. I'll be having 0.060" milled off the head, and then compensating for the 1.3 degree cam timing error by using an adjustable cam gear. The final compression ratio will be 11.5:1 - so I need to do everything I can to promote efficient combustion. I have a decent technique for polishing the valve faces, which involves glass bead blasting (to remove carbon buildup) followed by rubbing with crocus cloth and WD-40, and then using a power drill to spin the valve against a soft cloth with Brasso metal polish. I haven't been able to get a perfect mirror finish yet, but I can get them shiny enough to see reflections:
Polished intake valve


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A1 parts for sale:
intake air preheater hose
Item: Intake air pre-heat hose (from exhaust manifold shroud to air box), for Scirocco 2 (1982+)
Condition: New
$12


A2 parts for sale:
A2 GTI dual round grill, with inner lights
Item: GTI dual-round grille with inner lights, bulbs, and lower trim strip
Condition: Used, lower trim strip is weathered.
$35

parcel shelf strap
Item: Parcel shelf strap, 3 available
Condition: New
$3.50 ea.

A2 valve guides, 8 valve
Item: 8 (eight) valve guides, German, standard size, for 8 valve head
Condition: New
$24

wheel cylinder
Item: Wheel cylinder (for rear drums, obviously), 2 available.
Condition: New
$12 ea.


A3 parts for sale:
parcel shelf strap
Item: Parcel shelf strap, 3 available
Condition: New
$3.50 ea.


A4 parts for sale:
ALH water pump
Item: OEM Water pump, ALH engines
Condition: Used, 130,000 miles
$20