Samstag, 20. September 2008

MOMO Vega Wheels 6 x 14"

The Vegas finally are powder coated, tyres 185/70 R 14 (with tubes) are mounted. The steering needs less effort when driving in a bend or parking compared to the former 195/60 R 15 Bridgestone. However steering characteristics offer a very good increase in handwheel force over lateral g's.

Mittwoch, 17. September 2008

Neuenbürg Castle Sept. 15th, 2008

These are the Alfa participants of the 2008 Neuenbürg Event in the old castle yard.

Sonntag, 14. September 2008

Speedometer Optical Tuning

An additional 12V 4W instrument light bulb with it's BA9S socket is mounted on the back of the speedometer housing. On my car instrument ligths are very weak.

I recently had to open the speedometer because of a failure. By the way I cleaned the mechanics from dust and grease and put the SNO logo and the gear switch pic on the dial. Both are decals printed with an inkjet printer. The gear logo is scanned from the Giulia manual. The checkered flag showes the city limit area.
The speedo accuracy can bei easily adjusted on Jaeger instruments by a screw on the back side. Odometer rolls (km) can also be tuned independently.

Dienstag, 2. September 2008

Mini Catalytic Converter

Why not supporting environmental protection with our historic cars? Here is an easy and cost effective way to integrate a catalytic converter into the exhaust system. I use the Tenneco Walker Mini Converter. I has a diameter of 55.5 mm and was planned to use in the Audi Coupe 2.3l 5-Cyl. (Walker type no. 52590-03W). Other diamerters (42.5 mm, 45.5 mm, 50.5 mm) are also available.

The converter is intergrated in the exhaust pipe just behind the 2 in 1 tube of my CSC sports exhaust system with stainless steel pipe clamps. Sealing compound is recommended. It should be mounted as near as possible to engine's exhaust ports.

There is no special engine control system. I run stock Weber 40 DCOE carbs. Ok, this is not very effective in terms of emission reduction but better than nothing. I can't measure any significant engine power reduction due to the
streamlined sheet metal catalyst technology.

Samstag, 5. Juli 2008

High Beams Finally Mounted

Here are the original chromed Bosch high beams mounted on the GT junior. You see the protector caps I taylored last year.

Mittwoch, 2. Juli 2008

7. Veteranenausfahrt MSC Weil der Stadt

Saturday, 28th of June I finished 3rd at the historic rallye of the Motor Sport Club Weil der Stadt.
It's not worth complaining but I could have been first in my class. At trial no. 3 my bicycle odometer showed wrong speed values. I couldn't keep the average speed of 30 kph and got 33 penalty points - what a mess!

Tho photo shows a BMW Dixi with a rare "Ihle 600" body behind the Volvo. The BMW- or Dixi Ihle has a wooden handmade body on a 3/15PS chassis manufactured between 1930 and 1934.

Momo Vega 6 x 14" Alloy Wheels

Recently I got the chance to buy a set of four aluminum wheels. They are called MOMO "Vega" dated from 1972. MOMO is an italian manufacturer - you might know their steering wheel collection. The size is 6 x 14" fitting exactly on the Alfa GT junior. I found out that the rims are rather 6.5 that 6.0 inches. This will give a good cornering stiffnes with my Barum 185/70 R 14 classic tires. There is no H2 hump - so there is no chance to use tubeless tires. The well known Alfa hub caps of the 5-spoke Cromodora CD-35 wheel are supplied with these outstanding contemporary wheels.

The wheels must be glas-sanded and re-painted. Silver paint or two-colour black/silver would be nice. Even powder coating would be possible.

Samstag, 14. Juni 2008

Cylinder Head Preparation - Part III (final)

The engine finally is reassembled and the new cylinder head on top. You can see the intake prolongation parts (+40 mm) between the Webers and the head. Because of these the air filter is very near to the left fender. I had to move the MSD 6 ignition box to the firewall (under the ignition coil).

I left my concept an fitted a different exhaust cam. It's a Heimbach 30A cam (278° duration, 10,0 mm lift, 0,30 mm valve clearance).

Fuel Gauge Sender Repair

Suddenly the needle of the original Jaeger "benzina" gauge got stuck. It was not an electrical problem as I though on a first glance but the potentiometer strip inside the in-tank sender had reached the end of it's life. As a first aid I repaired the broken wire with a constantan resistor wire (see next photo).

Later I dismantled an old fuel level sender and made a repaired new one out of the two old parts. The potentiometer housing can be opened easily by bending three sheet metal clamps.

Now everything works fine again. It would be wishful to have some more damping at the needle. To achieve this the friction between the potentiometer pick-up axle and the sheet metal plate (electric ground) can be increased by fitting a small shim. The eight screws on the flange are M8 x 12.

Sonntag, 17. Februar 2008

Modified Tappets

The valve clearence compensation problem on the intake side is solved by modified tappets. The bottom of the right tappet is machined on a lathe down to 6.60 mm thickness instead of 7.30 mm. Alfa 105 tappets (left) usually only have 3.25 mm.

The new tuning tappet (right) has 42 g. This is a 3 g saving over the original Alfa 105 tappet. Now valve clearing compensation with Alfa shims which are available from 1.50 to 3.50 mm thickness is possible in combination with reground camshafts. A good adress to find these tappets ist histo:tec in Germany or tuning shops supplying Volkwagen/Audi parts. So called "mechanical tappets" are available for VW Golf GTI or Audi 20V engines to replace the hydraulic ones to achieve higher revs. They must have a diameter of nearly 35 mm.

Donnerstag, 10. Januar 2008

Valve-clearance Compensation


The new cam with smaller base circle requires a different valve clearence compensation at least on the intake side. The exhaust valves I use have 1 mm longer stems. Here adjusting the correct lash (0.45 mm) with normal Alfa shims is no problem.

J. Kartalamakis recommends to use regrounded Volkswagen Golf Shims (see next photo) or special custom made steel shims. Higher shims than 3.50 mm are reported to be available at Gozzoli in Italy .
In my special case I would need modified shims from 4.85 mm to 5.35 mm thickness.
My solution to that problem are modified tappets with a thicker bottom, see post above.