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The next project is twin charging, which means adding a turbo charger to the supercharged engine. I bought a Volvo Penta (marine engine) non-return valve. It will come between the supercharger and the turbo and it should open when the turbo needs more air than the supercharger can supply. The size of the sidepipe for the supercharger is 70 mm and the size of the main tube is 80 mm.

I decided to buy a TIG welding machine so that I don't have to ask help with every little welding job. I found a nice machine at Stahlwerk. Maybe I can weld something with this machine some day ,-)

Turbo manifold version 3 under construction. The geometry is difficult as usual, luckily a big hammer is handy in fine tuning.

The turbo manifold is almost ready. Still need to paint it and to straighten and cut the flange. The 2.5 inch downpipe and exhaust pipe are ready. The wastegate springs range from 0.5 bar to 1.5 bar. The next job is the turbo oil and water lines.

Here are a few pictures from the engine compartment.


The water lines are almost ready but the turbo coolant system is not ready. The turbo oil return line and the breather system are not ready.

The breather and the turbo lubrication and cooling are the next jobs.The new radiator is in its place.

I had the car dynoed at and the official pwer is 178 kW with 0.6 bar boost which is near the max rating allowed for this car (180 kW). Another test with 1,0 bar wastegate spring gave about 0.7 bar boost and these results. The Eaton M62 blower was free wheeling. The dyno service was very professional and I got a few tips for the setup, too.

I ran a new best ET of 13.777 / 103.4 mph (13,777 / 166,44 kmph) at the VW Open meeting at Kiikala airfield. The estimated power at the wheels is about 250 hp. Maximum boost was 1,05 bar (about 15 psi).

New best ET at Alastaro Circuit  13.375 / 105-61 mph (169,96 kmph)

The engine broke on a flying mile run at Lappeenranta air field. Now I finally bought an old Mercedes 309D for transporting. I bought the trailer ramps from  Trailerikeskus Siikala- Special thanks to Ari Koponen and Rauno Sinersalmi from Lappeenrannan Ilmailuyhdistys for their help with the car.

At least two pistons broken-

2.3 litre kompressor engine bought from Sweden, thanks to  Norrbottens Bildemontering

The engine is in place but there is yet a lot to do.

New best ET at Kiikala Burnout Partyssa 13,230 / 106.167 mph (170,86 kmph) and 60 ft 1,964 with the new engine. The blower (kompressor) is on when TPS is more than 45% and boost less than 0.8 bar (abs. 180 kPa). The turbo gave 1.0 bar boost (abs. 200 kPa). The car runs OK, but the ET Street Radials are losing grip at the start line.

New best ET at Boxer Speed Day in Rayskala is 13,077 / 106.571 mph (171,51kmph) and 60 ft 1,951 at another run. Max boost was about 17.5 psi (abs. 220 kPa).

I am trying to make the cooling system better regarding the engine, the boost lines and the turbo because I had overheating problems in normal highway driving. The new charge cooler is an air to water intercooler with a core size of approx. 4 1/2 x 6 x 11 inches.

I will also change the order of the chargers so that the SC (komprerssor) blows air into the turbo, An electrical throttle valve acts as a bypass valve and gives uncompressed air to the turbo when the SC can't handle the air flow.

This will be the new bypass valve. The 68 mm (2.68") throttle body is from a Mercedes M112 engine ( and the flanges are made by ProLaser Oy with good quality and a fast delivery.

The story continues on page 2015