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I have been busy and the car has waited. Now i should chenge the cylinder head gasket and build the ignition box. This picture shows the ignition box the amplifier and the programming tool kits and the 1.5 bar MAP sensor. Here is photo of the ignition box components. I havent done much electronics so we'll see how this turns out ;-)

I messed up the programming tool assembling so I must get a new kit and the ignition box must wait.

Changing the cylinder head gasket. There is an intake preheater (part #102 141 02 44) which looks like this (other pics  2 ja 3). This device must be bad for intake air flow and it cuts down the flow area. The resistance is about 0.8 ohms so the heating power is about 180 W @ 12V and 230 W @ 13.5V. I wonder if it has to be there in the summer time / in the winter time / at all? I guess I'll leave it out and test the cold driving without it. (This part has not been on all MB 190 year models.)

Intake manifold / air preheater.

The sylincer head job is ready. Here are some pics from the front side, under side, intake side and exhaust side. The head was skimmed by 0.006" (0.15 mm). The valves and seats were ground and the exhaust bosses and all the boss rubber sealings were renewed by local machining shop.

Skimmed cylinder head.

The inlet valve size is 1 11/16" (43 mm) and the size of the inlet port is 1 9/16" (40 mm) at the surface and 1 1/2" (28 mm) about half an inch deeper and on the exhaust valve size is 1 17/32" (39 mm) and the port 1 29/64" (37 mm) and 1 11/32" (34 mm). The cylinder head is a typical cross flow head with hemispherical combustion chambers.

The cam timing may have been one tooth early which would mean 20 degrees on the crankshaft. Now it is about 4 degrees lake on the crankshaft. Hope this will make the engine run a little better.

Finally got the car running again. Had a little trouble with the chain tensioner sealing which let a lot of oil out at start up. The engine seems to start and warm up OK despite the missing preheater in the intake manifold.

The power is OK, but the knock is about the same. The ignition must be in the N position and I must watch the throttle. I'm still waiting for the aussie parts to get the ignition box programmed.

I put the intake air sensor back once again. Ran a quartermile in 15.88 and the speed was a little under 87 mph (140 km/h). This was the first 15 second run! 0-62 mph (1-100 km/h) took 7.88 seconds, so I'm on the right path! The knock came in the third gear so I had to back off the throttle. The engine stalls at 4700 rpm in third, too.

I tested the fuel pressure regulator with boost feed, but the mixture went leaner, not richer, in higher revs. The fuel pressures seem to be OK and the fuel distributor plunger has some shine marks on it but it moves freely in it's cylinder. It seems like the CIS-E doesn't like to have boost in the fuel distributor. The pressure in the upper side of the plunger makes the mixture weaker. The dilemma with the CIS-E is that lack of power can be caused by too low gas pressure or feed or too high fuel pressure.

I got the programmable ignition running but the joy didn't last for long. It worked for a few test drives and then went permanently in the silent mode. I cahanged a few transistors but it didn't help. I got no support from the seller's web site or forum. The next step will be to buy a MSD Boost Timing Masterin when I'm sure it works with Bosch EZL ignition.

I got a 2.5" stainless cat from USParts for a reasonable price. I bought a 2.5" stainless exhaust pipe from Martelius and had it welded to the cat at  Mankinen machine shop, where the customer service and the quality of the worj were very good. I went there on a Friday in July 12.30 in the afternoon and got the job back before 3 o'clock!

I changed the whole exhaust pipe to 2.5" with no silencers. I found a bad looking crack in the exhaust manifold. I must take the manifold off and have it welded.

After the Kalajoki FHRA nationals (just watching) I got a new intercooler from New Zealand. The core dimensions are length in flow direction 12.5" (320 mm), width 12" (300 mm) and thickness 3 1/8" (80 mm). I must drop the radiator lower to get the intercooler hoses to run over it.

The intercooler core.

From above.

From behind.

The operation manifold - exhaust pipe - intercooler - ignition box is almost ready. I adde a straight thru end silencer to the pipe. I ordered the Boost Timing Master from the U.S. on Saturday a week ago and it came to the customs mail last Tuesday. Delivery in a little over one week, not bad.

I took away the turbo manifold when putting the new intercooler in place. It has a long crack under the flange:

Here is the fixed manifold in place

The exhaust pipe is OK now and the Boost Timing Master is rady for test drives. The box seems to work and now strts the fine tuning with ignition timing and fuel mixtures. The auto gear box seems to slip when changing from first to second and from second to third. I'll try to moke the upshifts tighter by injusting the valve in the gear box. It is located in a real tight spot on the dreiver side of the 722.4 box.

I tightened the shifts by one full turn. The best run now is 15.29@93.7 mph (150.7 km/h). The temperature was around 43 degrees F (6 deg C). The electrical target lambda was 0.85 (AFR 12.5) and the actual mixture was between 0.76 and 0.90 (11.2 - 13.2) during the run. The final speed gives a theoretical 180 rwhp. Not bad for an 18 year old Mercedes!

Best run in the year 2008 in seconds and km/h

...and fuel mixtures and rpm