Wastgate

The original wastegate was in quite rough condition. It needed quite a bit of work, although we managed to save it.

The valve seat was recut, a crack welded up, and the old bolts removed. I used stainless bolts now, to prevent rust seizure.

Heat distorted the mating surface. 

I skimmed it by hand.

Assembling the unit was a bit tricky, but with the right tools, nothing is impossible :-).

Engine assembly 8.

Okey, this was the hard chapter of the engine building. We bought this nice stainless steel exhaust system. A piece of art it looked... a nightmare to install it proved to be...

The exhaust port diameter was 38mms, which is a nice number, equals to 1.5inches. Unfortunately the pipes on the new exhaust had 40mm outer diameter. Culture clash :-(. The ports had to be enlarged in situation, with the greatest care not to get metal dust into the engine. A pain in the back. After enlarging the ports, we had to redrill all the six holes in the flanges, as they were slightly off-centered. Nice... 

Note the plugs in the air injection holes.

New problem... the mating surfaces were not skimmed after welding. The heat distorted and made the surface concave by 1mm :-o. 

I skimmed them :-/... and all the other couplings...

Finally I bolted the whole together, just to find out, that the curves are not correct, thus the turbo is not at its correct situation

At this point, I intended to set fire on the whole stuff, but a young Jedi appeared in the last moment and saved the day.

I took off the turbo support plate and altered its shape. Giving the final "touches" in situation. I am affraid, that the Muffler will also need a bit of modification :-(.

Engine Assembly 7.

With the carefully selected parts, the top of the engine was ready to bolt together. Here I applied a bit of sealing compound, and later some anti seize lube on the bolts, before torquing down the head bolts.

We had some problems while installing the rocker shafts. Even with extra care, the rubber o rings were cut by the edge of the casting. 

Te original rubber has square-edges.

I modified them and turned one edge down a bit. It was much easier to install them. 

Measuring the timing gear line-up was a two man job... I mean actually a one woman-and-a-man job. My one-and-only did the job perfectly. 

With the original shims modified a bit, the miss-alignment is now under 0.05mms

Setting the cam timing with 0.1mms valve gap. Note the "professional" chain tensioners :-).

New camshaft tensioner oil feeds installed. They came with blue zink plating. How ugly :-P...

... I had to replate them.

After double checking the cam timing I set the valve gaps one-by-one. 

New oil cooler.

Engine assembly 6.

Just as the heads came back from the machinist. They had some cracks repaired, studs and air injection removed (it will now be blanked), seats recut and new exhaust guides installed. I was completely satisfied with the work.

Still I checked the clearances, just to see everything in order.

As the seats were recut, the springs had to be repacked. As the new seat is now more deep in the head, we will need to add shims and the set we had from the original engine will not be enough. I prefer to take

measurements with the springs installed. By measuring the distance from the top of the spring disk to the valve cap and adding 2.8mms, You can compare it to the factory data od 33.5 +/-0.3 mms. Nice half day game to get it all sorted.

Engine assembly 5.

Although the original barrels were reusable, we went for new parts for perfection. Many people will tell You to put the parts straight on just as they came out of the box, I would argue with this.

The very first piston came out like this: ring gaps at the same location. This would result oil loss and possibly compression loss.

Although came from the factory in sealed boxes, they were quite a bit dirty. And this type of dirt is evil: machining debris.

As You can see on the edge of this pipe cleaner: alloy dust.

After cleaning, I made a through measurement on the rings, and gaps, piston clearances. This time I was happy to see everything in order.

After fitting the cylinders, I checked the deck heights and counted the compression ratio.

With a preloved crank, and cylinder heads, it is mandatory to check if they make one flat surface before bolting the camshaft housing on, as otherwise the cam will get stucked. Interchanging the heads with some patience, You can come out with an acceptable combination.

Engine assembly 4.

Cleaning the crank with alcohol.

Some assembly lube on the bearings.

Applying and spreading the sealing compound.

When torqued, it should look like this. I hope it is as even as I intended, otherwise I will be in great trouble.

Fitting the cylinder head studs. This time they came from ARP.

Oil thermostat and breather.

I use a very special tool (my mobile) here as the dry fitted oil pressure piston did not wanted to come out. Dont fit anything dry.

Finally the flywheel goes on. Although the pilot bearing was in good condition, I replaced it as it is cheap and now easy to get access. Unlike when in the car... 

Engine assembly 3.

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