metropower.info

so I have had this car for a really long time and most of you have probably seen it. First I will start with a short description of the history of this car

I got the car in 2005 and at that point we renovated the car, fixed a large dent in the front, fitted it with fibreglass turbo wing extension and and had it painted. It was a really cool looking car and I used it as my daily for 100k miles. when I stopped using it as my daily I started using it for historic hill climb racing in denmark.



the car has been upgraded several times along the way with things like 1.5 rockers and maniflow exhaust system, dual carbs and a ported cylinderhead.



working with this car is really exciting and I learn something new each year. and many parts have been broken along the way:)









this was how the car looked for a really long time

dual brake boosters, adjustable proportioning valve, braided brake hoses and cooper s 1 inch spaced drummes.

a few racing pictures









but I do spent most of the time doing these kinds of things with the car

in the 2016 season the car had a lot of breakdowns unfortunately so this gave me lots and lots of quality time working on the car

lots of broken headgaskets, a broken clutch pressure plate, clutch stuck on the flywheel etc.

started fixing the engine for racing this season. I had a new engine block prepared by a machine shop and fitted the pistons, conrods and crank from the old block. I then measured and calculated the compression as I was aiming to lower the static compression to 12:1, took the whole thing apart again and had a bit of material machined off the top of the pistons.

Machining the top of the pistons together with using a standard block that had not been resurfaced gave me the desired compression.

I decided to lap in the valves as this hadn't been done in a while and I found out that they needed it, especially the exhaust valves, so I started doing this. while doing this I found out that the valves again especially the exhaust valves was worn where they meet the seats so they needed to have the angle recut so I started doing this, I also found out that some of the valve guides was too worn, so I changed the guides. after fitting the new guides I found out that two of the valves did not fit through their guides so I bought a 7-7,75 mm reamer which I used to open up the guides just enough for the valves to move freely in their guide.

The head is not done yet but when I finish cutting the two last exhaust valves I will start lapping the valves in again. Hopefully the seats wont also need cutting.

I wonder why the exhausts wear so much more than the inlets and why their mating surfaces were black unlike the inlet valves. The exhaust valves also seem to be made from a harder material than the inlets.

DotMatrix wrote: ↑Tue Apr 11, 2017 9:47 pm
I wonder why the exhausts wear so much more than the inlets and why their mating surfaces were black unlike the inlet valves. The exhaust valves also seem to be made from a harder material than the inlets.

That's an easy one, cold, fuel damp air going in, rather hotter combustion gases going out.

Artstu wrote: ↑Wed Apr 12, 2017 7:02 pm

DotMatrix wrote: ↑Tue Apr 11, 2017 9:47 pm
I wonder why the exhausts wear so much more than the inlets and why their mating surfaces were black unlike the inlet valves. The exhaust valves also seem to be made from a harder material than the inlets.

That's an easy one, cold, fuel damp air going in, rather hotter combustion gases going out.

thanks. that must of course be the reason

why is my inlet valve seats more worn and pitted than the outlet seats then? they were all put in at the same time.

the engine is now back in the car and running reasonably but not 100% adjusted yet. I have booked a time at a rolling road but unfortunately they don't have time for another 14 days, so I will miss the first race, but then I will have enough time to adjust, measure and check everything to make sure its right. I really hope it doesn't break this year!

so the last week or two was a very busy one with work on this car!

I finished assembling the engine, fitted it to the car, adjusted the timing and carburettors and fired it up. I immediately noticed that it was lacking power, I checked everything and rechecked it but couldn't understand that the cam timing was 6 degrees out but the key and wheels was fitted correctly. this turned out to be chain stretch even though the chain is only 2-3 years old and is a duplex chain of a decent quality.

As I have recently bought some spares from KLAS off here which included a adjustable Slark race engineering cam drive set using gears instead of a chain I fitted this and adjusted it which took some time but it ended up being correctly adjusted.

By the way checking and adjusting the cam timing without removing the engine from the car is doable but not easy or comfortable.