Damn, blast and bugger it

[flying farmer]

This was my grandads favorite saying when things went wrong, and I used this and a few more today!
Yesterdays run on the rolling road showed a drop of 15bhp from last year, obviously my modifications are going the wrong way as the Stag was already 15 bhp down on the TR.
As the rolling road was due to be there today, I set about my inlet trumpets last night, finally getting finished at 12.15 am
Unfortunately when I came to start the engine this morning, the knocking from cylinder no2 told me in no uncertain terms I had f####d up completely by letting a foreign object get down the inlet tract, despite plugging them with paper towel while I worked on it.
Several hours of poking and prodding with a variety of vacuum cleaners, compressed air, bits of wire and magnets failed to produce any bits of metal, so I had to whip the head off tonight.
This is what I found, I assume the bits of metal were a washer, but I haven't the foggiest idea where from, so now I have got to spend a day putting it all back together again, hope I have still got some inlet manifold gaskets in stock.

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[wilf]

Very, very bad luck.

But at least the piston and head don't look too bad.

[Andrew S]

The washer could be missing from the airbox at one time. I didnt believe they coudl be sucked in, but my friend did it and had the same

[Seaking]

Well on the bright side you now have a year to play again maybe make diffrent ones up so they can be bolted on at the show

[mjheathcote]

Bad luck there :-(It was fun on the RR on Saturday though :-)
I left just after midday today, with the rain in the morning don't think the RR was running.
Cheers
Mike

[KOY 23]

Hard luck, the only consolation is that you didn't have a wasted journey today, as the RR packed up after it rained.

John.

[StagManiac]

That's really rotten luck, Neil. I hope the damage is not so bad that you need to replace the piston and repair the cylinder head.

Paul

[StagnJag]

Sorry to hear that Neil, I was wondering why I didn't see you today.

Great to see your TR in the flesh as well, very nice.

Rgds

Dave

[Bob Heritage]

That's rotten luck Neil & thanks for all the entertainment by putting your cars on the RR Saturday ---probably one of the highlights of the weekend. As John said they didn't even get the covers off on Sunday and went home.

[flying farmer]

While the head was off I decided to look very carefully at the combustion chamber area in case I could learn anything useful when it comes to building the next high performance engine for my project stag.
The first thing I measured was the depth of carbon on the edges of the piston crown and head to determine wether I can skim more off the block to get the compression up, the answer being yes as there is over 14 thou of carbon present.
Secondly I noticed that the long duration cams need bigger clearances than I had allowed for. I had made cut outs in the pistons for the inlet valves but hadn't made the cut out quite wide enough, and I thought I had adequate clearance on the exhaust valves, but I could see where they had touched the carbon build up on the piston crowns. Things tend to stretch a bit at 6500rpm on the rolling road.
The application of a sharp wood chisel sorted the clearance problems, all high tech stuff!

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