KitNet track day at Castle Combe

[James Doulton]

I went to the KitNet track day at Castle Combe today in my Legerra. It was cracking weather and I had a good day. There were positives and some negatives. So starting with then the positives: My new tyres performed well and took 5 seconds off my lap times (down to 1m 35sec), I finally got the Legerra over the ton at 100.3mph on the straight, I met a load of nice chaps and did a lot of chatting plus, to round off the day, I drove it home at the end of the day. Two of the chaps were Duttons - but don't ask me their first names because I don't remember.

I spent all day yesterday preparing the car for today. I didn't manage to finish fitting my new seats so I had to revert back to the old ones. The new ones hold me better so I wouldn't have to brace myself in corners as I do now. With all of the extra grip from the tyres (Toyo Proxes R888R's) then the steering forces were quite a bit higher and it was quite a workout.

They say that racing improves the breed but it only served to find weaknesses today. I lost 2 of the bolts off my alternator, so had to grovel around under the hot and oily car. Luckily the organiser had a good selection of bolts in his support vehicle. (In the background of the picture you can see the Dutton brothers putting the remains of their car back on their trailer after hitting the tyre wall at Quarry)

I also had to remove the windscreen wipers because the wind was blowing them across the screen.

I had part of the brake light switch break off.

I also had a heater hose come off when I parked up, so I had to get the jack out again to remove the front wheel to get at it.

My day finished a little early when the car developed a 'misfire' which doesn't appear to be an electrical problem. So it now sounds like a Subaru. The 'misfire' didn't just happen, or I would have noticed the change, it just developed. I rather fancy that it got a little worse on the drive home.

It could have been worse: early on in the day I managed to get 3rd instead of 5th on the straight and saw the rev-counter returning from over 7000 rpm. That could have been a bit of a mess but it survived. I also found that I had to watch the revs because it didn't feel like it needed to change up until over 6500 (yes, that happened a few times).

So, overall it was a good day. I enjoyed the driving, the mechanic-ing and the racing. And I enjoy having the aches, up to a point. I am a bit concerned that my 'misfire' might be something more serious but that'll give me something to do over the winter.

[Paul Sheridan]

Or go the whole hog and fit a set of ...... Tritainium octagonal section springs :-)

[James Doulton]

I shan't even think about double valve springs ... damn, I just did!

[James Doulton]

Yes please Ade, if you have a set of valves that'd be good. I suppose I'll need to get the high-lift springs elsewhere?

[James Doulton]

The valve springs are Burtons replacement springs to go with the high lift cam. They allow the spring to compress further before binding, so may actually be weaker. Although it did go to higher revs earlier in the day, I had got better at watching the needle and was changing up at only 6500. But with higher lift and the higher acceleration needed to achieve that, then maybe they float at lower speed. It is a pity because it sounds so good at 6500! Yes, track days certainly find the weaknesses. I'll have to get a rev-limiter.

[Adrian Southgate]

Ouch.

I'll get them gaskets posted tomorrow. My I assume you no longer require a bottom end set and would you like a set of valves instead? 

[Big Vern]

The only way that the follower could 'get out' like that is over revving. If they are stock valves and springs then 6500 is a maximum. IIRC valve float is around 7200 and Pinto's will spit the followers out when the valve float and once the followers get out they can mash up the other parts too. Whats wrong with number? valve bent I should think. If its been revved high enough to dislodge the followers the I;d want to replace the valves and springs too. An unfortunate side effect of track days LOL. Remember a stock pinto make peak power below 6000 so sounds like you already had problems before then. Has it jumped a tooth on the belt as well?

[Paul Sheridan]

Possibly the retaining springs shook off due to valve bounce from over revving!  Just a guess.   Doesn't look like anything has over heated. 

[James Doulton]

This is the underside of the head with cylinder 4 to the right of the picture. That cylinder had no valve openings for about 20 miles of driving, so I'm not surprised that it looks different from the others. Its valves look fine. It is 2 and 3 that are now in question. Why was 3 so low? I can't see any reason yet - I'll go and get its valves out in a mo.

[James Doulton]

So this is why cylinder 4 had such low compression. This picture was taken exactly how I found it after the cam cover was lifted off. Any ideas for how the follower can get free like that?

[James Doulton]

Thanks for letting me know - it worked for me, presumably because I'm a member of KitNet. I have already downloaded them into my pictures so here they are ...