Compared to the recent bout of doom and despondency, this post should turn out to be slightly more upbeat.
First up I took the remains of the shattered exhaust over to Andy’s and we welded in a new cat, as seen here. (I really need to get a TIG welder…) Apparently, the cat I had is one of the earliest batch produced by the company that Andy got them from and they now weld the cat canister into the housing. (If you look hard at the photo you can see where there’s some grinding on the top of the housing, this appears to be the end result of where a hole has been drilled through the housing and then filled with weld material after the cat was inserted.)
This was done because, they say, the original cats had a tendency to move in the housing. It’s just possible that this is what happened to mine, but I’m not convinced. However, it was enough to convince me to just put the cat back in the same place and have another go. What’s more, the suppliers have provided the new cat for free, although they want the remains back.
The photo here shows the cat when looking up the silencer. Contrast this with this before photo and you can see the difference. Whether it stays like this in anyone’s guess.
To try and help it along I’ve booked a day at a rolling road dyno. The people at PDQ come highly recommended by Andy as well some other RGBers, so I’ll take the car there and make sure that the fuelling is good before trying to roast this new cat.
With that done, I’ve repacked the silencer. The wadding that was in the silencer when it arrived from Tony Law was the loose glass fibre stuff. I’ve replaced it with the sheet wadding, as in the photo on the right. This is rather more expensive than the loose stuff but, in my opinion is far superior because:
- it doesn’t irritate my skin; the glass stuff leaves me itching for weeks,
- you can just roll it around the central tube as in the photo and
- it’s much easier to get it packed to a consistent density; it just depends how hard you lean on it as you roll it up.
So that’s now back in and the headers are re-attached on the car. I am, though, going to have to move the exhaust mounting slightly. The way the new cat has been welded in has meant the silencer has moved back by a few millimetres. What’s more, we didn’t quite get the headers/cat/silencer lined up properly so the silencer is in a slightly different position. All I need to do, though is to weld a slightly different tab onto the exhaust mounting.
I’ve also started doing a couple of other things. The oil temperature was slightly too high at the Snetterton test in that it was up at around 120° (the water actually got to nearly 90° as well). This really means that I’m going to have to do what I always meant to do and refit the oil cooler. So, as discussed before, I’m refitting the sandwich plate that I used on the 919 engine. I need to modify the hoses slightly though and I’m in the process of working out how best to do that.