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lynx
NurseHolliday
Got MX5 back. DRAMA.
I started getting concerned when the guy rang me to tell me he'd road-tested the car and checked the AFRs on his wideband. He said it was running ever so slightly rich but that's OK because it's safer (fine - I agree), but he said it felt slower than the other Jackson Racing supercharged cars he's built in the past, but he couldn't check if boost was low. I asked him why, as there's a perfectly usable boost gauge in the car, and it's running a smaller pulley than standard so it should feel quicker. He said it wasn't working, it was reading vacuum but not boost - I don't think this is possible, it either works or it doesn't.
Anyway, I went to pick it up, he turned it on, it was noticeably mechanically quieter than before, which was good. I completely forgot to query the boost issue as I had to quibble on the price and after getting £50 knocked off, I drove it away. First things I noticed were that it was fucking filthy inside, it had sat for 5 months on my driveway and stayed tip top inside, it was now mouldy in many places, my suede OMP steering wheel had dirt marks and was matted in places, and the passenger seat had a stain on it (luckily that brushed out).
I could tell that it had a boost leak, I took it easy until it was nice and warm then tested a bit of WOT and the boost gauge swung straight up to 0, and as the revs built there was a massive whooshing sound - much like a quieter version of a screamer pipe- and the gauge stuck dead on 0 until I let off when it swung back down and resumed measuring vacuum.
I needed it this weekend to go to Scunthorpe and back so I cleaned it up inside, and I thought I can still drive it without boost, the Bipes/RRFPR are reactive, so if they don't measure boost, they won't adjust timing or fueling so it will just drive like an NA but with some power loss due to turning the supercharger. It still feels quick, 3/4 as fast as before, which suggests to me the head work is more than I expected, and with boost it will be quicker than before.
However, it's been 425 miles since I got it back and it's consumed 1 litre of oil. I can't chalk that up to running in a new head, there's no visible oil burning smoke, no smell of oil burning, no oil stains on the floor, it's doing something to that oil... Water is the same level, no mayo in the head or on the cap, I'm going to take it back but I'm now worried the bottom end is fucked too.