355 Exhaust Bypass valve

[Reggie20]

Just a heads up for 355 owners. I had an issue with the exhaust bypass valve not opening or only partially opening. I didn't realise but it is a common problem on these cars. I decided to purchase a Capristo bypass valve for about £450 ish. I took it to Rardley's for its annual service, mot and for them to fit the valve - no problems at all for them to fit the valve. When they took the old one of it was completely knackered - amazed it even half opened. We looked at the price of a geniune Ferrari bypass valve - £4,200😳 - could believe it and an inferior quality product. I know there is a 'Ferrari tax ' that we pay but 10 times an aftermarket price is crazy IMHO!

[Gassmi]

Yep, the stock 355 exhaust valve is known to seize or fail internally. £4,200 from Ferrari is a joke. Capristo is the smart fix better made, works properly, and a fraction of the price. You did the right thing.

[HardtopManual]

Where'd you get one that cheap Reggie? Last time I looked they were nearer a grand.

[Reggie20]

Hi Charlie,
I got it from Scuderia car parts. In fairness I've looked at the invoice in more detail - it was £780 but they owed me a credit of £350 from a previous order hence the £430 ish cost. Sorry if original post was misleading.
Still great value compared to the original at £4.2k!

[Thom]

The membrane in the actuator had sheared on mine, all it took was to purchase a 60€ actuator off Ebay to fix it, along with elbow greasing the ball joints with WD40 to loosen up the movement as exhaust soot gets in there over time. The price of the Capristo valve is a joke. There is hardly any more standard ish exhaust item than such vacuum operated exhaust valves.

[HardtopManual]

I've replaced the actuator in mine too, with a porsche part costing fifty quid. But I could really do with a new valve to sort the startup rattle. I assume it's just a standard 2.5" vacuum valve with a good quality one costing £150 or so, but not got round to finding out yet.

I think the cars are getting to a price point where there are fewer DIY jobs being done on them "to maintain the value" and the body of knowledge on parts interchangeability has plateaued.