Friday, November 9, 2012

Ferrari Sales San Francisco - Ferrari F355 Buyers Guide - San Francisco Motorsports San Rafael

 Ferrari F355 Buyers Guide


With 1009 bhp per litre, the F355 engine had the highest specific output per litre of all normally aspirated production cars when it was first manufactured.  With a full 8,500 revs available it's a hoot.  Service it regularly and it will deliver with suprising reliability. Here's what to watch out for.

Rattling Bypass Valvle

The F355 has a system for controlling the exhaust output through the use of something known as a bypass valve.  The bypass valve opens up at higher RPM, allowing the exhaust gases to take a more direct route to the tail pipes, thus increasing power and noise.

This means your 355 is quiet around town but when you open it up it screams somewhat.  The benefits of the bypass valve are less if you have an aftermarket exhaust fitted, because even the low RPM sounds with the valve closed will be louder.

Over time, the bypass valves seem to wear and eventually they begin to rattle when the car is idling. There are a few solutions to this:

  • Put up with it, and do nothing. This is by far the cheapest solution.
  • Replace the valve with a new one. They new one will wear again.
  • Replace the valve with a straight tube (no bypass). This increases idle noise levels.
  • Wire the valve open.  If you wrap some strong wire around the valve to hold it in the open position, you will stop the rattle but increase idle noise levels.
  • You may be able to find a that does an aftermarket bypass valve.
Cracked Manifolds

This is a very common issue and every car will suffer from it eventually. The problem lies in the design of the manifold. When constructed, the tubing is bent to the point that i becomes relatively thin, and with the manifolds running at a very high temperature the metal eventually cracks.  This results in a ticking sound at idle and if you put your hand inside the engine bay you may even be able to feel the air compressions that result from the leak.

This problem can be sorted in three ways:

  • You can get a new manifold from Ferrari. I would not recommend this option because this is a design fault and Ferrari have not redesigned the part. Therefore it will fail again and with manifolds being around $3,500 per side this is not cost effective.
  • You can buy an aftermarket manifold. Tubi does one but it is very expensive. 
  • You can get you exisiting manifolds reconditioned.
Removal of the manifolds can be a reasonable job or a fairly big job, depending upon the side that has failed.  Looking from the rear of the engine, at the right side there is an oil tank (the car is dry sump) whic must first be removed before the right manifold can be removed.  This adds a few hous to the job.  The left side can be removed more easily.  The right side will go first.

Electronic Suspension

The electronic suspension has two settings - sport and comfort mode - and these are controlled by the use of electronic shock absorbers.  At the top of each shock is an actuator that cntrols the stiffness of the shock.  These have been know to fail and can be relatively easily replaced.  If there is a problem with the electronic suspension, there is a warning lamp that will light up on the dashboard.  It will come on at ignition time but should go out shortly afterwards under normal operation.

Heater Valve

The heating system operates via an electronic valve that moves to allow hot water through the heater matrix across which air is blown to warm it up.  There are a couple of possible reasons for failure. - either the aircon ECU has failed, which controls the position of the heater valve, or the motor on the heater valve itself has failed.

Sticky Throttle Pedal

Most cars suffer from a problem whereby the throttle seems to resist your foot pressure at the top, of the pedal travel. this tends to make it a little tricky to drive slowly in traffic until you get used to it.  The early cars had a slightly different throttle mechanism and these can be upgraded with the newer parts (there is a quadrant on the throttle cable that was updated). However the problem was never fully corrected by Ferrari, so most specialists when they service the vehicle lubricate the throttle to help with the issue.  After lubrication the behavior is always improved but id doesn't usually last until the next service. 

Valve Guides

The truth is that if it happens it is very expensive, but only a small percentage of cars have actually experienced the problem and most of those did so fairly early in their life.  There is no guarantee by a later car (97 or 98) is much less likely to experience the fault.

The first cars built used bronze valve guides, and these very soft guides tend to wear too easily.  Once worn the guides allow oil to leak past them and this results in the engine burning oil.  Left unchecked, the oil will eventually run low resulting in significant engine damage.  The results of a compression test can give you an indication as to the condition of the engine in respect.

Later cars had their valve guides changed to steel.  It is not possible to tell which guides your car has just by lookin gat the build year or registration number, because Ferrari seemed to use both materials for a while. To find out, get the car's chassis and engine number, and query Ferrari eith through a dealer or directly. 


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