What damage does it do?

[chassis 33]

Does anyone know what damage, if any, running at fuel pressures in excess of 60psi does to the injectors?

I know it doesn't help the injectors open and limits fuel supply, but does it actually damage them?

Regards
Iain

[Ballistic Banana]

I'm trying to remember now, MA showed me a standard Injector which someone had taken appart for him.
Doesnt the fuel push a plate that at the end of the injector that makes the spray pattern, I can imagine that it could push the plate too far and make it stick!!! Just thinking aloud and it probably wont do a thing.

Interested to see the pros replys

edited to add I think that plate also has tiny holes in it that the extra pressure may have negative effect with? Can still only see any damage if any being the plate being pushed too far and sticking.

BB

>> Edited by Ballistic Banana on Friday 12th May 00:01

[chassis 33]

Cheers, thats vaugely comforting. Needless to say I'm going to be donning my toe caps and kicking the muppet who did it at first light.

Regards
Iain

[david beer]

Interesting ! does that involve squeezing the regs case ? and if so do the injectors leak and cause poor starting when hot ?? ie cranking for 30 seconds before it will fire.

[tahiti450]

chassis 33 said:

Does anyone know what damage, if any, running at fuel pressures in excess of 60psi does to the injectors? I know it doesn't help the injectors open and limits fuel supply, but does it actually damage them? Regards Iain

Its unlikely to do amy actual damage to the injector, fuel pressures can vary quite widely depending on the application though around 38-40 psi is typical. The problem is that - assuming the pressure hasnt been raised for a specific reason - the engine will be running very rich if the pressure is too high.
The injection system measures the rate of air consumption and load - via the AFM, ECU and engine speed, and calculates the injector opening time required to deliver exactly the correct amount of fuel to provide optimal combustion and low emissions with this being trimmed by temperature sensors. However the correct amount of fuel being delivered during the open-time depends entirely on the correct pressure in the fuel rail. Raising fuel pressure is a commonly used and very crude method of increasing fuelling on modified engines, and may provide decent fuelling for wide open throttle conditions where the engines air flow is outside the fuelling map in the ECU, but will then deliver too much fuel under all other conditions, so high emissions , poor economy, plug foulling and poor part throttle performance, so really this is in the realms of the bodgers approach to tuning. If the car has cats then the lambda sensor system would try to compensate for the low exhaust oxygen levels produced by over rich mixture but the amount to which they can compensate is i believe fairly limited and unlikely to correct gross fuelling errors.

dont know if that helps?
Alan.