Disco 1 Snake oil?

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As said by @brian47

The technical description seemed a little bit like someone reading a script from a Star trek episode. not like someone stating what they knew as facts.

Cheers
 
why doesent just advance the pump to optimum, advance is used as fuel has one burn rate, over advance wont help and create knock and loss of power and severe engine strain
 
Be interesting to hear from someone who has actually done the mod, BUT two things I noticed straight away
1, add 3 washers that he called shims of appros 1mm thickness = 3mm
2, add the alloy spacer of approx 3mm thickness = 3mm
So what has he actually achieved by moving the cap out 3mm then adding 3mm of shims to put the spring back in the exact same place and load?
 
Just read this and still none the wiser?

Injection-timing Advance

At the bottom of the injection pump is the automatic-advance timing device. As fuel-supply pump pressure increases, the piston moves the roller ring opposite to drive shaft rotation, advancing injection timing, Figure 22. As engine speed increases, fuel pressure from the vne pump also increases. This allows the timer piston to overcome thetimer spring, causing the roller housing to move opposite cam-plate rotation. The rollers then engage the cam-plate high points earlier, advancing injection timing.
 
this is similer to the VE fuel pump you can wind in the ratchet system allowing to the boost pin to open greater = more fuel
basically this vid he is shimming up the spring tension just allowing more fuel to enter under boost ..this doesn't advance or retard any timing ..it apprars to be some sort of pressure regulator so probly increasing the pressure in the fuel rack inside the fuel pump adjusting the crack pressure to each injector

over time springs do become week

also what I cant understand he says you want to advance the timing early in the vid ..at the end of the vid he then goes on to mention less shims increase the timing ..

so why did he add shims ? if removing shims is better basically what he is saying some injectors have different crack off pressures to another wear and tear age etc

just like the Td5
the high pressure fuel pump maybe working 100% but if the fuel pressure regulator is week ie lost its spring tension engine performance will suffer
the reason he is monitering fuel pump pressure with a gauge installed behind the fuel pump in the vid
 
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lynall said:
Be interesting to hear from someone who has actually done the mod, BUT two things I noticed straight away
1, add 3 washers that he called shims of appros 1mm thickness = 3mm
2, add the alloy spacer of approx 3mm thickness = 3mm
So what has he actually achieved by moving the cap out 3mm then adding 3mm of shims to put the spring back in the exact same place and load?
Click to expand...

Increased the stroke of the timing device piston. This will give more advance at higher RPM and internal fuel pressure.
 
ozzyboydeano said:
this is similer to the VE fuel pump you can wind in the ratchet system allowing to the boost pin to open greater = more fuel
basically this vid he is shimming up the spring tension just allowing more fuel to enter under boost ..this doesn't advance or retard any timing ..it apprars to be some sort of pressure regulator so probly increasing the pressure in the fuel rack adjusting the crack pressure

over time springs do become week

iam just wondering the pressure gauge install behind the fuel pump I'm guessing he maybe adjusting fuel pump pressures

also what I cant understand he says you want to advance the timing early in the vid ..at the end of the vid he then goes on to mention less shims increase the timing ..

so why did he add shims ? if removing shims is better basically what he is saying some injectors have different crack off pressures to another wear and tear age etc

just like the Td5
the high pressure fuel pump maybe working 100% but if the fuel pressure regulator is week ie lost its spring tension engine performance will suffer
the reason he is monitering fuel pump pressure with a gauge installed behind the fuel pump in the vid
Click to expand...

No he isn't, he is leaving the spring pressures as they were and increasing the stroke of the timing device piston by moving the stop out the thickness of the new ring. This will give more advance at higher RPM and internal fuel pressure because the static cam can move further round advancing injection. It does not increase fuel in any way.
 
wammers said:
No he isn't, he is leaving the spring pressures as they were and increasing the stroke of the timing device piston by moving the stop out the thickness of the new ring. This will give more advance at higher RPM and internal fuel pressure because the static cam can move further round advancing injection. It does not increase fuel in any way.
Click to expand...

internal fuel pressure ?

the timing of the pump has not changed maybe the boost ring is a fuel pressure boost ring and maybe the name on the packet needs to be adjusted instead of boost ring

because the injectors don't have a electronic solenoid
the injectors work off crack pressures delivered by the fuel pump ..so basically he is adjusting fuel pump pressures ..this can infact make an injector squirt earlier due to seing a higher pressure earlier up in the higher rpm range as the fuel pump is creating more pressure the faster it turns

and said that
that's why he may offer different shims compared to another maybe because there injectors don't have the same crack pressure to another vehicle due to injector age etc


 
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ozzyboydeano said:
internal fuel pressure ?

the timing of the pump has not changed maybe the boost ring is a fuel pressure boost ring

Click to expand...


Don't think you understand how the dynamic timing device works. As the pump turns faster more internal pressure is generated, this can vary subject to RPM from around 3.5 bar to 4.5 bar. As internal fuel pressure rises the timing device piston is pushed against the spring pressure which rotates the static cam to advance the point of injection. All that is being done with this mod is increasing the stroke of the timing device piston by moving the stop out the thickness of the new spacer ring. Original spring pressure is retained by adding the shims. But the piston has slightly more travel and therefore turns the static cam slightly more to advance the point of injection. The amount of injected fuel does not change but the point of injection does.
 
no but I learn new things every day and the only way to test this would be a dyno or a pyro gauge
and how much noticeable is it
 
The Mad Hat Man said:
Are we saying this is a good thing, a bad thing, or a waste of time n effort?
Click to expand...
I have played with these pumps before on cars I have owned I have never messed around by adding shims etc
the one in the vid is similer to my old d1
still has the mushroom type valve on the top there is a air line that runs to the top of this this is the boost pin ..there is a ratchet type system underneath the diapghram I wound mine in a 1 turn it made a difference under boost
little I knew I had dribbly injectors and they came back as a fail ..my fuel injection guy said to me don't use them as this may damage your engine

my d1 is still sitting out side my house as we speak wrecked engine

I changed the fuel pump settings while using week injectors dribbly injectors
to a point I had a ocasianail blue flame out the exhaust when the engine was used heavily

I have learned from past experience make sure the injectors are working fine have them tested before playing with fuel pumps
 
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