I am SOOOOO Tempted

Wack61

Wack61

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Nothing because who would need them, man maths says buy them, fit them then remove when you sell and they're free
 
CatmanV2

CatmanV2

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Need to sort out a couple of things (like a working bloody car), but if they are still there in about 10 days....

How is the vacuum 'delivered' on the GTS? I can't see anything in the parts diagram.

Which would mean, at least at first, they'd be open all the time......

C
 
CatmanV2

CatmanV2

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Contigo said:
Do it! Vacuum is delivered from Inlet manifold pressure. I'm sure there's a way!
Click to expand...

It's not actually. Just managed to find it from the Stardale diagrams. It comes from the secondary air system vacuum bottle. I wonder if using just manifold pressure would actually result in the valves having less vacuum on them at WOT?

Perhaps a little electric pump?

Phil is the kind of stuff Josh gets into?

C
 
Contigo

Contigo

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Interesting, I wonder if Strad is different, remember there are two modes where valves are RpM dependent in Sport mode but fully open in Race. You checked the GTS drawings?

Josh might be able to help
 
CatmanV2

CatmanV2

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Contigo said:
Interesting, I wonder if Strad is different, remember there are two modes where valves are RpM dependent in Sport mode but fully open in Race. You checked the GTS drawings?

Josh might be able to help
Click to expand...

I can't see any difference in the systems on the GTS, Eurospares don't even show the boxes as valved as far as I can tell (although I've not checked every variant they list, just the obvious 4.7 F1) A little 12v pump should be able to do it anyway I'd have thought.


Ahh worked it out. Yes the GTS has the same vacuum bottle as the strad. Different from the 4.2

C
 
CatmanV2

CatmanV2

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This also explains why it takes so long for them to go quiet. From the descriptions, I was expecting a quick bark (like about 1 second) until vacuum built up in the manifold and closed the valves. When Miles started up (ooer) outside, it was more like 5+ seconds before it went quiet. Clearly vacuum building in the bottle.

C
 
drewf

drewf

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CatmanV2 said:
This also explains why it takes so long for them to go quiet. From the descriptions, I was expecting a quick bark (like about 1 second) until vacuum built up in the manifold and closed the valves. When Miles started up (ooer) outside, it was more like 5+ seconds before it went quiet. Clearly vacuum building in the bottle.

C
Click to expand...

Only Maserati could turn a piece of poor engineering into an alleged sales plus-point! :D
 
Ryandoc

Ryandoc

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1,850
Vacuum for both sides goes via a single solenoid valve that is located on the right hand side silencer, confirmed to me I'd week.
 
drewf

drewf

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Contigo said:
I'm not sure our neighbours agree :D
Click to expand...

Exactly! Plenty of people on here would like to be able to have a quiet start at home in the early hours, unleashing the proper noise when not on your own doorstep. I'd assumed it was noisy on start by Italian design rather than just a ****-poor piece of engineering :D
 
CatmanV2

CatmanV2

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So if they are still around when I get the car back, and we're back from Rome, this may well be my bonus present. I think a vacuum pump and remote actuator in the boot should be simplish.

And that should let it be quiet in the mornings....

C
 
drewf

drewf

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CatmanV2 said:
So if they are still around when I get the car back, and we're back from Rome, this may well be my bonus present. I think a vacuum pump and remote actuator in the boot should be simplish.

And that should let it be quiet in the mornings....

C
Click to expand...

Very easy to sort that setup - trigger the pump using the door unlock signals?
 
CatmanV2

CatmanV2

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drewf said:
Very easy to sort that setup - trigger the pump using the door unlock signals?
Click to expand...

Now there's a thought. I was simply going to use one of those cheapo kits from ebay (per my remote boot on the 4200) so I can select loud and sport separately.

C
 
CatmanV2

CatmanV2

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Contigo

Contigo

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drewf said:
Exactly! Plenty of people on here would like to be able to have a quiet start at home in the early hours, unleashing the proper noise when not on your own doorstep. I'd assumed it was noisy on start by Italian design rather than just a ****-poor piece of engineering :D
Click to expand...

I think even manifold systems will still be loud for a split second until pressure is reached and the vacuum closes the Valves!
 
CatmanV2

CatmanV2

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Contigo said:
I think even manifold systems will still be loud for a split second until pressure is reached and the vacuum closes the Valves!
Click to expand...

Totally agree. But my pump would build vacuum almost instantly and would also be triggered on ignition on, not engine start.

I guess I should worry what the duty cycle of those pumps is.

C
 
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