Thought I had taken pics of everything during dismantling!
Can't work out where the vacuum hose on the dizzy vacuum advance unit connects to at the other end?
I think it goes to a connector under the intake manifold, but I'll be damned if I can find it.
Advice most welcome!

Quentin

 

It appears to go to the vacuum regulator (#8), but I cannot find it!

 

Hi Mozambique

You can do away with most of that Stuff

 

Hey,
thanks!
I did come across that video. For now I just want to put it back together as it was. Can then ponder deleting parts going forwards.
So still trying to determine where it should go to?

 

It depends on what market the car was built to, for example the Canadian/US cars actually have a much simpler (and very different) vacuum system than the European cars. On a Canadian car, the vacuum advance connects to the dump valve which is located toward the right side cam cover, near the front.

 

It's a Canadian car so that sounds right. Quick search and it appears to look like below and I gather is bolted to the right side thermostat housing? Car not parked at home, so can't go and check. Not sure the hose would extend that far?

 

I'm pretty sure that is where the vac advance goes. It might go through the vac regulator, which I think is under the intake manifold. That photo is definitely the dump valve.

As an aside if your fuel use goes up by about 25%, you have a faulty dump valve and you are getting no vacuum advance.

 

Thanks!
Will be having another go at finding the connector today (pic above was off google)

 

Well it doesnt go directly to the dump valve as the hose is too short. Cannot see any T connectors lacking a hose that it might connect to enroute to the dump valve either.
Bit flummoxed!

 

FWIW, if you don't have to worry about emissions, straight manifold vacuum will give the best fuel economy and performance.

Doug

 

I can take some pics of mine if you haven't figured it out yet. Let me know.

 

Part of the reason for the V12's complicated vacuum system was to give a stable idle, and just off idle performance. With the AC on, straight manifold vacuum can give rise to stalling just off idle, as the advance goes from nothing to maximum as soon as the throttle plates are off idle.

A lean burn engine ( which the HE engine is) reacts differently to ignition advance than a rich burn. For a rich burn, I would agree with you, the HE is a different beast though.

 

Think I worked it out!
My system should look like this:


All the bits seem to be there, but the T connector off the vacuum regulator has been replaced by a simple 2-way connector (not OEM, marked in red). So the vacuum adv capsule was Not connected!



Does that make any logical sense. Off to get a T connector so I can reconnect it.

 

The advance goes from maximum to something less when throttle plates start to open. It doesn't instantaneously drop to zero, unless you have funky can

A diff vac can can fix stumbling problems.

Select a vac can based on your manifold vac at idle and pick a can that is fully open an no less that 2" vac below that. Use the 2" rule

The Two-Inch Rule states that the VAC must provide full vacuum advance at no less than 2" Hg less than idle speed manifold vacuum. It should be measured in neutral with a manual trans and Drive with an automatic.

Doug

 

So while I was putting the T back in so I could reconnect the vac adv hose I likely nudged other hoses off connectors, or they weren't connected in the first place!

The vac delay valve had no hose going out of it, and there were two disconnected hoses. I randomly connected one hose to the vac delay (need to confirm where it goes to). That left one disconnected hose that goes to a Tee in the hose from the connector on top of the throttle body?? Not sure if this hose serves any purpose or not. Based on the diagram above it shouldn't be there? It's the hose identified in the pic below

 

Was the factory timer/delay working before?

it is not uncommon for parts to be bypassed over the years.

Mine is in OEM configuration.

the cruise control, air valve(not sure what its called - on air box) and the vac advance delay are all connected.

Is this part still hooked up?

 

Nick,
can't check the car right now.
However, cruise control deleted by PO, so probably not same as original. Yes, I get it that its common for PO's to monkey around with the vacuum system. Just trying to establish whether disconnected hoses were dislodged by me, or were not connected before I started work in the Vee.
I am going to re-examine the diagram above in relation to my setup to confirm connections are correct. Then fingers crossed!
Not sure if delay was working previously?
The vac adv capsule was original. Maybe not working and that was why it was disconnected...... who knows?!
Are you workingon your beauty over the winter?
Cheers,

Quentin

 

Hi Quentin, I can take a look at mine and map out the routing of the lines, car is in heated garage.

yes, a few things on the agenda for the winter.

Finish the centre console now that I have all the OEM parts i needed, that should be done this weekend.

Replace transmission mount with the one from the Simply Performance TKX kit.

Biggest job is dropping the IRS so I can have the differential ratio changed and helical LSD installed. Not looking forward to that one.

 

Hey, thanks Nick, appreciated!
Your car is going to be beyond awesome when all done.
I just have a couple of fuel hoses still to replace under the hood. Then I will cross everything and fire her up, at which point I will learn whether I screwed up the wiring in the new injectiopn harness
All the best,

Quentin