vacuum advance unit

[jammygit]

i need to replace this and have discussed with TVR dealer spares. They advised that this unit cannot be obtained separately and are now only available with whole distributor at cost of around £400.

i have contacted RPI for info - awaiting answer. but would they know which type i require?

can anyone help, pass on useful advice etc?
car is a 95 4L HC

[zippy500]

I thought it was only a standard Range Rover one. Try some ignition speialists in your yellow pages. They may be able to get one. But first try the TVR specialists like Joolz, Tower View and Penninsula etc. Sorry if I missed others out. Im pretty sure it is held on by 2 bolts so must be available somewhere as a seperate unit.

[shpub]

It's a standard Range Rover one....

First there are at least 4 if not 5 different standard dizzies fitted to the Range Rover not including the distributorless system fitted to the later RRs.

There are some TVRs that have had the advance modified to cure pinking/running problems so don't throw the old unit away as you may need to retrofit the advance weights. Small chance but no chance if you don't have the original.

The other approach is a scrapped TVR of the same age ish.

Steve
www.tvrbooks.co.uk

>> Edited by shpub on Friday 2nd August 13:46

[SMALLEY]

A scrapped TVR! Excuse me whilst I have a cry

[2 Sheds]

If RPI cant help try V8 Developments, 01775 750000 should be about £200

[IPAddis]

When I had my camshaft replaced by V8 Developments, they capped off the vac advance as they said the new cam was better without it. If you are likely to need a new cam soon, might it be better to put the 200 quid towards that?

Ian A.

[2 Sheds]

quote:
When I had my camshaft replaced by V8 Developments, they capped off the vac advance as they said the new cam was better without it. If you are likely to need a new cam soon, might it be better to put the 200 quid towards that?

Ian A.

Yes if its just the vacuum advance thats shagged, you can just cap off, infact if you have experienced any pinking problems this may improve things, but make sure that the distributor is functioning correctly.

[david beer]

I must admit my 99 Griff 500 timing is set up without the vac advance.

[jammygit]

thanks for all the posts on this - to keep you updated neil@penninsula is attempting to source the correct part that will fit.
interesting to hear that some have blocked their units. would you not get better performance if the advance was working as it should do? if not why not?

physics lesson please

[shpub]

Capping the distributor is a bit like playing Russian roulette: works on some but not all and if the timing is out then high revs pinking/predetonation is a possible result - kiss goodbye to the engine. The advance may be set statically by disconnecting the vacuum but that is effectively setting the ignition statically which is not a good idea if you want the best. The vacuum basically changes the ignition timing to compenstae for higher revs and allows the timing to be just that bit different to give you extra horsepower. As the engine vacuum builds up, the ignition is changed. Advanced OTTOMH...

If the dissy/engine was designed/setup for advance then it ought to be used. Disconnecting it will change the ignition advance which may be good or very bad for the engine depending on circumstances.

Steve

[2 Sheds]

The majority of TVRs especially earlier cars, will benefit from no vacuum advance, Engine builders tend to disconnect,If set up properly there will be no damage to engine. Bottom line, Take it to a specialist.
Tim

>> Edited by 2 Sheds on Tuesday 6th August 11:08

>> Edited by 2 Sheds on Tuesday 6th August 12:44