Timing And Vacuum Advance

[roccorich 16]

Ive been sure the car doesnt feel powerful enough since I bought it a few weeks ago so I finally got round to having a look at the timing.

My bottom flywheel cover is missing so made a TDC mark on the bottom of the flywheel housing and flywheel.

 

With the vacuum advance disconnected and plugged the car is currently set with no advance at idle. Which would explain a lack of power.

With the vacuum still disconnected It advances when revved so the centrifugal whatjamacallit is working.

 

However I got my mate to watch the light while I reconnected the vaccum advance at idle and while revving and It doesnt seem to make a difference. Is this the right way to check it?

Im going to replace the vacuum pipe, where does it run to?

Whats a good amount of advance to start at before I try advancing until it pinks?

 

cheers

 

Rich

 

 

[acox99 74 1 Cars]

Try and suck through the pipe that's connected to the vaccum advance unit, if you can suck through it the vaccum advance unit is knackered and you may as well just blank off the pipe, the vaccum advance only works on initial load when the accelerator is depressed, due to the sudden depression in the manifold, it doesn't make a great deal if difference to the performance.

[roccorich 16]

I'll give that a try when I get a new bit of pipe on it.

Cheers

[roccorich 16]

Just remembered I bought a vacuum brake bleeder that I can check the vacuum advance with.

 

So does anyone know an actual book figure for how many degrees of static advance is normal for a 1.9?

 

Ive seen loads of threads where people just say advance till it pinks but I would like a rough place to start from rather than TDC.

 

cheers

 

Rich

[welshpug 1,661]

if you have a timing light use that, but if not, just wind it till it pinks then back off a bit, it's very easy and will likely be far quicker than faffing with a timing light!

[roccorich 16]

But how much advance is the normal amount?

 

 

Ive found an advance curve that talks about 10 degres so if I set it to 8 and advance from there?

 

Its no extra work as I already have a mark I can use on the bottom of the flywheel.

 

cheers

 

Rich

[DamirGTI 342]

It'll start from anything around 5 to 10 deg. , book figures state 5 deg. @ 700 rpm. / 30 deg. @ 3500 rpm. .

 

But as said , this values will be a bit off now .. due to wear and tear built inside the engine and it's components over the yeas , fuel quality/grade used etc. .. So "by ear" adjustment will be better performance wise .

 

D

[roccorich 16]

Cheers

 

Just wanted somewhere to start.

 

Ive got another dizzy I bought cheap off ebay so I may have a play bending spring posts at some point.

[DamirGTI 342]

5 deg. @ 700 rpm. / 30 deg. @ 3500 rpm. .

 

D

Need to correct myself , sorry , it's - 30 deg. @ 3000 rpm.

 

D

[DamirGTI 342]

Ive got another dizzy I bought cheap off ebay so I may have a play bending spring posts at some point.

 

That might be good idea , cos std. 1.9 dizzy has too much initial advance even for a standard engine . So bending/tensing the initial spring (you can distinguish it by the thickens - the initial spring is made of thinner wire , opposite to the secondary spring which is made out of thicker wire) you'll squeeze a little bit more power/torque from the engine .

 

Few shots of the dizzy internals :

http://forum.205gtidrivers.com/index.php?showtopic=102663

 

D

[roccorich 16]

Cheers.

 

Things could get interesting.

[Jolly Green Monster 51 1 Cars]

Nice info

[roccorich 16]

The vaccum advance is shagged so Ive bunged it up and my idle is behaving better now.

 

H&H say its £25 plus postage to recon my vacuum unit including vat and postage.

 

Gonna see how much my local factors can get a new unit for but that sounds like a good price

[welshpug 1,661]

Rather a lot more than that, IF available, which iirc from a fellow welsh member with a lazer green that they were not.

[iPlod999 143 1 Cars]

GSF quoted me £70 for a new one.

 

So off to H&H my old one went.

[roccorich 16]

£70 just for the vacuume unit?

[iPlod999 143 1 Cars]

Yep.

 

Had none in stock and they quoted direct from the manufacturer. Bosch I think.

[roccorich 16]

Had a little play with the timing.

 

Ive advanced it a couple of times and not got it to pink yet.

 

I found TDC with a screwdriver in the no1 so its obviously not an exact mark.

 

Using my TDC mark I made on the bottom of the flywheel cover my lights saying Im at 13 degrees advance!!!

 

Ive just changed the plugs and they were white before so I know it was running lean, would lean running delay pinking?

 

Im flooring it up a bit of a hill in fifth from about 20.

 

Maybe Ill go try to find a bigger hill...

 

Never actually heard pinking but fron my understanding you would know about it.

Edited October 8, 2013 by roccorich

[Jolly Green Monster 51 1 Cars]

lean would make it pink with less advance..

 

hoping to get a bit of time playing with mine tomorrow.. will report back.

Edited October 8, 2013 by Jolly Green Monster

[roccorich 16]

O and Im running it on shell v power

Cheers

[Jolly Green Monster 51 1 Cars]

same here

[acox99 74 1 Cars]

You can run more advance with higher octane fuels.

[Jolly Green Monster 51 1 Cars]

totally agree, assuming alls well etc..

 

was planning on using detcans to check mine, already done a before power run, will change fuel pump as it was a little leaner than I like, advance the timing a little and check with detcans and a bit more etc.. then put back on the dyno to compare.

 

Simon

mine looks to have been backed right off for 95ron

[Anthony 1,003]

mine looks to have been backed right off for 95ron

You really do need to pull a lot of timing out to run a 1.9 GTi non-CAT on 95RON, and they feel distinctly flat and unresponsive as a result - no doubt why Peugeot never officially sanctioned them to be run on the lower octane fuel, unlike the 1.6 and other models.

 

I'm not sure why owners do it, particularly when I'm far from convinced that there's an economic case either, seeing as you lose fuel economy by retarding the timing that much and probably enough to negate the few pence difference in fuel costs.

[Jolly Green Monster 51 1 Cars]

Agreed.