Ignition Advance

[mattcogg]

Hi,

The ignition advance has been unused on my car for ages! But lately after many conversations it seems I maybe missing out. A mechanic told me that I didn't need the ignition advance and threw loads of technical info at me about not retarding an already advanced ignition blah blah blah! And he seemed to know what he was talking about it so I listened. However I know you guys r really in the know and wondered if anyone could give me a good reason why the ignition advance would not be used! I have a 1400 sr engine on a carb pretty standard setup. Any info would be a great help plus what I can do if the ignition advance is broke.

Thanks again :D :D :D

[mikeoxford]

do you mean the vacuum advance unit on the dizzy?

[Nova-Boy]

the vacuum ignition advance is a device used to advance the ignition instantly when you put your foot down in addition to the weights in your dizzy.

Most of the time the diaphragm has gone and it does not work. If this is the case when setting up the timing they advance to ignition to compensate. The car will run ok but wont run as well over the whole rev range as if it did work.

The reason the machanic will have said about not needing it will be because like i said it will be advanced to compensate this.


not retarding an already advanced ignition

Pluss they cost about ?70 to buy new and you nee a 5.5mm small socket to strip the dizzy and fit it.

[mattcogg]

Yeh i mean the vacuum advance on the dizzy (sorry)! So in your opinion would it be best to get it fixed or is it ok as it is! I really want to squeeze every bhp out! Does it effect acceleration and other things? I also have a set of magnecors from an astra that I want to fit but the cap won't fit so I will have to replace the whole dizzy! If I want one is a scrapper or brand new can you test the diaphragm by sucking on the end or is that a wind up?

Thanks
Matt :D :D :D

[Nova-Boy]

Yeah I would get it fixed. It does affect the aceleration and sometimes will feel like its not pulling at all?? It is mostly affected when your say doing 30 in 4th and then put your foot down. It will cause your car to pink and not pull.

Get a full dizzy from a scrapper as they dont usually like to sell them seperate. You can check the unit by sucking on the pipe. If there is resistance it works. If you can suck straight through it dont work. If you can get a full working dizzy just swap it over. Much easier than changing the advance unit.

As for the astra stuff i have no idea sorry.

[mattcogg]

Thanks,

I will get a new dizzy from a scrapper! I am just really worried about getting the wrong one! I have a 1.4sr but the whole thing is a hybrid are they all the same. I have a 1.6cam in, when I went to change the leads and cap the cap was 1.2 and rotor arm 1.4! I suppose it would be best to take the dizzy with me to the scrapper. Or is the end part ie cap, rotor arm pretty interchangeable! Sorry I am just really confused!!!

Thanks
Matt :D :D :D

[Nova-Boy]

I think most of the dizzys are the same. I got one for my 1.2 of a 1.3sr. Not sure if the 1.4 is the same? If they are different or not sure just strip it down and swao the advance unit. Not too bad just a bit fiddly. Gives you a chance to clean all the contacts and free weights etc. while your at it.

Why have you got a GTE cam in your 1.4sr? The 1.4sr had higher lift and duration over the 1.6?

[rgv_stu]

prove it

lift may be bigger but is the duration longer???

[Nova-Boy]

Just from reading the 1.2 tuning guide it says to put a GTE cam in , but then after a large discusion it was decided that a 1.4 cam would be better.

I just tagged duraion and lift in as the same, sorry :oops:

But would he be better off with a 1.4 cam or GTE cam in his SR?

[Aragorn]

14SR has higher lift on exhaust valve - no data on duration tho

and u prolly find the SRi and late GSis are different again since haynes has no data on them at all

14SR uses microprocessor controlled ignition 12 and 13 are electronic breakerless shite

14 has the lil ignition module and a different sensor in the dizzy

the rotor for 14SR is the same as all the 1400's and the 1600'd not the same as 1300 or 1200?? same with the dizzy cap cept its unique to the 1400sr according to the EPC

get a full dizzy from a 1400SR (or even a 1400 astra mk2/cav mk3) and use that - with its original dizzy cap and rotor

u may find its worked cos the 1200 rotor will work with the 1300 cap :/

still dodgy tho - get the full SR setup back on there

[Ste_Nova]

my vac unit for my 1.4sr engine was ?14

[Nova-Boy]

?14 :o Where from? Brand new?