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Timing??
lowrider - October 18th, 2002 at 06:06 PM

I've just fitted a 1600tp to my Karmann Ghia
that I bought as a rolling shell.
can anyone tell me the timing position; i've seen numerous figures from tdc to 5° atdc to 10°btdc.
Its got the prefix AD in the engine number & came out of a 70-71 kombi.....
thanx guys,
Andy

70AutoStik - October 18th, 2002 at 10:31 PM

Assuming a stock engine:

You will have one to three notches on the pulley. If it only has one, this is the correct timing for static or at idle with the vacuum hose blocked. You can usually advance this by about 2 degrees (about 3mm to the right) without a problem. If you do, try hitting full throttle at various speeds up a steep hill - if you hear a "rattle" (ping,) retard it back to stock and try again.

If it has two marks, the right-hand one is the timing mark. If it has three marks, the second from the right is the correct timing for static - but you'll probably get away with the one on the right.

Over the years I've timed a lot of engines using the hill method - but, I was trained to the sound of ping from an early age - if you find the point of pinging and retard by 4 degrees (2 if you are testing this on a hot day,) you should get pretty close to optimum for your combination.

KruizinKombi - October 18th, 2002 at 11:15 PM

I also use the ping position but found that due to the variations in fuel quality that it was best to stick with the stock timing unless using PULP. :)

lowrider - October 19th, 2002 at 06:48 AM

Thanks guys,
yes, it has 3 notches in the pulley & standard
vacuum dizzy.
I guess ULP is a whole other thing, that
I've read about elsewhere here...
cheers!
Andy:thumb

aussiebug - October 19th, 2002 at 03:06 PM

If you have a 34PICT/3 or similar "two adjusting screw" carby, then all you need to know for tuning is at:
http://www.geocities.com/aussiebug1970/34pict3.html 

If you are using a "single adjusting screw" carby like the 30PICT series, then you need :
http://www.geocities.com/aussiebug1970/30PICT2.html 

For info on fuels for VWs...
http://www.geocities.com/aussiebug1970/octane1.html 

Rob

Tnate - October 19th, 2002 at 06:49 PM

1600 AD model engines are out of a early 70s kombi.

The timing on the engine with a 34 PICT 4 carb is 7.5 degrees before TDC.
Statically, it is the notch on the pully on the right.

Cheers
Tnate

Tnate - October 19th, 2002 at 06:49 PM

1600 AD model engines are out of a early 70s kombi.

The timing on the engine with a 34 PICT 4 carb is 7.5 degrees before TDC.
Statically, it is the notch on the pully on the right.

Cheers
Tnate

aussiebug - October 21st, 2002 at 11:45 PM

Quote:
Originally posted by Tnate
1600 AD model engines are out of a early 70s kombi.

The timing on the engine with a 34 PICT 4 carb is 7.5 degrees before TDC.
Statically, it is the notch on the pully on the right.

Cheers
Tnate


I don't know about the AD series engine being used in Kombis etc - but 990,000 of them were used in beetles from 71 to 73 inclusive. (see the full list of engine numbers at http://www.geocities.com/aussiebug1970/years.html  )

You're right about the timing Tnate, but not completely right. The actual timing for a VW engine depends mostly on the distributor being used, NOT on the carby being used.

If the engine has a single vacuum distributor (either vacuum-only or SVDA -single vacuum double advance), then yes - 7.5BTDC is correct.

But if it has a 009, it has to be timed at 28-32BTDC at 3000rpm, and let the idle fall where it may (usually between 5 and 10BTDC). 009s vary in how much total advance they make, and max advance is more important than idle advance, so the max advance has to be set first with these distributors.

In the USA may of the AD series engines had a DVDA (double vacuum double advance) distributor and these had to be set at 5ATDC (that's AFTER TDC) at idle with both vacuum hoses connected. This was an emissions thing, and it's just possible a few of these distributors found there way to Aus. The retard vacuum hose pulled in the retarded ignition at idle, but the advance vacuum line started working as the rpm rose off idle, so the timing then jumped to 7.5BTDC and then started advancing normally from there.

Tnate - October 22nd, 2002 at 04:56 PM

Aussiebug,

Yeah, I've got a 1600 AD in my 72 super and I knew they were produced for beetles. The problem is that every time I tried to find engines specs, I could only find it in a Kombi manuals. They were used for early 70s bay kombis.

I was reluctant to mention the other timings for the engine as most of them had single advance and I didn't want to confuse Andy.

If it is Australian spec, most likely it will be 7.5 degrees BTDC.

Happy vrooming
Cheers
Tnate