Before you start barraging me with "ums" and "ahs", I am well aware that a 009 dizzy should be timed to 32BTDC @ 3000RPM.
My question though is this.
A friend of mine has one on his '69 1500 beetle. I went to tune it for him yesterday (tappets, carb, dwell etc) and noticed that his 009 dizzy is
timed stock.
It is timed at 7.5BTDC statically. Now can someone tell me if this is hugely retarded/advanced, or if it is somewhere in the ball park of correct
ignition.
I have no timing light (never had a need) but do want his car timed properly.
The car does run very well and seens to have no pinging.
Cheers
Tom
The assumption would have to be that if the engine is not pinging and running well that the timing is pretty good.
On my engine we set the timing at idle rather that setting it at 3k rpm i have it set at about 6degree's at idle and it hits 30 degrees around
3.5k
if you assume that my 009 is close to normal then 7.5 degree's should be pretty close on a normal engine
From memory, a 009 produces 20-22 degrees of advance. The recommended range for a stock engine is 28-30 degrees total advance, putting your
mate's engine right in the middle. An extra 2.5 degrees won't make a huge difference to performance; but the usual procedure is to
gradually increase the advance and drive full-throttle up a steep hill, with the engine at 2800+ rpm (to get full advance from the 009.) Find the
point where it begins to ping and back off at least 2 degrees from that (some say 4, and if it's humid or warm, use that figure.)
And invest in a Xenon timing light - it's worth the money.
Here's how it works.
The 009 produces no advance at idle.
It starts to advance at 1200-1300rpm and it's fully advanced at about 2500-2600rpm.
That why they are set with the rpm at 3000+ - to make sure the total advance is "all in".
009s are supposed to produce about 22 degrees of total advance, but they vary - cheap build - from about 20 to 25 degrees total advance.
And since the max advance is MUCH more important than the idle advance, the 009 must be set at 28-32 degrees at 3000+ rpm and let the idle fall where
it may - usually somewhere in the range of 5-10BTDC.
Use as much of the 28-32 as the engine can take without pinging/detonating when you floor it in fourth gear at 50mph (80kmh). Why that speed? - it
happens to be the lowest speed at which the full advance is just about all-in - dependiing on the beetle model (gearing) - 50mph is between 2550
(1600dps after 73) and 2800 (1200/1300s).
Using as much of the 28-32 as you can means it will be a little closer to the max advance of the vacuum distributors (40-42 degrees) for better
economy, and it can reduce the dreaded "009 flat spot" if your engine sufferes from it (a common problem with the 009 and the 34PICT/3 carby
especially - less of a problem with the smaller 30 and 28 series carbs).
Never use less than 28 degrees or the engine will be underadvanced at higher rpm and run hotter than it needs to. If it still pings (as per the test
above) at 28 degrees, use a higher octane fuel and try to get the advance up a little more.
Once you have the car running well with the 009, you can THEN measure the idle or static advance, and use THAT figure for tuning THAT 009 on THAT
engine in future if you wish to do it that way.
Tnate - your friend is probably just fortunate that the 7.5BTDC on his own 009 falls in the 28-32 range at 3000+ rpm, some will, some wont.
When first installing a 009 that's what you do first anyway - set it at about 7.5 BTDC just to get the engine running, then do the 3000+rpm
thing.
For info, 28 degrees is 43.5mm to the right of TDC around the pulley rim and 32 degrees is 49.5mm to the right of TDC.