924Board.org

Joes924Racer · Posted: Mon Sep 27, 2004 2:09 am Post subject: Correct way to set my timing.

it runs 'Ok' though Im thinking its to retarded so
Ill set the timing mark dead on with the gun then the book say '-3'
at 950rpm is that retarded 3 ' seems it should be advanced 3'.
Im stuck here.
Is there any way to check advance timing at a given rpm with gun
a have a dial for preset timing advance settings guess I just hook it up and unhook the vacuum dizzy tube and rev it up to 4500 rpm set with 41 'advance.

Someone help me here I want to get this done today. K
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

FrankNL · Joined: 13 Sep 2004 Posts: 9 Location: The Netherlands

You would like to have a spark BEFORE BDP! So -3 will be 3 degrees before BDP, so before the 0 mark on the flywheel.
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Porsche 944 turbo '87 - maranchino red
Porsche 924 '84 - guards red

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

Joe,
Look at your manual. With the -3 and the vacuum hoses attached your running actually 3-4 btdc because of the vacuum retard of 7-8 degrees.

Distributor = 30 degrees
Distributors mechanical advance = 6
Static timing = -3
So, to run 41 degrees full advance set it at 2 atdc with vacuum hoses attached. No more than that or you will ping at high rpms

distrib plus mech advance = 36
-3 is static
Vacuum retard 6-8
-3 your actually running at 4 btc with vacuum retard disconnected
4 plus 1 = 5
36 plus 5 = 41
5 is optimal with vacuum hoses disconnected but check your full advance to be sure. 6 btdc and you will ping at 42 degrees.

If all else fails, set it at -3 atdc vacuum hoses connected to be safe. Then you will have no danger of pinging. Your full advance will only be 40.
Anyone who sets 0 or higher " with" vacuum hoses attached will eventually damage the engine.

My vacuum was weak so I had to recalculate from the book. I’m only retarding 6 degrees on my distrib.. That’s why you should do a full advance test to be safe and sure because every car is in slightly different running shape.
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

Jazzerpet · Joined: 07 Apr 2003 Posts: 186 Location: Omaha, NE.

Augidog, very well put. I will save this info for future reference. I am still amazed at the vast knowledge of our board members.
_________________
1980 931
1985 ½ 944
Member of the “Omaha Crew”

Joes924Racer · Posted: Tue Sep 28, 2004 11:22 am Post subject:

K I put some paint in the flywheel mark that helped..set it 3
and drove it to work and amn it was nice. I have to thank you
guys for all the imput all i did was study the manual and though Id ask here.

Thanks.

_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Lizard · Posted: Tue Sep 28, 2004 3:31 pm Post subject:

well about 6 deg BTDC is the sweet spot according to Vaughan, which is roughly where I run mine, I really find it hard to look in that small window at the back and I always just tune it by ear and how it responds when I blip the throttle.
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3 928s,

Joes924Racer · Posted: Fri Oct 08, 2004 12:08 pm Post subject:

Well I set it at 2 degrees. Hey I took a nice pic of the little window last weekend also. Ill upload after I get back goin out for a little ...anywho
Ill show you guys where Im aiming at in the window K when I upload the pic.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Joes924Racer · Posted: Fri Oct 08, 2004 2:47 pm Post subject:

Ok heres what I did hooked up the leads to the battery tyhen clamped the
timing light wire to the #1 cyl. lead set my adjustable timing light at 2-3
then lined up the zero with the mark that the blue pointer I added in the pic
points to on the bellhousing. thats with the vac lines still connected..runs not bad doesnt ping

So do I need to set my adjustable advance timing light at 6 then put the
zero mark on the flywheel to the point on the bell housing.

_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Joes924Racer · Posted: Sat Oct 09, 2004 12:34 pm Post subject:

come on does the arrow point to the right spot.
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

Roger · Joined: 06 Jan 2003 Posts: 1235 Location: Cordova, TN

I have the same mark, I have allways used it as TDC
_________________
1981 924 NA

Some people are like Slinkies. Not really good for anything, but you
still can't help but smile when you see one tumble down the stairs.

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

Joe,
If that is the 0 tdc mark than whatever you set your advance timing light to, that mark will be centered in that window.
For example your timing light is set to 0
if you center that mark you will be at 0
If your timing light is set to 5 btc, than you line up the same mark in the window you will be at 5 btc.

remember 5 btc vacuum lines disconected- or-
-2 atdc with vacuum lines attached.
Timing is everything.Its my passion with this car to get it just right.
Goodluck.
_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.

Joes924Racer · Posted: Sat Oct 16, 2004 11:42 am Post subject: Augidog

Augidog When you said this it kind of looped me 'well' I
followed the first part where you wrote remember 5 btc vacuum lines disconected I can do that with my timing light how do I do it with
my light to -2 atdc with vacuum lines attached. It would be best to go
to (0) with my light then retard it a bit............ What I did was set it to 5 with out removing the dizzy lines. So instead of going to Zero then retarding a bit maybe Ill just start it up and remove the dizzy lines
set the gun to 5 and set it and try it... I need the sweet spot.

remember 5 btc vacuum lines disconected- or-
-2 atdc with vacuum lines attached.
Timing is everything.Its my passion with this car to get it just right.
Goodluck.
____________
_________________
1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

augidog · Joined: 03 Mar 2003 Posts: 1360 Location: New Jersey

Joe,
If you can set to -2 with your advance timing light, than the 0 mark is actually -2 because the timing light is compensating to that degree.

Whatever you set the timing light to- the 0 mark in the window is that timing.

For instance:
5 btc set on your timing light -is now the 0 mark in your window
-2 on your timing light- is now the 0 mark in your window.

With vacuum lines disconnected to the distributor, put it at 41 degrees and rev at 4500 the 0 mark should be in your window and you just checked your full advance.

_________________
1978 924 95 mile daily driver.
Audi TB/POR174M/High Flow Cat/2.25" exhaust
I knew that positive thinking thing wouldn't work.