Factory Five Racing Forum banner
1 - 13 of 13 Posts

·
Junior Charter Member
Joined
·
411 Posts
Discussion Starter · #1 ·
I'm trying to time my ignition here.
do I follow the pointer at the top mark of the pointer.
I notice their is another space pointer in the middle.
I'm using a stock 302 pointer.


eric
 

·
Junior Charter Member
Joined
·
411 Posts
Discussion Starter · #3 ·
Thank you.
I'll try to set the timing.
I notice when I set to 10 degree at idle. the car run very rough. should I increase the idle screw?

thanks

eric
 

·
Banned
Joined
·
7,701 Posts
Make sure you remove the SPOUT (Spark Out) plug before you set base timing. It's the little square plastic plug in the harness that feeds the distributor; it hangs about 3 or 4 inches away from the distributor plug.
 

·
Blue Oval Scribe
Joined
·
9,177 Posts
GBranham, according to his sig he's running a carb....

Eric, what distributor are you using and does it have vacuum advance on it?

Mark
 

·
FFCobra Fanatic
Joined
·
12,975 Posts
Eric 10* may not be the final best initial timing setting but should be close enough to let you adjust the carb out some, but may want to start at 12*. Like Mark asked,what dist. is being used and does it have a vacum advance also. Vacum advance must be disconnected and pluged when setting timeing. With the set up in your sig you may find initial timing ends up in the 12-16* range but only testing will decide. The total amount of timing is more importand then the initial timing. It should be about 32-35* total at 34-3600rpm's.
Set at 12* then try to get carb (mixture and idle screws) adjusted for a test drive.
 

·
FFCobra Craftsman
Joined
·
2,315 Posts
A related question here-- if I'm using a duraspark distributor and need to change the centrifugal advance "arms" inside to limit mechanical advance -- where do I get them?

My duraspark came with a 13L/18L arm inside. If I'm going to stick to 34/35/36 degrees of total advance with 12 degrees initial, then I will be needing an 11L or 12L arm.

As for total timing, I have read elsewhere that my 302 will make maximum power with something more along the lines of 38 or 40 degrees total timing -- but the standard wisdom here is "don't go past 36 degrees or you'll have a bucket of parts on your hands".


Can any of the engine builders here comment? I will be running my car on a steady diet of premium (91/92 octane) fuel.

-SB
 

·
FFCobra Fanatic
Joined
·
2,600 Posts
Set with Vac advance disconnected and idle speed lower than the mechanical advance starts to kick in. Start at 10deg advance. Rev engine to 3000rpm and check timing, should be no more than about 35 degrees. Adjust base timing to set. For more info: Bob's page
Ford muscle
Carb ford page
last one

Mine came with a 21L and an 18L. I welded the slot smaller. A bushing on the pin in the slot would work if you know if they are available.

"To figure approximate slot width for a given advance figure Multiply the number of desired centrifugal degrees by .013" then add .150" to account for the width of the stop pin."

8L slot = 16 degrees centrifugal advance = .358”
9L slot = 18 degrees centrifugal advance = .384”
10L slot = 20 degrees centrifugal advance = .410”
11L slot = 22 degrees centrifugal advance = .436”
12L slot = 24 degrees centrifugal advance = .462”
13L slot = 26 degrees centrifugal advance = .488”
14L slot = 28 degrees centrifugal advance = .514”
 

·
Junior Charter Member
Joined
·
411 Posts
Discussion Starter · #10 ·
Hey guys I'm using MSD 8579 pro-billet distributor. It a mechnical advance.
I forgot to mention. I'm using a very lumpy cam. that might be also the cause of keeping it at 800rpm idle. on top of that My AED 750 carb does not have a choke valve.... trying to keep this thing idle when is cold, is a little tough....

THanks again.
eric
 

·
FFCobra Fanatic
Joined
·
12,975 Posts
You may find a bit more then 10* is needed for initial once you set total. It is more important to set the total timing,then let the initial fall where it may as long as you don't run into a hard hot start or detonation under load. 800 rpm's is not a real high idle. You may find it needs to be 1000rpm or more with a radical cam.
 

·
FFCobra Craftsman
Joined
·
2,315 Posts
Originally posted by Sanford:

Mine came with a 21L and an 18L. I welded the slot smaller. A bushing on the pin in the slot would work if you know if they are available.

"To figure approximate slot width for a given advance figure Multiply the number of desired centrifugal degrees by .013" then add .150" to account for the width of the stop pin."

8L slot = 16 degrees centrifugal advance = .358”
9L slot = 18 degrees centrifugal advance = .384”
10L slot = 20 degrees centrifugal advance = .410”
11L slot = 22 degrees centrifugal advance = .436”
12L slot = 24 degrees centrifugal advance = .462”
13L slot = 26 degrees centrifugal advance = .488”
14L slot = 28 degrees centrifugal advance = .514”
Does anyone know where to get an 11L or 12L rotor?

- SB
 

·
FFCobra Fanatic
Joined
·
2,600 Posts
I believe its luck of the draw when you buy an '85 dist from the auto store.
PS don't try to bend the tabs in to make the slot smaller, they'll break.

[ December 14, 2006, 01:25 PM: Message edited by: Sanford ]
 
1 - 13 of 13 Posts
Top