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WTF!!!! Why is setting timing soo hard

Broncobowsher

Total hack
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Jun 4, 2002
Messages
37,063
I just advance it a little at a time until it knocks running full throttle up a hill
Then back off just a little

I have a 90 mustang motor with the mustang efi. And it's currently at 37 degrees

If you go a step further and start backing the timing off until it looses a little power, then go back to the last setting that was good power. That is a better setting. Gives a better safety cushion for a tank of bad gas or odd weather conditions. Less timing at idle helps emissions and idle stability. Makes the engine less sensitive to load.
 

DirtDonk

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Bronco Guru
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Nov 3, 2003
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51,616
Or use an MSD Timing-Advance module for a Duraspark ignition and simply tweak your timing as you go. ;D
Easy beeswax.

Paul
 

Scott C.

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Oct 10, 2009
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Waynetown IN
You can always use a vacuum gage and set the timing to the highest and steadiest vacuum point. I would bet that if you do, it will be further advanced than the factory 6 degrees. But, it will most likely run better. My roadster is actually up around 14 degrees, if I remember correctly. I use a tachometer, vacuum gage, timing light and dwell meter. I adjust the air fuel, idle speed, timing and dwell (if you have points) until it settles in. Plus you need to know how many degrees your vacuum advance adds when you first accelerate, along with at what RPM and at what degree it hits full advance. Working on the distributor you can adjust those too.
 
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jckkys

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A lot of people forget that distributor degrees equal 1/2 crank degrees. 15 distributor degrees is 30 degrees at the crank. Another mistake is simply adding the degrees of vacuum advance to the centrifugal and initial. When an engine is at full throttle there so little vacuum at the port above the throttle plate that the vacuum advance won't start to move. I've checked this myself with a gauge connected with a T to the advance hose. My stock '86 351 with 8.7 to 1 compression runs best with 20-21 degrees of initial timing. When I hear 6-8 degrees I can only think the factory was more concerned about emissions than a good running engine.
The fordmusclemagazine article I cited will walk you through a step by step approach to set up your distributor on your engine for the best results. The parts described are the Ford parts you have. More can be done with a dino and Sun distributor machine but this approach can be done without fancy equipment.
 

KyleQ

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Apr 24, 2008
Messages
5,480
My EFI motor runs sweet - no timing pointer, never checked codes. Advance the timing until it pings, get it warm and try to start it. Back timing off until it stars nice when at operating temp. WIN. Adjust as necessary - some may want more room in the summer heat.

Seriously - over thinking it...
 

jckkys

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The advance curves built into OE distributors, came nowhere near optimal in terms of HP, mileage, or drive ability. A well set up distributor will wake up almost any engine. Whether the carb is tuned or not. A well tuned carb is a big piece too. Getting the whole package working correctly takes work. It's not for those who look for short cuts. They can buy a new Jeep.
 

broncnaz

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May 22, 2003
Messages
24,342
My EFI motor runs sweet - no timing pointer, never checked codes. Advance the timing until it pings, get it warm and try to start it. Back timing off until it stars nice when at operating temp. WIN. Adjust as necessary - some may want more room in the summer heat.

Seriously - over thinking it...

EFI is a totally different animal other than your initial timing the computer pretty much figures the rest to a point.
Now hopefully the OP hasnt gotten confused by all the other info thrown around in this thread. Lots of good info but lets get him running halfway decent before totally confusing him.
 

flexmerc

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Oct 9, 2014
Messages
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X2...Your timing marks could be off. Go ahead and do one of the exercises on the net to determine TDC and when you find it check the timing marks to see if they're lined up on TDC. If they are then pull the distributor vacuum line and plug it and set the timing at 6 degree BTDC. Then plug in the vacuum line and be done with it. This is how the factory recommended doing it on stock 302s. Then if its idling badly you probably have a carb issue.

HIGHJACKING THIS THREAD

When you say 6 degree BTDC, that means the tick marks to the left of the TDC/0 Line? and the numbers to the right of that would be after TDC?
 
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pcf_mark

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Jun 11, 2010
Messages
3,696
The higher the number is up the tab (closer to the water pump) the more advanced or BTDC it is. If you want to get close just set it so the timing mark is at the top of the tab. Should be 12 degrees and run pretty good. If it hot starts fine you are ok to go, if it cranks slow hot then back it up two degrees.

You do not sound like a person who likes to tweak so set it conservative and forget about it.

FYI - setting it to highest vacuum will almost certainly result in too much advance for a stock truck.
 

flexmerc

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The higher the number is up the tab (closer to the water pump) the more advanced or BTDC it is. If you want to get close just set it so the timing mark is at the top of the tab. Should be 12 degrees and run pretty good. If it hot starts fine you are ok to go, if it cranks slow hot then back it up two degrees.

You do not sound like a person who likes to tweak so set it conservative and forget about it.

FYI - setting it to highest vacuum will almost certainly result in too much advance for a stock truck.

I’m a visual learner, to ensure we’re on the same page, please see the attached photo
So when you say 12 that means at idle w/ vacuum disconnected I should see 12 with my timing gun on the right of zero? (All assuming I found TDC correctly)
I appreciate your help
 

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Pa PITT

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.If it's hard to do then . Why not just Take a hammer & tap it left or right & Drive it for a day or 2 .. Don't even try to find out where it's set. Just stop when you've found that proper location. Bump it forward & Then bump it back. I've done this on a few.
One Chebywas on about 23 when I did check it. But that's where it was at home.
 

Slowleak

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.If it's hard to do then . Why not just Take a hammer & tap it left or right & Drive it for a day or 2 .. Don't even try to find out where it's set. Just stop when you've found that proper location. Bump it forward & Then bump it back. I've done this on a few.

One Chebywas on about 23 when I did check it. But that's where it was at home.


That’s what I did with my old C10. I would drive it until it was hot, and then advance the timing to the point where the starter wouldn’t turn the engine over. Then I would back it off gradually until it did. Worked perfect every time.....
 

pcf_mark

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Jun 11, 2010
Messages
3,696
I’m a visual learner, to ensure we’re on the same page, please see the attached photo
So when you say 12 that means at idle w/ vacuum disconnected I should see 12 with my timing gun on the right of zero? (All assuming I found TDC correctly)
I appreciate your help

I have not used a timing tape in 20 years since I bought a dial-back-to-zero timing light. You want the part you have the arrow pointing to (short end) up by the water pump and the rest of the tape wrapped down and around toward the driver's side. Then the 10 (or 12 or 16) you want to read is OPPOSITE not the one you have highlighted. You want to be advancing into the long end of the tape. If you go to the short end (marked 0 to 10) you are retarding your timing and it will run worse.

Check this out http://www.jegs.com/InstallationInstructions/100/121/121-8985.pdf
 

flexmerc

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Oct 9, 2014
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Thanks mark and PITT, you’re method is more my level, appreciate it!
 

roundhouse

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Sep 5, 2003
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That’s what I did with my old C10. I would drive it until it was hot, and then advance the timing to the point where the starter wouldn’t turn the engine over. Then I would back it off gradually until it did. Worked perfect every time.....



That’s what i do
Find a hill and run up it full throttle
Advance the timing a bit and do it again

When it starts pinging , retard the timing a little

I dont pay any attention to the numbers
 

bknbronco

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Jan 17, 2011
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North Metro, MN
maybe we need to start with new points and condensor and set them up correctly then move on to timing.

I also use a dial back timing light. set the light to what you want your timing to be and turn the dist till the pully TD mark lines up with the pointer. super easy to adjust if you use a adjustable light
 

73azbronco

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Basic tune up, replace the simple parts, coil, plugs, wires, condenser/points if it has those. Set basic BTDC. Using a vacuum gage adjust motor to idle it's best with the vacuum gage as a reference. Then go back and check timing and start to play with that and doing test drives. Whatever works best is where it needs to be, damn the numbers on the crank.
 
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