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Old 03-21-2017, 09:43 PM   #1
StanleyRosiello
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Timing adjustment

Hey guys. Got a 302 crate engine the the PO put in. At what rpm do I need to set the timing and at what degree? Thanks in advance.
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Old 03-21-2017, 09:54 PM   #2
GASoline71
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Re: Timing adjustment

302? is it a DZ code 302?

Will need more info on engine to recommend what timing to set it at.

Gary
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Old 03-21-2017, 10:04 PM   #3
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Re: Timing adjustment

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Originally Posted by GASoline71 View Post
302? is it a DZ code 302?

Will need more info on engine to recommend what timing to set it at.

Gary
Sorry... 305. I'm new to this stuff. What is a dz code?
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Old 03-21-2017, 10:11 PM   #4
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Re: Timing adjustment

A stock 305 Id start at like 8 initial advance with vacuum advance disconnected and engine warm,use a timing light
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Old 03-21-2017, 10:43 PM   #5
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Re: Timing adjustment

He's in Ogden, Utah. At that elevation I would start at 10 - 12 degrees initial timing.
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Old 03-21-2017, 10:43 PM   #6
geezer#99
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Re: Timing adjustment

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Originally Posted by StanleyRosiello View Post
Sorry... 305. I'm new to this stuff. What is a dz code?
DZ is the suffix code for a Z28 302.
For your timing look here to figure it out.
http://www.badasscars.com/index.cfm/...d=76/prd76.htm
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Old 03-21-2017, 10:45 PM   #7
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Re: Timing adjustment

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He's in Ogden, Utah. At that elevation I would start at 10 - 12 degrees initial timing.
You're sitting higher than he is.
What's your initial like?
I usually run 14 initial at sea level.
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Old 03-21-2017, 11:02 PM   #8
truckster
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Re: Timing adjustment

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You're sitting higher than he is.
What's your initial like?
I usually run 14 initial at sea level.
I'm only about 500 feet higher.

I'm just making the point that the higher elevation means he can safely advance the initial timing more than the factory specs.
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Old 03-22-2017, 06:59 AM   #9
StanleyRosiello
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Re: Timing adjustment

Thanks guys. I'll probably set it tonight. So do I set it at 10-12 at idle or do I need it to be at a certain rpm?
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Old 03-22-2017, 09:37 AM   #10
geezer#99
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Re: Timing adjustment

10 to 12 is only a starting point. At elevation you'll likely be up closer to 16.
Set it with the vacuum plugged to the vac pot and at the lowest rpm it will idle at. Preferably below 700 rpm.
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Old 03-22-2017, 11:48 AM   #11
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Re: Timing adjustment

Let me tell you a story about a Ford guy with a motorhome. Similar situation. Dialed in 16 degrees timing as he was told, and it did indeed run the best there. Many of our motors will... I think I have 12-14 degrees into my 402.

Sadly he also had 28 degrees of mechanical timing built into the centrifugal advance of the distributor, so each time he went through the mountain pass on the I-90 he grenaded the motor. Broke ring lands off pistons, the whole deal. And he did this twice believe before he brought the motor in to be dyno'd.

The answer there was to put it on the distributor machine and take some mechanical advance out of it.

The lesson is that your distributor has a certain amount of mechanical advance built in. If that was designed to work with some small amount of initial timing like 4 degrees and you add another 12, you may have WAY too much at higher RPM. So if it turns out to need that much to run well, do be sure to have the high RPM timing checked with a light at least to make sure it's not wildly advanced.
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Old 03-22-2017, 12:29 PM   #12
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Re: Timing adjustment

So true dave, but we'd hope with the links stanley got he'd read them and adjust accordingly.
Another for adjusting your mechanical.
http://www.crankshaftcoalition.com/w...EI_distributor

So, was the ford guy stone deaf?
Shoulda heard the loud rattle!
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Old 03-22-2017, 01:53 PM   #13
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Re: Timing adjustment

I know, we couldn't figure out why he never heard detonation. I -assume- it was a front-engine motorhome, not a rear "pusher" type.
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