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Old 03-04-2015, 04:10 PM   #1
1972BlueC20
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what timing are you running?

Looking to hear what timing you'rE running along with what type of engine.

Initial timing?
Total timing?

Vac advance or no?

hooked to ported or manifold vacuum?


I'll start :

350 / 330 Hp with Vortec Heads PART # 19210008

12 initial
around 32 total

vac advance hooked to ported vacuum.

truck isn't running great lately, either having carb or timing issues....going to be playing with it soon....looking to hear the spectrum of different timings on these trucks.....I know it varies and that all engines like different timings.


Thanks in advance!
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Last edited by 1972BlueC20; 03-04-2015 at 04:19 PM.
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Old 03-04-2015, 08:28 PM   #2
JimKshortstep4x4
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Re: what timing are you running?

Engine, 427 BBC, initial timing 14 degrees btdc, 34 degrees total all in by 2800 rpm, vacuum advance, 12 degrees, hooked to manifold vacuum

335 hp, 470 ft/lbs torque (factory rating)

Jim
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Old 03-04-2015, 08:47 PM   #3
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Re: what timing are you running?

Engine 462 CI, 18 initial, 40 all in at 3000 RPMs. No vaccum advance.

459HP/495TQ.
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Old 03-04-2015, 08:56 PM   #4
Fitz
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Re: what timing are you running?

Quote:
Originally Posted by 1972BlueC20 View Post
Looking to hear what timing you'rE running along with what type of engine.

Initial timing?
Total timing?

Vac advance or no?

hooked to ported or manifold vacuum?


I'll start :

350 / 330 Hp with Vortec Heads PART # 19210008

12 initial
around 32 total

vac advance hooked to ported vacuum.

truck isn't running great lately, either having carb or timing issues....going to be playing with it soon....looking to hear the spectrum of different timings on these trucks.....I know it varies and that all engines like different timings.


Thanks in advance!
16 initial, 38 total at 3000 no vacuum advance.
572 big block, 630 HP, 650 Ft-Lbs torque
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Old 03-04-2015, 08:59 PM   #5
1972BlueC20
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Re: what timing are you running?

Quote:
Originally Posted by JimKshortstep4x4 View Post
Engine, 427 BBC, initial timing 14 degrees btdc, 34 degrees total all in by 2800 rpm, vacuum advance, 12 degrees, hooked to manifold vacuum

335 hp, 470 ft/lbs torque (factory rating)

Jim

Hey Jim!

So if your running 14 initial with the vac advance hooked to manifold (constant @ idle) which produces 12 degrees, is your reading at idle 26 degrees?
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Old 03-05-2015, 12:52 AM   #6
SierraMtns
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Re: what timing are you running?

Quote:
Originally Posted by 1972BlueC20 View Post
Looking to hear what timing you'rE running along with what type of engine.

Initial timing?
Total timing?

Vac advance or no?

hooked to ported or manifold vacuum?


I'll start :

350 / 330 Hp with Vortec Heads PART # 19210008

12 initial
around 32 total

vac advance hooked to ported vacuum.

truck isn't running great lately, either having carb or timing issues....going to be playing with it soon....looking to hear the spectrum of different timings on these trucks.....I know it varies and that all engines like different timings.


Thanks in advance!

Whats the details on your carb? I would get that figured out first before working on timing.

What dist are you running? HEI?
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Old 03-05-2015, 10:10 AM   #7
1972BlueC20
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Re: what timing are you running?

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Originally Posted by SierraMtns View Post
Whats the details on your carb? I would get that figured out first before working on timing.

What dist are you running? HEI?

It's a Holley 670 street avenger with electric choke and vacuum secondaries.

I was told by several people on the board to always rule out timing issues before changing parts in a carb.

I've done all the adjustments on the carb. The only things left to do to the carb would be to tear into it and change squirters, powervalves ect....I'm having similar issues with this carb and another edelbrock carb so I'm beginning to think it's something other than the carb.
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Old 03-05-2015, 10:20 AM   #8
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Re: what timing are you running?

Quote:
Originally Posted by 1972BlueC20 View Post

I was told by several people on the board to always rule out timing issues before changing parts in a carb.
Ditto on that. Get the ignition right first then adjust the carb.
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Old 03-05-2015, 01:48 PM   #9
71K20chevy
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Re: what timing are you running?

Engine, pretty much stock 350. 14* initial, vac advance on manifold vac, and recurved mechanical advance.
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Old 03-05-2015, 01:55 PM   #10
1972BlueC20
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Re: what timing are you running?

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Originally Posted by 71K20chevy View Post
Engine, pretty much stock 350. 14* initial, vac advance on manifold vac, and recurved mechanical advance.

cool, thanks for the reply.

So correct me if I'm wrong but since you're running to the manifold port for your vac advance wouldn't you have 14+whatever you vac advance produces at initial idle?


Thanks,
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Old 03-05-2015, 02:18 PM   #11
71K20chevy
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Re: what timing are you running?

Quote:
Originally Posted by 1972BlueC20 View Post
cool, thanks for the reply.

So correct me if I'm wrong but since you're running to the manifold port for your vac advance wouldn't you have 14+whatever you vac advance produces at initial idle?


Thanks,
That is correct. I've never measured it, but I would guess that the vac advance adds about 15*, giving around 30* idle timing. Oh the things you can get away with on a low compression motor!
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Old 03-05-2015, 04:17 PM   #12
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Re: what timing are you running?

14* at idle not sure what it is after that.

350 zz3 heads and lopey cam and 600 holey vac sec with electric choke.

I dont think it likes that because I have a slight stall from idle to wot.

Will try and work that out when its back in the truck.
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