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Hotcorner 04-14-2021 08:54 PM

Pertronix Advance
 
Can someone help me with a question for a Pertronix distributor? With a 350 with an RV cam, where should I start as far as springs and advance limiters? Should I lock out mechanical advance and rely on vacuum advance?

geezer#99 04-14-2021 09:53 PM

Re: Pertronix Advance
 
It depends on your set up.
A stock versus modified thing.
Stock motor might like a lazy timing curve and a modded motor might like something more aggressive.
What motor, cam, heads, intake, carb, trans, rear gear ratio all play a part.
How is yours set up?

Hotcorner 04-14-2021 10:16 PM

Re: Pertronix Advance
 
Quote:

Originally Posted by geezer#99 (Post 8908569)
It depends on your set up.
A stock versus modified thing.
Stock motor might like a lazy timing curve and a modded motor might like something more aggressive.
What motor, cam, heads, intake, carb, trans, rear gear ratio all play a part.
How is yours set up?

Stock motor with Edelbrock intake and carb. Believe it’s an RV cam. SM465 trans. 3:73 gears an 33” tires. Loves to pull from low RPMS

geezer#99 04-14-2021 10:19 PM

Re: Pertronix Advance
 
What’s your initial timing set at?
That’s the best place to start.

Hotcorner 04-14-2021 10:44 PM

Re: Pertronix Advance
 
Quote:

Originally Posted by geezer#99 (Post 8908582)
What’s your initial timing set at?
That’s the best place to start.

It likes 13 deg btdc

geezer#99 04-14-2021 10:50 PM

Re: Pertronix Advance
 
Is your pertronix completely adjustable?

Usually you want total timing (mechanical+initial) to be near 32 degrees all in by 3200 rpm.
With your 13 you’ll want about 20 mechanical.

Hotcorner 04-14-2021 10:54 PM

Re: Pertronix Advance
 
Quote:

Originally Posted by geezer#99 (Post 8908590)
Is your pertronix completely adjustable?

Usually you want total timing (mechanical+initial) to be near 32 degrees all in by 3200 rpm.
With your 13 you’ll want about 20 mechanical.

Yes. Different springs and limiters came with it.

Wrenchbender Ret 04-14-2021 10:58 PM

Re: Pertronix Advance
 
Do not block off the mechanical advance.
George

Hotcorner 04-14-2021 11:09 PM

Re: Pertronix Advance
 
Quote:

Originally Posted by Wrenchbender Ret (Post 8908595)
Do not block off the mechanical advance.
George

Roger.

geezer#99 04-14-2021 11:09 PM

Re: Pertronix Advance
 
Did you get charts with it to tell you what springs etc to use for desired settings.

You’ll likely want it to be fairly lazy to begin with.
You’ll need to experiment to see what your motor likes.

I’ve got a motors manual here with distributor specs.
Would you have the original distributor with part number.

Rich72C10 04-15-2021 03:56 PM

Re: Pertronix Advance
 
may want to take a look at my thread (page 3), I put my all in at 25K with the springs that are included.

https://67-72chevytrucks.com/vboard/...=818178&page=3

My Truck, from post1
SBC 350 Rebuilt less than 1k on engine at this posting.
TH350 Rebuilt at same time as engine.
307 Gears
Power Brakes and A/C (off during all timing checks)
12° Initial timing
30° ~3500 Max Mechanical (by offsetting light ° button to read 0 on the timing mark)
45° ~3500 Max Vacuum (by offsetting light to read 0 on the timing mark)
17 hg Vacuum @idle
Park/Neutral Idle 650
Tires 275 60 15
60 MPH = ~2500 RPMs


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