timing for dd 350

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Andrew511
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timing for dd 350

Post by Andrew511 » Mon Oct 07, 2019 12:51 pm

I tried searching the old posts and couldn't find a reliable answer. I have a chevy 350 running DD with HEI distributor and a brand new holley 390cfm 2 barrel. I don't know very much about timing but I need something to relay to my mechanic so he can have somewhere to start with timing this thing. he was told that he shouldn't set this up like a normal truck engine because the timing is different for a dd airboat

unforgiven11B
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Re: timing for dd 350

Post by unforgiven11B » Mon Oct 07, 2019 7:24 pm

32* total, vacuum advance disconnect and plug. Get a Mr.Gasket spring kit and toss the lightest springs in it so the mechanical comes in ASAP.

Andrew511
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Re: timing for dd 350

Post by Andrew511 » Tue Oct 08, 2019 8:35 am

unforgiven11B wrote:
Mon Oct 07, 2019 7:24 pm
32* total, vacuum advance disconnect and plug. Get a Mr.Gasket spring kit and toss the lightest springs in it so the mechanical comes in ASAP.
any suggestions ono what to plug it the vac advance with? can I just throw some tape over the hole or is there something I should buy? Does he need the prop installed before he times this correctly?

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John Fenner
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Re: timing for dd 350

Post by John Fenner » Tue Oct 08, 2019 8:53 am

I set total timing propless, don't rev engine too quickly, can break the crank.
I never finish anyth,,,.

unforgiven11B
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Re: timing for dd 350

Post by unforgiven11B » Tue Oct 08, 2019 9:10 am

I’d say the imagination is the limits on what to
Plug it with. Holley makes a plug kit for vacuum ports as do many others. Whatever you use make sure it’s good quality and 100% sealed. Getting a stumble and chasing a vacuum leak swearing it’s another issue will become bothersome !

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keys2pines
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Re: timing for dd 350

Post by keys2pines » Wed Oct 09, 2019 7:35 am

I got the same prop RPM from 32-36* so I left it at 32*, figured it was safer.
12x6'8" Taylor deckover, 383 DD, 72" Sensenich JM
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flcracker9
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Re: timing for dd 350

Post by flcracker9 » Wed Oct 09, 2019 1:50 pm

Mine's set at 32*, no issues
12' Open Palm Beach, IO-0470-L 260hp, 72" NGQ

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