Chevy 305 Timing Mark Question

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Chevy 305 Timing Mark Question

Postby starfire » Sat Sep 06, 2014 9:15 pm

OK, so there's supposed to be a decal under my hood that shows the timing mark. But there's not. So my question is, which point on the timing thingy is 4 degrees? I've marked the point I think it is with white chalk (well, tried to. It's hard to get my hand down in there and see what I am doing at the same time). Am I correct? Thanks,

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Re: Chevy 305 Timing Mark Question

Postby cjbiagi » Sat Sep 06, 2014 10:29 pm

I think you are correct, the deep "V" notch is TDC I believe and each line is 2 degrees.
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Re: Chevy 305 Timing Mark Question

Postby gerbsinmd » Sun Sep 07, 2014 8:53 am

Unless you are faced with emissions checks, I would advance the timing and make some easy power. I think I am running mine at 12 or 16 BTDC. I really does liven them up quite a bit.
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Re: Chevy 305 Timing Mark Question

Postby starfire » Sun Sep 07, 2014 9:29 pm

Thanks for the confirmation Clyde.
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Re: Chevy 305 Timing Mark Question

Postby cjbiagi » Sun Sep 07, 2014 10:54 pm

I would agree, 4 degrees is pretty low. I would try advancing it more as suggested.
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Re: Chevy 305 Timing Mark Question

Postby gerbsinmd » Mon Sep 08, 2014 9:59 am

I have a pic of my emissions sticker and it shows 6 BTDC for 77 305, but that is still way low. As long as it doesn't ping I would start with 12 BTDC and go up from there.
1999 Saturn SL2
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2008 Town & Country - Family transport
2018 Cruze - 35mpg - avg, 49.7mpg - best so far.
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RIP-2002 Saturn SL2 Commuter car - burned a valve @ 234k miles

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