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Discussion Starter #1
So you make max power and then ping? or there is the correct timing , then you lose power , and then ping? I know that sounds weird, I'm just trying to figure out why my boat likes so much timing. I went out sunday and was running 42* and couldn't decide weather to turn the timing up or down.
 

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The amount of timing depends on the motor combination and what it wants, a lot of variables there, as far as ping goes that all depends on the compression you have and what octane fuel you run, the more timing you run the more octane you need!.. Are you sure it likes 42*???, might want to check your timing marks to TDC!...
 

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Do you have a electronic timing light you can Zero out ? I have to think your marks aren't correct. But you never know.

Sleeper CP
Big Inch Ford Lover :D
 

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So you make max power and then ping? or there is the correct timing , then you lose power , and then ping? I know that sounds weird, I'm just trying to figure out why my boat likes so much timing. I went out sunday and was running 42* and couldn't decide weather to turn the timing up or down.
1) What altitude do you run at?

2) Could your mixture be fat?
 

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Read your plugs - tiny shiny specs is aluminum from your piston being lifted off. Black pepper marks will usually be seen first. Use a magnifying glass and bright light. Without bright light + magnifier you may not see the aluminum specs.

42° sounds like a BBC with OEM heads and a good sized dome. Yes/no ? Race gas ?

Typically most will start timing on a BBC around 35°-36° degrees and then work their way up. Each degree up you must note the performance and read the plugs !
 

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make sure your balancer hasnt slip on itself;)happened to me before and the timing maks are way off:D


best thing to do is find t.d.c and look at your timing tab with realtion to your balancer marks,if its dead on then hell if i know,lol!!!!!!42 sounds way to high for bbc even with aluminum heads.:)bulbbut there have been weirder things before,good luck and i hope you can figure it out.travis:)hand
 

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Discussion Starter #9
Thanks guys..I was just curious from you guys with some dymo experiance, on a given motor as you increase the advance will it make max power right before she goes or will you lose power for 1 or 2 or 4 * then ping. As far as my specifics. I haven't verified the mark with a head off or anything but pulling #1 it seems to be tightest around 2*btdc, I'm not sure if that means I'm really at 40* or 44*. Plugs don't seem super fat..no specs, I'll no more next time out because I'll have my dry headers with an a/f in them. The reason(s) I think it likes so much advance are: altitude(4500ft) open chamber alum heads, I'm mixing 110 and 91 as far as fuel goes.
 

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Thanks guys..I was just curious from you guys with some dymo experiance, on a given motor as you increase the advance will it make max power right before she goes or will you lose power for 1 or 2 or 4 * then ping. As far as my specifics. I haven't verified the mark with a head off or anything but pulling #1 it seems to be tightest around 2*btdc, I'm not sure if that means I'm really at 40* or 44*. Plugs don't seem super fat..no specs, I'll no more next time out because I'll have my dry headers with an a/f in them. The reason(s) I think it likes so much advance are: altitude(4500ft) open chamber alum heads, I'm mixing 110 and 91 as far as fuel goes.
When you are checking timing are you doing it at idle, above idle or at the highest rpm you run at?

Typicly a lower output/lower compression engine will lose power due to excessive timing long before it kill's itself. The higher the output (work) the quicker it happens. Our engines being limited to 12:1cr will lose significant power before destructing. Back in the open compression days (16:1 +cr) they would run the best right up to the point of melt-down.
 

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When you are checking timing are you doing it at idle, above idle or at the highest rpm you run at?

.

Try setting the timing at 3,500 or 4,000 while on the water.

Even with out the timing light,before we put the crank trigger on, at 3,500 or 4,000 you could hit the sweet spot by just turning the distributor as we ran up river.

Sleeper CP :D
 

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Most of our BBC/SBC racing engines liked 40-42* total advance. These were basic roller cam, 13.5-14:1 CR, conventional head, drag race engines. Most were sorted out on the dyno, all had TDC checked while being built.
Our most recent engine, again a BBC 14.5:1 CR, roller cam, conventional head deal made the most power at only 36* total. First conventional head engine I've ever tested that liked less than 40*... Live an learn I guess.
 
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