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  #31 (permalink)  
Old 07-25-2012, 09:31 PM
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Will disconnect my other vacuum accesories and dedicate the vacuum advance line.

The curve selected is F . I have 5 degrees twisted in with the light. Plus the 10 from the F curve is 15 inital. Then starting at 1200 by 3000 rpm adds 20 , totals out at 35 and stops. Vacuum advance is curve 1. Dials set at 0 and 6. limiter is at 5500. Govenor at 5200 shifts. That is how it sits , unless you have some other suggestion.

When it was locked and verified at 35 no vac advance , that felt good. Have not jetted secondaries to .107 yet.

The choke door has also been wired open in case it was sucking closed.

Will return with more results.

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  #32 (permalink)  
Old 07-25-2012, 09:41 PM
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35 degrees timing is too much under WOT boost.
You need the BTM spark retard box to do that. or more than street octane gas.

Limit timing to 30-32deg under boost. 34 degrees is really pushing it.

more initial at idle short advance curve 30-32deg total @WOT under boost

then monkey with the vac advance.

you are tuning by seat of the pants feel. That does not work.

You need to establish the correct timing under boost, under load (with correct {rich}WOT jetting {what the engine wants,not what a afr gauge says})
you need a way to measure real engine power, under boost.

a long hill is nice. A drag strip is even nicer. Seat of the pants evaluation will get you a damaged motor and will not
get you to real max performance.

After finding the best reliable power timing under boost and correct rich WOT jetting , using locked timing, I would use a 15deg advance curve
and some vacuum advance. I,J,K,L and 3, 4 or 5. go easy on the spark advance under boost untill you can get the BTM

Last edited by F-BIRD'88; 07-25-2012 at 10:07 PM.
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  #33 (permalink)  
Old 07-25-2012, 10:00 PM
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The hotter the weather gets and the harder.longer you run hard (like up a hill or towing) under ooost and the hotter the blower gets the more power and reliabilty you gain from using water methanol injection.
On a hot blower than runs hard it not only reduces knock and allows more timing
it increases power under boost by increasing air charge density (intercooling)
Makes more power from each # of blower boost. Ya get more go for your 5psi.
The harder and longer you run (like a truck does) the more effective it is.
The water methanol injection allows you to run under boost without such over rich WOT jetting. "overfueling"
You save on fuel, over time.

Your blower will get hot and conditions do get hot.
Water methanol injection is a real good investment.
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