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Total Timing for Supercharger setup

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Old 04-07-2010, 12:17 PM
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chewy8000
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Default Total Timing for Supercharger setup

I need to figure out how to set total timing with the SC on the 16v at a respectable degree under boost. Here is the equation another rennlister has been helping me with.

TOTAL TIMING
Rear distributor vaccum hose removed = 1.4 degree retard per every 1 psi of boost and I plan on running 6-7psi.

Stock timing is 22 deg, if you retard under boost means total timing will be 14 deg.

So advance total timing to 27 deg to get back around 22 under boost? Is it possible to even get the car to idle at that? All of this is to prevent knock and damage under boost. Definately going to run octane boost or drive down to the race shop for 110.
Old 04-07-2010, 01:20 PM
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pcar928fan
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That race gas will be leaded so BE SURE you don't have a cat on that car or you could burn up the whole thing and you in it...
Old 04-07-2010, 01:28 PM
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chewy8000
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Nope no cat, no emissions. swaintech coated 85-86 manifolds to Y-pipe straight back to the muffler.
Old 04-07-2010, 01:53 PM
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John Speake
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When you reconnect the vac hose, at idle you will recover some of that retard due to the high vacuum at idle giving additional advance..
Old 04-07-2010, 02:48 PM
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123quattro
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It should idle with that much advance. The bigger trick will be starting with more advance. You will probably have to crank a bit longer.



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