[AdamIsAdam]

I'm also running a 160 hi flow. It runs about 165 in most weather. In hot summer days, it's usually 175-185. On highway with high RPMs, it'll creep up a bit to 195, but comes right back down as RPM's drop.

In winter, it stays 160-165*.

[HWYSTR455]

Originally Posted by AdamIsAdam

I'm also running a 160 hi flow. It runs about 165 in most weather. In hot summer days, it's usually 175-185. On highway with high RPMs, it'll creep up a bit to 195, but comes right back down as RPM's drop.

In winter, it stays 160-165*.

How much vacuum advance do you have adding? As the throttle blades open, vacuum drops, like at highway speeds with a little gear. = less advance at highway speeds. This is a perfect example of how a programmable timing curve can help.

I know there's controversy regarding manifold vs ported vacuum, and how much advance to run at idle, but there certainly is a direct correlation to temps. Look at factory base/idle timing and how it changed over the years, and ask yourself 'what if' you run more at idle and restrict total to compensate.

Also compare those base/idle timing numbers to when the factory switched from manifold to ported.

Now add how gas has changed and cam profiles. Not to mention many aftermarket distributors only provide a total of 20-24 degrees of advance.

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