Fast,
I often use re-ground camshafts (
http://www.oregoncamshaft.com ), so I'll measure the camshaft to make sure I have a good core. I've only needed to measured a few TBI camshafts. It's been a few years since I last measured a TBI camshaft, but I'm remembering the lift of the three or four I measured was something close to .350 / .380 @ 1.5 rocker arm ratio.
I've used the TBI performance timing table I posted on several different EFI friendly camshaft profiles, up to about .423 / .443 lift @ 1.5 rocker arm ratio. Depending on the vehicle I'm working with, I've needed to make adjustments to the timing table, that's tuning. Camshaft profiles effect cylinder pressures, so there is not a "one size fit's all" performance timing table.
The intent for posting the TBI performance timing table was to help others learn spark tuning by experimenting with a decent / proven timing table to begin with. My method to develop a good timing tables involves using data log analysis with Excel. I use Excel to trend spark advance Kpa vs. RPM vs. MPH. Ever look at Kpa vs. high knock counts?
dave w
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