is this a normal-looking stock spark table for a swirl port iron head tbi?
pretty sure my table configuration is correct, just never seen one like it.
why is there 8-10 degrees less timing than makes sense, then they just throw it back in?
insight?
i have a california emissions spark table for the same engine and it's stranger still...
Quite frankly does not surprise me at all!!
These are actual CCC Q-Jet tables for the L69 in a Monte Carlo
And an 83 G20 Van, notice there is an 8* reduction between 2,400 and 3,000 @ 80 KPA.
Finally a LG4 in a GrandPrix
Last edited by Fast355; 07-03-2014 at 02:53 AM.
Based on the looks it seems like some kind of emissions maybe even mileage reason for less timing at part-throttle. I was shocked at how much cruise timing the fullsize G20 van had with the LF3 engine. I used a slightly tweaked version of that spark map with my TBI setup and later TPI setup with alot of sucess on my 83 G20 Van.
haha yeah, thanks, i guess compared to some other weird stock bins it doesn't look that odd
it's just kinda weird, it isnt even part throttle range, it's almost impossible to get there without being in power enrichment.. but then they throw a TON of timing in in higher map?
since i cant see any logic to it, i'll just roll my own..
Early calibrations were field developed and often don't look as nice or neat as the simulation based maps of today.
thinking of throwing something more traditional at it like this, bad idea?
doesn't look like a bad place to start.
1995 Chevrolet Monte Carlo LS 3100 + 4T60E
Posting Permissions
Reply With Quote
Bookmarks