Need help tuning spark advance

Well I finally got my ve tables down and want to tune my spark advance tables but have no clue how to... I know how timing works and that it's important to have it dialed in.. obviously I don't have a dyno nor do I have access to one.. which is the best way to start? I'm getting like 40000 knock counts on tuner pro so I think or hope it's false knock.. how could I eliminate that if I need it to tune spark tables?.. my truck is a 94 k2500 stock short block although next week I'm installing a mild cam.. I have vortec heads with a marine intake.. not sure how much work is done to the heads if any but they came from one of my old dirt track racing buddy's.. I have a tpi pump in running 32 psi of fuel pressure if that makes a difference...

Anyone?

There are several bins on this board with vortec head spark tables. When you say 40000 knock counts, are you saying you start out with 40000 or are they continually increasing as you datalog? Here is a thread with the factory spark tables from a L31 (5.7 Vortec ) with the black box pcm. You can use these tables to interpolate a stock spark advance table into whatever mask you are running. http://www.gearhead-efi.com/Fuel-Inj...ec+spark+table A datalog will show where you are getting knock counts and how much timing the PCM/ECM is pulling to stop the knock.
Hope this helps,
Brian

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Originally Posted by sturgillbd

There are several bins on this board with vortec head spark tables. When you say 40000 knock counts, are you saying you start out with 40000 or are they continually increasing as you datalog? Here is a thread with the factory spark tables from a L31 (5.7 Vortec ) with the black box pcm. You can use these tables to interpolate a stock spark advance table into whatever mask you are running. http://www.gearhead-efi.com/Fuel-Inj...ec+spark+table A datalog will show where you are getting knock counts and how much timing the PCM/ECM is pulling to stop the knock.
Hope this helps,
Brian

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Hopefully this log loads up... I took a log earlier while I was driving... some guy gave me a timing table to start at and it ain't worth 2 cents.. it's piss slow with no power tell me what you think by looking at the log..

Can you post your bin file, the adx and xdf you are using? What bin file did you start with?

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Originally Posted by Jwathen23

Hopefully this log loads up... I took a log earlier while I was driving... some guy gave me a timing table to start at and it ain't worth 2 cents.. it's piss slow with no power tell me what you think by looking at the log..

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If its my timing table and its not running well its not the timing table I can tell you that right now. Its been run with very slight tweaks in 4 different Vortec head 350/383 engines with stock/mild cams.

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Originally Posted by Fast355

If its my timing table and its not running well its not the timing table I can tell you that right now. Its been run with very slight tweaks in 4 different Vortec head 350/383 engines with stock/mild cams.

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No it wasn't your timing table.. It was a different one off another forum site.. I'll post the files shortly

This is the timing table I used

Here's my files not my modified bin that's the one I started with

Log isnt that bad BLM wise. It still needs some VE tweaks. Have you verified the timing to be 0 deg with the EST connector disconnected? With the est connector reconnected and error codes cleared, verify the timing at the crank is close to what the datastream shows the PCM is commanding. Vortec heads require quite a bit more AE than TBI heads. There are several threads here on gearhead-efi on tuning for Vortec head swaps. Does it bog or pop through the intake when you stab the throttle? You may also want to try the timing tables that Fast355 has posted here on the forum. They should be a very close to what you are going to need. http://www.gearhead-efi.com/Fuel-Inj...=vortec+timing Post #6 is a start. The whole thread is about timing tables on Vortec heads.

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Originally Posted by Jwathen23

This is the timing table I used

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Honestly its pretty similar to what I run, should be running well with this. Its also pretty similar to what the B-car iron head LT1s run in the 94-96 Caprices and those have tons of power even stock.

Yes it does bog and sometimes it will pop through the intake.. it also has no power at all at wot just before PE kicks in.. it's very flat.. and seems like it's got a miss.. I'll read through fast355 timing.. I had his timing table in until yesterday and switched to the one that a different guy gave me... fast355 timing might have been good because u haven't touched AE at all.. I have the stock timing table in now for the 98 vortec 5.7 and it's alot better then the second table I used

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Originally Posted by Jwathen23

Yes it does bog and sometimes it will pop through the intake.. it also has no power at all at wot just before PE kicks in.. it's very flat.. and seems like it's got a miss.. I'll read through fast355 timing.. I had his timing table in until yesterday and switched to the one that a different guy gave me... fast355 timing might have been good because u haven't touched AE at all.. I have the stock timing table in now for the 98 vortec 5.7 and it's alot better then the second table I used

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The stock vortec table is GUTLESS in my experience.

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Originally Posted by Fast355

The stock vortec table is GUTLESS in my experience.

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What's the best way for me to tweak the stock one to what my motor likes? I hate to have to just copy someone else's or stick with stock I want to learn on my own.. I'll be putting in a cam soon and I'd like to feel confident enough to spark tune it myself

timing can be a real bitch for a beginner, it's really by feel and curvature.

cruising range, just add timing to an area until you reach peak vacuum with a smooth feeling car and stop.

if your timing is too low in a cruise range, exhaust will smell like fuel and car will not run smoothly, and will not make good vacuum.

too much timing, vacuum levels off but engine feels 'strained', temperature goes up in combustion chamber and plugs chop sketchy, and exhaust smells like chemicals. way too much timing, vacuum drops again and you get knocks/pings.

at high vacuum (aka low map) it's safe to add quite a bit of timing, but if your engine doesn't like it, it'll protest by bucking and surging.

at heavy throttle, most people just advance it until you find knock and back it off a couple degrees.. a dyno is ideal, though, since sometimes peak power is WAY before the point of knock, and less timing is way safer than more timing.