fishmasterdan

I want to give thanks to John for helping me along. I would have never gotten this far with out him.

Ok Please take a look at this timing table. I am not sure what to what to adjust here. What am I supposed to be looking for as far as timing goes. This is a purchased tune.
Dan

Grim Reaper

I doubt many cars can use that table without detonation occuring.

It's quite high in the higher rpms and below 85 kpa. Even in a VERY lean Highway Mode setup, that total spark advance below 55kpa is over 48*. At that level, you are approaching the limit where "cross-firing" to the wrong terminal in the distributor cap could occur. If it were not for the small amount of advance built into the distributor, anything above 45* would fire backwards to the previous terminal.

This would need a functioning EGR for those spark advance values to work. And the highest octane of gas possible, probalby 94+. If you have a functioning EGR, I would limit the maximum in the "MAX SPARK ADVANCE" constant to 43* and then work with the spark table from there: slowly increasing the MaxSpark until you find knock occuring....or continue decreasing the MaxSpark until it goes away.

If you do not have a functioning EGR, you may need to decrease your max spark advance to 38* as your starting point.

fishmasterdan

I do have a an EGR. I dont here any pinging/knocking unless I start going up a hill and need to really get on the gas. It is supposed to be set up for towing. I will do what you said and try that.

91chevz71

dYeah, that's too much. I originally had a table that had alot of timing (almost that much), but removed 3-4 deg across the board and my truck runs better.
Rbob said it- does the engine make a lot of noise, with little power? I was like, yeah...it does! too much timing. Even though it doesn't knock/ping, it still is too much.

fishmasterdan

It does make alot of exhaust noise but the power seems good.

Do you have to enter a new number in every cell??

91chevz71

here're my latest spark advance tables

Grim Reaper

Unfortunately, you don't disclose your exact setup, nor what tuning tools you are using.

If you have a scan tool, note the rpm & MAP readings when the ping occurs. Also, depending on what calibration you are using, you may even be able to see when inaudible knock is occuring. This typically begins before audible knock occurs and is often an "early warning".

If you don't have a scan tool, consider buying one. It's a "must" if you are tuing.

The good news, its all "fixable". It just takes a little time and effort.

fishmasterdan

Does your motor have an aftermarket cam in it? I am thinking it was tuned this way for my cam?

fishmasterdan

Well lets see
Ok 5.7 chev 95 yukon
New throttle body and 1" spacer from here
http://www.rvmorsemachine.com/
Intake was bored to match the throttle body
New Comp cam 12-249-4 specs are here
http://www.compcams.com/Technical/Se...umber=12-249-4
New 1.6 roller rockers
New tune from tbichips.com
K&N air filter
New air intake from here
http://www.cfm-tech.com/catalog/air_...uck_549430.htm
New cold air tube from here
http://www.cfm-tech.com/catalog/air_...___3280272.htm
160 or 170 degree t stat (cant remember exactly) came with the tune.
New high flow water pumps
New long tube headers
New 3" exhaust (no cats shhhh)
New 4 wire O2 sensor
New IAC
New plugs and wires
New Timing chain
New High flow oil pump.
Picked up an ALDL cable and doing some data logging with ttdatasystem (cant rember if that is the exact name or not)

fishmasterdan

I am not against buying some sort of scan tool but when I data log I only get a few knocks on the knock count?

fishmasterdan

Well shoot all was going well than all of a sudden the check engine light came on and it went inot limp mode. Now I cant get the moates memcal adaptor to work. I had to go back to the old tune.

Any way to erase the stock chip while it is in the memcal? I tried to erase it with a Burn1 chip burner but it wont erase.
I am using 27sf512??
95 yukon BJYL ecm