Guys,

I need some help on this data log of my CC503 tune.

I posted up a thread on the car running 20* hotter when doing ANY steady cruising at all. The cooling system is solid. I can find no problems with it whatsoever.....so that leads me to the tune. Can you guys look over this log and see if it's too lean or if the timing is screwed?

I have highlighted and made notes where I was cruising, having cam surge, and one WOT run from the bottom of second to the top of third.

I do have one old log I made of my stock setup and the engine coolant was a reported 190* the entire time I was cruising at light throttle.....the timing looks to be higher too....in the 40's compared to much of the 30's I see below.....

Also you can see the temps like to hang around 207* and gets as high as 212*when cruising. The car has never done this before. I really think that something is jacked with the tune to cause my heating issue.

http://www.ace1252.com/ACE1252_CC503_1996_Z28_Log.xls

Any opinions are much appreciated!!!

 

Glad to see im not the only one trying to do their own tune these days.

First of all, Im dealing with the same issue on my car right now... however since I am away from my car at college - my trial and error process has been very slow. If you have instant messenger feel free to hit me up and maybe we can collaborate a little.

To answer your question, I do believe you have answered it yourself, so good job In the reading I have done, I have learned that the more spark advance you have (until the optimum spot) the cooler your engine runs, and therefore the less advance you have the hotter your engine will run. A 10 degree drop in timing from what it used to have is significant to cause that increase in temperature, so you need to figure out why your PCM is doing that. Since I am in the same boat as you right now, ive got a couple things in mind I plan to try the next time I go home. Like i said, hit me up on aim and maybe I can help you out.

 

Well, I started out by purchasing a tune.

Now, I'm starting to dive into what it takes to get this thing right.

It's not that the car drives horrible....it idles well and does feel strong....however I don't like how when cruising that the temp goes up, up, up, up. I'm also having issues with some wicked cam surge around 7-10 mph at times.....I mean some very mean bucking. I think the purchased tune is in the ballpark.

Once I can get a few opinions on this log, my plan is to purchase OBDII tunercat and start looking at the program compared to my stock PCM's program(I have two PCM's...one with the CC503 program and the my original with the stock programming).

I may start out by just changing the injector constants to 30# in the stock PCM and see if the temp returns to normal. I know it will idle rough and will be rich....but this will give me good data to know if the present tune is too "hot".

In looking through the programming forum, I did find this.....
http://www.bfranker.badz28.com/LT1Edit/LT1files.htm

Which came from here.....
https://www.camaroz28.com/forums/sho...light=LT1+tune

Here is another article....
http://www.lt1howto.com/articles/pcmtuning.htm

I plan on looking though the hotcam tables to see what it looks like....since the hotcam is very close to the CC503.

 

something is wrong if you have mean bucking with a 503, and it should not be warming up like that. My car hardly has any buck at all even untuned. (granted different cam) It only does it in first gear at closed throttle for the most part. Who did you purchase the tune from? I wouldnt be satisfied with that product at all.

 

I'm not totally dissatisfied with the tune. It idles well and pulls strong at WOT all the way to my shift point of 6200(limiter set for 6500). It has picked up 0.3ths and 3.5mph in the 1/8th from my baseline runs.

I just have the bugs of the heating at cruise and the minor cam surge.

I'm not going to mention in open forum who tuned it, but needless to say, support has been very slow. Knowing that life can knock us around without warning, I'm trying to have some patience and not email the heck out of them.

However, I am trying to get help from other sources.....one of them is here....

 

Any other comments on this? Does the Ignition timing look too aggressive?

Here is a complete list of what was changed/upgraded on the car.....

• Opti(brand new AC Delco unit from Summit)
• Water Pump(brand new from Summit…not rebuilt…. w/180* thermostat)
• 2 New precat AC Delco O2’s(they are the “new” style…has a different cage around the sensor)
• New Knock Sensor(torqued to spec)
• New oil pump drive gear
• New lifters and guides
• New valve seals
• New valve cover seals
• Red power coated valve covers!!! Looks nice!!!
• Replaced rear crankshaft seal
• Replaced Oil pan gasket
• Replaced all timing cover seals
• New stock timing set
• Installed white oil pressure spring
• 7.2” chromemoly pushrods
• GM guide plates
• 1.6 rockers Comp Pro Mags
• CC503 Cam
• 30# SVO injectors

Injuneer: Am I in the wrong spot for this question? Does it need to be moved to the Computer/Tuning forum? Please do if you feel it's necessary.