I got my Z back up and running. I have been looking at tuning kits and software online, but I am not sure what is best for me. I want to learn how to tune it myself to avoid all the cost in the future. I plan on buying some sort of OBDII diagnostic software like this

"http://www.obdcom.com"

I like this set up because it comes with a cable and some scan software for a pretty good price. I don't think you can "edit" the PCM with this software, but this is a good place to start in my opinion.

Any advise on this topic is greatly appreciated. This forum has been very helpful to me in the past therefore I wanted to see what you guys think.

FYI the car has had some modifications. They are as follows...

GM Performance 12480002 GM Performance LT1/LT4 Hot Cam Kit
Flowmaster Exhaust
K&N Air Filter
4.10 Gear
2.00 intake valves, 1.55 exhaust valves - Maybe stock? But its my impression these dont come stock on the Camaro. Correct me if I'm wrong please.

 

It looks like that package will let you log data which is crucial if you do your own tuning. One question is how many samples does it take per second. If it's real slow it may not pick up cylinder misfires or knock. Options for doing actual tuning are Jet Dynamic Spectrum Tuner and LT1 Edit for your OBD2 PCM. I have the Jet DST and bought the buggy MXscan software for data logging and I've gotten by with it. I believe MXscan is only available through Craig Moates now.

 

What is a good number for samples for second?

 

MXscan with the Jet DST hardware does about 10 samples/second which seems to work well for me.

 

I think it also depends on the number of parameters you are logging at one time. Less parameters = higher update rates. At least, that's how it seems to work on AutoTap.

I have Autotap(with GM Enhanced parameters) as my scanner and JetDST for my programming software.

 

I never noticed any difference in sample rate due to number of parameters. I wouldn't recommend MXscan since it was basically beta software when I bought it. How do you likke Autotap? I may switch over to that someday.

 

I like it. I just wished it could do things like EFI Live does with logging....that is some nice stuff(but will not work with LT1 systems...well I take that back...some of it works, but the PIDs are hit or miss....).

I could be wrong, but I'm fairly certain I have noticed a resolution increase when I log less parameters. As such, I have a special track config that logs only what I absolutely need to see. I'll try to find a couple of logs that may actually demonstrate it.

 

The car is back firing when accelerating. Its not doing it at idle or when in neutral. ONLY when you are taking off and accelerating.

 

Has it ever run correctly with the hotcam? Is it a new mod? Are you running stock injectors? Are you running stock program? Does it idle "normally" in park or neutral(no bogging, idle searching, etc.)? Manual or automatic?

 

The hot cam was on the car when I bought it. It ran fine then. I don't know if the injectors are stock and I am unsure about the programming. It sometimes idles fine in neutral and sometimes it doesn't. It will sometimes idle high and it will sometimes idle so low it tries to die if you don't give it gas.

 

You mentioned that you just got it running, but was running fine when you bought it, why was it down? What was done to the engine?

You started out with a tuning question and topic, then diverted to a problem. The more information you can give us, the better we can assist. Backfiring can be a number of things, but I'm curious as to what has been done to it thus far.

 

It ran fine prior to that until I lost oil pressure. I pulled the motor to replace the oil pump. It turned out to not be the oil pump, but that's beside the point. The motor is back in place any everything is plugged back up. I started this as a tuning question/topic because I was at first concerned that maybe I cleared the PCM with having the battery was out.

I don't know if I can really give more information... basically its back firing when you are driving, but not in neutral. Sounds like I may have a lifter or two ticking as well, but not sure if that would cause backfiring. If it was a valve problem, wouldn't it cause backfiring at idle and/or driving?

 

I see that you already have a backfiring thread going. If possible, let's keep that discussion in that thread. Injuneer has starting helping you on it and he is one of the best here. I'll read it and see if I can add anything to help.

 

thanks