Info on tune

[davej]

I'm an old guy whose definition of a tune is plugs, points, timing and carb adjustment. From reading many posts about tunes I think a tune on a Z is mostly done with a computer, but unsure about how and what is done. I wonder if someone can explain in more detail what takes place when you have your Z tuned. Also where can you get a tune, how can one tell if the tuner is qualified to do the work. Thanks in advance.

[mmarx82]

It's best to go with reputable tuners, start with the companies on here that others are talking about. For Example Ted Jannetty with Jannetty Racing is who I'll be getting to do my tune. I'm not sure of any reputable places in SC but someone here on the thread might know. There are two ways to get your tune's done:

1. Dyno Tune, you take your car to a reputable place and they dyno it. Then based on the modifications to your car they adjust settings that are in the ECM to get you even more Horsepower and Torque than you had before by changing your spark curve and other settings. They can even remove your car's speed and RPM limiter. A tune can help even with no mods changes to increase your HP and Torque. If you have an Auto you can even change shift points.

2. You buy a programmer like this one that plugs into your OBDII port and get one of these same companies to do a "mail in" tune. The process works by first sending them your stock tune, doing some datalogging on the programmer and sending them that as well. Then they send you back a custom tune to load into the ECM. Afterwords you will probably do more datalogging and send that back to them to verify that all looks good or receive another tweaked tune.

[x2martell24]

Originally Posted by davej

I'm an old guy whose definition of a tune is plugs, points, timing and carb adjustment. From reading many posts about tunes I think a tune on a Z is mostly done with a computer, but unsure about how and what is done. I wonder if someone can explain in more detail what takes place when you have your Z tuned. Also where can you get a tune, how can one tell if the tuner is qualified to do the work. Thanks in advance.

If you are even considering doing a computer tune; which is what is done on the ECM for the ZL1, you need to talk to TED JANNETTY!!! He is the best there is and more than qualified to do the flash tuning with a hand held tuner. He can mail you the tune packages and the first tune is FREE if you buy the parts from Jannetty Racing.
I don't work for him or anything.... dont worry. I have just had a lot of experience with his tuning and the quality he and his employees have always provided.

Go that route.... you will NOT be disappointed.

[gen=5]

YOU can do mail order tune,if your ZL1 is either stock or just has mild bolt on's most places can do mail order.
All that is really done if you want the truth that control HP only is they reduce the amount of fuel the injectors give the motor by controlling the dwell timing(fuel jet and metering rods) (on & off),then they increase the amount of timing the computer givings the system based on many inputs(turning the dist while and after vac connected to vac advance)...other stuff is seat of pants feel which is like shifting.(amount of vac going to trans module)I hope comparing older cars helped you understand it...
Now if they send you a programmer, you yourself can control inputs like trans shifting,how hard it shifts,the speed limiter,the tire size,and a few other options..I think its always best to get a programmer so you have control of these things at anytime you want instead of emailing back trying to change those simple things till you like it...different shops may have a little bit different tunes. If you purchase the tune from the programmer company themselves you never have to worry about have issues with the tune as far screw ups as they are normally are the first to get the information since they pay the big sponsor dollars.
Now if your going to go ahead and do big mods that include going ahead and opening up the motor then you need to find a good shop that's done it lots of times and has a package they have had lots of luck with.
Find others that have used a shop that they can tell you about and show you their car, not what they have heard about or seen driven on youtube...
I for one would tell you to call fastlane here in houston they did my car,and have always had lots of ZL1's on the lot as well as CTs-v's ZR1's and install that crate motor in lots of older cars to make custom cars for Sema...
Now they are not the only one there are lots of other shops around,but i have not used them for my ZL1,I have used Hennessy for my VIper,as well as others like MTI before Jason closed down in 2005 he built me 3 cars and lots of other things over the yrs,I have used and know herb Adam's from yrs of living in monterey and racing out there on the road course in my 68 firebird...
your going to have to find someone and start a relationship with them,and try to stay with them so all of your project is under one house,and well controlled if your start a bigger project than just bolt on's....good luck...
Also you need to find someone that has a big enough on line sales that they can offer you a competitive pricing so your not over paying for what you get...Its the reason I went to fastlane and stop using another shop here in houston they match every price i found and didn't have to pay shipping costs when they went to free shipping...
There are lots of shops that will do that for you if they want your business and dont treat you like they have gotten too big for they own benefit like Walmart used to do until they woke up,lol....now you can just show walmart your phone and a price from some place else and they match it.
I know its a lot to read but I hope it helps you..

[hognutz]

tuning on an old car is very mechanical. IE carb size, carb jetting, timing advance. you add more power you have to adjust these parameters with new parts an changin your timing.

on a computer controled car you have sensors that take in all this information and then tell the fuel injectors how much fuel to add or the distrubutor how much timing to add or pull based on real time conditions.

so when a tuner is tuning the car he is just calibrating the computer based one the new variables. They just plug into your ODBII port and flash you computer with a new file. if you go too far you will need new parts like injectors or larger TB.

no different that on a carb you can add jetting but as some point would need more CFM. you can also mechanical add more timing or setu up the distributor to have more advance.

So just like if you used to tune you own cars you wold play with these parameter to get the car to run right. On a new car you will interface with the computer to ajust this stuff.

One thing I have noticed is people thing there is a larger differnce than there is you really are ajusting the same stuff just in a different way. Computer tuning for real world is way better becaue it adapts to temperature, altitute, load things like that real time.

an old mechanical tune only works well when engine is up to temp, at the altutude it was tuned for, in the temperate that it was tune for. outside of those it is always out of tune.

now finding a good tuner is pretty easy with the internet there are very large companies that will tune nation wide and then usually depending on where you live there will be local guys that know what they are doing.

if you are computer savy at all just use a good online company that will update tunes for fee so you don't get eaten alive in tuning fee's. If computers are a bit much for you I would find a local shop to just dyno tune your car.

[LS1 Fun]

I am highly against Mail Order tunes, and would recommend you find someone local who will tune the car on a dyno. Maybe go on a local forum and ask where everyone goes or go to a local meet and talk to different people.

A mail order tune may be cheap and convenient, but it is a guess at best as every car reacts different to mods. What might work for one car may not work for someone else since there are so many variables involved in the tuning process, and this can only be properly addressed with a live person reading the data from your car off a dyno and tuning accordingly.

Some of you may be comfortable with a mail order tune and say the car runs just fine with one, but I bet if you had a reputable tuner look at the tune on a dyno you will be suprised at how off it really is.

[HDRDTD]

Originally Posted by hognutz

tuning on an old car is very mechanical. IE carb size, carb jetting, timing advance. you add more power you have to adjust these parameters with new parts an changin your timing.

on a computer controled car you have sensors that take in all this information and then tell the fuel injectors how much fuel to add or the distrubutor how much timing to add or pull based on real time conditions.

so when a tuner is tuning the car he is just calibrating the computer based one the new variables. They just plug into your ODBII port and flash you computer with a new file. if you go too far you will need new parts like injectors or larger TB.

no different that on a carb you can add jetting but as some point would need more CFM. you can also mechanical add more timing or setu up the distributor to have more advance.

So just like if you used to tune you own cars you wold play with these parameter to get the car to run right. On a new car you will interface with the computer to ajust this stuff.

One thing I have noticed is people thing there is a larger differnce than there is you really are ajusting the same stuff just in a different way. Computer tuning for real world is way better becaue it adapts to temperature, altitute, load things like that real time.

an old mechanical tune only works well when engine is up to temp, at the altutude it was tuned for, in the temperate that it was tune for. outside of those it is always out of tune.

now finding a good tuner is pretty easy with the internet there are very large companies that will tune nation wide and then usually depending on where you live there will be local guys that know what they are doing.

if you are computer savy at all just use a good online company that will update tunes for fee so you don't get eaten alive in tuning fee's. If computers are a bit much for you I would find a local shop to just dyno tune your car.

Finally someone actually answers the OP's original question.

Thank you.

[davej]

Thanks to all of you I have a better understanding of a tune. Enough to know that when I do have a tune to let someone else do. Maybe Charlotte or Atlanta will have a competent tuner I can hook up with. I'm glad this forum exists since I have gotten more information from here than any dealer could provide.