Getting started with 07 Z06

[Jorday]

I just got my hptuners unit yesterday for my 07 Z.

Mods are cold air intake and kooks headers with no cats.

I have done the basic stuff such as turn off skip shift, adjust the fan settings to my liking and disable the appropriate codes to avoid a MIL as a result of not having cats.

My question is where/what do I begin adjusting for power gains? I'm completely lost, and I haven't found a lot of DIY tuning info for the Z06. Anyone have any suggestions on how I can get started?

[EC_Tune]

Getting a wideband AFR meter is your first item of business. Then try to calm down the OEM Knock controls. They are overly sensitive and pull tons of timing for the littlest knock.

[Jorday]

Getting a wideband AFR meter is your first item of business. Then try to calm down the OEM Knock controls. They are overly sensitive and pull tons of timing for the littlest knock.

OK, how do I do this?

[69redmach1]

what brand intake? Renting some dyno time would probably help too.

[HNK]

Getting a wideband AFR meter is your first item of business. Then try to calm down the OEM Knock controls. They are overly sensitive and pull tons of timing for the littlest knock.

The Knock sensitivity is on all C6Zs or just 07 and later? Can you give some guide lines on how to lessen their sensitivity? I am also getting a KR, spike like, during WOT shifts, is there a way to reduce fix that?

[Jorday]

what brand intake? Renting some dyno time would probably help too.

K&N intake.

[Jorday]

The Knock sensitivity is on all C6Zs or just 07 and later? Can you give some guide lines on how to lessen their sensitivity? I am also getting a KR, spike like, during WOT shifts, is there a way to reduce fix that?

The alternators for 07 had a problem where the stator would contact parts inside and cause false knock. This has been reported a couple of times on the corvette forum.

[atomicfusion]

The biggest way to increase power on the c6 Z (I have done a few now) is to adjust the AFR and increase timing. Different cars like different AFR's and can accept varrying amounts of timing.

First, find a dyno with a Wide band sensor or buy a wide band for the car. Second get a baseline on the car and then adjust the AFR in the MAF HI and Low tables to get the desired AFR.

Then slowly start stepping up the timing advance until stop getting increased hp or start getting knock retard. I like to step the advance by only 1 point and just take it slow. I am usually adjusting the area from around .88 on down and from 3500 rmp on up. Keep smoothing if you can. (cam cars will need more timing down low)

The K&N air filter will need to be tuned first. My K&N produced a completely different AFR than other intakes did, so noone else's MAF tables will be the same for you (others may be close but the dyno or wide band is the best way to tune it)

Also on the K&N look for it to bend down around the clamps. If this happens it will cause a problem with the AFR later and will need to be replaced. (a common problem with these intakes.)

[HNK]

So you keep the PE table the same and just change the Hi and LO MAF tables? Did you tune your car in OL?

Thnx

The biggest way to increase power on the c6 Z (I have done a few now) is to adjust the AFR and increase timing. Different cars like different AFR's and can accept varrying amounts of timing.

First, find a dyno with a Wide band sensor or buy a wide band for the car. Second get a baseline on the car and then adjust the AFR in the MAF HI and Low tables to get the desired AFR.

Then slowly start stepping up the timing advance until stop getting increased hp or start getting knock retard. I like to step the advance by only 1 point and just take it slow. I am usually adjusting the area from around .88 on down and from 3500 rmp on up. Keep smoothing if you can. (cam cars will need more timing down low)

The K&N air filter will need to be tuned first. My K&N produced a completely different AFR than other intakes did, so noone else's MAF tables will be the same for you (others may be close but the dyno or wide band is the best way to tune it)

Also on the K&N look for it to bend down around the clamps. If this happens it will cause a problem with the AFR later and will need to be replaced. (a common problem with these intakes.)

[5_Liter_Eater]

Set the PE to a flat line to make it simple. So command 12.8:1 and tweak the low and high MAF tables until you are achieving what you command. Once you have that you can move the PE up or down on the dyno and see how it reacts at different points in the RPM range.

All WB tuning needs to be done in OL.

[BBA]

Also increase the egine>Airflow>Cylinder Charge Temperature>Filter values up. I do two increments to the whole range and them increase the lower 4 values to make up 50% of the difference from it's initial value to the next higher value.

All LS series engines with the filter setting respond very well to this one change. If you want to be smart about it, do these settings to get the car the way you like it to drive (dramatic effect on engine response) then do the dyno work.

[HA-KSA]

I have tuned a car with exactly similar set up, the job done in the dyno (Dyno Jet) and using the wide band is your best option.

I have adjust the AFR to several point to see what would be the best results i have started with 13 all the way down to 12 for the whole curve using the PE table and MAF hi and low.

The car seems to like more fuel it produces it,'s best number some where around 12.3 and it pulls very hard.

The worst run was at 13 and 12.8 the car produce a lower number than the first run before the tuning.

First run before tuning the car pulls 473 HP and 441 TQ.

I have noticed that the stock AFR set up reach 11.0 at high RPM with the stock tune.

Also the car did not like timing above 20 in the range from 4000 RPM to 7100.

Also when we rev it to more than 7100 no gain.

We ended up with 485 HP and 454 TQ at the last run which it could be a little higher if we have a chance to cool down the car.

Do not take this as a rule because different cars might produce different numbers at different AFR, the above info is exactly what happend with my case.

[HNK]

Were you getting KR above 20 degrees of timing or it just didnt produce power above that? What do you have done to your car? Which fuel grade do you have in KSA?

thnx

I have tuned a car with exactly similar set up, the job done in the dyno (Dyno Jet) and using the wide band is your best option.

I have adjust the AFR to several point to see what would be the best results i have started with 13 all the way down to 12 for the whole curve using the PE table and MAF hi and low.

The car seems to like more fuel it produces it,'s best number some where around 12.3 and it pulls very hard.

The worst run was at 13 and 12.8 the car produce a lower number than the first run before the tuning.

First run before tuning the car pulls 473 HP and 441 TQ.

I have noticed that the stock AFR set up reach 11.0 at high RPM with the stock tune.

Also the car did not like timing above 20 in the range from 4000 RPM to 7100.

Also when we rev it to more than 7100 no gain.

We ended up with 485 HP and 454 TQ at the last run which it could be a little higher if we have a chance to cool down the car.

Do not take this as a rule because different cars might produce different numbers at different AFR, the above info is exactly what happend with my case.

[HA-KSA]

Above 20 degree you can clearly listen to detonation, also if you add that timing and enough fuel to get rid of the detonation, it would not produce any more power, the output still the same.

I always use 95 octan fuel from a pump gas.

[BBA]

Where do you find 95 octane? Is that E85 or something?

[HNK]

Surprising you get knock at just over 20 with 95 Octane. We have 98 here and no knock at 26 degrees. Anyhow, getting that kind of power is great regardless where you have ur timing at.


thnx

Above 20 degree you can clearly listen to detonation, also if you add that timing and enough fuel to get rid of the detonation, it would not produce any more power, the output still the same.

I always use 95 octan fuel from a pump gas.

[atomicfusion]

We use only 94 Sunoco for the cars we have done. My car has been redone now with a large cam. I was at 502/480 prior to the cam and 545/515 after the cam.

I have been getting a lot of help from Brian at Dynotune Motorsports. We set the PE Flat and then tune the MAF to get what the commanded AFR is. Then we just adjust the PE to what we want to command.

We got one car to take up to 29 degrees on 94 and mine took 28 without any KR. We also got the most power at about 12.3-12.4 AFR.

502/480 was a stock motor with CAI, Long tubes, no cats, ported IM and TB and EWP.

545/515 is the same car with forged pistons 11.2:1, cam, lightweight flyweel and twin disk exedy clutch.

[Jorday]

As far as calming the OE knock controls...

Are we talking about the knock sensor initial and minimum levels? They are set to 120 and 50 mV, respectively. What should I change them to?



Atomicfusion,

At what ranges should I try adding timing in the high octane spark advance table? When you say .88 on down, do you mean .88 on down to 0 g/cyl or down on the computer screen which would be .88 and up on the g/cyl scale. Is it worth messing with the low octane spark table?

I guess the thing to do would be add a degree or two of timing and then make record some runs and watch for knock retard? Then, repeat this process until I start seeing knock retard? Is any knock retard acceptable or should I aim for 0.0?

Do you know where and how much I should desensitize the knock sensors?

Sorry for so many questions.

Wasn't there a guy complaining that his car didn't like running a fixed AFR? Like, his car wanted more fuel in the higher gears or something?

I haven't messed with anything that will affect the car's power at this point. I'm just trying to figure out what to try right now. I have run 103.5 in the 1/8 mile and 127.6 in the 1/4. That 1/4 mile mph almost seems low to me for 103.5 in the 1/8...

[atomicfusion]

My car lilked it lean to 4500 then richer on out... I never got 103 in the 1/8th though. 101 was about the best I saw. One of the cars I did went 100 in the 1/8 and 128 in the 1/4. Shifting has a lot to do with that but so does the tune.

As for the knock sensors, I have not turned them down any. I have been scared to do that since my stock bearings were about to go with only 7k miles on the car. I didn't really know until I was building the bottom end, but two were scored really badly.

When I say from .88 down I mean looking down the chart, so going to .88 and bigger numbers.

I didn't change a lot in the below 3000 rpm range though unless the car had a cam.

If you are getting 103 in the 1/8th you should be going faster than 127 in the 1/4 IMO. My car would get knock under load in 3rd gear at the track. Make sure you log an actual 1/4 mile run and you may see that. I added fuel at the knock point to clear the knock. With more fuel I could give the car more timing. I got 1 car to suck up as much as 29degrees with no issues.

[Jorday]

My car lilked it lean to 4500 then richer on out... I never got 103 in the 1/8th though. 101 was about the best I saw. One of the cars I did went 100 in the 1/8 and 128 in the 1/4. Shifting has a lot to do with that but so does the tune.

As for the knock sensors, I have not turned them down any. I have been scared to do that since my stock bearings were about to go with only 7k miles on the car. I didn't really know until I was building the bottom end, but two were scored really badly.

When I say from .88 down I mean looking down the chart, so going to .88 and bigger numbers.

I didn't change a lot in the below 3000 rpm range though unless the car had a cam.

If you are getting 103 in the 1/8th you should be going faster than 127 in the 1/4 IMO. My car would get knock under load in 3rd gear at the track. Make sure you log an actual 1/4 mile run and you may see that. I added fuel at the knock point to clear the knock. With more fuel I could give the car more timing. I got 1 car to suck up as much as 29degrees with no issues.

I'm still not really clear on what needs to happen as far as adjusting the AFR. One of you guys is just going to have to explain it to me like I'm a four year old child.

The car has kooks headers on it now. I gained 2 mph in the 1/8, but only 1 mph in the 1/4 from the headers. It makes me wonder if something is going on up in the higher gears when I'm going down the track. However, it could also just be that maybe the 1/8 mph is reading high or the 1/4 mph is reading low at this particular track or something. Also, I had a Z28 that ran oddly high 1/8 MPHs compared to what it would do in the 1/4 MPH at this same track.

I was going to take the tuner and log some runs with it when I was at the track, but I forgot to grab it as I was leaving the house.

Looking at the stock table for spark advance, are you increasing each value by a set number everywhere from 3000 RPM on up and .88 on down or are you making the values all the same in the area of interest? In other words, did you make it 29 degrees everywhere, or add different amounts here and there to where it was only 29 in some spots?