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Discussion Starter · #1 ·
Ok, this is really, really, really, annoying me!

Ever since the weather has gotten hotter and extremely humid, I noticed the car pinging at WOT. When I'm winding the car up in 3rd or 4th gear I can hear the car rattling (almost as if a screw is lose and rattling), and I can feel the car losing power. When the first happened RichieBrancha and myself went for a ride with his HP Tuners plugged in and could see that my knock sensors were indeed registering knock -- to the tune of 9 on the sensor! So I brought it to TTP and had them strap it onto the dyno and put the car through it's paces. They could see that I was getting knock, and dialed the car down. The car was pulling some MAJOR timing out at WOT (8-9*), and was definately pinging as a result. They also saw that the original tune had 28* at WOT, which they said was much to much. Additionaly, they theorized that since my car was originally tuned in the cold spring weather and in Boston, the elevation and weather changes could be causing the car not to run perfectly. So they edited the tables, and strapped it back on the dyno. The first run netted a little knock (1 instead of 9), and the following 2 runs did not. But the last one did, show a tiny bit of activity on the KS. Overall I was happy, and the car definately felt better.

This weekend, after driving back from Mystic CT in stop and go traffic, when at WOT I could hear the pinging again and the car felt down on power. The car was extremely hot, and I was really flogging it at this point. I am really stumped as to what this could be. I am going to bring the car back to TTP, but was hoping for some input.

The car is an 03 Z with 11K miles on it. Mods are Kooks headers with cats and Vararam intake. TTP checked the exhaust for any leaks or lose stuff and did not see anything.

I was thinking of trying decoking, and injector cleaners, then even throwing some octane boost in the car to see if this is not false knock.

The car runs very strong until I floor it then I feel it slogging.

Thanks,

-N
 

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If you hear the car detonating (pinging) than it is not false knock, if I understand your post correctly.

When you took it to the tuner, what was your A/F and LTFT readings? These will have as much to do with knock as timing. Even in the heat, with 93 octane fuel and a "properly" tuned car you should not be detonating.

Les




Nabbs said:
Ok, this is really, really, really, annoying me!

Ever since the weather has gotten hotter and extremely humid, I noticed the car pinging at WOT. When I'm winding the car up in 3rd or 4th gear I can hear the car rattling (almost as if a screw is lose and rattling), and I can feel the car losing power. When the first happened RichieBrancha and myself went for a ride with his HP Tuners plugged in and could see that my knock sensors were indeed registering knock -- to the tune of 9 on the sensor! So I brought it to TTP and had them strap it onto the dyno and put the car through it's paces. They could see that I was getting knock, and dialed the car down. The car was pulling some MAJOR timing out at WOT (8-9*), and was definately pinging as a result. They also saw that the original tune had 28* at WOT, which they said was much to much. Additionaly, they theorized that since my car was originally tuned in the cold spring weather and in Boston, the elevation and weather changes could be causing the car not to run perfectly. So they edited the tables, and strapped it back on the dyno. The first run netted a little knock (1 instead of 9), and the following 2 runs did not. But the last one did, show a tiny bit of activity on the KS. Overall I was happy, and the car definately felt better.

This weekend, after driving back from Mystic CT in stop and go traffic, when at WOT I could hear the pinging again and the car felt down on power. The car was extremely hot, and I was really flogging it at this point. I am really stumped as to what this could be. I am going to bring the car back to TTP, but was hoping for some input.

The car is an 03 Z with 11K miles on it. Mods are Kooks headers with cats and Vararam intake. TTP checked the exhaust for any leaks or lose stuff and did not see anything.

I was thinking of trying decoking, and injector cleaners, then even throwing some octane boost in the car to see if this is not false knock.

The car runs very strong until I floor it then I feel it slogging.

Thanks,

-N
 

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If your running a stock cam and heads I see no reason what so ever to raise timing to 28 degress at wot. LS6 heads work best with 22. I've tried more on the dyno and have gained nothing. Also what are you running for a injector? You should be running 30's-infact I think 90% of all Z06 should run 30's as soon as they drop in aftermarket intake. Tuning on the dyno is alot different than on the street-your car will pull in alot more air on the street. So if the tuner set your car up at 13.0 on the dyno you could be actually 13.5 on the street-especially with an intake like the Vararam which hardly gets any air from a fan compared to moving down the road. Have you changed plugs at all? I find the NGK TR6's work really well gapped at .040-also did they change your fan settings as well-do you run a colder stat?
 

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Nabbs i thought u had it tuned on the road..dyno tune is fine but u need to tune it on the road :screwy: just not the same plus i hear that ls1 edit is just not the same as HP or EFI we pretty much have the same mods.accept 4:10's :sneaky: and chuck at corvettes-of-westchester did my HP tune on the road and she runs great..your air fuel will be off between dyno and road tune
 

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Discussion Starter · #5 ·
vortech said:
If your running a stock cam and heads I see no reason what so ever to raise timing to 28 degress at wot. LS6 heads work best with 22. I've tried more on the dyno and have gained nothing. Also what are you running for a injector? You should be running 30's-infact I think 90% of all Z06 should run 30's as soon as they drop in aftermarket intake. Tuning on the dyno is alot different than on the street-your car will pull in alot more air on the street. So if the tuner set your car up at 13.0 on the dyno you could be actually 13.5 on the street-especially with an intake like the Vararam which hardly gets any air from a fan compared to moving down the road. Have you changed plugs at all? I find the NGK TR6's work really well gapped at .040-also did they change your fan settings as well-do you run a colder stat?
These are all very good points.

Let me explain -- my original tune was done by SlowHawk when I lived in MA. When I moved back to NYC I noticed some pinging, brought it to TTP. SlowHawk had the car all day, and spent a considerable amount of time tuning on the street. TTP strapped it to the dyno, saw the knock and tuned on the dyno.

The car is stock in every way save for the headers, vararam and cooler tstat. I am still on the stock plugs and wires.

It seems to me that the way to solve this would've been for TTP to street tune as well as dyno tune the car. Even on the dyno the KS' were going off a tiny bit on a few of the runs. I believe the AFR was dead on while on the dyno -- but it could be vastly different on the street.

I'm hoping TTP will step up to the plate and street tune it. Will let everyone know what the outcome is.

Thannks,

-N
 

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Nabbs said:
These are all very good points.

Let me explain -- my original tune was done by SlowHawk when I lived in MA. When I moved back to NYC I noticed some pinging, brought it to TTP. SlowHawk had the car all day, and spent a considerable amount of time tuning on the street. TTP strapped it to the dyno, saw the knock and tuned on the dyno.

The car is stock in every way save for the headers, vararam and cooler tstat. I am still on the stock plugs and wires.

It seems to me that the way to solve this would've been for TTP to street tune as well as dyno tune the car. Even on the dyno the KS' were going off a tiny bit on a few of the runs. I believe the AFR was dead on while on the dyno -- but it could be vastly different on the street.

I'm hoping TTP will step up to the plate and street tune it. Will let everyone know what the outcome is.

Thannks,

-N
Hey Nabbs,

If you can't get a good tune from these guys contact FRC Tom. He can put it right for you. You can mail him your PCM and tell him your mods. He did my car at the fest last week, and it is a lot better. Don
 

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I have found that tuning for knock on the dyno for max timing produces knock on the street. The load is not as great on the dyno. A head and cam car with a CR above 10.6 usually takes no more than 20-22 on top. You are probobly knocking under load in the 3600-5000 rpm range also.
 

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Discussion Starter · #8 ·
FRC Tom said:
I have found that tuning for knock on the dyno for max timing produces knock on the street. The load is not as great on the dyno. A head and cam car with a CR above 10.6 usually takes no more than 20-22 on top. You are probobly knocking under load in the 3600-5000 rpm range also.
That's good info to know Tom, and yes that is exactly where I can see the KS' going off.

I am a little disapointed with TTP since I have not heard back from them. Luckily another local tuner has offered to look at the car free of charge, so hopefully this story we'll have a happy ending.

I was hoping that TTP would have contacted me since I called them and offered to schedule some time to fix what is most likely a tuning issue. I am sure that they do great work (and I have spent almost $2K on them since I've had my Z06), but right now I am very disapointed with their customer service.

Does anyone know if there is anything maintenance-wise I should be doing? Should I be doing any injector cleaning or decoking?

Nonetheless, I refuse to pay for a 3rd tune!

-N
 

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Excellent advise Tom ... BTW I got so wrapped up with the racing Friday I forgot to take you up on your offer to autotap my car - next time my friend ...

Les


FRC Tom said:
I have found that tuning for knock on the dyno for max timing produces knock on the street. The load is not as great on the dyno. A head and cam car with a CR above 10.6 usually takes no more than 20-22 on top. You are probobly knocking under load in the 3600-5000 rpm range also.
 

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Sounds like another TTP horror story...who tunes on a dyno anyway? I had a similiar problem with another popular PA vendor not on this site...everyone with LS1edit is a master tuner.

Find a shop that tunes the car entirely on the street and when finished dyno's the car for numbers...

Tell TTP you want your money back and mention the BBB...this is just wrong.

Bill
 

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Hey Nabbs, i haven't seen anything added to this post in awhile just wondering if you were able to take care of your problem. I saw your car @ corvettes-of-westchester last week(QS Z w/ ZOSIKZ plate is mine)...just wonderin if chuck was able to take care of the problem......he tuned my cammed z a few weeks ago for me and i'm defintley extremely happy with it
 
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