Do I need a tune?
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 4,002
Likes: 1
From: It's warm in Fla!
CI 6-7-8-9-10-12 Veteran
St. Jude Donor '11
Do I need a tune?
If I'm installing headers, x-pipe, hi-flow cats,Vararam intake, spacer, and 160 t-stat... do I need a tune?? With most tunes running around $500.00 how much benefit can I expect? Should I wait until I add a cam and heads? Inquiring minds want to know 
Kevin
Kevin
Eccentric Member
Joined: Feb 2005
Posts: 25,508
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From: Like Anyone Could Even Know That! Florida
Cruise-In VII Veteran
St. Jude Donor '05-'06-'07-'08-'09
Kevin .. you will reap the most benefit from your mods with a tune. You are close to Mike Norris, who many say is a great tuner.
Racer
Joined: Mar 2006
Posts: 331
Likes: 0
From: Philly Pa
Just got a tune from COW. I don't know why someone would need more than car than what I have now. Fast push back in the seat. It didn't do that before the tune. Headers cats blackwing intake Rt.66
I'm not doing anything else to the car.
I'm not doing anything else to the car.
Safety Car
Joined: Jun 2005
Posts: 4,905
Likes: 569
From: Bucks County PA
I am going back tomorrow to get my Tune adjusted.
The stock tune would run good, but a custom tune can:
1 - Clear any codes that might pop up due to the headers
2 - Delete skipshift on manual trannies
3 - Turn your fans on earlier for your 160 stat
4 - Raise your rev limiter a bit
5 - Reduce Torque Management
Howard
The stock tune would run good, but a custom tune can:
1 - Clear any codes that might pop up due to the headers
2 - Delete skipshift on manual trannies
3 - Turn your fans on earlier for your 160 stat
4 - Raise your rev limiter a bit
5 - Reduce Torque Management
Howard
Safety Car
Joined: Dec 2004
Posts: 3,565
Likes: 5
From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
i wouldn't worry about tuning it until you are more or less done with the bolt-ons.
i've had my c6 since nov. '04 and still have yet to get it tuned.
it has been my understanding that the ecm is programmed in such a way that it will 'learn' or 'self-adjust' to a degree.
most minor mods. can be compenstated for by the 'learning' process. even after a tune the computer will continue to learn. a good tune one day on dyno does not garantee the same results six months and a season change later.
i've had my c6 since nov. '04 and still have yet to get it tuned.
it has been my understanding that the ecm is programmed in such a way that it will 'learn' or 'self-adjust' to a degree.
most minor mods. can be compenstated for by the 'learning' process. even after a tune the computer will continue to learn. a good tune one day on dyno does not garantee the same results six months and a season change later.
Le Mans Master
Joined: Oct 2005
Posts: 5,052
Likes: 889
From: Tampa Florida
Originally Posted by Zig
i wouldn't worry about tuning it until you are more or less done with the bolt-ons.
i've had my c6 since nov. '04 and still have yet to get it tuned.
it has been my understanding that the ecm is programmed in such a way that it will 'learn' or 'self-adjust' to a degree.
most minor mods. can be compenstated for by the 'learning' process. even after a tune the computer will continue to learn. a good tune one day on dyno does not garantee the same results six months and a season change later.
i've had my c6 since nov. '04 and still have yet to get it tuned.
it has been my understanding that the ecm is programmed in such a way that it will 'learn' or 'self-adjust' to a degree.
most minor mods. can be compenstated for by the 'learning' process. even after a tune the computer will continue to learn. a good tune one day on dyno does not garantee the same results six months and a season change later.
When I had the VaraRam installed, it seemed like it took a day or two to respond and it was amazing. Zig, you do have a point. Many members have not had a tune and their car runs fine. But there are benefits to a tune, it's just the fact of paying $500 for it. Is it worth it is the question?
Safety Car
Joined: Dec 2004
Posts: 3,565
Likes: 5
From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
Originally Posted by Fore58
... there are benefits to a tune, it's just the fact of paying $500 for it. Is it worth it is the question?
a good tune is worth it. the cost/gain is about the same as headers, cam, rockers, etc. it just depends upon the 'tuner'.
personally, i've never been able to get the 'perfect' tune the very first time.
imo, the good base tune could be obtained with a bit of patience. If one was to connect a datalogger and just let it collect for a week or two. during the collection process a number of wot runs, traffic driving, idling, short high-rpm bursts, prolonged high-rpm use, etc. etc. by analyzing the 'data' (including weather conditions/temp., coolant temp, iat, oil temp, engine performance, a/f, etc., etc. etc.) one should be able to get a pretty good base tune. i say base because the ecm is still gonna self adjust based upon the newly tuned 'base settings'.
but until i get my hands on some 'tuning utilities' i'm just gonna let the computer tune itself, until i get radical with it, that is.
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Drifting
Joined: Jul 2003
Posts: 1,796
Likes: 1
From: Annandale VA
Zig, you need to talk to someone who has actually used Autotap, EFI Live, or HP Tuners to log ECM data on the street. You cannot turn it on and record data for weeks on end, days on end, or even hours or minutes on end. Depending on how many parameters you are logging, you will fill up your disk in nothing flat, and end up with a huge file of data that is almost impossible to decipher.
What most guys do is focus on one aspect of their tuning at a time. For example, if you are trying to tune for cruise efficiency, you might log your fuel trims at a constant cruising speed or constant throttle position, then change one parameter, then make a second log at the same speed or TPS value. That way you can see the effect that your change made.
It's slow, painstaking work.
What most guys do is focus on one aspect of their tuning at a time. For example, if you are trying to tune for cruise efficiency, you might log your fuel trims at a constant cruising speed or constant throttle position, then change one parameter, then make a second log at the same speed or TPS value. That way you can see the effect that your change made.
It's slow, painstaking work.
Safety Car
Joined: Dec 2004
Posts: 3,565
Likes: 5
From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
Originally Posted by HITMAN99
Zig, you need to talk to someone who has actually used Autotap, EFI Live, or HP Tuners to log ECM data on the street. You cannot turn it on and record data for weeks on end, days on end, or even hours or minutes on end. Depending on how many parameters you are logging, you will fill up your disk in nothing flat, and end up with a huge file of data that is almost impossible to decipher.
What most guys do is focus on one aspect of their tuning at a time. For example, if you are trying to tune for cruise efficiency, you might log your fuel trims at a constant cruising speed or constant throttle position, then change one parameter, then make a second log at the same speed or TPS value. That way you can see the effect that your change made.
It's slow, painstaking work.
What most guys do is focus on one aspect of their tuning at a time. For example, if you are trying to tune for cruise efficiency, you might log your fuel trims at a constant cruising speed or constant throttle position, then change one parameter, then make a second log at the same speed or TPS value. That way you can see the effect that your change made.
It's slow, painstaking work.
yeah, i guess you'd need to carry around a nice large 'disk array' then run some queries on the data. limited disk space can be a problem.
sounds like you agree that single shot tune won't result in the best performance.
Drifting
Joined: Jul 2003
Posts: 1,796
Likes: 1
From: Annandale VA
Originally Posted by Zig
sounds like you agree that single shot tune won't result in the best performance.
Chuck of CoW doesn't like dyno tunes, and prefers to use his library of previously successful tunes, tweaked by data logging done on the street. The problem there is that the OEM O2 sensors aren't that accurate, and it's hard to find a street where you can drive 115 MPH, especially during the daylight in suburban NY. His tune does result in excellent street manners, throttle response, and SOTP performance. Track performance is still unknown, but I do have some evidence that I'm running a little lean at WOT.
Safety Car
Joined: Dec 2004
Posts: 3,565
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From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
Originally Posted by HITMAN99
I have never had a single shot tune, so I wouldn't know. In my opinion, the optimal tune would be a speed density tune (no MAF), followed by several dyno pulls, then backed up with some track and/or street testing using a wideband O2 sensor. However, this requires welding an additional O2 bung into your exhaust system, and most guys aren't up for that.
Chuck of CoW doesn't like dyno tunes, and prefers to use his library of previously successful tunes, tweaked by data logging done on the street. The problem there is that the OEM O2 sensors aren't that accurate, and it's hard to find a street where you can drive 115 MPH, especially during the daylight in suburban NY. His tune does result in excellent street manners, throttle response, and SOTP performance. Track performance is still unknown, but I do have some evidence that I'm running a little lean at WOT.
Chuck of CoW doesn't like dyno tunes, and prefers to use his library of previously successful tunes, tweaked by data logging done on the street. The problem there is that the OEM O2 sensors aren't that accurate, and it's hard to find a street where you can drive 115 MPH, especially during the daylight in suburban NY. His tune does result in excellent street manners, throttle response, and SOTP performance. Track performance is still unknown, but I do have some evidence that I'm running a little lean at WOT.
did you do the term. ? what makes you say lean at wot ? got ping ?
Drifting
Joined: Jul 2003
Posts: 1,796
Likes: 1
From: Annandale VA
Not sure what "term" is.
I had a similar experience to Yell03, went to the track and got crummy numbers. A quick trip to my local dyno showed A/F around 13:1, lots of KR. I suspect that my O2 sensors are just not that accurate (compared to the wideband tailpipe sniffer used on the dyno), so I will have to do some tweaking.
I had a similar experience to Yell03, went to the track and got crummy numbers. A quick trip to my local dyno showed A/F around 13:1, lots of KR. I suspect that my O2 sensors are just not that accurate (compared to the wideband tailpipe sniffer used on the dyno), so I will have to do some tweaking.
Safety Car
Joined: Dec 2004
Posts: 3,565
Likes: 5
From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
Originally Posted by HITMAN99
Not sure what "term" is.
I had a similar experience to Yell03, went to the track and got crummy numbers. A quick trip to my local dyno showed A/F around 13:1, lots of KR. I suspect that my O2 sensors are just not that accurate (compared to the wideband tailpipe sniffer used on the dyno), so I will have to do some tweaking.
I had a similar experience to Yell03, went to the track and got crummy numbers. A quick trip to my local dyno showed A/F around 13:1, lots of KR. I suspect that my O2 sensors are just not that accurate (compared to the wideband tailpipe sniffer used on the dyno), so I will have to do some tweaking.
i know, you don't agree with me but have you tried a one step cooler spark plug ?
Pro
Joined: Feb 2006
Posts: 632
Likes: 0
From: KINGS PARK NY
Originally Posted by yell03
I am going back tomorrow to get my Tune adjusted.
The stock tune would run good, but a custom tune can:
1 - Clear any codes that might pop up due to the headers
2 - Delete skipshift on manual trannies
3 - Turn your fans on earlier for your 160 stat
4 - Raise your rev limiter a bit
5 - Reduce Torque Management
Howard
The stock tune would run good, but a custom tune can:
1 - Clear any codes that might pop up due to the headers
2 - Delete skipshift on manual trannies
3 - Turn your fans on earlier for your 160 stat
4 - Raise your rev limiter a bit
5 - Reduce Torque Management
Howard
Drifting
Joined: Jul 2003
Posts: 1,796
Likes: 1
From: Annandale VA
Originally Posted by Zig
ooppss.. meant to say therm. you also did the 160 therm didn't you ? if you're getting preignition on the top end, it would seem that a lower temp therm. doesn't do much to prevent it, but then again it depends on the tune so i really can't say the lower temp therm didn't help.
i know, you don't agree with me but have you tried a one step cooler spark plug ?
i know, you don't agree with me but have you tried a one step cooler spark plug ?
Safety Car
Joined: Dec 2004
Posts: 3,565
Likes: 5
From: stafford country, va. Avatar: Me on turn 3 @ Bristol (The World's Fastest Half-Mile)
Originally Posted by HITMAN99
...a colder plug.
Originally Posted by HITMAN99
I ran NGK TR6 plugs (vs the standard TR55's) in my previous car because of the milled heads, higher compression.
Last edited by Zig; Nov 7, 2006 at 11:53 AM. Reason: ooppss... typo. hols off not of ....der..
Drifting
Joined: Jul 2003
Posts: 1,796
Likes: 1
From: Annandale VA
Because it may not stay clean, it could foul at lower RPMs. Colder plugs are more prone to fouling. With today's higher voltage ignition systems, that is less of an issue, but it is still an issue.
Because of the fouling, the colder plugs may not continue to fire correctly.
Because colder plugs will not do much at all to reduce preignition caused by an incorrect A/F mix.
Because there is no benefit to running a colder plug, but possible problems.
Because it is not the correct heat range plug for my motor.
Because, EVEN IF it might help alleviate the symptoms of my immediate problem, as soon as I get the A/F mix adjusted correctly, I would just have to switch the plugs back.
Trying to cure an A/F mix problem by changing plugs is like trying to cure a fever by immersing yourself in cold water. The result is pneumonia (read James Michener's "Hawaii" for that little nugget of info).
Because of the fouling, the colder plugs may not continue to fire correctly.
Because colder plugs will not do much at all to reduce preignition caused by an incorrect A/F mix.
Because there is no benefit to running a colder plug, but possible problems.
Because it is not the correct heat range plug for my motor.
Because, EVEN IF it might help alleviate the symptoms of my immediate problem, as soon as I get the A/F mix adjusted correctly, I would just have to switch the plugs back.
Trying to cure an A/F mix problem by changing plugs is like trying to cure a fever by immersing yourself in cold water. The result is pneumonia (read James Michener's "Hawaii" for that little nugget of info).
Former Vendor
Joined: Nov 2005
Posts: 11,792
Likes: 255
From: Ossining New York
St. Jude Donor '07-'08-'09-'10-'12-'13-'14
Keep This In Mind.....
Originally Posted by HITMAN99
Not sure what "term" is.
I had a similar experience to Yell03, went to the track and got crummy numbers. A quick trip to my local dyno showed A/F around 13:1, lots of KR. I suspect that my O2 sensors are just not that accurate (compared to the wideband tailpipe sniffer used on the dyno), so I will have to do some tweaking.
I had a similar experience to Yell03, went to the track and got crummy numbers. A quick trip to my local dyno showed A/F around 13:1, lots of KR. I suspect that my O2 sensors are just not that accurate (compared to the wideband tailpipe sniffer used on the dyno), so I will have to do some tweaking.
Sure it's good to check with a wideband.....but, don't bother with the wideband on the dyno.....WELD a bung into your car....BEFORE THE CAT....and get a "REAL" reading on the street....REMEMBER LOAD is different from the dyno to the street and IGN TIMING is different depending on load.....PLUS with a forced cold air system the car will run too rich on the dyno......
Wanna be real smart....Buy the LC-1 Wideband controller and a guage...Install it in the car....THEN tell me what the AFR is on the street......This is the ONLY way to do it right. EVERYONE should have one......
Call me if you have any questions.......
Chuck CoW
Team Owner
Joined: Jan 2004
Posts: 38,772
Likes: 621
From: Boston MA
St. Jude Donor '06-'07-'08,'12-'13
Originally Posted by Chuck CoW
Keep this in mind....ESPECIALLY WITH AN AUTOMATIC.....The reason I don't use a dyno is because ENGINE LOAD is different from the DYNO to the STREET.......
Sure it's good to check with a wideband.....but, don't bother with the wideband on the dyno.....WELD a bung into your car....BEFORE THE CAT....and get a "REAL" reading on the street....REMEMBER LOAD is different from the dyno to the street and IGN TIMING is different depending on load.....PLUS with a forced cold air system the car will run too rich on the dyno......
Wanna be real smart....Buy the LC-1 Wideband controller and a guage...Install it in the car....THEN tell me what the AFR is on the street......This is the ONLY way to do it right. EVERYONE should have one......
Call me if you have any questions.......
Chuck CoW
Sure it's good to check with a wideband.....but, don't bother with the wideband on the dyno.....WELD a bung into your car....BEFORE THE CAT....and get a "REAL" reading on the street....REMEMBER LOAD is different from the dyno to the street and IGN TIMING is different depending on load.....PLUS with a forced cold air system the car will run too rich on the dyno......
Wanna be real smart....Buy the LC-1 Wideband controller and a guage...Install it in the car....THEN tell me what the AFR is on the street......This is the ONLY way to do it right. EVERYONE should have one......
Call me if you have any questions.......
Chuck CoW
I bought the EASE SOftware setup so i can pull real time STREET data for my tune ~