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Discussion Starter · #1 ·
Last week I ran 11.97 @ 116.21. During the past week I put my car on the dyno and got the AFR dialed in , it picked up 12 rwhp and 8 rwtq. Since the weather was good , I figured I would make one last trip to the track this year. These are the numbers from the best run:

60' - 1.772
330' - 5.026
660' - 7.657 @ 95.31
1000'- 9.924
1320'- 11.847 @ 118.82 :D

Before this the car was very consistent.

12.015 @ 119.01
11.974 @ 118.76
12.024 @ 119.40
11.988 @ 119.14

There is something that I can't figure out though ; When the car runs a good ET it seems to lose some MPH , but it loses it between the 1/8th mile and the finishline. For example , last week it ran 12.06 @ 118.13 and was doing 92.73 at the 1/8th. Even though I picked up just over two tenths , it looks like I lost about 2.5 MPH in the last half of the track. Aside from that , I think that these are awesome numbers for a car on the stock tires and running through the completely stock exhaust.
 

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Those are awsome #'s.

The trap speeds could be due to gearing. When you ET the car better its getting to the finishline quicker, in which the car has less time to build MPH. Another theory is the car may be running out of gear towards the finishline on the good quicker ET runs, since you are getting there quicker.

I notice the same thing for my runs. My best ET is a [email protected], my best mph was today [email protected] But I run a consistent 114mph.
 

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Great Times

Butcher, You have a strong running car and that is a great series you ran this weekend. Congratulations. Cold air rules.

Please say a little more about the MAFT you are using.

As to the decreasing trap question, I find it useful to load my runs in an Excel spread sheet which calculates ALL the incremental times of each run. It helps me see the effect shifting and weather have.

Ranger
 

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WOW!! :eek: Those times are killer!! Great 60' times!! What is your launch technique??

Be sure to enter your timeslips into our Performance Data Center. :cool:
 

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Discussion Starter · #6 ·
Ranger - I'm not sure what you want to know , but it's the Ramchargers MAF Translator. I spliced the wires to install it because the people at Ramchargers told me that they weren't sure when they would have the new harness available. Keep in mind that it is only a new harness they are making , it's still the same Translator.

EBZ06 - To get the AFR dialed in , you simply put your car on a chassis dyno with a wide band O2 sensor. Most people who have a dyno also have the sensor. The first thing you want to do is get your LTFT's to 0. This is taken care of by the 30# injectors. Put at least 100 miles of normal driving on the car (after installing the injectors) and then check your LTFT's. However , with the LTFT's at 0 and with 30# injectors , the car will run very rich at WOT. This is where the dyno comes in. You want your AFR to be in the high 12's to low 13's range (no higher than 13.1). By adjusting the WOT setting on the MAFT you can change your AFR at WOT. In theory , the PCM doesn't sample the O2 sensors at WOT , so this should not change over time. The best part is that not only will you make more power , but also make a huge improvement in you MPG. I picked up over 2 MPG after getting it dialed in. I use to average 18.8 to 19.3 MPG and now I'm getting over 21 MPG and I'm making 12 more rwhp to boot. I run the Accel injectors. They are basically the same as the SVO injectors except that they are flow tested , matched in sets and they only cost $240-$250 from JEGS or Summit. In case you were wondering , my MAFT settings are:

Base - 0
WOT - -10%

fcalmes - The launch technique? Well , first and foremost , you HAVE to do a burn out. I back into the front edge of the water so that it's easy to break the tires loose. Pop the clutch at about 3000 rpms and then step on the brake with my left foot. Right after the tires start to smoke I release the brake and spin the tires up to the starting line. Throughout the whole process I never exceed half throttle or 5000 rpms. I also run the rear tires at 26 psi at the track. Then I roll the car into the pre-stage beam , at which point I stop and put the car in neutral. Then I put my left foot on the clutch pedal , exactly where I want it to be , and put the trans in 1st gear. I ease up on the clutch until the stage light barely comes on and then push the pedal back down. Not to the floor , but to just past the point of friction. Then I bring the motor up to about 3300-3500 and wait for the green. I don't focus on reaction times when I'm not actually racing. When the last yellow starts to go out I let the clutch out and put the gas pedal to the floor. It's pretty much one fluid motion , and it has to be smooth but quick. By 60' the clutch is out and the gas is floored. This is something you have to get a feel for. Every car and every track is going to be a little different. And , in case anybody was wondering , I don't powershift.

As for posting my time slips , I'm a car guy , not a computer guy. I don't have a scanner and don't have the slightest idea as to how to post a picture.:-? I can fax my slips if someone else wants to post them , but that's about it. I faxed my time slips from last weekend to Jim Hall , but I haven't heard from him since.
 

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Discussion Starter · #7 ·
By the way , congratulations on your time Ranger. Nice run. It would have been nice to see what would have happened on the run with the 1.70 60'.:)
 

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butcher said:
....Ranger....It would have been nice to see what would have happened on the run with the 1.70 60'.:)
Butcher,

Sure woulda. It was THE last run of the year, right after my 11.95. I launched at 3900 after my best burn-out (still learning and without a line-lock). The car hooked so strongly that it startled me; I just hung on and slammed the limiter so hard the nose fell all the way down. :(

The good part is I know what to expect next time. I've got 16 runs on the DR and they DO take some getting used to.

Ranger
 

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butcher said:
Ranger - I'm not sure what you want to know , but it's the Ramchargers MAF Translator. I spliced the wires to install it because the people at Ramchargers told me that they weren't sure when they would have the new harness available. Keep in mind that it is only a new harness they are making , it's still the same Translator.

EBZ06 - To get the AFR dialed in , you simply put your car on a chassis dyno with a wide band O2 sensor. Most people who have a dyno also have the sensor. The first thing you want to do is get your LTFT's to 0. This is taken care of by the 30# injectors. Put at least 100 miles of normal driving on the car (after installing the injectors) and then check your LTFT's. However , with the LTFT's at 0 and with 30# injectors , the car will run very rich at WOT. This is where the dyno comes in. You want your AFR to be in the high 12's to low 13's range (no higher than 13.1). By adjusting the WOT setting on the MAFT you can change your AFR at WOT. In theory , the PCM doesn't sample the O2 sensors at WOT , so this should not change over time. The best part is that not only will you make more power , but also make a huge improvement in you MPG. I picked up over 2 MPG after getting it dialed in. I use to average 18.8 to 19.3 MPG and now I'm getting over 21 MPG and I'm making 12 more rwhp to boot. I run the Accel injectors. They are basically the same as the SVO injectors except that they are flow tested , matched in sets and they only cost $240-$250 from JEGS or Summit. In case you were wondering , my MAFT settings are:

Base - 0
WOT - -10%

fcalmes - The launch technique? Well , first and foremost , you HAVE to do a burn out. I back into the front edge of the water so that it's easy to break the tires loose. Pop the clutch at about 3000 rpms and then step on the brake with my left foot. Right after the tires start to smoke I release the brake and spin the tires up to the starting line. Throughout the whole process I never exceed half throttle or 5000 rpms. I also run the rear tires at 26 psi at the track. Then I roll the car into the pre-stage beam , at which point I stop and put the car in neutral. Then I put my left foot on the clutch pedal , exactly where I want it to be , and put the trans in 1st gear. I ease up on the clutch until the stage light barely comes on and then push the pedal back down. Not to the floor , but to just past the point of friction. Then I bring the motor up to about 3300-3500 and wait for the green. I don't focus on reaction times when I'm not actually racing. When the last yellow starts to go out I let the clutch out and put the gas pedal to the floor. It's pretty much one fluid motion , and it has to be smooth but quick. By 60' the clutch is out and the gas is floored. This is something you have to get a feel for. Every car and every track is going to be a little different. And , in case anybody was wondering , I don't powershift.

As for posting my time slips , I'm a car guy , not a computer guy. I don't have a scanner and don't have the slightest idea as to how to post a picture.:-? I can fax my slips if someone else wants to post them , but that's about it. I faxed my time slips from last weekend to Jim Hall , but I haven't heard from him since.
Butcher, Congrats on the times and proveing the value of the 02 upgrades!! I thought the cam and valve train upgrades would be good for power and you figured out how to take advantage. Now next year with more run's....and power shifting 11.4?? Your discriptive launch technique looks and reads very well. WELL DONE, Congrats again. Ric
 

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Butcher...

Does your car have headers or just the mods you state down there?

Thanks
 

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Nice times and mph..:cheers:
 

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Discussion Starter · #12 ·
PowerShifter - Thanks. I have been drag racing for 17 years now , so I don't think I'll get too much better with more track time. This was my fifth time at the track with this car , I probably have close to 30 passes already. The first two times at the track were horrible. I either bogged it or got real bad wheel hop. Then , on the third trip to the track , I tried doing a burn out. Viola! It worked , but I was at a terrible track. The track that I ran these times at is good , but by no means is it the best in the area. I'm lucky , I have 4 (that's right , 4) drag strips within an hour and a half of my house. :D The one I was at is 3rd on the list in terms of track prep and traction. It has a little more left in it , I could see a 1.72 or a 1.71 60' with the stock tires an a good track. If I don't touch the car , I might be able to get a low 11.7 out of it. Powershifting won't make the car any quicker or faster. Keep in mind , I'm moving the shifter and clutch at the same speed , I'm just lifting off the gas in the process. Believe me , I've tried.

Highlander - Just the mods in the sig. Stock thermostat , stock throttle body , stock spark plugs , stock tires , and the completely stock exhaust. I have to give credit where credit is due. The Halltech is a great piece ; The Halltech and MAFT are an AWESOME combination. I have to think that they are good for a minimum , a minimum , of 25 rwhp and 30 rwtq. That's impressive for $700 worth of parts that you can bolt on in a couple of minutes in your garage. And on a car that is supposed to be pretty much "maxed out" from the factory. I say $700 because I believe that you could get the exact same results with the factory injectors , you would just have to spend some more time getting it dialed in though.
 

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normjack said:

When you ET the car better its getting to the finishline quicker, in which the car has less time to build MPH.
I think this is what is happening. Suggest you calc 'hook factor'. That is ET x MPH. If you look at record holders, reguardless or class, the hook is usually around 1320 or slightly lower. Track your hook factor for every run. You will see the trend.
 

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I ahve the same car with the same mods except for a Blackwing instead of T-1.

How did you get your LTFT. I use a scanner, I didn't think a dyno could tell you those #'s. Right now I ahve my base set to 5% lean. WOT 0% I have not played with that yet. There might be more gains there with the LTFT and the MAFT. I have 0 knocks and timing at about 28 deg. WOT, there is a little room for improvement. Waiting for MAFT adjustment to kick in, as it is not instant with Base. I will try your 10% lean and dyno.

GREAT NUMBERS!!! :cheers:
MAFT RULE!;)
 

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Re: Great Times

Ranger said:
I find it useful to load my runs in an Excel spread sheet which calculates ALL the incremental times of each run. It helps me see the effect shifting and weather have.
I agree with the spreadsheet system and incremental times. I also add tire pressure, launch rpm, temp, baro pressure, humidity, AD%, HP correction factor, hook factor, and Std Day corrections for all times/speeds. You could also record MAFT settings, etc. Then I sit down to sort, think, study, and analyse the data. All this gives me new ideas for what to try next.

About launch techniques, you guys are validating what I posted earlier about the Quarter Jr model showing continued ET improvements with higher launch rpm up to 5000 to the 60' mark.
 

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Discussion Starter · #16 ·
02Z06 - If you have 30# injectors , set your base to 0. I originally thought that I should lean out the base a little bit because the injectors were so much bigger , but this defeats the purpose of the 30#r's. I think that the PCM sets the LTFT's by the O2 sensors only. So when you lean it out , the PCM pulls fuel out but then the O2's read a lean condition and inject more fuel. The MAFT works the opposite way you would think that it does. If you get a positive number on your scanner , then you need to richen the mixture on the MAFT and if you get a negative number , lean it out. Set it to 0 , put about 100 miles of normal driving on it (whatever that may be :D ) and check it again.

The dyno is only used to adjust WOT settings , since you spend most of the time at WOT on the dyno , this is perfect. :D You want your LTFT's at 0 because this gives you the perfect starting point. If you can watch your AFR on the dyno , you'll notice that it is always in the mid 14's at part throttle. No matter what you have your MAFT set to , it will always read mid 14's (if possible). That's what the PCM is programmed to do in closed loop (part throttle), achieve a 14.7:1 AFR. When it can't , or when it has to make too many changes to get that ratio is when the "Check Engine" light comes on. When you go to open loop (WOT) the PCM ignores the O2 sensors and goes to the fuel and timing tables that it learns at part throttle. The PCM still reads the MAF at WOT which is why the Translator works. However , with your LTFT's at 0 , it will still run extremely rich at WOT. Once you get your LTFT's to 0 , then put it on the dyno with a wide band O2 sensor. The factory O2's have e reputation for being very inaccurate , so don't rely on them alone. With your LTFT's at 0 and your MAFT set to 0 WOT , your AFR will probably go off the scale for part of your first pull (meaning below 10.0 AFR). Keep leaning it out at WOT until your AFR gets to the high 12 to low 13 range , or until power falls off. Also , try to keep your pulls consistent. Meaning , keep your coolant temps below 200 degrees at the start of each pull , make each pull from the same RPM to the same RPM , etc. etc. Since the PCM doesn't "read" the O2 sensors at WOT , and since you don't spend most of the time driving your car at WOT , these settings shouldn't really change over time. Unless , of course , you make changes to your motor. At least that's been my experience. I hope this answers your question. Now , go get that thing dialed in! :lol: :D
 

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butcher,

Great thread. Awesome times.

There is a lot of info on this site......

Thanks

:D :D
 

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Great Info - Thanks

Butcher and Ranger,

Keep the info coming! I am learning more and more from reading your posts.

Question - I have an 01, since the '01 had slightly bigger injectors than the '02 model, do you guys think I still should move up to #30 injectors?

The only mod so far I have put on the car is the Halltech T-1 Sidewinder. Also, What do you guys think about cutting a hole in the shroud under the filter? Do you think that will bring any more cooler air to the filter when driving?
 

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What is the RWHP and RWT of you car now???:guiness:
 

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hey butcher...thanks for all the info.....helped alot...i have same mods +x-pipe and u-d pully i set the maft at 0 base and -10% at wot--- wow ....before maft 377 rwhp after 392.7 rwhp...i cant wait to hit the track sat......
 
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