Why does my bone-stock '02 automatic Z28 dyno only 280.9 rwhp @ 295.7 ft-lb.?!
#1
Update: My bone-stock 280.9 rwhp '02 A4 Z28 dynos 294.51 rwhp locked!
FOR THOSE WHO ARE TOO LAZY TO READ MY REPLIES TO MY ORIGINAL POST
Updated 12/4/04:
I drove 2 hours up to get to TT Performance where I got my factory plugs (at around 46,300 miles) replaced with brand-new NGK-TR55's. (The factory plugs were labeled DENSO, for your information and they didn't look bad at all, IMO) Taylor Thunderbolts were not in stock so I just had them use my factory plug wires. After the spark plug installation, the car was placed on the dyno jet. The agreement was that the car will be dynoed with air/fuel ratio monitoring. KR and timing will also be checked. The operator was Matt Sorian. 3 pulls were done with the first two pulls done back to back and the last pull made after a 5 minute cool down. Here were the results.
1st pull: Max Power = 291.49 Max Torque = 313.94
2nd pull: Max Power = 288.28 Max Torque = 311.89
3rd pull: Max Power = 294.51 Max Torque = 314.05
Did my brand new spark plugs get me an increase of 9 rwhp and 12 ft-lb of torque? If I was a ricer, then I'd say yeah. But no, the dyno was properly made (for A4's) where EFILive was used to lock the converter at 3rd gear WOT to accurately show how much power the engine was actually making without accounting for stall. The air/fuel ratio was rich (at around 12.0-12.1). There was no KR detected and timing (I forgot the number that Matt said) was at the normal factory setting. So, now I am happy to know that there is nothing wrong with the car and that the best way to improve my baseline quarter mile times is to not run on a full tank of gas and to somehow go from 2.1-2.2 to 1.9-2.0 60 foot times. Thanks to Matt and the other guys at TT Performance. I'm getting all of my modifications and future dynos and dyno tuning done over there.
Updated 12/20/04:
I never updated this post with my new best quarter mile time and MPH. With the recently installed and brand-new NGK-TR55 spark plugs, running with only a quarter tank of gas, and 30-31 PSI air pressure on the stock 47,000 mile GSC's, here were my results:
best time was
13.407@103.98 with a 2.075 60 foot time
and best MPH was
13.585@104.82 with a 2.257 60 foot time.
At best, I think the car is capable of getting 13.2-13.3 @ 105-106 MPH completely bone-stock (meaning no performance modifications whatsoever). I do have a rear-end girdle and a tranny cooler.
Original Post (from 11/26/04):
Updated 12/4/04:
I drove 2 hours up to get to TT Performance where I got my factory plugs (at around 46,300 miles) replaced with brand-new NGK-TR55's. (The factory plugs were labeled DENSO, for your information and they didn't look bad at all, IMO) Taylor Thunderbolts were not in stock so I just had them use my factory plug wires. After the spark plug installation, the car was placed on the dyno jet. The agreement was that the car will be dynoed with air/fuel ratio monitoring. KR and timing will also be checked. The operator was Matt Sorian. 3 pulls were done with the first two pulls done back to back and the last pull made after a 5 minute cool down. Here were the results.
1st pull: Max Power = 291.49 Max Torque = 313.94
2nd pull: Max Power = 288.28 Max Torque = 311.89
3rd pull: Max Power = 294.51 Max Torque = 314.05
Did my brand new spark plugs get me an increase of 9 rwhp and 12 ft-lb of torque? If I was a ricer, then I'd say yeah. But no, the dyno was properly made (for A4's) where EFILive was used to lock the converter at 3rd gear WOT to accurately show how much power the engine was actually making without accounting for stall. The air/fuel ratio was rich (at around 12.0-12.1). There was no KR detected and timing (I forgot the number that Matt said) was at the normal factory setting. So, now I am happy to know that there is nothing wrong with the car and that the best way to improve my baseline quarter mile times is to not run on a full tank of gas and to somehow go from 2.1-2.2 to 1.9-2.0 60 foot times. Thanks to Matt and the other guys at TT Performance. I'm getting all of my modifications and future dynos and dyno tuning done over there.
Updated 12/20/04:
I never updated this post with my new best quarter mile time and MPH. With the recently installed and brand-new NGK-TR55 spark plugs, running with only a quarter tank of gas, and 30-31 PSI air pressure on the stock 47,000 mile GSC's, here were my results:
best time was
13.407@103.98 with a 2.075 60 foot time
and best MPH was
13.585@104.82 with a 2.257 60 foot time.
At best, I think the car is capable of getting 13.2-13.3 @ 105-106 MPH completely bone-stock (meaning no performance modifications whatsoever). I do have a rear-end girdle and a tranny cooler.
Original Post (from 11/26/04):
My baseline dyno happened a while ago and the 2002 Z28 only had around 13,000 miles on the odometer. Check out the dyno graph below:
At around 46,072 miles and still completely bone-stock, I brought the car to Atco for a baseline quarter mile run. Here were the variables:
- The car had a full tank of gas.
- Each tire had 30-31 psi air pressure.
- Elevation was at -158 ft.
- Temperature was 54 degrees F.
- Relative Humidity was between 76-78%.
- Dew Point was 46.7 degrees F.
- The barometer was 30.09 inHg.
First run was 13.567@103.62; 2.095 60'
2nd 13.512@103.39; 2.107
3rd 13.804@101.84; 2.171
4th 13.687@101.92; 2.126
5th 13.540@101.80; 2.079
6th 13.679@101.84; 2.102
Is my car retarded or something? Why are my dyno numbers so low and why are my quarter mile numbers so horrible? Should I get a dyno tune? At less than 8,000 miles, the dealership replaced my transmission's pressure control solenoid, because I was getting a P0748 code. (The car was intermittently shifting too hard.) The car shifted fine afterwards. Could replacing the solenoid be related to my low power and slow times? Thanks in advance for the info.
At around 46,072 miles and still completely bone-stock, I brought the car to Atco for a baseline quarter mile run. Here were the variables:
- The car had a full tank of gas.
- Each tire had 30-31 psi air pressure.
- Elevation was at -158 ft.
- Temperature was 54 degrees F.
- Relative Humidity was between 76-78%.
- Dew Point was 46.7 degrees F.
- The barometer was 30.09 inHg.
First run was 13.567@103.62; 2.095 60'
2nd 13.512@103.39; 2.107
3rd 13.804@101.84; 2.171
4th 13.687@101.92; 2.126
5th 13.540@101.80; 2.079
6th 13.679@101.84; 2.102
Is my car retarded or something? Why are my dyno numbers so low and why are my quarter mile numbers so horrible? Should I get a dyno tune? At less than 8,000 miles, the dealership replaced my transmission's pressure control solenoid, because I was getting a P0748 code. (The car was intermittently shifting too hard.) The car shifted fine afterwards. Could replacing the solenoid be related to my low power and slow times? Thanks in advance for the info.
Last edited by damon_Z; 08-06-2005 at 06:23 AM. Reason: Because of stupid people who can't read through the replies.
#2
your power is right on line for a stock a4.
your 60's are whats killing your et's (a4's should 60' much better then 2.1)
your tire pressure is too high for the track(20-22 for street tires)
gas weights 6 lbs per gallon your tank holds 16.5 gallons thats 99 lbs ! (thats about a tenth in the 1/4 mile)
your 60's are whats killing your et's (a4's should 60' much better then 2.1)
your tire pressure is too high for the track(20-22 for street tires)
gas weights 6 lbs per gallon your tank holds 16.5 gallons thats 99 lbs ! (thats about a tenth in the 1/4 mile)
#3
I forgot to mention that it had rained the previous day and that the dragstrip had to go through a drying process. There were puddles of water after the end of the strip that was impossible to avoid. I'm thinking that those puddles could have made traction a little less than optimal? I'm gonna stick with the street air pressure and run the car with a full tank of gas. This way, I stay consistent. Here's an update:
Just recently, I had the local dealership (where I bought the car from) replace my fuel filter, clean my injectors, and drain and fill my transmission with a new ATF. Now, I just got back from a 4 hour roundtrip drive from Performance Specialties in Pottstown, PA, for 3 dyno runs on a dynojet with air fuel ratio monitoring. The weather this time around was cool with low humidity (unlike the first dyno that took place in a hot and humid day). Note that the first dyno took place at Cartek and the car back then had around 13,000 miles. Now, the car has a little over 46,000 miles. Here were the results:
Max Power = 285.1
Max Torque = 302.0
Air Fuel Ratio was 11.9.
The car seems to have gained 4 hp and 5 ft-lb. of torque just through mileage alone. Ray, at Performance Specialties, mentioned that the car was running fat and could gain 15 horsepower through dyno-tuning. Could my air fuel ratio be the reason why my car is dynoing lower than other stock f-bodies? Regarding my times in my original post, I forgot to mention that 5 of the 6 passes were done when the transmission was engaged in overdrive. Does that make a difference? Also, is there a chance that my spark plugs are misfiring and, therefore, I have to get them replaced? Thanks in advance for the info.
Just recently, I had the local dealership (where I bought the car from) replace my fuel filter, clean my injectors, and drain and fill my transmission with a new ATF. Now, I just got back from a 4 hour roundtrip drive from Performance Specialties in Pottstown, PA, for 3 dyno runs on a dynojet with air fuel ratio monitoring. The weather this time around was cool with low humidity (unlike the first dyno that took place in a hot and humid day). Note that the first dyno took place at Cartek and the car back then had around 13,000 miles. Now, the car has a little over 46,000 miles. Here were the results:
Max Power = 285.1
Max Torque = 302.0
Air Fuel Ratio was 11.9.
The car seems to have gained 4 hp and 5 ft-lb. of torque just through mileage alone. Ray, at Performance Specialties, mentioned that the car was running fat and could gain 15 horsepower through dyno-tuning. Could my air fuel ratio be the reason why my car is dynoing lower than other stock f-bodies? Regarding my times in my original post, I forgot to mention that 5 of the 6 passes were done when the transmission was engaged in overdrive. Does that make a difference? Also, is there a chance that my spark plugs are misfiring and, therefore, I have to get them replaced? Thanks in advance for the info.
Last edited by damon_Z; 11-27-2004 at 01:43 PM.
#5
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It looks decent but, that mph is kinda low IMO for those conditions. I'd expect 105-106mph or so. Have you ever scanned your car to see if there is any knock retard? I know when I'd get knock the car would lose a few mph on the top end. The humidity and full tank of gas didn't help either.
Other than that you are right in line for a stock car. Not to many stock A4 cars drop below 2.0 60's from what I've seen but, some do.
Other than that you are right in line for a stock car. Not to many stock A4 cars drop below 2.0 60's from what I've seen but, some do.
#6
Originally Posted by XLR8NSS
It looks decent but, that mph is kinda low IMO for those conditions. I'd expect 105-106mph or so. Have you ever scanned your car to see if there is any knock retard? I know when I'd get knock the car would lose a few mph on the top end. The humidity and full tank of gas didn't help either.
Other than that you are right in line for a stock car. Not to many stock A4 cars drop below 2.0 60's from what I've seen but, some do.
Other than that you are right in line for a stock car. Not to many stock A4 cars drop below 2.0 60's from what I've seen but, some do.
#7
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A hot engine can cause knock retard, an exhaust or any rattle can cause knock retard, it can happen on a bone stock engine, a rich engine, etc. Sometimes the sensors can be overly sensitive and cause false knock retard.
I always noticed that when my engine temp would get over 194-6 degrees on a scanner that I'd pick up a little knock retard.
I'm not saying that is what is going on with your car just something to look for.
The only way to check for it is to get a scanner like: EFILive, Autotap, HPTuners, or a Scanmaster. They all offer a scanner in some form or another that can check for knock.
I always noticed that when my engine temp would get over 194-6 degrees on a scanner that I'd pick up a little knock retard.
I'm not saying that is what is going on with your car just something to look for.
The only way to check for it is to get a scanner like: EFILive, Autotap, HPTuners, or a Scanmaster. They all offer a scanner in some form or another that can check for knock.
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#9
Yes, there is definitely some power to be gained by leaning your car out...11.9 is definitely rich for a bone stock LS1...If you get it in the 12.9-13.1 range you'd probably pick up anywhere from 5-10rwhp from you leaning the AFR out, but don't expect anymore...
I agree that your 60 times are hurting your ET's, but the MPH definitely seems low (especially those runs in the 101 area after it trapped over 103 the first two). But for what it's worth, don't get too caught up on dyno #'s. I personally would start out by putting a lid and cat-back/cutout on it and watch the thing pick up a solid 2-3 tenths and 2-3 MPH alone. Some good headers and a 3000+ stall on DR's will have that car in the mid to even low 12's before you know it. Don't forget to have the plugs/wires changed out too before long.
Good luck,
Mike
I agree that your 60 times are hurting your ET's, but the MPH definitely seems low (especially those runs in the 101 area after it trapped over 103 the first two). But for what it's worth, don't get too caught up on dyno #'s. I personally would start out by putting a lid and cat-back/cutout on it and watch the thing pick up a solid 2-3 tenths and 2-3 MPH alone. Some good headers and a 3000+ stall on DR's will have that car in the mid to even low 12's before you know it. Don't forget to have the plugs/wires changed out too before long.
Good luck,
Mike
#10
Originally Posted by 2000LS1Z28
Yes, there is definitely some power to be gained by leaning your car out...11.9 is definitely rich for a bone stock LS1...If you get it in the 12.9-13.1 range you'd probably pick up anywhere from 5-10rwhp from you leaning the AFR out, but don't expect anymore...
I agree that your 60 times are hurting your ET's, but the MPH definitely seems low (especially those runs in the 101 area after it trapped over 103 the first two). But for what it's worth, don't get too caught up on dyno #'s. I personally would start out by putting a lid and cat-back/cutout on it and watch the thing pick up a solid 2-3 tenths and 2-3 MPH alone. Some good headers and a 3000+ stall on DR's will have that car in the mid to even low 12's before you know it. Don't forget to have the plugs/wires changed out too before long.
Good luck,
Mike
I agree that your 60 times are hurting your ET's, but the MPH definitely seems low (especially those runs in the 101 area after it trapped over 103 the first two). But for what it's worth, don't get too caught up on dyno #'s. I personally would start out by putting a lid and cat-back/cutout on it and watch the thing pick up a solid 2-3 tenths and 2-3 MPH alone. Some good headers and a 3000+ stall on DR's will have that car in the mid to even low 12's before you know it. Don't forget to have the plugs/wires changed out too before long.
Good luck,
Mike
#11
Originally Posted by damon_Z
Before doing any mods, I'm gonna try a few more things. I'll use a GM Top Engine Cleaner to clean my combustion chamber and switch my worn out factory Delcos or NGK spark plugs to brand new TR-55's that I got as a gift a couple years ago. I'll do all my runs with the transmission engaged in D and not overdrive. And I'll try to run at only at least half tank of gas to save a little weight. I'm not going to dyno tune the car since it's only bone-stock, but I might do a final baseline dyno after all is said and done.
Good luck!
Last edited by 2000LS1Z28; 11-28-2004 at 02:17 PM.
#12
Your numbers don't sound too bad to me.
My 00 A4 SS only put down 289.9/297.7 stock,and the best time i got at the track was 13.24@104.8 W/ 2.0 60ft all dead stock.
I would get a cut out and a air lid. then see if your times and dyno numbers go your way.
Good luck,Dave.
My 00 A4 SS only put down 289.9/297.7 stock,and the best time i got at the track was 13.24@104.8 W/ 2.0 60ft all dead stock.
I would get a cut out and a air lid. then see if your times and dyno numbers go your way.
Good luck,Dave.
#13
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Another great relatively inexspensive mod is the FTRA. It's a little better than the completely free FRA mod. That and a lid will help quite a bit. I agree with all the mods listed by the other guys too. Great list to get into the mid/low 12's.
Definately leave the shifter in OD, D won't help at all.
Definately leave the shifter in OD, D won't help at all.
#14
Originally Posted by XLR8NSS
Another great relatively inexspensive mod is the FTRA. It's a little better than the completely free FRA mod. That and a lid will help quite a bit. I agree with all the mods listed by the other guys too. Great list to get into the mid/low 12's.
Definately leave the shifter in OD, D won't help at all.
Definately leave the shifter in OD, D won't help at all.
#15
For an 02, those #'s are a little low, even for an A4. The dip in your dyno graph tells me something is wrong. Get the car Auto tapped and get a good tune. The slightest thing wrong puts these cars in limp mode and retardt the timing. Good luck. CarTech should know what they are doing and be of great help to you.
#16
Originally Posted by davered00ss
For an 02, those #'s are a little low, even for an A4. The dip in your dyno graph tells me something is wrong. Get the car Auto tapped and get a good tune. The slightest thing wrong puts these cars in limp mode and retardt the timing. Good luck. CarTech should know what they are doing and be of great help to you.
#17
I just made an appointment with TT Performance for this Saturday to dyno the car with air/fuel ratio, KR, and timing monitoring after they do a plug and wire installation. This will be my third set of baseline dynos, but this one will tell me if there really is something wrong with my car or not. I'm hoping there is something wrong with my car so that I can find out how to fix it and hopefully free up at least 25 rwhp that seems to be missing right now.
#18
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Originally Posted by damon_Z
I just made an appointment with TT Performance for this Saturday to dyno the car with air/fuel ratio, KR, and timing monitoring after they do a plug and wire installation. This will be my third set of baseline dynos, but this one will tell me if there really is something wrong with my car or not. I'm hoping there is something wrong with my car so that I can find out how to fix it and hopefully free up at least 25 rwhp that seems to be missing right now.
IF nothing is wrong a few mods will wake that sucker right up though.
#20
Originally Posted by 2000LS1Z28
Yes, there is definitely some power to be gained by leaning your car out...11.9 is definitely rich for a bone stock LS1...If you get it in the 12.9-13.1 range you'd probably pick up anywhere from 5-10rwhp from you leaning the AFR out, but don't expect anymore...
I agree that your 60 times are hurting your ET's, but the MPH definitely seems low (especially those runs in the 101 area after it trapped over 103 the first two). But for what it's worth, don't get too caught up on dyno #'s. I personally would start out by putting a lid and cat-back/cutout on it and watch the thing pick up a solid 2-3 tenths and 2-3 MPH alone. Some good headers and a 3000+ stall on DR's will have that car in the mid to even low 12's before you know it. Don't forget to have the plugs/wires changed out too before long.
Good luck,
Mike
I agree that your 60 times are hurting your ET's, but the MPH definitely seems low (especially those runs in the 101 area after it trapped over 103 the first two). But for what it's worth, don't get too caught up on dyno #'s. I personally would start out by putting a lid and cat-back/cutout on it and watch the thing pick up a solid 2-3 tenths and 2-3 MPH alone. Some good headers and a 3000+ stall on DR's will have that car in the mid to even low 12's before you know it. Don't forget to have the plugs/wires changed out too before long.
Good luck,
Mike
This is true but the numbers seem exactly on to me. I mean most of the A4s in the 300rwhp range have a lid/catback. Believe it or not those two things will made a 10-20rwhp difference alone. Might even lean it out enough for your liking also.