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  1. #1
    Junior Member nukkinfuttz's Avatar
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    14.49 ET @96mph. HELP!

    I have had this car for about 2 years. 2000 Trans Am with LS1 A4. When I got it, it had only a MagnaFlow Catback. I took it to the track and ran it for a baseline last year on sept 9th. I ran a 14.45@96mph. I thought that was pretty bad. I have removed and replaced the exhaust with a SLP Loud Mouth, installed a K&N Filter, SLP AirLid and changed all the spark plugs. I took it to the track this past Friday night and to my amaizement, it ran exactly the same time and MPH it did last year at this same time.

    This tells me something else must be holding this car back. I have been searching though this site and find that "normal" for stock LS1 car should be somewhere around 13.75'ish and 104-106MPH for an A4, so I know something must be wrong.

    I just took the car on a long road trip and found its getting 22.2mpg which seems like is normal according to other folks sharing their info here.

    What do you guys think I should be looking at? Does this sound like maybe partially plugged cats? Fuel pump that does not deliver full rate?
    I just hooked up my scanner and find no codes. I also find the long term fuel trims are about -1.5%, so they don't seem to be maxed out in either direction.

    Im looking for some hints on how to test for what could be wrong. Thanks!

  2. #2
    Member sjgreen6's Avatar
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    Navy Blue
    2002 Trans Am WS6 Conv

    Couple of questions first to get a better idea of what you are working with: How many miles does the car have? What rear gear does your car have? The 3.23 was an option on the TA, even with the WS6 with automatic trans. If you have the lower base gear it could really be holding you back. Are you spinning off the line or can you apply full throttle with little to no spin? The changes that you have made are very limited in actually increasing horsepower. More optimizing what is already there assuming everything else is in top condition. Top bolt-on things on the list to increase power for an LS1 are headers, rear gear (3.73 to 4.10 for the auto trans cars), higher stall converter in the trans, and a custom computer retune from Frost or another competent shop. After that you really need to start looking at improvements to your suspension before you start into internals like a cam, heads, induction or other power adders.

  3. #3
    Veteran pajeff02's Avatar
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    Black & Blue
    '02 WS.6 / '07 Suburban

    How did you launch the car and what was the temp and humidity when you ran it? On a hot and humid day our car will run almost 4/10ths of a second slower in the 1/4 mile.

  4. #4
    Veteran 0rion's Avatar
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    98 Formula
    06 duramax

    my first time at the track with mine was on a hot and humid day in august and I ran a 13.99 @ 99mph so there may not really be anything wrong with your car. What did your 60's look like? A tune would help you quite a bit also.
    Quote Originally Posted by Mean Green Z28 View Post
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  5. #5
    Senior Member Naaman's Avatar
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    Cayanne
    98 Z28 Vert M6

    If the car in the avatar is the same car, I'm wondering what wheels those are? I doubt it would be the sole reason, but if they are taller, and depending on the tire specs, you could have a gearing increase at the wheels (slowing you down).
    Lid, Throttle Body, LS6 Intake, Heads, Cam, Magnaflow, LS7 Clutch, SFCs, STB, Panhard Bar, Strano Springs, Hollow Sway Bars, Poly/Roto LCAs, Konis, MGW Shifter

  6. #6
    Junior Member nukkinfuttz's Avatar
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    2000 Trans Am

    The car just rolled 200k this week.
    It has what I believe to be the 3.23 rear. Also, I pulled the diff cover off and found it had a geared posi unit, not a clutch type.
    The person I bought it from put the corvette rims on it, so 18" in the back,17" in front. I then put nitto 555nt all the way around with a 45 aspect ratio. I think I see the problem now that you guys asked this series of questions.... It is a complete dawg from a dig. I cannot spin the rears on dry pavement when power braking, so I have excellent traction with the power available... But certainly sounds like a better gear is the next best corse of action.
    At the track, I can floor the gas pedal while waiting on the tree and get zero wheel spin off the line. Traction control is off. The 60' time was 2.15s
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  7. #7
    Junior Member nukkinfuttz's Avatar
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    As far as temp and humidity, not sure. I know it was a nice cool day, wasn't even breaking a sweat. I'll see if I can find those stats on the Internet for last Friday in my area. But my general thought is it was not a terrible day for racing.

  8. #8
    Veteran pajeff02's Avatar
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    Black & Blue
    '02 WS.6 / '07 Suburban

    Our A4 equipped car ran 13.43 on its first track outing in stock trim with 60' times in the 2.1 to 2.2 second range. Sounds like it is coming off the line ok.

  9. #9
    Veteran 0rion's Avatar
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    98 Formula
    06 duramax

    I see you have a K&N....when was the last time you cleaned the MAF sensor? To me it does sound like the car is down on power but I'm not sure I would say there's a problem there. Might just need a few little things done to it...primarily a tune but I would knock out a few mods before doing the tune. Throw some headers and a tune at it.

    There's also some free or low dollar mods you could do too that might help a little bit. Free ram air, tb coolant bypass, fernco hose, ect ect.

  10. #10
    Veteran Firebirdjones's Avatar
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    I wouldn't be too alarmed just yet. If the car has 2.73 gears, and with 200,000 miles, I don't see anything all that unusual. Couple in the fact that we don't know what the DA might have been. Temp, humidity, elevation all play a roll and can effect ET's up to a full second if extreme enough.

    I can tell you my 02 SS auto with 3.23's and bone stock, although it did have the optional SLP dual/dual with CME, so you could say it had a catback on it from the factory.
    It ran 13.70's at 102 and the DA was in the 3,000' range which was pretty normal for Ohio in the summer time. I could floor the throttle, no wheel spin, and 60 foot times were similar to yours.
    I put a tune in the car and nothing else, ran 13.40s at 104 mph.

    I put headers and off road Y on and ran 13.30's at 105-106.

    A 3400 stall converter got me a 12.76 at 108 mph.

    All runs made on stock rubber, the converter made things tricky with a little more finesse to get it out of the hole cleanly.

    I'd go through a solid tune up procesure, clean the MAF, new plugs etc.. which likely all should be done anyway before you go throwing performance add ons at the car. You'll probably find the car is running okay, but without more details on conditions we can only guess.
    Last edited by Firebirdjones; 09-21-2015 at 04:52 AM.

  11. #11
    Junior Member nukkinfuttz's Avatar
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    Oh, I did clean the MAF sensor two days before taking it to the track with the MAF cleaner sold at advance auto parts.
    I just did new NGK TR55 plugs in the last two weeks as well.
    The track was located in Richmond Va which is about 130' above sea level so lack of good air pressure should not be a factor. That's almost as good as it gets.

  12. #12
    Junior Member nukkinfuttz's Avatar
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    Almanac says temp at 6pm on 9/18/15 was 81* at the location of the track. Sorry cannot find humidity at that time, only a daily average of 68%

  13. #13
    Junior Member nukkinfuttz's Avatar
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    Quote Originally Posted by Firebirdjones View Post
    . If the car has 2.73 gears.
    I posted above it has 3.23 gears. We pulled the diff cover and looked at the tooth count stamped on the gears then did the math.

    Does that change your opinion at all?

  14. #14
    Junior Member nukkinfuttz's Avatar
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    Thanks to all who have shared thier times! So it looks like other A4 cars pulling 2.1-2.2 60' are running mid 13's and over 100mph, it would seem my car can get moving fine, but must be having trouble in the high RPMS.... Does that sound reasonable?

    If that is the case, what things can stall airflow or fuel flow at high RPMS? Right?
    So I think we covered the baseline checks that maintenance should be up to
    Par, airflow mods are in place... The only reasons I can think of are partially plugged cats that cannot deliver full CFM flow anymore, or a fuel pump that won't deliver max quantity. Since this is a return less system, I can't think of a way to verify total pump flow at max pressure. Any ideas?

  15. #15
    Senior Member kingls1's Avatar
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    1999 Trans-Am, 2012 Sonic

    Your rail pressure should be 58psi you can check it with a gauge right at end of rail. Look at Marshall gauge they are a nice quality one with brass internals and made in CA. Now it may not be a bad idea to clean the maf again as the oiled filter may have dirtied it again. Also as stated above changes you made aren't huge but with out tuning the PCM to work with them really is no benefit. Frost has a good mail order tune that can change fueling, air, and shift points. Also he is close to you. Last time we were at the track it was in the 80's and I was off about 4/10 all day. Also have you run any injector cleaner through it? With 200k she may be a little tired, but bottom line with out a tune your mods aren't being used effectively..
    99 Trans Am, SLP Lid, Blackwing filter, smooth bellow, Ported TB, LS6 intake, Ws6 lower ram air box, OBX LT's, Magna Flow cat back, LS7 clutch, Tick MC, Hurst Shifter, Frost Tune, UMI SFC,LAC, STB, PB, Torq Arm, Super Hawk hood, Torq Thrust II, Kee Audio.
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  16. #16
    Veteran Firebirdjones's Avatar
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    DA Calculator - Density Altitude Calculator - DragTimes.com

    If this link above works, put the name of your track in, the date, and it grabs the weather conditions for the exact date and time of day you raced and it will tell you what the DA was for that given time of day.

    I'm still not too alarmed. 81 degrees is still pretty darn warm among the racing crowd. Even at sea level with temps that high you could have DA numbers well above 3,000 that would affect the ET up to a 1/2 second.

    All those magazine times that promote these cars....yeah those are usually done at places like Atco which is right at sea level, it's typically in the winter time when temps are 40 degrees outside, tracks are usually closed at this point, and doing the math it actually gives you a negative DA number or what us racers call "mine shaft air"
    However this is not typical of 99% of what we all experience throughout the country, in fact, it's almost considered not reality when you think about it. So you have to take a lot of those magazine articles with a grain of salt.

    Since most people don't care to take these DA conditions into affect (and they affect a lot) then comparing ET's among cars all over the country is almost pointless without DA figured in.
    Last edited by Firebirdjones; 09-21-2015 at 10:01 AM.

  17. #17
    Junior Member nukkinfuttz's Avatar
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    Thanks for the link. It had my track and calculated a DA of 2322' and relative density of 93%

    I did check rail pressure after going to the track, it was 58psi. After key was off, pressure drops slightly and by mornin time it was down to like 20. I have not experienced any slow starts yet though.

    As far as my mods, I guess I'm just suprised the car ran exactly the same with and without them. Especially when I see others posting slips after each mod and showing at least some gain. Here I did a batch of mods and gain zero. But even if you discredit them completely, the time and mph still seem to be way below other cars that are completely stock. I mean without running the numbers, that's like 40hp low don't your think? 4-7mph ain't nothing to sneeze at.

    - - - Updated - - -

    Thanks for the idea of injector cleaner, I will do that pronto!

  18. #18
    Veteran 35th-ANV-SS's Avatar
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    How many times have you ran your car? When I first ran mine, I was in the 15's lol (I'm a stick) and after many more passes I was able to get it down into the mid-13's w/o any modifications at all. After headers, exhaust and lid I was at 13.09.
    Boost gets you laid, unless your name is Jon.

  19. #19
    Junior Member nukkinfuttz's Avatar
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    I've ran my turbo 4cyl beretta over 200 passes and it runs 12's. I'm not new to drag racing, and have a pretty good understanding. This is the second time I have raced this trans am. But it's an automatic with no wheel spin, so I'm not sure how much driver error I can really introduce.
    I can certainly see your point about launching a manual and having to shift gears and all. But in this case I just floor it and let off the gas. Simple

  20. #20
    Senior Member kingls1's Avatar
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    1999 Trans-Am, 2012 Sonic

    Me too I was in the mid 14's my 1st one and left the line a little easier second one and went 13.7 and pass 6 it went 13.4 with a 2.0 60 foot @ 104. This past time I couldn't get it below 13.7 with the heat and street tires. Spin, spin, spin. Put on Jeff's tires and still couldn't get lower than 13.4 @102 with a 1.9 60 ft as the heat killed us.
    After about 15 passes I'm still trying to get that perfect pass and I'm hoping that my new drag radials get me there. Point being I have yet to have 2 passes consistent...I will run 13's and next pass boom a 14 for one little mistake. So depending on your skill level at the line I wouldn't beat yourself up too bad. Keep going over things on the car there are a lot of ways to improve your times just depends your budget.

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