I went to Cecil County dragway this morning for a test and tune. The car is bone stock, except for the removal of the little flap thingy in the airbox...I wanted to get some runs in before I overhaul my exhaust (about 2 weeks away).

My quickest run was 13.89. 2.096sec 60' time, 100.2mph trap. I hit up a DA calculator after I came home -- it estimates the DA at the time of my runs to be 1563' above sea level, and gives a 13.63sec @ 102.002mph correction.

This still seems slow, from what I was seeing from dragtimes.com stock STRs. I made something like 15 runs -- they ranged from 13.89 to 14.20, varying conditions (DSC on/off, with/without burnout, with/without waterbox, with/without J-gate shifting). The vast majority of my runs were from 13.95 to 14.05.

What kind of times are, or were, you stock STR guys seeing at the track?

(also, what the %&#$ is up with traction control still sort of being on even when it is off?!?)

 

The DSC will always be active to a degree no true way to "disable it" unless you unplug modules think of it as a guardian angel.

You will have adjust your launches to compensate.

Typically I roll into the throttle to get moving then stomp on it and get really good launches without the DSC looking over my shoulder.

STRs are not like civics you can't just stomp on it from a dead stop we actually have torque . Just gotta manage it.

 

Understood, but the traction control was not necessarily the major issue (as I completed several passes with it both on and off, with similar results).

The air filter looked dirty (today was the first time I had seen it). The car has 18000 miles -- let's assume a worst-case scenario, that the filter has not been changed...ever. Can its effect on E.T. be estimated?

 

Phil, The state of tune and adaptive learning of your STR may have played a roll in the track times. First: If you haven't changed the fuel filter, do it now. What was the air filter looking like? If your not the original owner there may be "granny shifting" behavior stored in the ECU's adaptive learning curve causing premature upshifts. If your rear tires are worn the DSC though on the off position, will kick in with more vigor. Change the fuel and air filters, perform a "hard re-set of the ECU to clear as much stored adaptive learning, then teach her about the man your are. When you do an exhaust mod be sure to install hi-flo cats, x-pipe, 2 1/2" pipe, delete stock resonator, dumping it all into flow through mufflers. While you're at it pop on a 1.5 pulley. If all things are in proper working order you should dip into the 12's. In 03 "Car and Driver" tested the STR and felt Jaguars claim of 5.3 0-60mph, 13.5 1/4 mile was conservative...more like 4.8 and 12.9 seconds.

 

hmm...the previous owner bought the car when he was 70 or so, maybe he taught this car bad things (adaptive ECU).

Ok, let's assume the old guy did not utilize the full potential of the STR. On some of these passes, I "manually" shifted (J-gate). Usually, this meant I was able to shift at 6000rpm or just before. Would the old guy's slow driving have a bearing on the *speed* of the shifting, even when I am J-gating? Or, I mean, could he have caused the transmission to take more time in transition (between gears) than there would be otherwise?

 

60' time of 2.096sec isn't that bad, so it doesn't seem like it is traction or the launch that is hurting the trap speed. as mentioned something more like the air filter, fuel filter, or possibly a ignition coil pack.

I've got 58k on my '03 and 2 coils have gone out and boy did replacing them make a difference.

 

Phil, change the filters, hard re-set of ECU, full exhaust mod, 1.5 pulley, low temp thermostat, ect. = low 0-60 and 1/4 mile.

 

I'm on the exhaust issue, got exactly those suggested components on the way. I have no doubt that there will be decent improvement as mods are made...I am more concerned with getting the car to where it should be in its stock condition.

I had a moderate to highly modified Corvette at one time, and it had a severe issue of some kind that caused it to fall on its face after the 2nd to 3rd shift. This car had a 1.65 to 1.70 60' time and still made 13.9, despite having to virtually coast the last half of the track. It saddens me to see the STR have the same ET.

Hopefully I can get this car to where stock STRs are supposed to be. Let me ask about the ECU reset -- is it really as simple as disconnecting the negative cable, waiting a bit, and then holding it on the positive terminal?

 

I just found this from C&D, a pretty comprehensive data sheet and test results for the STR. Imagine my feeling when I saw that they tested the STR at 14.1 / 99mph. Sigh.......

http://www.caranddriver.com/var/ezfl...a38b60a6ea.pdf

While I still intuitively feel like this can be a 12.x-second car (with the usual mods), I can see now why nobody at dragtimes.com has posted a 12-sec time.

 

Here's the link to the CD comparo test data. It indicates the 03 STR ran a 13.8 quarter mile.

http://www.caranddriver.com/var/ezfl...fc6ae1464d.pdf

Full article is here:
http://www.caranddriver.com/reviews/...mparison_tests

 

 

DSC was left on the on position during C&R STR road tests. Riski would concur, after I performed a full exhaust mod I bet I was running sub 5 second 0-60 and 13 second 1/4 mile. With the 1.5 pulley...probably shed another 2/10ths off that. I'm estimating 50 hp and trq was gained from both exhaust and pulley mod. If I don't manage a dyno-ECU tune I'm going for EuroToys ECU tune...another 25 hp and trq. Jaguar certainly detuned the exhaust and ECU on this sleeper.

 

My 05STR's best time was 13.40 @ 105mph bone stock nothing on the car was touched..

remember that the +05's had a few more horsies that the 03's

Your lap times should improve slightly as the tarnny starts shifting harder but mid to high 13's for your 03 sound correct.

Keep in mind for every 10th of a second you improve your 60's foot time it gives you 2/10th over all.

 

I still love this car, maybe even more so than is normal (and possibly even more than bfsgross loves exhaust components!)...but my expectations of it have been lowered somewhat, and that is disappointing to some degree.

Regardless of this, though, the STR remains the sexiest 4000lb car ever. I still intend to make it a beast...but perhaps, instead of it being the kind of beast that climbs the Empire State Building and has films made about it, it will be a slightly smaller one that is more comfortable causing havoc around slightly smaller buildings.

 

Oh dear, Phil, Phil, Phil...When you do a full exhaust mod (exhaust manifolds back), fresh fuel filter, K&N panel filter, hard re-set of the ECU followed by agressive driving with DSC disengaged...watch out pal, cause you're in for a rude awakening. I know it as a matter of "fact" you'll not recognize the ripping performance of your STR as it once was. In fact, you'll sit back in the seat of your STR laughing thinking of these words and you'll immediately post me while an inseparable grin runs from each corner of your mouth. Throw in a 1.5 pulley and a low temperature thermostat and your off to the races. How do I know this will happen Phil? I "was" in the same position as you..."She has 400 hp and 410 ft/lbs. of trq., but what gives?".

 

I was reading more about the ECU reset right before I typed this, and it is exciting me already. I am thinking I should do the reset at an interstate rest stop or something, so I can immediately make several 0-100 runs (so as not to taint the ECU by having to drive through residential neighborhoods)

 

That a boy Phil...now ya got the good ole "Git Er Done" mentality. Don't forget: Before launching turn off DSC and throw her into "Sport". Drive her around in an agressive mannner for a few hundred miles. Though you'll notice some difference, the hard re-set does much more good when the exhaust is opened up. At this juncture you'll be enticed to perform a full exhaust mod and so-forth. It's humbling to know the STR's ECU happily adapts to changes in free-er flowing parameters; allowing later upshifts and self re-mapping with more fuel and spark in mind. My STR shifts from 1st to 2nd at 5500 RPM. I'll be performing a new hard re-set this week in trying to eliminate the DSC from intervening. Phil, yes she has sexy lines...but hidden underneath is a bitch with a deadly bite. It won't be long when you're the stalker.

 

This hasn't always been the case after your initial reset, has it? My STR does this already, but I know the redline is slightly above 6100...now I am worried a little.

 

Phil, redline is set at 6250 and don't bother trusting your tach. When in "Normal" mode, the TCM factory setting shifts her from 1st to 2nd at 4700 RPM and 2nd to 3rd at 5500 RPM. You'll notice that when at a stop, using a quick but gradual depression of the pedal won't summons the DSC to intervene. Many an STR owner achieves quicker 0-60 and 1/4 mile time using this technique rather than the good ole "Pedal To The Metal" technique. Along with a full exhaust mod, 1.5 pulley, low temp. thermostat; in "Sport" mode I taught my STR to do 5500 RPM 1st to 2nd shifts while punching it, not feathering the pedal. As I mentioned earlier, I will cont. to teach her new tricks.

 

Don't guess and estimate and add hp together that may or may not be there. Just take it to a drag strip already.