ToothDoc

Do you have your VDIM disabled completely? Have you tried to burn out just a little to clean the dirt off the tires? If you do these two things, the only reason I can think of your high ET is temp/pressure/humidty/elevation. That's it. I have had as high as 13.97 and 99.4 mph just for going on a 80 degree day with high humidity even though I had 1/4 tank instead of my 1/2 tank!

Gernby

iTrader: (1)

I just now realized that your 60' time is faster than anything on DragTimes.com even with R compound tires! That's awesome! However, I'm really confused about your ET being so slow (relatively). How could your 60' be great, trap be good, and ET be slow??!?

combfilter

iTrader: (3)

Personally I think this car right here is the most impressive IS regardless or stock or mod. These 60' times are beyond good. Stock tires and Stock car hitting those 60's and those trap speeds.

He's trapping higher then me, and sub 60' better then I have ever even come close to.

tt061880

that is an impressive IS, I'm so sad that he dethroned me. I'm not longer the fastest stock IS in the country anymore, well I guess I'm still the fastest Lux package haha . Anyway good job bro, it's good to see another IS hit sub 13.5 stock. A lot of people thought I was lying when I told them my stock IS ran 13.49@103.8 because it seem unreal. As more cars hit the track, I noticed the base IS350 usually run faster than the sport package and luxury package for some reason. Maybe because they are lighter?



trap speed is something I never understand, many times I get a good trap speed but then ET is slow. My fastest time of 13.49 has a 2.13 60', figure that one out.

caymandive

iTrader: (2)

I agree. Would be interesting to see what other IS350's can run at this track.

ToothDoc

Hey thanks guys for the awesome words. Honestly, I'm still scratching my head on how this actually happened. I think lowering the PSI on the rear will lower your overall trap speed due to higher rolling resistance. In addition, since this is my daily driver, I would think that keeping the tire pressure constant would give me a more even constant pressure tire patch than just suddenly lowering the PSI right before going to a track. Plus... I didn't want to have to lower my psi and drive home with low pressure tires or get my fingers dirty from the brake dust (please, no comments on the last one - lol). I know the lower PSI = better times has been beaten to death and in the guys with a lot of experience, they always seem to agree with that. BUT, the ONE time I did lower psi, I actually had worse ET and trap so that's why I didn't do it.

Now, I do have 23000 miles - maybe my IS is more broken in? I drive it about 20-30 miles everyday and a day doesn't go by that I don't floor it. Also, I bought my IS over 2 years ago with almost 100 miles on the odo - the sales guys were probably all taking it for a joyride before me. I also never broke in the engine - just drove it hard from day 1. Maybe that has something to do with it?

I did run twice previously in 06. Back then, I was only able to muster 13.8-9 with 100-101 trap and 2.08-2.11 60 feet. BUT, I have it written down that it was 82 that evening and humid. It was so humid that after dropping down to 70's, it was starting to get foggy (dew point was 70's). Back then, the car had less weight - 1/4 tank instead of 1/2 tank+stuff.

Why didn't I go with less fuel and junk? I truly did not expect to hit these numbers. I went for fun to see if an extra 15,000 miles made it faster. If I knew I was going to set some record, I would have had 1/4-1/8 tank and emptied out all the stuff (but still keep jack and spare so I can still be called "stock").

Now, one LAST thing that I think helped me was that I never shut the engine down for the runs last weekend. Previously, I'd open my hood, shut engine down, to prevent heat soak. This time, I'd just paid, and ran, and ran, and ran. I actually did 10 runs in a very short amount of time.

ToothDoc

Here is an actual list of my runs:

Run 1: 10:31 am vs. CLS55 - I beat him cuz he spun for 18 seconds
2.064
13.622
101.85

Run 2: 10:35 am vs. CLS55 again - he beat my et by <.1 cuz he spun again
2.014
13.515
102.57

Run 3: 10:38 am vs. C5Z06 He spun his start.
1.984 2.274
13.444 13.012
102.57 again. 109.3

Run 4: 10:45 am vs. WS6 I beat him - bad launch
1.977 2.320
13.492 14.280
102.09 98.87

Run 5: 10:49 am vs same WS6 - I beat him again
1.980 2.287
13.447 13.892
103.08 103.61

Run 6: 10:55 am vs GT500 I brake launched too much and spun too much
2.041 2.008
13.526 13.069
102.33 109.26

Run 7: 11:00 am vs. CLS55 again - he finally hooked up
1.969 1.899
13.448 12.358
102.23 114.16

Run 8: 11:04 am by myself - no burnout and no brake launch. massive spin
2.520
14.457
101.54

Run 9: 11:09 am vs. ZR1 with DR and skinnies - he KILLED me
1.956 1.709
13.459 11.412
102.41 124.53

Run 10: 11:18 am vs. some american classic - but I had to idle extra 5 minutes for them to remove junk off the track - previous car lost some part and my cooling fan was running at start.
1.998 1.831
13.535 12.591
102.01 109.71

47 minutes = 10 runs. I think keeping the oil warm, the tranny warm, and car moving help keep everything running loose and gave me good times. But I still think the biggest factor was track prep for the 60' times.

Gernby

iTrader: (1)

You really need to post that 1.956 60' run on DragTimes.

combfilter

iTrader: (3)

again, all I can say is that I am very impressed with the stock IS you have. Absolutely great!

VikH

iTrader: (5)

Tooth have you thought about going to Byron? I have heard people like going there as well. Let me know if you want to meet up at the track one day. I haven't been out to drag the car yet.

ToothDoc

I didn't want to fill up the dragtimes website, but since you asked... I put it up there.

ToothDoc

I'd like to go one day - but I *RARELY* plan such events due to work, wife, kid, and weather. I'm actually thinking of going this Sunday to Great Lakes again (it's closest to me - about 35 minutes). This time I want to do a run and while video is recording, I want to show timeslip and then video my car to show the tires, tire pressure, and the spare and jack and the engine bay to show no intake etc. I haven't gotten any naysayers, but I myself, still find it hard to believe my own 60' times!! So I want it on tape this time. BUT, with my bad luck, it'll rain Sunday or the DA won't be as good. Oh well I'm praying for no rain.

ES3

I would think whatever resistance is added with lower PSI, it's more than gained by better traction with less PSI at launch, no?

Strange, I'd think a cooler engine would be a faster engine? Why do you think that played a role?

Oh yeah, you may have addressed this, but do you run your street tires through the water and brake torque them before you run to heat them up and get the dirt off? I typically avoid the water, but do spin them a bit. Not sure how much of a difference the heat makes on regular street tires???

At any rate, thanks a bunch for the info!

Gernby

iTrader: (1)

A cooler engine is faster, but the coolant gets really hot when you idle, or shut it off.

tt061880

cooler engine makes more power. If you want the coolant to get cooler before the run, have your heater on Max. The heater use hot coolant hence it cools the coolant down. In my previous car with full programmable ECU, it gives me realtime stats of all the sensors. By turn on the heater the coolant is at least 10*F cooler.