[Tuned335i]

Datalogs are fun to examine so....

Went to Speedworld Dragstrip last night, northwest of Phoenix to try to redeem my disappointing results at Firebird Raceway on January 11 (13.504@108.12). Here's the car configuration and atmospherics:

Car
2007 E92 335i
6AT, DS mode, DTC on (one push)
Stock except for PROcede V2.0.2, 12-19 Map (because it works flawlessly...)
Default 90% User Torque Settings
95-96 octane race gas mix
Gas tank nearly full
19" Michelin PS2 P265-30's, 29psi

Atmosphere/Location
59 degrees F, 54% Humidity
Approx. 1680 feet elevation

The only significant change I made last night from my previous trip to the dragstrip was to reduce the air pressure in the rear tires. People have said that lowering the psi in the tires would have no effect because the sidewalls are so stiff already. But lowering them to 29lbs from the car manual's recommended psi of 39 changed everything.

My best run (my second) of the night was against a modified (I assume) Chrysler Crossfire which got me off the line and ran a 12.705@109.641, beating my best run to date of 13.002@109.545 with a 60' time of 2.05 sec. I think without my wheelspin off the line, I could have taken him. Unfortunately I didn't start the datalog when I rolled up to the lights. The following run was a mess due to wheelspin so I'm not bothering to include it here.

So here are the datalogs from runs 1, 4, 5, 6, & 7 at last night's race. On every run I had traction control intervention which kept my 60' times above 2.1 seconds (except for my second run), and in a couple of cases, 2.3 seconds. Within each datalog is the E.T. and trap speed. I know this car is easily capable of high 12's at 110-111 with no other mods, like many other 6AT cars have run with V2 only. Looks like the psi is right where it should be...

Last night I learned a lot about launch in the car at the track. I'm confident next time out will result in a 12.9x or better at 110mph+, maybe in a week or two.

Cheers!!!


Run #1



Run #4



Run #5



Run #6



Run #7

[e90AW335i]

The lowest boost got the best time?

[Driver72]

Where did you do these runs?

And why only 90% default settings if you have 95-96 Octane race gas mix??
If you are going to spend the money to put race gas in, take the few minutes to get your boost levels up to at least 15 psi.

[dr.roro]

Why don't you try some runs with the DTC off?

[Tuned335i]

Originally Posted by kyleh4852

The lowest boost got the best time?

Good question. Perhaps. Unfortunately my best run by far was the run I screwed up and didn't datalog (the run against the Crossfire). The trap speeds are fairly consistent. Not much time between runs, not more than 10 minutes.

Originally Posted by Driver72

Where did you do these runs?

And why only 90% default settings if you have 95-96 Octane race gas mix??
If you are going to spend the money to put race gas in, take the few minutes to get your boost levels up to at least 15 psi.

They were done at a 1/4 mile dragstrip called Speedworld Dragstrip northwest of Phoenix about 1,680 feet elevation.

Yeah, I thought about bumping the torque settings. The race gas mix is mostly for protection and a paranoid/superstitious belief that it has something to do with the fact that I have never had a limp mode. In 4th gear it looks like I'm at the low 14psi, I can probably stand to increase it 2% or 4%. I'll do that for the next trip to the dragstrip and see what happens.

Originally Posted by dr.roro

Why don't you try some runs with the DTC off?

I'm going to try that next time. I think I can modulate the throttle well enough to make a little bit of wheelspin work for me, rather than have the traction control intervene and cut the power completely (killing the boost pressure at the same time...)

I was pretty happy with the 13.002@109.545 and the 2.05 60' time. The crossfire had a 1.90 60' time and left early which accounts for why he was about a car length ahead when we got to the lights. I was curious as to what mods that car had but didn't have an opportunity to talk to him in the pits.


All in all, I was really happy with the car's performance. I was hoping for either a 12.xx or 11x.00 slip last night, but there is always next week...

[DrewKo]

You definitely need to do some of the runs with DTC completely off or at least with DTC lighted. You'll have a tough time breaking into the 12s with the computer slowing down your acceleration.

[Tuned335i]

Originally Posted by DrewKo

You definitely need to do some of the runs with DTC completely off or at least with DTC lighted. You'll have a tough time breaking into the 12s with the computer slowing down your acceleration.

Thanks, I'm going to try that next time out, either 2/2 or 2/9. All my previous runs were with DTC lit. The track I went to this time only had 5 or 6 cars in each of the 5 lanes that they were using so getting several runs in to work on the launch was easy. At the other track, with 30-45 minutes between runs, it was pretty hard to work on technique.

[stressdoc]

You will be wearing a helmet next time -- assuming the track has a sub-13 rule. LSD would be nice. PS2s are expensive drag tires! A set of lightweight 18" rims and DRs might not be a bad investment.

[Supramano]

why did you shift so early in first to second gear??

[Sniz]

Originally Posted by Supramano

why did you shift so early in first to second gear??

good question! Looks like you were shifting out of 1st between 3000 and 5000 rpms.....what gives?

Also, I always ran my best times w/ DTC fully off, but I have a manual so it may be different w your auto.

[Tuned335i]

Originally Posted by stressdoc

You will be wearing a helmet next time -- assuming the track has a sub-13 rule. LSD would be nice. PS2s are expensive drag tires! A set of lightweight 18" rims and DRs might not be a bad investment.

Absolutely! Actually the two tracks in Phoenix are NHRA tracks and adhere to their rules, meaning the driver of any vehicle running 13.99 or quicker must wear a SFI-approved helmet with a SNELL 2000 rating or better. I've had a helmet for every run. LSD isn't in the future for this car, but 18" + DRs is a possibility!

Originally Posted by Sniz

good question! Looks like you were shifting out of 1st between 3000 and 5000 rpms.....what gives?

Also, I always ran my best times w/ DTC fully off, but I have a manual so it may be different w your auto.

All runs to date have been in DS mode shifted automatically. That early shift is when the DTC kicked to arrest the wheelspin, killing the power. I think in each case it also shifts to 2nd, which is why it looks like I shifted early. That's what resulted in my long 60' times.

Next time out I am going to try a couple of passes with DTC fully off, and modulate the throttle to control the wheelspin...

[Trill335]

Originally Posted by stressdoc

You will be wearing a helmet next time -- assuming the track has a sub-13 rule. LSD would be nice. PS2s are expensive drag tires! A set of lightweight 18" rims and DRs might not be a bad investment.

My local track doesn't enforce anything. Atleast they didn't last season. I witnessed a guy run low 10's in an Automatic C6Z06 with a wife beater, some cargo shorts, flip flops, and minus the helmet mod! He looked really cool going down the track...let me tell you!

He came back around afterwards and cracked the nitrous bottles open...dressed the same way! Gotta love Alabama!

[Tuned335i]

Originally Posted by Trill335

My local track doesn't enforce anything. Atleast they didn't last season. I witnessed a guy run low 10's in an Automatic C6Z06 with a wife beater, some cargo shorts, flip flops, and minus the helmet mod! He looked really cool going down the track...let me tell you!

He came back around afterwards and cracked the nitrous bottles open...dressed the same way! Gotta love Alabama!

That's insane but funny. They must be self-insured or something!!

BTW the E.T./trap in your sig is awesome. Was that on DRs? What mods?

[Dan335i]

In NY,you have to wear a Snell 2000 approved helmet to run period!

[LODOSS]

You should just start in 2nd then.. it might save you .5 second.

[Trill335]

Originally Posted by Tuned335i

That's insane but funny. They must be self-insured or something!!

BTW the E.T./trap in your sig is awesome. Was that on DRs? What mods?

It was hilarious to see in person. I'll P.M. you my info as to not intrude.

[jmenge]

Originally Posted by Trill335

My local track doesn't enforce anything. Atleast they didn't last season. I witnessed a guy run low 10's in an Automatic C6Z06 with a wife beater, some cargo shorts, flip flops, and minus the helmet mod! He looked really cool going down the track...let me tell you!

He came back around afterwards and cracked the nitrous bottles open...dressed the same way! Gotta love Alabama!

Wow, what probably looked even cooler is how he managed to get an automatic c6z06 since they only come in manuals ...

[Trill335]

Originally Posted by jmenge

Wow, what probably looked even cooler is how he managed to get an automatic c6z06 since they only come in manuals ...

I figured some self professed know it all would post the above; thinking he or she had unlocked the key to world hunger! The car is a highly modded C6 ZO6 out of Texas. It has an Automatic transmission, Drag Radials on CCW's, Nitrous, and the usual bolt-ons and tune.

You speak as though you've never heard of people modifying Z06's, Cobras, and Vipers with Auto transmissions.

Stay tuned I'll see if I can't get some pictures for you; this way you'll close your mouth and we can all go about our business.

[Trill335]

Originally Posted by jmenge

Wow, what probably looked even cooler is how he managed to get an automatic c6z06 since they only come in manuals ...

Why don't you take a look over on www.corvetteforum.com Once you get there Automatic Z06. Enjoy the findings. RPM does the conversions for quite a bit less coin than others. There is even a guy that has the new transmission with the paddle shifters in an 07 Z06. Dealer did it for him for $10,000.

Amazing what a little bit of research finds.

I personally saw the Texas car on the track making passes. Very quick car...I'd love to have one set-up like that! The owner had a highly modified SRT-10 before the Auto C6 Z06.

[jmenge]

Wow, and I'm the smart-ass? Lol, easy there man. I know quite a bit about corvettes thanks, I own a c6 with many mods making over 500rwhp. My comment was that they never produced any automatic z06's which i stand by. Of course you can mod a vette just like any other car. Not sure why anyone would put an auto in a z06 to only run 10's. Ranger and another driver have both hit 10's bone stock in a Z. Hell my car is just a standard c6 and I run 10.8X's on just drag radials (MN6 manual). But anyway I'd like to see pics of the car you are speaking of that ran low 10's in alabama. Just curious, I know most of the guys on the c6 boards. Take a chill pill BTW, my comment was meant in jest just like the manner in which you presented your recollection of said event, lol.

[XLR8MF]

Anyways, that is so funny you just posted this up. I just did my first log and not sure what to think of the results. I have been meaning to get in contact with you Tunned335i. Nice runs. I would certainly run with DTC off and play with how much or how little to hit the gas with your foot in first or just start from 2nd. I know you went to Firebird in the past so how was this new place. PM me and next time I will go with you. Oh yeah, with race gas all of your runs are under 15psi, increase your torque settings and you should take the crossfire. Good luck.

[Tuned335i]

Originally Posted by XLR8MF

Anyways, that is so funny you just posted this up. I just did my first log and not sure what to think of the results. I have been meaning to get in contact with you Tunned335i. Nice runs. I would certainly run with DTC off and play with how much or how little to hit the gas with your foot in first or just start from 2nd. I know you went to Firebird in the past so how was this new place. PM me and next time I will go with you. Oh yeah, with race gas all of your runs are under 15psi, increase your torque settings and you should take the crossfire. Good luck.

Thanks! Since those runs above I have bumped my settings to 96% but haven't really had a chance to do any datalogs. Right off the bat my boost was down and the car was noticably slower but I kept driving with it and it seems to be back. The rain over the weekend kept the car in the garage, so no logs yet.

Speedworld was much better than Firebird, if for no other reason than I got 7 runs in an hour, versus 2 runs in an hour and a half at Firebird. The distance is exactly the same from where I am (L101 & Tatum). In fact, I probably won't go back to Firebird unless there is a really good reason. I'll PM you.

There really isn't any place to get a full 2nd-4th redline logs around here. I'm gonna have to settle for some 3rd gear pulls to see what's up with the boost.