Finally got to run the 1/4 mile!

[sidejam]

Here's my timeslip and a vid of the run (I'm car R202):





Keep in mind please that the track is at 3200 ft elevation. There was a stock Solstice GXP that ran a best of 14.6. Assuming he's a decent driver, this gives me an idea what the Sky RL would do at this altitude.

[shabby]

Your 60 footer could use some work, i manged a high 1.9 once. You probably could of gotten a 13.8 if the track was a bit more sticky.

[xxdjfate76xx]

not bad! is that your first time racing?

[sidejam]

Originally Posted by shabby

Your 60 footer could use some work, i manged a high 1.9 once. You probably could of gotten a 13.8 if the track was a bit more sticky.

I was hoping to at least get down to a 2.0 60 ft. The track wasn't as sticky as it could've been. I might just get some different tires to try and get some better launches. We'll see.

Originally Posted by xxdjfate76xx

not bad! is that your first time racing?

That was the first time out with the Sky. My last car was a Ion Redline that managed a 13.7 @ 102 mph on street tires.

[Bogie]

A fifth order polynomial fit to the trap times, differentiated and solved for 60 mph yields a 0 to 60 time of 5.3.

[Ernest]

Nice pass, the lower numbers will come with more passes

[sidejam]

Originally Posted by Bogie

A fifth order polynomial fit to the trap times, differentiated and solved for 60 mph yields a 0 to 60 time of 5.3.

Where can I find that formula? I've wondered about using my mph to figure out my 0 to 60. Pretty cool!

Originally Posted by Ernest

Nice pass, the lower numbers will come with more passes

I still partially blame the altitude for those numbers. All I can really work on is my launches since my Sky is an automatic. The Solstice that was there running a 14.6 that night, was a manual. If I could get my 60' down to a 1.9 or so, I should be good for a 13.7 or possibly even better. I'd like to see low 13's by the end of the season.

[Ernest]

I raced my R/L Automatic at the strip myself. I launched in Low, as high as I could on the convertor without pushing thru the beam, nailed it to the floorboard and never let up, leaving it in low as it would upshift on its' own.

[Bogie]

Originally Posted by sidejam

Where can I find that formula? I've wondered about using my mph to figure out my 0 to 60. Pretty cool!

I'm using a shareware program called "curveexpert 1.3" (Google it and you will find it). The program is generic in that it is a curve fitting program for all types of curves. It is not specifically designed for trap runs.

Plug in the trap data and it generates a polynomial fit. You will also need to put in the start data. Technically the start point is 0 time 0 feet, but double zeros blow up the fit, so do something like 0 time and .001 feet (about a hundredth of an inch head start for the sake of computational sanity).

There is a differentiation mode which will give you velocity (I found this out after doing it by hand a couple of times....about a ten minute process).

Just remember if the inputs are feet and seconds, the output of the polynomial is feet and the output of the differentiation is feet per second, not mph.

[BSRL]

Sidejam, you mentioned a stock GXP ran 14.6, is your car modded? If so , what mods?

[sidejam]

Originally Posted by BSRL

Sidejam, you mentioned a stock GXP ran 14.6, is your car modded? If so , what mods?

Lol!!! I was hoping nobody would ask that... I have very little done, but since you asked:

- Custom Tubes Inc. 3" intake
- Solo Performance downpipe and race pipe
- shortened wastgate arm and bypass one of the wastegate solenoids
- ECU is running a richer air fuel ratio and the torque management software has been removed. It still has stock boost levels, timing tables. TCM is still using stock shift points.
- Set rear tires to 26 psi

Really I haven't done too much yet. I'm not sure exactly what I'll do next. I've noticed that even with the stock timing tables there seems to be a lot of knock retard. Next time I go to the track, I'm going to use 103 octane race gas to see if that makes a difference or to see if the knock sensor is just picking up some other type of noise. If I can get a good trap speed but still have a crappy launch, I'll do different rear tires. If I can eventually get a half decent launch, then I'll probably do a new intercooler to try and help the trap speed.

As it is right now, it looks like the Sky is slow down the last 320 ft of the track. Considering the ET, I would expect the mph to be a bit higher. Also, in the last 320 ft, 2.3 seconds seems a bit slow. I'm not sure why it's slow there, but it's definitely one area that needs to be addressed.

[BSRL]

Originally Posted by sidejam

Lol!!! I was hoping nobody would ask that... I have very little done, but since you asked:

- Custom Tubes Inc. 3" intake
- Solo Performance downpipe and race pipe
- shortened wastgate arm and bypass one of the wastegate solenoids
- ECU is running a richer air fuel ratio and the torque management software has been removed. It still has stock boost levels, timing tables. TCM is still using stock shift points.
- Set rear tires to 26 psi

Really I haven't done too much yet. I'm not sure exactly what I'll do next. I've noticed that even with the stock timing tables there seems to be a lot of knock retard. Next time I go to the track, I'm going to use 103 octane race gas to see if that makes a difference or to see if the knock sensor is just picking up some other type of noise. If I can get a good trap speed but still have a crappy launch, I'll do different rear tires. If I can eventually get a half decent launch, then I'll probably do a new intercooler to try and help the trap speed.

As it is right now, it looks like the Sky is slow down the last 320 ft of the track. Considering the ET, I would expect the mph to be a bit higher. Also, in the last 320 ft, 2.3 seconds seems a bit slow. I'm not sure why it's slow there, but it's definitely one area that needs to be addressed.

hmm, very little, yea. I was wondering what was accounting for the difference in times between you and the GXP. Still have stock tires?

[sidejam]

Originally Posted by BSRL

hmm, very little, yea. I was wondering what was accounting for the difference in times between you and the GXP. Still have stock tires?

Yes, still the stock tires. Without widening the stock wheels or going to a wider 16" rim, options are a bit limited. Possible options are a softer rubber street tire or maybe a Falken Azenis RT-615. Definitely not comparable to a drag radial or slick, but probably better than stock at the very least. Size that I'm looking at now for the stock rim is a 255/45/18 with a UTQG treadwear of about 200 or maybe less.

Did you notice any improved shifting or anything with your transmission cooler? Where did you install it and run the lines? I know the extra cooling is good, but would I notice any sort of improvement? (Sorry, my turn to ask a question!)

[BSRL]

Originally Posted by sidejam

Did you notice any improved shifting or anything with your transmission cooler? Where did you install it and run the lines? I know the extra cooling is good, but would I notice any sort of improvement? (Sorry, my turn to ask a question!)

Not really much improvement, I only added that to get the Werks radiator to work with the automatic transmission. It is installed right in front of the radiator with the lines running underneath.

[Leather]

Sidejam thanks for sharing with us. I have never raced before but would like to try it. What days does Racecity let people test their skillz? I looked online but was unsure, it looks like the cost is $25 a run.

[Bogie]

Originally Posted by sidejam

- ECU is running a richer air fuel ratio

When you do that, does the ECU also correct for all the other feedback sensing that results from the richer mix?

[sidejam]

Originally Posted by Bogie

When you do that, does the ECU also correct for all the other feedback sensing that results from the richer mix?

I would love to be able to answer you, but since I'm not the one tuning it, I don't know. So far, it hasn't thrown any new codes since the tune. Only intermittant code that I have is P0497. But, that's an evap code that I'll get the dealer to look at next time my Sky goes in for service.

I was hoping to get out to the track again this weekend to try some race gas, but, it looks like the weather will be wet and cold. I probably won't get to the track until May 6th or so. I'm going to leave everything the same, just run the race gas to see if there's much change and if the ECU will allow more timing with better fuel.

[TBlueMax]

I love the ending "...fourteen-oh-two, fourteen-oh-two."

Perfect! Congrats and good luck!

[Bogie]

Originally Posted by TBlueMax

I love the ending "...fourteen-oh-two, fourteen-oh-two."

Well, I wasn't going to bring it up, but since someone else noticed....that was kinda sexy sounding.

[sidejam]

LMAO!!! That was my buddy's girlfriend. They were filming some of my runs. I'll make sure to mention this to her.