[Calvin@Vishnu]

Got this datalog sent to us this morning from StartupJunkie who, despite the 93-94 deg temps, recently broke his personal best trap speed. He was a few hundredths of a sec away from breaking his best ET but had to cut short his night when an aftermarket brake line failed at the end of the track

Reading a datalog is important when it comes to seeing how your car is running and knowing if something is holding you back. Contrary to popular belief, there is no such thing as a "ringer" production car. Sure, some cars are slightly stronger than others all things equal. But only slightly. The vast majority of power differentials between similarly modified cars comes from all the other things that are not being held equal. And the biggest contributor is fuel/octane. And it's also the most commonly hidden mod

Here is the datalog of StartupJunkie's 11.59@124.6 run. This car is just a standard 6AT Sedan running basic weight savings (passenger seat, light battery) with full Stg 3 mods, Methanol injection and drag tires/17" Kosei wheels on 110octane:



Things worth noticing:

1) Maxed out, the stock turbos can provide some seriously power/boost. At nearly 100% duty cycle, the turbos can support 19psi as high as 6500rpm! And they seem to do this with reliability (many many runs and no failures so far).

2) The turbos can also build so good boost at the launch (using the Procede's launch control). This day, the drag radials were corded so the best 60' the car could muster was just under 1.7. With fresh rubber, it cuts 1.59-1.65s consistently. No wheelspin.. just swats and goes.

3) Air intake temp starts off at 117 deg F (although it's mislabeled as C on in the datalog) which isn't surprising considering that ambient temps were around 95F. What is cool is to see methanol drop temps all the way to 80F by the start of 3rd gear. And then stay there for the rest of the run. This is will our PnP meth injection kit running the optional M10 jet running 90/10 meth/water mixture. Without methanol, intake temps would have probably rose around 20F instead of dropping nearly 40F. That's a HUGE benefit. Especially in the higher gears where a non-meth car starts to heatsoak and load power quickly.

4) AFR is rock solid at 12.5:1 at full boost with blips only at the upshifts.

5) Applied throttle is 100%. You would be surprised how many datalogs I see where applied throttle drops to 70-80% when the car accelerates, forcing the foot to lift slightly off the gas pedal.

6) CAN dbw throttle (actual throttle blade) is full open, only closing slightly for the 1-2 and 2-3 shift since RPM was higher than ideal (6500rpm).

7) There are no major timing drop outs under full boost. With the exception of the start of 3rd gear, timing doesn't get lower than 10 deg and ramps up to ~13.5 deg. If temps were colder, I'd guess that even 3rd gear would start off at 10deg as well instead of 7deg which indicates some minor knock retard. And this is on 110oct fuel with methanol.

8) This run is fast as just about any stock car available today (except maybe the ZR1 and a handful of hyper exotics). And all of that is due to careful car prep which boils down to only:

-Running the right mods
-Running the best possible fuel
-And the most aggressive map that can be supported with the above. In this case, the standard v4 map running 100% Start Boost (20psi) and 0% Ignition Corrected (autotuned).

Simple as that

[Mr. 5]

100% duty cycle!!!

[Jeff@TopGearSolutions]

Damn Auto's have it easy LOL

[Calvin@Vishnu]

Originally Posted by JPSlick

Damn Auto's have it easy LOL

Yea but the funny thing is that they are lightly slower than a well-driven 6MT. The really only inherent advantage they have is at the launch where they can cut crazy good 60's. But from any rolling start, they aren't the best choice if you know how to shift quickly.

[dzenno]

100% duty cycle?? I've never been able to get that to happen so far..

[Calvin@Vishnu]

Originally Posted by dzenno

100% duty cycle?? I've never been able to get that to happen so far..

You probably don't need it to, in order to hit the 3000-5500rpm boost target. StartupJunkie's car, like ours, has the early turbo wastegates that were softer than the updated replacements. So autotuning compensates for it by scaling up the start DC table by another 5-6%.

[Ilma]

+100 on having good octane on tap.

I run a stock setup except for DCI and VK intercooler and once autotune came on the scene, I found that I had to drop my boost to 12.5-13 psi in order to get a half decent timing curve since autotune was taking ignition correction down to basically zero.

I Dumped in 3 gallons of 110 octane for the first time yesterday and filled up the rest of the tank with pump.

My timing curve blew me away....never went below 10 degrees of advance running 14 psi of boost.

So lesson learned for me - even us stock guys need to match boost to octane and watch those timing curves in order to optimize our tunes - even if they are at lower boost levels than the modified cars.

[hotrod182]

Where do you get 110 octane fuel, is it still unleaded?
I have just been using the 100 octane unleaded pump gas, and the small basic meth nozzle my last few times out. I hope to play around with meth mixtures/pressures are little more this time around.

Does StartupJunkie's car have stock rear cats/exhaust?

[Ilma]

Originally Posted by hotrod182

Where do you get 110 octane fuel, is it still unleaded?
I have just been using the 100 octane unleaded pump gas my last few times out.

Nope.....I found a competition race fuel distributor local to me - 15 minute drive.

110 octane - no lead

http://www.proracingfuels.ca/Product_MARK2.html

[TakeOne]

meh, probably just a fast track
Congrats startup, pushin some serious power there.

[datbimmerdoe]

good recipe.

[Former_Boosted_IS]

Originally Posted by Ilma

Nope.....I found a competition race fuel distributor local to me - 15 minute drive.

110 octane - no lead

http://www.proracingfuels.ca/Product_MARK2.html

How orange is the fuel? Do you have issues with it staining anything?

[Clap135]

Originally Posted by TakeOne

meh, probably just a fast track
Congrats startup, pushin some serious power there.

Actually sac is notorwious for inflating traps. Your sarcasm was actually spot on lol. A good fast track is one of the main ingredients to this recipe.

[themyst]

My lord that is one pretty looking log. Congrats StartupJunkie.

[Ilma]

Originally Posted by Former_Boosted_IS

How orange is the fuel? Do you have issues with it staining anything?

I was worried about that myself, but the manager stated that it burns clean and won't leave a residue like MMT does.

The different octane ratings seem to have different colours added for ease of identification.

It's time to replace the plugs this weekend, so I will have a look for orange residue on them.

Don't forget that my dilution factor is pretty high.

3 gallons of 110 octane and then filling the rest of the tank with regular pump gas to full.

[Former_Boosted_IS]

Originally Posted by Ilma

I was worried about that myself, but the manager stated that it burns clean and won't leave a residue like MMT does.

The different octane ratings seem to have different colours added for ease of identification.

It's time to replace the plugs this weekend, so I will have a look for orange residue on them.

Don't forget that my dilution factor is pretty high.

3 gallons of 110 octane and then filling the rest of the tank with regular pump gas to full.

Oh you don't run it straight? I would want to run it straight if I ran it.

[Ilma]

Originally Posted by Former_Boosted_IS

Oh you don't run it straight? I would want to run it straight if I ran it.

Former...... as you can see from my log above, I am only running 14 psi = basically a stock setup since I have stock downpipes and stock exhaust.

I don't track my car.

I was just experimenting to see if I could improve my timing curve by running a few gallons of 110 octane with each fillup and this seems to have given me a really nice safe timing curve....whereas before, I would have to drop boost to 12.5-13 psi to get one.

Once the car is out of warranty, I will probably go with meth, but for now I feel much better about having a bit better octane in the tank.

[dzenno]

Ilma, did you ever look at the plugs after this gas? I'm thinking of getting some of this orange stuff for this weekend...