Here are my YouTube videos of my 991 Turbo S with GIAC Stage 2, Europipe and IPD plenum running race gas (Torco 108) and the GIAC race gas tune file defeating a 12c, Huracan, Aston Martin DB9 and a stock 991 Turbo S.

This was filed at Albuquerque Dragway during goldRush Rally 7. The DA was an incredible, time-killing 9000 feet. My car never lost a match.

My car vs. 12c:


My car vs. Huracan:


My car vs. Stock 991 Turbo S:


My car vs. DB9:

 

What was your best 1/4 mile ?

 

Best time was 11.2 seconds. The consistent times were 11.3 seconds. The conditions were horrendous for drag racing with a density altitude of about 7700-9000 feet. The dragstrip is at almost 5000 feet of elevation and the temperature ranged from about 82 to over 90 degrees.

If the race had been run at sea level my times would've been somewhere around 10.7.

My car was running Michelin pilot super sports rather than an R compound tire or drag radial which would have helped on launch. And I'm running an exhaust with high flow cats (Europipe) rather than catless.

The US record holder in the quarter mile for this car, Karl, was running R compound tires, the Michelin pilot sport cup 2s, and a Tubi catless race exhaust. I'm guessing those mods would be good for lowering the ET .1 or .2 seconds from the best run that my car could put up. I never considered running the pilot sport cup twos on Goldrush Rally given that they are not great in the rain and I knew we would be experiencing rain during the rally which we sure did in the eastern leg (which took us through Texas, Louisiana, Mississippi, Alabama and Florida: from Austin to Miami).

I ran many many times which showed me the effects of both race gas and heat soak. My first five or six runs were on pump gas with the tank virtually empty. My first few runs were 11.3 which quickly jumped to 11.7-11.9 due to heat soak. Then I added ten gallons of race gas (Torco 108-which is their equivalent fuel to MS109) and switched my tune to GIAC's race gas tune file. My times then fell to 11.2-11.3 for the rest of the event.

There is no question that had I been running the Torco 108 and the race gas tune file on my first run when the car was cold it would have broken into the 10s. Given the extreme heat and altitude only two goldRush Rally cars broke into the ten: Alejandro's Porsche 918 and Ben Chen's Bugatti Veyron's.

 

In this post, I analyze, based on the time slips, the effects of heat soak power loss and then the addition of top shelf race gas (Torco 108 -- the Torco equivalent of VP's MS109) paired with the GIAC Stage 2 race gas tune subfile.

Here are the pictures of my time slips. My best run was, of course, on race gas with the GIAC Stage 2 race gas tune file activated. It was an ET of 11.2743 with a trap speed of 124.10. According to the dragtimes.com density attitude correction calculator, the DA at the time of this run (6:53 pm local time) was 7,721 feet (the track elevation is 4943 feet and at the time of this run the air temp was 82 degrees F, the barometric pressure was 29.87 inches and relative humidity was 31%).

Running that through the correction calculator yields at sea level ET and trap speed of 10.796 at 129.377 mph. See http://www.dragtimes.com/da-density-...ect+ET+and+MPH

The result would have been a lot faster if the car were cool and running race gas.

These time slips show the brutal effect of heat soak on the performance. I am car number 52 in the slips. The car's performance mods: GIAC Stage 2, Europipe exhaust with 100 cell cats, IPD Plenum, BMC filter and Champion Race Diverter Valves. Tires were Michelin Pilot Super Sports in OEM sizes riding on ADV005 track spec CS wheels with titanium fasteners in OEM sizes (ADV1's top of the line and lightest wheel with a retail price of about $15,000). Car has no suspension mods.

All runs were using launch control with spoilers retracted and the PDCC button off to allow for the most weight transfer on launch to the rear wheels. The car was emptied of any luggage or extra weight. The AC was off and everything electrical that could be turned off was turned off. Windows were closed and, to minimize drag, I did not mount GoPros or anything else on the outside of the car.

The first five runs were on pump gas.

The first run, when the car was cool, was a 11.3751 seconds at 121.95 mph.

In the second run, the numbers worsened to 11.5352 seconds at 119.94 seconds.

In the third run, the numbers worsened more to 11.7259 seconds at 11.7259 seconds at 120.42 mph.

The fourth run was the worst of the day: 11.9387 seconds at 117.65 mph. This is just massive soak power loss -- an ET .5636 seconds higher and 4.3 mph slower than the first run -- both on pump gas.

The fifth run wasn't much better: 11.7330 seconds at 118.67 mph.

Then I added the Torco 108 race gas, switched to the race tune file and things got much faster.

The 6th run (1st on race gas): 11.3079 seconds at 121.49 mph -- a run even better than when the car was cold on pump gas. This run also had my best 60 foot time of the event -- 1.6847 seconds.

The 7th run (2nd on race gas): 11.3568 seconds at 122.78 mph.

The 8th run (3rd on race gas): 11.3752 seconds at 122.88 mph.

The 9th run (4th on race gas): 11.3296 seconds at 122.55 mph.

The 10th run (5th on race gas) was my fastest: 11.2743 seconds at 124.10 mph.

What this showed me is that the race gas essentially restored the power than I lost to heat soak. Unfortunately, I never got to run the car on race gas when it was cool. Had I been able to do so (the race gas only got delivered to the dragstrip halfway through the event) the car would certainly have broken into the 10s.

 

The stock Porsche 991 Turbo S was the other car in the slip at 6:12 pm, running at 12.37 seconds. My ET was 11.30 -- a full 1.07 second faster than the stock 991 Turbo S -- virtually all of the gain occurred in the first 1/8 mile.

The Huracan was the other car in the slip at 6:40 pm, running at 12.53 seconds. My ET was 11.37 seconds -- 1.16 seconds faster.

The 12c was the other car in the slip at 6:46 pm, running at 12.61 seconds. My ET was 11.32 seconds -- 1.29 seconds faster.

 

Wow , nice result comparing to the other cars . Hurucan and mp4-12c are no joke

 

I have watched the video's a few times.

I am really glad you are enjoying your car and your times are very impressive. Having said that most of your competition looked like they really weren't that agressively trying to race or they were not very good at the drag strip so not really sure the beating up those cars holds a lot of wait. I think there are plenty of threads that would show those races a little closer than these.

Still your car is very impressive and you have done lots of nice unpgrades.

How has the reliability been so far? How is the car now. With a lot of modding and the reason I am waiting on this car it always seems to make the car less than perfect. I mean you start getting little squeaks, creaks and unwanted "non factory" characteristics. Have you had any of that yet?

 

The Huracan driver had a passenger and kept his car idling during an over 20 minute period before our race when the track was closed due to debris. I shut off my car and opened the engine cover up. That might've helped a little bit but certainly wouldn't explain that huge margin. It should've been closer but for some reason it wasn't. When I was on pump gas a Huracan (which was cool) beat mine (which was hot from many runs) in a drag race at the Driving Force Club runway event.

The 12c driver is an expert driver and experienced. As was the stock 991 TTS driver.

As far as reliability my car has been rock solid reliable. The GIAC tune feels completely stock except when the turbos come on. Idol and throttle tip in a really unaffected in terms of smoothness. The big difference with the tune is the amount of acceleration once the turbos come on. There've been absolutely no issues with the car at all. My concern about reliability is why I went with the GIAC tune instead of some custom tune from a tuner. GIAC sells so many tunes and, as such, has to make them safe so they don't start blowing up engines which would blow up their big business. My car has about 9000 miles on it and I've owned it since December. It performed flawlessly at goldrush rally going coast to coast with no issues.

 

Thanks for that. What about the suspension and exhaust? Rattles, creaks, rubbing, doesn't look perfect at the tail pipes etc etc.

 

Haven't done a thing to my suspension. Haven't changed shocks, springs and have kept OEM wheel and tire sizes albeit it in warm months I run on super light ADV1s which perform perfectly other than the center caps tying to pop off when the brakes get super hot during track or drag race days.

My exhaust functions perfectly. In terms of aftermarket exhaust quality if you ask Porsche mechanics they will tell you that Europipe's build quality is as good or better than OEM. Seriously not one exhaust issue at all. Tail pipes look exactly the same because Europipe uses the OEM tips.

What can I say. My car functions perfectly with the mods. I have no issues. My only issue is heat soak power loss when I do multiple hard runs at events which is a function of the increased heat from the increased boost of the tune and the ECU/tune dialing down the boost/timing at high RPMs to lower the intake air temperature so as not to fry the turbos. That's no big deal in terms of the car's functionality. Not an issue in regular driving either. No limp home mode or drivetrain malfunctions (unlike so many modded and even stock BMWs when pushed hard). Perfectly smooth tune. Just not quite as fast at high RPMs as the initial take off on subsequent hot runs but still faster than stock.

 

As you know Im GIAC stage 2 & EP as well. What was the final margin on the tts?

 

In a post above I stated with my margin of victory was against the Huracan, 12 C and stock 991 Turbo S--all were more than a second.