Apr 7, 2017

Ultima GTR - Now Built and Wildly Fast

Building and assembling your own vehicle is immensely satisfying, hard work. Adding personalized and custom touches makes it all yours, unlike anyone else’s. It also requires great patience with trial and error, potential mistakes, backtracking and repeating steps. Four years of painstaking, creative and very rewarding work. Nearly a year ago I profiled this “Street Legal Race Car”. Well now, it’s built!


Chris Julian finally has completed his Ultima GTR, registered and street legal for maximum fun. Imagine legally driving a car – at least legally from a technical standpoint, if not technique, that would be at home running against true race cars. Running with meaning; just as low, just as quick and almost as light. The Ultima GTR looks similar to the Daytona Prototypes, and it weighs roughly the same, 2300lbs but in this case with a significantly larger motor making more horsepower.

Climbing over the wide sill into the tight, cramped passenger seat takes technique. The fire suppression system interferes with legroom. Don’t disable it accidentally! The 4 point racing harness feels comforting considering how low you sit. The view forward is spectacular, the road looks like it's just in front and right under you with wide bulging front fenders on either side.

Starting up the Corvette Z-06 sourced 427 cubic inch V-8 (LS7) with the headers right behind the passenger compartment announces the fun is going to begin. Even owners of exotics who haven’t assembled anything on their cars all look to see this impossibility roll by. It’s loud, visceral, a little smelly and it’s begging to be run fast. Surprisingly, sitting just 2.75” off the ground at the lowest point still makes for a decent ride on decent roads. The acceleration is fierce, making one laugh out loud and start thinking about only a handful of cars that could accelerate harder on the street. Cornering is flat, period. The limits are far, far too high to explore on the street.

Think about the legendary Cobra. Now lower it, enclose it, add air conditioning, modern brakes, mid-engine layout, fuel injection, modern suspension, minimal weight gain. This is the ultimate modern kit car. It isn’t perfect. It has a minor rattle here, a slight rubbing/clearance problem and a minor tune to optimize the intake and exhaust work the engine has. It was a warm day and despite sitting in traffic and the small cockpit, stayed comfortable inside. It’s well sorted and fantastically fun for home assembly.

Getting it to street legal status takes a few steps. First an application to the DMV, a brake and light inspection by CHP as well as a VIN number assigned and smog for paperwork only. There is no actual smog test nor sound test required. Awesome! The California SPCN/SB100 Street Legal process, although limited to 500 vehicles a year is a process that allows your dream to be licensed for everyday use.

A thorough appraisal was recently done on the car and thanks to the Chris’s talent and innovation; the appraisal by the established Pacific Automobile Appraisers compared the end result to world class one-off concepts from automotive manufacturers and national show winners. I have to concur; it’s nearly a masterpiece thanks to his resources and ability to create special parts.

Many enthusiasts like to assemble and install their own performance parts. Imagine the pride and joy assembling your own car, then improving it like none other of the same model. And then once complete, instead of computer control or interference with the engine power, transmission, suspension, brakes, steering and rear differential, this is a driver’s car, not a car with driver’s “enhancements “ also known as handicaps.

Apr 5, 2017

Porsche Panamera


Three letters in the March 2010 Car & Driver question the 3.3 second 0-60mph time of the Porsche Panamera Turbo that was tested the December 2009 issue. That makes it potentially quicker than many cars with much more power and less weight including the McLaren F1, Ferrari Enzo and Porsche's own GT-2. Weighing 4409lbs with 500hp, on paper it shouldn't beat any of them. There are three reasons it's so quick.

All-wheel drive, the dual clutch transmission and gearing that is probably more aggressive than any performance car in history make it accelerate quicker than much more powerful and lighter cars. The Panamera Twin Turbo is in 3rd THIRD! gear by the time it hits 60mph. Many extreme cars like the Bugatti Veyron, Chevrolet Corvette ZR-1 and others go over 60mph in 1st gear. Check out the Bugatti Veyron road test with the top 10 quickest cars they have tested.

The all-wheel drive ensures no slippage unlike the others where power delivery has to be managed with available traction. I eluded to this challenge in my 60-130mph article. A 1.2 second 0-30mph time is extraordinary, on par with the AWD Veyron and GT-R. I would guess this translates to a 1.6 second 60ft at the dragstrip given the previously mentioned gearing.

The horsepower deficit is apparent in the trap speed in the 119mph range vs. the 125-130mph or higher times of the other cars. With excellent track preparation, technique and usually drag radial tires, a few have been able to match the launch of the Panamera and therefore run a much quicker quarter mile. Modern-day street car drag racing legends such as "Ranger" and "Furman" are examples of Corvette and Viper drivers who have done this.

Finally the 7-speed dual-clutch transmission means nearly uninterrupted power delivery. As one clutch disengages, the next engages with a speed and consistency that can't be humanly repeated. With 5 non-overdrive gears, it's fierce.

There is no other-worldly driving skill excuse or strongly suspect fudging of power levels in any gear with the Porsche Panamera Twin Turbo, unlike the Nissan GT-R. The car doesn't defy physics but it's transmission sure tries to make it seem so. Just wait when the new 911 Twin Turbo is tested.

The 2010 Porsche 911 Twin Turbo assuming the gearing is the same as the Panamera is that it will accelerate even quicker since it's about 800lbs lighter than the Panamera. So besides still not matching the GT-R's "factory" 'Ring time, it still won't accelerate to 130mph 1.6 seconds quicker than production models nor accelerate from 120 to 130mph in .9 seconds either in production form.

A great link for various automotive calculators courtesy of Wallace Racing. There are several for 60ft translations and various speed indicators.

Apr 4, 2017

BMW 318is - Better Mileage With Gearing? Ask Rob About Cars

Hi Rob,
Great articles and photos, thanks so much ,
I have a 1994 BMW 318is. It gets great gas mileage and would love to get even better mileage . The rear end (3rd) member locked up when I first got the car, so I found a deal on a 325 axles and rear end , put it in never changed any gears do you know if the 325 is different than the 318is both were manual transmissions. Should I leave well enough alone ?
Thanks,
FAN

Hello Fan and thank you!
I found this excellent website that lists a LOT of BMW gear ratios, perhaps all of them

It seems that you now have a less-aggressive final drive ratio of 3.15 vs. 3.45. So if you like your mileage and the acceleration is adequate, I would leave it alone and congratulate yourself on a fuel saving modification.

I wouldn't suggest trying anything numerically lower than 3.15 such as the 2.93, even if you can find it. My concern would be inadequate acceleration with the 4-cylinder engine. This would mean using higher revs and consuming more gas, effectively negating your intended result. Also, it may mean using a higher gear for cruising at certain speeds and poor acceleration in 5th gear. If you know anyone that has done it, be sure to write back and share!