Can homebuilt be faster than factory-built? | Factory Five 818 vs. Porsche Boxster S

Tom
By Tom Suddard
Sep 1, 2022 | Factory Five, Porsche, Boxster, comparison, 818 | Posted in Features | From the Feb. 2015 issue | Never miss an article

Photography Credit: Tom Suddard

Many cars have a clear adversary: Mustangs have clashed with Camaros for years. The Evo-versus-STI feud is still going strong. These pairings are more than just petty rivalries, though–they’re an exercise in measuring performance. After all, what’s a race without a well-matched foe nipping at your heels?

But what about a homebuilt roadster made from a wrecked Subaru? Is there a yardstick for the Factory Five 818

We think there is, and it’s called the Porsche Boxster S. Like the 818, the Boxster has a mid-mounted engine with horizontally opposed cylinders. It’s a roadster. It has two seats. And most Boxsters are weekend toys, likely owned by the same kind of enthusiasts who would have the time and ability to build an 818. 

So we set out to compare something built in our garage to a finely engineered German performance car. Did our home-built creation measure up, or did it have room for improvement?

The venue for this test would be The FIRM, a newly renovated motorsports facility just outside of Gainesville, Florida. And the driver wouldn’t be one of us–we wanted a true test pilot for this comparison. We commandeered Dan Shields, five-time SCCA Solo National champion, nationally certified driving instructor, and ASE-certified master technician. He’s also a nice guy. 

If anyone could drive our 818 and keep it in one piece, it would be Dan. As a bonus, he also brought us a Porsche–his wife’s pristine 2002 Boxster S that’s a regular in Porsche Club of America autocross competition. Aside from a set of Bridgestone Potenza RE-11 tires, it’s still stock. Our 818 rolls on Yokohama Advan Neova AD08 R tires, making this a fair fight right down to the rubber.

On paper, there’s only one standout difference between the 818 and the Boxster: weight. The Boxster weighs 1000 pounds more than our homebuilt sports car. 

Time for a friendly face-off. Despite similar layouts, the scales don’t lie: The 818 undercuts the Porsche Boxster by 1000 pounds. 

Otherwise, there’s little difference between the two cars. Once you factor in driveline loss, they both make about the same amount of power. Both cars have a similar footprint, too. 

The question is, will the Boxster’s inherent “Porscheness” make up for its heftiness on track? Or will the 818’s light weight and better suspension design shoot it into the lead?

Track Time

Before we could answer the question, we needed test criteria. After an hour or so of getting acquainted with the 818, Dan mapped out a course. His final design combined a long straight with a series of S-bends, a slalom, a banked sweeper, high-speed transitions, and a few 90-degree, city-style corners. In short, it was the perfect test of a sports car’s abilities: handling, braking, acceleration, transitions and even driver confidence. 

Photography Credit: Tom Suddard

Once he was comfortable driving each car, Dan completed four flying laps of his test course. The verdict? The 818 is faster than the Boxster. 

A thousand pounds is hard to hide on a road course, even when the driver has spent years learning how to work with the extra weight. Dan has campaigned a huge variety of cars–from MG Midget to Ford Mustang–at the national level in both road racing and autocrossing.

Photography Credit: Tom Suddard

Dan’s laps were über-consistent in the Porsche, but varied a fair bit in the 818. We’ll chalk that up to his unfamiliarity with the Factory Five, though we can’t help but wonder if a Porsche is easier to drive than our turbocharged monster.

Creature Comforts

Track testing, though, is only one part of this comparison. That extra 1000 pounds had to go somewhere–Porsche spent it on creature comforts, metal bodywork and safety features. 

Comparing the Boxster and the 818 as street cars isn’t even a contest–one has carpet with sound deadening, one has a metal floor with drain holes. One has a/c, one doesn’t have a roof. One has power windows, one has a hood that constantly waves at the driver like a drunk guy on a parade float. 

The Porsche also has not one trunk, but two. Try to carry anything bigger than an insurance card in the 818, and you’ll be disappointed. If you push through that disappointment and try to put anything in the rear “trunk,” then your cargo will arrive nice and toasty. The Porsche also has crumple zones, air bags, stability control and decades of crash testing experience behind its design. 

Something Else

Good lap times and street manners don’t necessarily add up to a truly great car. It takes something more, something intangible. The 818 and the Boxster both tick the “je ne sais quoi” box, but in very different ways.

The 818 is awesome because of its origin: your own garage. The Porsche, in contrast, hails from a company with a rich racing pedigree and a reputation for producing great sports cars. One lets your neighbors know you’ve finally made it, while the other lets your neighbors know you’ve literally made it.

The Porsche does have the allure of easy maintenance, provided your checkbook is thick enough. Any dealer will gladly work on it, and you’ll never get your hands dirty if you don’t want to. 

The 818, though, is the opposite. No dealer in their right mind would touch it, but its parts are simple and easy to find. Plus, the simple act of buying one means you’re required to learn how to work on it. It’s a safe assumption that anyone with a running 818 has gained the skills to keep it that way. Both cars are well supported by local and national clubs, too.

So what’s the verdict? The 818 is clearly a faster track car, while the Porsche is clearly a better street car. 

Buy the one that fits your desires. If you want a track toy that will remind you of the fun you had playing with Legos as a kid, then buy the 818. If you want a timeless, turnkey sports car that will help you unwind on weekends, buy the Porsche. Either one is a great choice, because either one is a great car. 

At this point, we’re comfortable calling our Factory Five 818 finished. We started with nothing more than a pile of parts, a wrecked Subaru and an instruction manual, and we finished with a car that can attract drooling bystanders, beat a Porsche on track, and take you to work every day. This 10th installment will be the last official story in this project car’s series, but that doesn’t mean it will disappear. We’ll still be writing about it online, so don’t be surprised if you see the occasional update in the pages of Grassroots Motorsports.

Now, what to do with it? As we proved by building a supercar in our garage, almost anything is possible.

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Comments
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dculberson
dculberson PowerDork
10/6/17 2:34 p.m.

1000 pounds and 2 seconds faster on a road course. I would have thought the difference would be more pronounced. What does everyone else think?

tuna55
tuna55 MegaDork
10/6/17 2:44 p.m.

Agreed. That doesn't seem like a big enough difference. Same tire compound? 

Robbie
Robbie GRM+ Memberand PowerDork
10/6/17 2:59 p.m.

Same tire compound I think but Porsche's tires are wider by almost half an inch front and back.

Also, the Porsche has more HP, and more than a few years of sports car engineering prowess behind it.

Edit: doh! I only remembered the second half of the statement that seems plenty contradictory:

"Aside from a set of Bridgestone Potenza RE-11 tires, it’s still stock. Our 818 rolls on Yokohama Advan Neova AD08 R tires, making this a fair fight right down to the rubber."

tuna55
tuna55 MegaDork
10/6/17 3:09 p.m.

In reply to Robbie :

Oops missed that.

 

That makes it pretty disappointing.

 

z31maniac
z31maniac MegaDork
10/6/17 3:32 p.m.

Goes to show weight isn't that important if the car can handle it.

Kreb
Kreb GRM+ Memberand UltraDork
10/6/17 4:07 p.m.

I imagine that someone who isn't as dialed in with the Porsche as Shields might find the performance gap to be greater. 

Vigo
Vigo UltimaDork
10/7/17 7:25 p.m.

I agree, but someone with a lot of experience tracking any MR car has got to be closer than average to hopping into an 818 and doing well. 

I think one thing that's not really mentioned here is that the 818 seems intended to be a thrill machine, and it's a little incongruous to have a mostly stock powertrain in it. Add a little 'easy turbo power' and the gap could become fairly huge, especially on a faster track. Not very easy (or cheap) to add power to the Boxster. 

Brian
Brian MegaDork
10/8/17 6:03 a.m.

Track, 818. Street, Boxter. I say that having visited Factory Five two days ago. 

spin_out
spin_out HalfDork
10/8/17 6:25 a.m.

Danny your car is pretty

irish44j
irish44j UltimaDork
10/8/17 3:10 p.m.

 

If we're tossing out the "living with this car on regular roads" and really just comparing track capability, why not compare the 818 with a track-use Boxster S? From what I've read, a Boxster S stripped down to a "track spec but still street legal" (including a hardtop) gets down to about 2500lbs or less.

Also minor bone to pick that I didn't notice on the first read. For the FF you list the power as 225 (wheel) but list the porsche as 250 (flywheel). This is not apples to apples. 250 at the flywheel is more like 210 at the wheel for the Porsche. So anyone surprised about the "more powerful Porsche" being slower, should look again....  At very least you could have talked to your Porsche tuner buddies (I know you must have one) and found out what a typical "wheel" horsepower for the Boxster is.

Side note: remind me what engine/turbo is in your 818? 

In any case, not defending the Porsche per se, but I'm an analyst so I like to see comparitive analysis conducted using the same criteria and rating. I suspect that a 2500# Boxster S with the same level of "track" modifications as your 818 would probably beat the 818 on the track, or at least come close to it. Just speculation there, of course.

Both will badly thrash my 924S on the track, haha (and my WRX will absolutely annihilate it...)

irish44j
irish44j UltimaDork
10/8/17 3:16 p.m.

A quick internet search indicates that a typical stock early-2000s Boxster S puts down about 220hp and 195 tq to the wheels...

D2W
D2W HalfDork
10/9/17 3:48 p.m.

I've always been a fan of the FFR 818, watching its whole development, but that picture above with the boxster sure makes it look like a cheesy kit car.

Robbie
Robbie GRM+ Memberand PowerDork
10/9/17 4:23 p.m.
D2W said:

I've always been a fan of the FFR 818, watching its whole development, but that picture above with the boxster sure makes it look like a cheesy kit car.

Thank you for putting your finger on exactly how I felt!

Kreb
Kreb GRM+ Memberand UltraDork
10/9/17 4:27 p.m.

The preponderance of graphics on the FF818 doesn't do it any visual favors IMO. The coupe version looks a lot more grown up.

Huckleberry
Huckleberry MegaDork
10/9/17 5:24 p.m.

2.32 second average faster lap is a lifetime in a race.  The 818 would be lapping the Porsche in about 40 or so laps at that track based on those lap times.

Not even close.

irish44j
irish44j UltimaDork
10/9/17 5:44 p.m.

Maybe the next one should be the 818 Coupe vs. Cayman R laugh

nowucme
nowucme New Reader
10/9/17 6:06 p.m.

Is that a 2002 Subaru engine and suspension in the 818? No disrespect to Mr. Smith and the fantastic corral of cars his company builds but it doesn't seem like an apples to apples comparison. Perhaps an Exocet would be a better comp.

Huckleberry
Huckleberry MegaDork
10/9/17 6:26 p.m.
irish44j said:

Maybe the next one should be the 818 Coupe vs. Cayman R laugh

They make an 818R kit for $10,990 that laps Lime Rock in :56 and 2:00 flat at the Glen. So, genuinely for reels fast. If you are going to build a kit car for the track I can't imagine why you wouldn't start with the better spec kit even if you had to mix and match a little to get a license plate. If you are able to swing $20k for a kit car build... you can swing 25k to make it haul ass.  Really you just need two junk cars to be donors... one crappy WRX, and then a 2004-2007 Subaru STI to donate the motor and a few other racy bits.

https://www.factoryfive.com/818/818r/

BA5
BA5 GRM+ Memberand Reader
9/1/22 10:43 a.m.

This is a pretty interesting article.  I'd be curious to hear from the GRM guys who did the test: did you feel like the 818 was appropriately faster than the Porsche given being 1000 lbs lighter?  

I feel like the 2-2.5 sec/lap faster times are right on that edge of "that's an eternity in lap times on a track" and "huh, I thought it'd be faster.  I mean, it's 1000 lbs."

Did you feel like something about the 'home builted-ness' was holding it back?

DaleCarter
DaleCarter GRM+ Memberand New Reader
9/1/22 8:18 p.m.

My answer to the question is "It SHOULD be!"

Building a car without having to comply with liability law, crash standards, provide comfort and luxuries, emissions compliance etc etc makes it REALLY easy to build an extremely quick and well-mannered car.

DaleCarter
DaleCarter GRM+ Memberand New Reader
9/1/22 8:24 p.m.

In reply to dculberson :

Two+ seconds a lap is a LOT of time. At my local tracks, Barber Motorsports Park and Road Atlanta, the driver of the Boxster won't be able to see the FF after 3-4 laps. Put a driver in the FF with as much experience as this driver has in a Boxster/Cayman and watch the gap grow.

Tom Suddard
Tom Suddard GRM+ Memberand Director of Marketing & Digital Assets
9/1/22 9:20 p.m.
BA5 said:

This is a pretty interesting article.  I'd be curious to hear from the GRM guys who did the test: did you feel like the 818 was appropriately faster than the Porsche given being 1000 lbs lighter?  

I feel like the 2-2.5 sec/lap faster times are right on that edge of "that's an eternity in lap times on a track" and "huh, I thought it'd be faster.  I mean, it's 1000 lbs."

Did you feel like something about the 'home builted-ness' was holding it back?

You hit the nail on the head. While our 818 was fun, honestly we never really put the time in to fix some of its inherent evilness. It was a handful.

The Boxster is an amazing, perfectly sorted driving machine. The sort of thing that happens when a bunch of Porsche engineers spend years tuning a chassis. 

The 818 is, well, a kit car. Infinite adjustability and no production car constraints means you can do a lot to improve the driving experience. But it also means you have to do a lot to improve the driving experience, and we focused that project more on the building than the sorting. 

To get an idea of what I'm talking about, check out my article on prepping the 350Z's chassis. This amount of skill/time/effort would have paid dividends with the 818. 

Teh E36 M3
Teh E36 M3 UltraDork
9/1/22 10:56 p.m.

Sounds like it is as much about development as anything else. As tommy said- the booster is the result of really good engineers from a really good company making a really good chassis really shine. None of us- maybe except Keith, or fellas like him who have the skills do really make an imperfect car as near to perfect as possible. 

'Isn't that the fable of the 911? A triumph of development over original engineering? Now make that original engineering nearly perfect....

AnthonyGS (Forum Supporter)
AnthonyGS (Forum Supporter) GRM+ Memberand UltraDork
9/1/22 11:55 p.m.

It actually takes a team of people to build something like the Boxster.  No one person could do it.  A lot of things in life require massive amounts of teamwork to achieve.  It's actually pretty cool when you think about it.  It's also why all project cars are a compromise in ways.  A lot of people have amazing skills far beyond mine and make really cool stuff, but it still takes an entire team to make a Boxster.  Even the FM project cars are the same.  FM had a lot of videos on how they fabbed up the parts for the ND V8 conversion.  It took more than one person to pull that off too.  There was also a lot of integration from work done by teams of people at GM too.  And then there was the team at Mazda that provided the canvass for that automotive art. 

Kreb (Forum Supporter)
Kreb (Forum Supporter) GRM+ Memberand PowerDork
9/2/22 12:40 a.m.
Tom Suddard said:
BA5 said:

This is a pretty interesting article.  I'd be curious to hear from the GRM guys who did the test: did you feel like the 818 was appropriately faster than the Porsche given being 1000 lbs lighter?  

I feel like the 2-2.5 sec/lap faster times are right on that edge of "that's an eternity in lap times on a track" and "huh, I thought it'd be faster.  I mean, it's 1000 lbs."

Did you feel like something about the 'home builted-ness' was holding it back?

You hit the nail on the head. While our 818 was fun, honestly we never really put the time in to fix some of its inherent evilness. It was a handful.

The Boxster is an amazing, perfectly sorted driving machine. The sort of thing that happens when a bunch of Porsche engineers spend years tuning a chassis. 

The 818 is, well, a kit car. Infinite adjustability and no production car constraints means you can do a lot to improve the driving experience. But it also means you have to do a lot to improve the driving experience, and we focused that project more on the building than the sorting. 

To get an idea of what I'm talking about, check out my article on prepping the 350Z's chassis. This amount of skill/time/effort would have paid dividends with the 818. 

That takes me back to a kit car comparo you did a bunch of years ago. Correct me if I'm wrong, but I think that Keith's Locost beat an Ariel Atom and another car that should be faster on paper. The difference was that Keith's car was much more dialed in. It was the beneficiary of development that the other two cars weren't.

All the experienced guys here understand the importance of prep and tuning. I'd bet that a good deal more time could have been extracted from the 818 under the proper care. 

Kreb (Forum Supporter)
Kreb (Forum Supporter) GRM+ Memberand PowerDork
9/2/22 12:42 a.m.

A follow-up with a prepped 818 coupe and perhaps a Cayman S would be very interesting. 

Reply to BA5 and DaleCarter:

If you look at laps 2-5, my Boxster S laps were all about the same, but in the 818 I was getting a lot quicker with each additional lap. Gaining familiarity, exploring the limits. I think the comparison would be more dramatic after four or five more laps.

CrustyRedXpress
CrustyRedXpress GRM+ Memberand HalfDork
9/2/22 11:55 a.m.

"All the experienced guys here understand the importance of prep and tuning. I'd bet that a good deal more time could have been extracted from the 818 under the proper care."

Feels like another win for mundane details, fanatical preparation, and checklists. Competitions (business, sports, dating, etc.) are sometimes won and lost on incredibly small margins and the little stuff compounds. 

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