If you are willing to use 6" or 7" x 16" Fuchs the tires below are very close to the original diameter at 24.8" and I bet will give good performance too:

https://www.tirerack.com/tires/tires.jsp?ti...0&tab=Sizes

Saw that, and had same thought. My 914 did the same thing to its inner fenders with 205/60R15 Yokohama A-008R TU R-compound "balloons" back in the 1990s, but less aggressively. Had too much negative camber, something I fixed shortly thereafter. Never had inner fender issues again.

With the camber within spec, the first point of contact for a 215/60 on a 15x7R is the brake line on trailing arm. Relocating the line is easy enough; getting a bit more space there for a 215 is the trick. A 225 would presumably need that much more space at the arm, and would love the option to run either.



Very cool that the A-008P (with P being for Porsche) is available again, but want to stay on 15s.

Hoping Yokohama might add 225/50R16 for 911 fitments, and then the 195/65R15 & 215/60R15 A-008P that was long available. Had a set of 205/60R15 A-008R TUs and some of the very last 195/65R15 A-008P. Both were great for the street—so long as it was dry out.

Car on the A-008P from years ago seen below, on the day after Rennsport Reunion IV, I think—so 2011. My my, time flies…

Love those tires
Hoping they come back with 255/50/16's

July 2007 WCR
Click to view attachment

Fuch it and go 17s with a deep six lip look..This Kid likes em..
rub marks are from 7x15 Fuchs, 205x15

That's 2" over the line.......my favorite T shirt

Lol!

Rory, the principled man.

My snark comes from experience

Your 215/60-15 are the only tires I call balloons. I even have a 225/60 but that pic might get you too excited

A few more pics and I'll post why.

I agree that the market is very different today from what it was in the 80s and 90s. Back then, the only thing that mattered to most 914 owners was the price. If it wasn't cheap, they weren't buying it. Now, quite a few 914s are in the hands of people who are much more willing to spend money on them.

I don't know what kind of market there would be for aftermarket trailing arms, though. Might be an interesting project for someone, but I suspect that not enough people have run into problems with the 50-year-old steel parts to make that much of one, but my crystal ball doesn't work for crap! (I was absolutely certain that the Cayenne would never sell, for one thing.)

They would be neat, but they might wind up a one-off kind of thing.

--DD

Ha, 225/60 just a bit too F-150.

215/60 no more "ballooney" than 185/70 or 195/65—matched O.D./sidewall height and was standard on the rear of RS 2.7, RS 3.0, early 930, SC, 3.2, etc. Also look pretty fantastic on the back of a 914…

The wheel /tire combo most sixes actually left the factory with. A rare sight now.

well 7.5 x 16s ..No flares,, If you have flares 245/50 x15 on 9s

Mmmmmmmm....the Jon Lowe GT

^ Fully agreed.




I don't, either, and not sure anyone does.

But looking at my options—rebuild another set of 50yo steel trailing arms for $1000-2400 for a bunch of custom work that others have done, too—got me to thinking there must be a better way.

Carbon-fiber/titanium/Elephant Racing NASA spring plate/etc are overkill. Steel seems like a better idea, and Rennline's pair of height-adjust spring plates for the 911 for $250 (!) seem more down the right road. "Simply" lenghten, triangulate, and add way to mount 986 carrier with caliper ears & e-brake and it might be something pretty attractive—for any 914 owner who puts performance ahead of originality.

Goals:

• At least as strong as factory arms
• Sacrificial to protect the unibody in event of an impact?
• Option to replicate or exceed strength of reinforced arms?
• Two lower mounting points for dampers for lowered cars?
• Fine ride-height adjust for corner balancing?
• Fine adjust for toe and/or camber?
• Save weight if possible while keeping price below cost of rebuilt/modified arms
• Provide more room for 215 or 225 tire on 15x7R wheel or custom (or 951) 16x7s

Not sure steel arms would save much weight, but alloy 986 carriers and alloy calipers might. Engineering the arm is way above my pay grade. Needs someone who understands the 914 suspension geometry well, torsional loads, etc.

I wonder how many 914-6s are still running 110hp to preserve the 911's place in the lineup—or U.S. ride height and 165R15s, for that matter!

They've got to be few and far between.



Love a narrow 914 with its fenders stuffed full of tire…and a GT/M471 car done right. Both of these sure qualify…

Boxster carriers with 15x7 BBS wheels...they almost[i] fit. I am sure with 16" and larger no problem.

Click to view attachment

Clearance with my 23.3mm(?) offset BBS wheels with 205/55-15s
I had borrowed a fixture to with the intent to modify the trailing arm by moving the tire mounting face inboard 1". I am glad I did not perform this as now the inside of the wheel/tire would for sure hit the inboard trunk wall.


Click to view attachment

^ Thank you for this, Mike!

Real-world test fit just as I learned something I never knew: 15-inch wheels were actually considered as standard equipment for the cost-cutting 986 but finally ruled out because they looked way too small no matter how cheap they were.

From your pic, it looks like the caliper is an issue, and maybe the 986 "pinch" strut mount too? Was thinking the latter was going to have to be modified or removed, but interesting to see the rear caliper that tight to the wheel—as 986 2.5 calipers fit inside of a 15-inch Fuchs with various custom mounts out there. If the caliper is positioned as on a stock 914 or 986, the e-brake cable is going the right way and might even be set up to hook right up with a 914. "Steering" knuckle at the back could be used for mounting to a steel arm and/or for fine toe adjustment.

Will see if I can figure out how far I spaced the 15x7R Fuchs when I test-fit the 215/60, as that may help with clearance. It was a fair bit.

EDIT: Just noticed the 987 part number. If I remember right, PAG beefed up the Brembo castings for the 986 to incorporate larger rear wheel bearings around the same time or just after the 3.2-liter Boxster S came out (1999 for 2000 MY). I wonder if that would have had any effect on the castings' outer dimensions? In this case, it might matter…

Too much bad weather last week but did score a Boxster susp yesterday

I'll post up my findings as I get to play with it.

Sweet.
Still rocking the 80s 2-door Pathfinder.

Ignore this... wrong axle

Ah, thanks for reporting back!

Hopes dashed with #3 for those who want to stick with 15s, as a fairly thick spacer is a given with 911R (or similar) rear wheels. So what allows use of 986 calipers with 15s on a 914 trailing arm? Smaller rotor diameter/closer mounting? as a fairly thick spacer is a given with 911R (or similar) rear wheels.

I’ve put lots of 15’s on cars with Boxster calipers. SirAndy has Boxster calipers f&r with 15x7 cookies.

They have to be regular Boxster calipers and not Boxster S calipers.

Custom 15s do fit on the 5 speed 2.7 986s and earlier. Carl V down in San Diego ran them back in the 'Oughties.

(Wasn't a custom wheel part of the plan?)

914-6 brakes

DISC SIZE FRONT 11.12 in/282 mm
DISC SIZE REAR 11.26 in/286 mm

986 brakes

DISC SIZE FRONT 11.73 in/298 mm x 0.94 in/24 mm (vented)
DISC SIZE REAR 11.50 in/292 mm x .79 in/20 mm (vented)

A quarter inch can be a pesky thing…

Yeah, potentially—but a custom wheel being:

> 15x7R (factory 911R wheel but $$$$)
> Weidman 15x7R (modified deep 6, attainable)
> Group 4 15x7R ($550 new)

Question is how much spacer, and even then if it would work. Guessing what is a tight fit with a 911/914-sized rotor and may be a no-go with a 986 rotor.

You use Carrera rotors for the Boxster caliper conversions.

^ Yes, and now looking at the 986 rotor sizes I can see why VCI (and others) question 986 caliper upgrades for not dealing with the heat-sink element in the way a 930 setup does—though a 930 setup is a very expensive proposition these days and I suspect 986 calipers are hard to beat for weight, stiffness, cost, and pad pressure spread across four pistons instead of two.

I ran 930 brakes before i switched to the Boxster calipers. The 930 brakes never worked as well as they should, the Boxster brakes are *much* better.

Btw. i had to machine the RJ adapters slightly to use the vented rotors i had, which are slightly wider and the calipers otherwise would not be centered over the rotors.


PS: I still have the 930 calipers in a box somewhere, if anyone wants a set

Tuthill has some interesting calipers and probably could advise on adaptation to a 914 trailing arm.


https://www.tuthillporsche.com/product/tuth...ke-caliper-set/

Click to view attachment

The 930 is a heavy car. I think they are really close to 3K so I could see the need for big brakes at the track. The Boxster brakes and Carrera rotors are total overkill for our cars. Not that I have a problem with it.

Porsche put S front and M rear calipers on the early turbos.

Steel bolts in aluminum parts equals stupid 4 hour disassemble times.

GOOD NEWS!!!!

15" fake Fuchs fit the stock rear by a pinky tip. Important to know that the thickness of the spacer is also the caliper to spoke clearance. No spacer = scratched caliper.





Weight whole ~ 25.5 lbs. Weight with the mount on the ground ~ 23 lbs.





More to come

Yep, there are a lot of cars out there with 986 calipers under 15s—so we know they'll work up front with 911 rotors. The question is whether 15s will go over a 986 rear rotor that's 0.25~ inch larger in diameter and a caliper that's presumably moved out similarly.

Looks like it might.

Chris, I wish I had measured how many washers I put in there during the test fit (will scrounge around to see if I did), but it seems that 10mm to 22mm spacers are commonly used to take advantage of the 911R's offset to get a lot of tire into narrow-body 911s and 914s. So if it's only scratching the caliper without a spacer, that might be fine. Wish I lived closer to stop by with a 15x6 "deep six," and that I still had a loose 911R 15x7 or two. Aftermarket 15s are a whole other kettle of fish.

Nonetheless, very interesting, and that many parts bolted to the carrier comes up lighter than I would have expected…

Really.. "Total Overkill"....

I have Boxster brakes and they are not big enough for my car.

Hey 4.0/Vonnen man—you're just in time to do some dreaming. Cuz' if we're gonna do some dreaming…

The hot setup would be ceramic-composite rotors that work with 986 calipers. Suspect they would not only be enough for higher-power cars, but would also delete a huge amount of unsprung weight and…90-95% of the brake dust too. Downside is the usual one, though it's a lot less than the $20-30k+ seen with a set of PCCB rotors after the fact. And once you've tried PCCB, it's hard to go back. Initial bite is fabulous, and say goodbye to fade forever. Poking around, it looks like there's a vendor who can supply them for $6-8k a set depending on the size of the order. I believe they're unlike PCCB in that they aren't a mere skin—so they can be redone. If they ever need to be…

Other downside is they may need to be closer to 11.75~ inches in diameter. Their smallest diameter currently is 12 inches or just under. Questions around how much smaller they can get did come up, and it's gonna to matter with 15s.

Otherwise, you probably need 930 brakes for that 4.0. And they be heavy and costly too. Now add the cost of replacement rotors and pads from time to time…

I have 991 C4S calipers for the fronts that were rebuilt by PMB. I am moving the front Boxster calipers to the rear, after they get rebuilt and powedercoated to match the fronts. I have not installed the fronts yet. Still looking for the right pads.

Guessing 16s…at least?

What rotors?

I mildly despise some of Porsche's more recent calipers, as many of them require caliper removal for pad changes. I get the argument for stiffer calipers, but when customers are creating stud kits to avoid damaging aluminum threads in the uprights during regular pad changes with track use, I have to question the logic. Fine (ish) for a street car, not so fine for a track day car.

Your 4.0-liter aside (!), I have to think 986 2.5 calipers front and rear on old-fashioned Carrera rotors are an excellent setup for the majority of hot rod 914s. Light, modern, and more than sufficient to slow 2,900-3,200+ Boxsters with 200-225+ hp on back roads where I pounded them again and again without running into fade. They held up where a 385-hp 996 GT3 on iron rotors eventually began to get pretty smelly—a precursor to fade. Two 996 GT2s with 456 hp, far more torque, and PCCB didn't bat an eye.

I'd really like to know if a 17x7 ET23 would fit on a narrow body?

This guy on the bird has a GB coming up on Maxilite fuchs that are the nicest repops I've seen.

http://forums.pelicanparts.com/porsche-911...s-replicas.html

http://www.914world.com/bbs2/index.php?showtopic=170890

As mentioned above, i had to machine the RJ adapters to center the calipers over the 24mm Carrera vented rotors. That's plenty of rotor to stop a 914.

^ Fully agree.

(Unless it's got something truly wild in the engine bay. Like a twin-turbo V8. )

HP has no bearing on braking. Only mass and velocity.

Horsepower/torque has a big bearing on velocity…



I've learned this over and over in testing. A prime example was the 991.2 Carrera line cars, which left each corner and arrived at the next a whole lot faster than their NA predecessors. Brake fade was an obvious weak point on a closed rally stage at the press launch in Tenerife.

Agreed.. but extreme power to weight ratios can result in an extremely high velocity in a short period of time. So bigger brakes are a requirement to shed that aforementioned velocity in an equally short time.

Brakes are a function of weight, not HP. People upgrade brakes with HP because they tend to drive more aggressive and push the fade limits or have stickier tires that can handle the forces.
Basically, match the brakes to the weight + tires + driver.

A narrow body 914 doesn't need Box calipers, but they are an improvement in so many other ways that it makes sense.

^ This. And very well stated.

Reached out to an engineer with an impressive CV and a deep working knowledge of the 914 re: engineering a trailing arm that could link a 986 carrier to the 914's pickup point.

The 986 carrier idea may ultimately be compatible with 16-inch wheels and above (which makes it useless to me), but I'm curious to see what he says.

But HP has a little something to do with what velocity your car will attain . So I'd argue more hp can use more brakes.

...

Unsurprisingly, the engineer I checked with said modding a pair of 914 trailing arms made more sense than engineering > tooling > manufacturing new arms. Which is, of course, is 1,000% correct based on the economics of a one-off project.

I still think there's a (small) market for a better solution for the 914, given:

1) The number of improved spring plate options available for 911s (yes, a lot more cars, but I doubt any of the offerings are made in four-figure batches, as the % of 911 owners interested in tossing their stock arms probably isn't huge. Also, consider the production numbers: Porsche built its 1,000,000th 911 in 2017, but a lot of those 911s are water-cooled; now consider that 115,000+ 914s were built over seven years).

2) Eric Shea's ultimate five-lug conversion thread—which really should be a Classic—has 63,000 views since 2010 while this thread has 5,000+ views since…January 26 (even if one accounts for the peanut gallery/trainwreck aspect)

It is and has been for many years

Ah, apologies.

Stock rear fender and why some tires don't fit well. Just over 9" of total tire space.

Driver side:




Pass side: