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Posted by: Aaron Cox Oct 14 2007, 08:58 PM

hmm... lots of people in that boat.

going to later 3.5" struts means, you A ) have to pony up for them B ) use inserts for a heavier 911, or have your 911 units revalved for 914 weight characteristics.

So myself and craig downs sat down and did some thinking.
We wanted to achieve the sleeper look of 15" wheels, but something more modern than M calipers, A calipers, and less expensive than S calipers, AND something you can get parts for (tried getting 951/944 turbo caliper parts lately????)

so we came up with boxsters.... (NON S)
*Fairly Cost effective
*light weight
*pads are double the size
*use readily available 911 carrera rotors
*parts are cheap and available.
*the calipers can be as new as 2003....

So how do you achieve this?

pretty simple. Several mockup sessions behind our favorite mexican food place on lunch breaks.... having the parts... and having a mill.

unlike 3.5" struts, a bolt on solution could not be made to fit under 15" wheels. The 3" ears interfere with the brake pads on the calipers, and spacing them out to clear would require a bigger rotor (951?) and makes 16" wheels mandatory.

Here is what we came up with


The unsuspecting victims.... (fronts and rears.... (rears are going on soon))
Cheap. Light. Newer. Gooder



one of the jigs, ready to put a step into the strut.


making a level 'step' for the adapter to lock into and a nice level/true support.


The finished products, after removing a certain amount of material. Nice and flat and true, lots of surface area


The corresponding step about to be cut into the adapter blocks. 6061 T6 Aluminum.




fast forward a few to the final products




Attached image(s)

Posted by: Dan (Almaden Valley) Oct 14 2007, 09:07 PM

any plans on giving out the specifics..?

or is this going to be something we will be paying for?

Posted by: sixnotfour Oct 14 2007, 09:15 PM

Are those really your shoes?
Nice , patent pending

Posted by: KaptKaos Oct 14 2007, 09:21 PM

For years, we have treated to lovely pictures of Aaron's feet. Mostly in flip flops I might add. So give the boy some props as this is a step up on the evolutionary ladder. Next thing you know, he'll be walking upright.

Oh, nice brakes too!

Posted by: Krieger914 Oct 14 2007, 09:39 PM

Very nice work, but I have to be a shit stirrer. Won't this cause the same problem you have by adding BMW calipers to the stock 4 set-up, that so many people around here argue? BTW I have done the BMW set up and am strongly in favor of this and what I see in this post. Oh and can't you just use Koni adjustable shocks instead of revalving?

Posted by: Aaron Cox Oct 14 2007, 10:08 PM

to answer a few questions...
-914 struts do NOT fit into 3.5" struts to my knowledge. You could use any koni or bilstein or boge designed to fit the later 3.5" housings, BUT they are valved for 911's (heavier). Thus the revalve or???

-Bigger rotor than stock. Its vented and 4mm thicker than standard 911 vented. Should deal with heat fairly well. you can engineer a solution to use larger rotors if you wish (bigger rotor = 16" wheel.)

-specs. That is up to craig downs. He may be up for sharing the engineering, or maybe even mill your struts and blocks for you? In his hands

-shoes. Yes, those are my sexy legs, and beater shoes. OSHA sent me a letter requesting that i use closed toed shoes when working with metal shavings.

Posted by: Aaron Cox Oct 14 2007, 10:10 PM

Wheel fitment:

We have tested the fit of
15x6" DEEP six fuchs
15x7 and 8 Fuchs
15x7 and 8 BBS
15x6 NON deep fuch

They all fit with loads of clearance for wheel weights etc

Posted by: rhodyguy Oct 14 2007, 10:50 PM

are you building a track car?

Posted by: Aaron Cox Oct 14 2007, 10:58 PM

just overkill, and engineering excercises
goin for uber trick street car...

craigs set is done already

Posted by: Travis Neff Oct 14 2007, 10:59 PM

That freakin rocks!

Posted by: rhodyguy Oct 14 2007, 11:00 PM

i see. party on. what does a set of 4 calipers and pads set you back?

k

Posted by: Aaron Cox Oct 14 2007, 11:05 PM

market rate is about 300 per end.

depends on how lucky you get.
i am in 5 calipers around 400 bucks (have an extra rear)
pads are about 20-200 bucks depending on what brand

Posted by: rhodyguy Oct 14 2007, 11:11 PM

cool stuff, but too rich for my blood.

Posted by: jd74914 Oct 14 2007, 11:59 PM

Nice Aaron, I like it.

Will there really be much mechanical advantage over standard M brakes? I mean, they have the same "leverage" on the brake rotors . . .

Besides parts availability, I'm assuming the big advantage of these monoblocks is weight and heat dissipation?


Very cool I want a set

Posted by: Twystd1 Oct 15 2007, 12:14 AM

Awww Hell,

I did the same thing with JB weld and a couple of aluminum prescott seals mixed with spersionate...

And a pocket knife to carve em JUST RIGHT. (Like a Turkey )


Then I crashed the car... Oh well.... Maybe I will try your way......

AA and Craig.... You guys rock.

And your your friggin phone cut out while I was talking to Craig. AGAIN.

OH... And about your carb puddling while idling. Thats a blocked idle jet.

Thats what happens.

AND / OR your floats are high. (Like you on glue...fool)

Good job fellas...!!!! Now where the hell are mine..????

Claytonobitch

Posted by: Brando Oct 15 2007, 04:03 AM

Holy shnap, that shit came out good bro

Maybe Iff'n when I ever have the ability (read: $$$) to go 5-lug I'll invest a few dollars in Craig if he's willing to do a few of these for people...

Posted by: woobn8r Oct 15 2007, 08:50 AM

Nice Job,

They look almost like the Boxter brake set up I bought from Rich....

Posted by: siverson Oct 15 2007, 10:03 AM

Great work!

Posted by: brer Oct 15 2007, 11:17 AM

Nice! but ugly.

Posted by: Brian Mifsud Oct 15 2007, 11:42 AM

so, skipping your feelings about Aaron's legs, what do you think about the calipers?

Nice work Aaron. I like the idea of keeping the 15" wheels..16's are very 80's and anything bigger just looks wrong on the 70's icon the 914 is IHMO..

Posted by: Aaron Cox Oct 15 2007, 12:23 PM

we can finish the edges... these are proof of concept -

'OFF MY BACK MONKEY!' lol.

Posted by: brer Oct 15 2007, 12:35 PM

I'm a crusader for beauty.
Like Everett Ruess, only ruder.

Posted by: Brando Oct 15 2007, 02:25 PM

Uhhh... just noticed. I think you got the wrong caliper side on that strut. Bleeders should be on the top...

Posted by: Dr Evil Oct 15 2007, 09:22 PM

Great, just what I need, something else to want after

Posted by: Aaron Cox Oct 16 2007, 12:14 AM

yes. just mocking it up

craig is gonna chime in here soon with some better pics of the machining process, and whats involved.

these were just rushed 'teaser' pics

Posted by: brer Oct 16 2007, 12:45 AM

I'd like a set of those some day.
maybe we can trade somethin.

Posted by: Brando Oct 16 2007, 07:22 AM

"Teasers" they were indeed!

They're damn hot.

Posted by: thesey914 Oct 16 2007, 08:37 AM

How do the Boxster callipers compare to my 4pot Brembo 964 (3.5" spacing)?

Posted by: BKLA Oct 16 2007, 08:49 AM

Aaron -

Show us the rear (not yours. fool! ) I am interested in how you deal with the retaining pin and it's installation. Drill swing arm? Dimple swing arm? Modify pin and caliper to install from out side?

You're an engineer, right?!?

15 x 7's clear fine on mine! Now with boxsters front AND rear!

Posted by: davesprinkle Oct 16 2007, 09:43 AM

Brake shoes?

Posted by: Aaron Cox Oct 16 2007, 10:34 AM

in which aspect?

cost - about the same
mounting - your 964 calipers are axial mount, while boxsters are radial mount, thus the adapter block.
pad size? boxsters may be a tad bigger. I am not well versed in 964 calipers.
maker - both are brembos
piston sizes - i would have to look them up.

Posted by: craig downs Oct 25 2007, 01:28 AM

I have just finished Aaron's struts and I will share the rest of the procedure.
Here it is mounted to the jig getting ready for locating and drilling of the holes to mount the adaptor.

Posted by: craig downs Oct 25 2007, 01:30 AM

Holes drilled

Posted by: craig downs Oct 25 2007, 01:36 AM

Since the mounting holes are into the step I had to counter bore a pocket so I could
drill the holes

Posted by: craig downs Oct 25 2007, 01:41 AM

Using a transfer punch to mark the mounting holes in the adaptor so they line up
with the holes in the struts.

Posted by: craig downs Oct 25 2007, 01:51 AM

Tapping holes in the struts and checking multiple times with a square to make sure
the threads will be square.


Attached image(s)

Posted by: craig downs Oct 25 2007, 01:54 AM

All for now will add more later

Posted by: Aaron Cox Oct 27 2007, 11:35 PM

Here is a complete pic

Install went great - no surprises
some detailed pics will be posted later




Attached image(s)

Posted by: craig downs Oct 28 2007, 04:07 PM

Here is the rest of the machining
The block drilled and tapped to mount on the strut.



Attached image(s)

Posted by: craig downs Oct 28 2007, 04:14 PM

Oops on the photo above the caliper is centered on the block and the rotor then using a transfer punch to mark the block for the mounting bolts.

Posted by: craig downs Oct 28 2007, 04:17 PM

Getting ready to drill the mounting holes showing the marks made by the transfer
punch.

Posted by: craig downs Oct 28 2007, 04:20 PM

Drilling the holes


Tapping the holes making sure the are square

Posted by: craig downs Oct 28 2007, 04:22 PM

Caliper mounted to the strut

Posted by: craig downs Oct 28 2007, 04:27 PM

Cutting off a little of the old mounting ears so the inboard pad will go all the down
in the caliper.




Attached image(s)

Posted by: craig downs Oct 28 2007, 04:34 PM

Sorry messed up again this is the 1st time I have posted pics so I'm still learning.
Anyway the 2nd photo above the caliper is mounted with the pads and is ready to go.


Here is another one

Posted by: craig downs Oct 28 2007, 04:37 PM

Here it is installed in the car

Posted by: Aaron Cox Oct 29 2007, 12:49 PM

waiting on a tie rod end, and a pair of bolts - and then i will report how well these babies stop.

The total piston area of these is right about the same as a pair of A calipers (around 5% smaller actually), so there is no need to change the master cylinder to anything larger than a 19mm

Posted by: andys Oct 29 2007, 12:54 PM

What is the pad area compared to the A calipers?

Thanks,

Andys

Posted by: Aaron Cox Oct 29 2007, 01:05 PM

between 1 and 2x as big

i dont actually know, i would guesstimate a bit under 2x as big.

Posted by: john rogers Oct 29 2007, 01:32 PM

Would it be possible to not mill the strut mount where you do to get the edge to locate the adapter block and instead use the edge where you cut off the extra material as a locator? I would be interested to try this setup on the vintage 2.0L race car as I have a set of the 4 bolt hubs with vented rotors and a bit of additional brake ability is always nice. This would be a good real racing stress test I would think.

Posted by: Aaron Cox Oct 29 2007, 03:48 PM

we havent looked at a 4cyl strut....

the ears must be cut to clear the pads

Posted by: Aaron Cox Oct 29 2007, 05:32 PM

here are more facts about the swap of calipers vs A calipers.

http://members.rennlist.com/sjanes/brakes.htm

Posted by: Brando Oct 30 2007, 01:31 PM

What do Boxster calipers usually run for a set of 4?

Also, when do we see pics for how you're modifiying the rear trailing arms to mount these?

Posted by: Aaron Cox Oct 30 2007, 04:15 PM

rich johnson makes a simple bolt on adapter for the rear.
You can also mill some yourself if you are so inclined.

Boxster calipers usually run about 300 per axle... give or take.... on ebay.

Posted by: neo914-6 Oct 30 2007, 05:24 PM

Rich's fine work:



He repainted the calipers for me.

Posted by: Brando Oct 30 2007, 06:08 PM

What stopped you from using Boxster S calipers? Size? Cost?

Posted by: neo914-6 Oct 30 2007, 06:38 PM

If you're refering to my earlier plans, they would have fit in my 18's and I already had a pair. I didn't want to focus my time on prototyping them and Rich has proven adapters so I sold them.

If you're refering to use with 15", they are larger and less available so yes size and cost are a factor.

Posted by: TeenerTim Jan 11 2008, 08:36 AM

How about an update?
Any idea of cost?
Would it be possible/easier to modify an existing 3.5" adapter to work on a 3" strut?

Posted by: Aaron Cox Jan 11 2008, 03:27 PM

They stop on a dime and give ya change

cost? market rate on a PAIR of calipers is around 300 bucks
Machining time? Ask craig.... a few sixpacks and lots of time on the bridegport.

You cannot use a bolt on adapter, ad the ears of the strut interfere with the pad. THUS the ears were trimmed as you saw.

I am sure you could use a way bigger rotor, and make a bolt on adapter, requiring 16" wheels or larger. Try a 944 turbo rotor for that.

Posted by: So.Cal.914 Jan 11 2008, 03:34 PM

Nice Aaron.

Posted by: spunone Jan 11 2008, 07:29 PM

WOW Aaron had shoes on ......

Posted by: craig downs Jan 11 2008, 07:40 PM

Boy do they work. We got them mounted and went for a spin. Got down the street
a little bit and Aaron gave them a firm petal and holy sh*t they are powerful with no
lock up. This was with the stock rear calipers. I can imagine how it will be with the
boxster rear calipers installed.
Here is the rear mocked up. Just have to install a 911 e-brake 1st

Posted by: craig downs Jan 11 2008, 07:48 PM

Oh the rears are a lot easier. They just require a aluminium adaptor that bolts
to the stock mounts

Posted by: McMark Jan 11 2008, 07:52 PM

Cool, cool, cool!

Posted by: TVRLOTUSTR3 Jan 12 2008, 12:59 PM

The brake line fittings on the caliper (Banjo) are they stock boxster? I need a set for a 993 brake conversion for my rear calipers. It is tight between the caliper and trailing arm. Those would be exactly what I need instead of trying to make a tight bend with a steel brake line.

Thanks! great thread

Posted by: craig downs Jan 12 2008, 02:48 PM

The banjo fitting is from a 911 M caliper

Posted by: TVRLOTUSTR3 Jan 12 2008, 06:13 PM

I have several sets 0f 911 M calipers, two 911 front suspension setups and none have banjo fitings.

Thanks,
Ken

Posted by: TVRLOTUSTR3 Jan 12 2008, 06:30 PM

I take it all back, I have A calipers 3.5". I always get them confused.

Thanks,
Ken

Posted by: daveyboybadion Jan 17 2008, 03:43 AM

So did you guys just post these on Ebay for sale?...daveyboy

Posted by: Aaron Cox Jan 17 2008, 11:03 AM

nope..... alot of work.
with these pictures, and a set of boxster calipers + a mill- someone could recreate these pretty easily. Just takes some time. I'm sure we could even supply some dimensions if someone wanted to make some.


there are adapters out there already for putting them on 3.5" struts..... just not 3" struts.