Front suspension measurement for possible swap

67dubcab · 01-18-2015, 09:23 PM

I am researching front suspension possibilities for my 67 V.W. double cab truck (bus).
Since I am already running a 3.2 911 engine and the rear suspension and trans-axle from a 944 I figure I could use some 928 content!
What I would like to know is the distance from the front A-arm mounting point to the wheel mounting face. I have been doing some searches here and note that there is some changes from the early to the late cars. Ideally I would like to get a measurement for both.
So if any of you kind shark owners have a car with the front wheel off and could put a straight edge on the rotor face and tape back to the A-arm mounting point that would be awesome.
For context here is the possible recipient.

Thanks in advance.

Danglerb · 01-19-2015, 08:55 PM

Any picts with the wheel off of the VW suspension?

928 78/86 and 87+ have different geometry.

67dubcab · 01-19-2015, 10:16 PM

Here are some shots of the existing suspension, it is a 4" narrowed (originally intended for early offset wheels) ball joint (later bus) welded 2.5" drop 944 s2 spindles, 944 s2 Brembos/custom Bilstien coil-overs #220 springs.
My aim is to junk all this (except the coil overs) and fab a new suspension.
What I would like to know is the overall dim. of the 928 suspension from the upper A-arm mounting point on the body to the wheel mounting surface, the measurement need not be precise, just good enough to rough out the needed room.
And yes, the difference between early and late would great.

Mrmerlin · 01-20-2015, 05:07 PM

the bus chassis has a very compact suspension,
the 928 will require about 2 feet of clearance for the shock assembly,
and dont forget the A arms must also be anchored to the chassis.

Very nice Vdub

67dubcab · 01-20-2015, 09:21 PM

Hey Mrmerlin,
Thanks for the kind remark.
I have planned from the start of this project to build a new front suspension and after driving this rig for about a year and a half and around 8-10 thousand miles I am ready to figure it out.
My basic plan was to work with my fabricator and design a custom upper and lower a-arm suspension using my present hybrid spindles and coil-overs with a 911 rack&pinion.
I am always trying to keep most of the build stock Porsche so thats where the 928 front end comes in. I am not interested in doing a strut front suspension so that shortens the list.
I do not plan to use the stock 928 coil over so height should not be a issue.

Mrmerlin · 01-21-2015, 12:33 PM

I wonder if you could incorporate a 911 front end using torsion bars.
The 928 lower control arms come from a Tiger tank LOL.
The flat wheels were lifted from the bogey wheels.

67dubcab · 01-21-2015, 10:44 PM

Hey Mrmerlin,
For sure not going 911 on the front end, not a fan of strut suspensions.
My double cab is approaching tank weight status at #3100 with me in it, and a 54% front weight bias so tank parts are needed. I also often load it to #4500 gross and have a trailer hitch which I went over #6000 on a dump run with the bed and trailer loaded-it drove fine.
It is a working truck-just trying to make it work faster!

No one still have a 928 with a front wheel off to tape out the overall a-arm frame mount to wheel mount surface?

Danglerb · 01-22-2015, 07:03 PM

A arms are pretty straight forward, is there some reason not to just fabricate something that fits?

Here are lots of picts.
Hello All,

67dubcab · 01-22-2015, 11:12 PM

Hey Danglerb, thanks for the link.
I am confident my fabricator and I could design and build a fully custom A-arm front end but that would be much more involved than modifying a existing set-up.
We would still need a rear steer spindle that would have the Porsche wheel pattern and run 4 piston Brembo's so would probably start with a 928 parts anyway.
My whole build philosophy so far has been to use stock(isn) Porsche parts and make the fabrication needed to install them-mostly working so far.
If it looks like the 928 front end is a good choice then I just need to match the stock mounting points to maintain original Porsche design parameters.
I realize that Porsche did not foresee these parts installed in a 3.2 powered mid-engine split window double cab but I think those engineers would at least chuckle if not raise a beer to the effort.
If I get the base measurement and decide to move forward with the project I promise I will purchase the parts legit and not sawmill them out of a running/restorable car.

honerboys · honerboys's Garage

this the measurement you need - it's a shade over 15 3/4 inches - this car is an 84s

honerboys · honerboys's Garage

well since you got my lazy butt outside anyway I measured an assembly I have on the side of the house - this one is from a 79 - hard to set it just like it is on the car but the measurement was right around 16 inches give or take - might be the same as the 84? - others on here would know better than me - good luck

67dubcab · 01-23-2015, 11:42 PM

Thanks honerboys!
That is the dimension I am looking for, and you verified it with two samples!
The present suspension in the D.C. has about 15-1/4" mounting face to frame with7" et55 wheels so it is close, but I could pocket the frame to mount the upper arm farther inboard to allow for spacers to adjust camber or to run a 8" wheel and a 245 front tire which is about as wide as I think I would like.
Looking like it is do-able, just need to determine if the 928 front suspension is the one to roll with.
Any one with a S4 they can measure for comparison?