TheSamba.com :: View topic - Porsche Powered Mid-Engine Double Cab Build

Mon Jan 25, 2010 12:23 am

Hello,
long time Samba lurker, first time thread starter.
Here is a bit(alot) of background as to how I got to the point in the subject title.
I purchased my 67 double cab about eight years ago from a Samba add and flew up to Seattle then drove it home to Norcal that night.
It had a mild 2110 , stock suspension ,modified transaxle with higher gear ratios and stock R.G.B's.
It had all the typical rust issues but was solid overall and ran o.k.
The truck is my daily driver shop truck and served me well for about 15,000 miles till the "bullit-proof" engine caught a slug and snapped its forged crank in half.
I ran it for another 5000 miles with a stock single port engine from my 69 ghia convertible (a little slow but a great engine).
The next issue was the front spindle was destroyed by a frozen bearing.
Time to I.R.S it!
I went with a Wagenswest 4" narrowed/ball joint /welded 944 drop spindle/adjustable beam and his i.r.s.kit.
I found a early(pre 85.5) 944 parts car for the front spindles,rear steel arms,driveshafts,complete brakes and master cylinder,leather seats.
I picked up a cheap superbeetle transaxle(single-side cover,3.88 r.p.) and replaced the output flanges with a thing(181) flanges and the 944 axles bolt right up.
This set-up requires no welding and no cutting for excellent braking and good handling, good range of height adjustability (almost stock to almost slammed).
I ran a used 1835 dual kadron engine to get it back on the road while I waited for my built transaxle and collected parts to build a type 4 engine.
The transaxle never came, and never will. Another Churning Gear victim.
Time to re-assess the situation.
The type 4 build is not cheap and is really trying to be reliable, powerful, stock mannered engine-kinda like a Porsche 911 motor!
Round about this time the hyper, loud and fun 1835 develops a terminal crack in the case, yay magnesium!
So, the idea I had while pulling parts off the 944 about using the 944 transaxle with a shortened torque tube to a mid-mounted engine under the seat pedestal seemed like the next logical step. javascript:emoticon(':shock:')

Mon Jan 25, 2010 12:46 am

Pictures. This will be awesome. Is it going to be made for handling? Some fancy front suspension in store? 8)

Mon Jan 25, 2010 4:55 pm

Mini me-chanic pointing out the difference between a block and a jackstand.

Getting some work done between naps.

As long as 944 owners forget to replace the timing belt there will always be a fresh supply of brake and suspension parts.

Mon Jan 25, 2010 6:45 pm

Above are some shots before the Wagenswest front beam and I.R.S. kit was installed. The beam fit perfectly, the only thing I would change would be to go 2" narrowed instead of 4", as I ended up going to Porsche late offset rims which are mostly 50+ et causing too much front "tuck"(good if you are going for that look,bad if you want it to handle well)
To get the track back I am currently using 1.5" spacers- aluminum but still heavy (current front wheels are et 55 16-7.
For the back wheels the more offset the better.

Off to the fabricator for the first visit, towed by my stand-in daily driver(keeps me focused on the build).

Mon Jan 25, 2010 10:50 pm

The build goals for double cab:
Daily driver status=reliable
Shop truck=gotta haul stuff(at least 1000#)
Gotta haul kids
Stop waving farm tractors to pass=230+ h.p. probably enough
Good mileage=20+ m.p.g.
Fuel injection=above and reduced emissions(dual cats)
Gotta stop=4 piston brembos should be overly sufficient
Handle better than the above overtaking tractors
Safer (relatively)=shoulder belts front and back/full cage/headrests

The basic build specs:
84 Porsche 911 3.2 engine
90 944s2 transaxle
90 944s2 front spindles/complete rear suspension including torsion tube
complete 4piston Brembo brakes from the 944s2 (turbo spec.)
86 944 aluminum rear arms to reduce track
4 wheel coil-over shocks to increase spring rates

I spent a year researching to make a plan and parts list then gathering the specific parts. The Samba, craigslist, and Pelican Parts were excellent resources, even ebay came in handy(mostly to find out what not to pay for a part)

The missing part to my master plan was someone to weld and fabricate this beast,
something I am ill prepared to do.
While surfing for welding and fabricating I found "Offroad Fabrication Network"
I saw some posts of awesome ability from one calling himself "Twisted Minis" he also was located in Windsor C.A. a township close to me. I had found my man.
Upon our meeting I was surprised at his youthful appearance and generous stature, I was expecting a grizzled old master. He agreed to assist in my mad plan and the build was on!

The hired metal-slinger Seth. Don't hate him for cutting a double cab, hate him for his mad skillz("hey Seth, its the Discovery channel on line one")

Some aircooled motovation

Mon Jan 25, 2010 11:16 pm

I can't wait to see this thing finished, its gonna scream! Do you have a build thread on this going on another forum? It sure looks familiar.

Tue Jan 26, 2010 10:35 am

There is a thread on Seth's site and Offroad Fabrication Network, and briefly on the Samba a link to Seth's site.

The first thing I had Seth do was cut and rotate the aluminum intake manifold to lower the engine profile and rotate the exhaust flanges on the Porsche 993 heat exchangers.

Tue Jan 26, 2010 1:42 pm

That is going to be bad ass!

Tue Jan 26, 2010 2:01 pm

...watching
Keep going !

Tue Jan 26, 2010 2:02 pm

67dubcab wrote: a mid-mounted engine under the seat pedestal seemed like the next logical step. (':shock:')

I'm glad it's not a logical step for most.

It's your ride, do what you like. I'm interested in seeing it evolve.

Tue Jan 26, 2010 6:17 pm

Oh, I have admired the "Twisted Minis" TIG welds on another thread. Very nice work. This project has potential!!

Tue Jan 26, 2010 7:21 pm

Seth is the young master,very talented and creative.
He has his own business at a age where most guys would still be sweeping the shop floor. He has more photos than I and will probably start posting up soon.
Here are some shots of the 944 rear suspension.

Tue Jan 26, 2010 8:54 pm

wow :shock:

Wed Jan 27, 2010 12:35 am

Okay I think I understand that I am allowed to post all of my pictures now starting with the axle swap, so here we go. I have about 100 pictures to post so give me some time in between posts, this could take a while.

First shot is the stock torsion tube that needs to be removed. Second shot is the Porsche 944 torsion tube with most of the stock tabs cleaned off. Third shot is the stock tube removed. I cut as closely to the tube as possible, but not much was left.

Some shots of the arms on and the tube fully welded.

Wed Jan 27, 2010 12:49 am

Stephen brought me some blue prints for a big square thing. I wasn't entirely sure what I was building at this point really, but later came to realize Stephen did a really good job designing all the parts I built from his blue prints. His drawings where also some of the best I have gotten to work from, I get a lot of napkin drawings, or just a picture of something and "build this."

Then there was the bell housing. Again I wasn't entirely sure what was going on here, I just weld stuff. He brought in the housing pre cut, and a piece of thick 6061 angle trimmed to fit it. I welded it together after some extensive cleaning of the housing.

He took it back to his machinist at this point and had it milled down to match the flange and a hole cut for the shaft. I used the piece in the center to index the 944 section that bolts to the torque tube.

Later he brought the sub frame back and had some motor mount drawings. He had seen some dimpled holes I used on something else and liked them. And as always "stronger, lighter, faster" is the goal. So I built the mounts out of 1/8" cold rolled 1018 plate with a 2.5" and 2" dimpled hole, and the top plates are 3/16" for both the front and rear mounts.

Here is the mock up on the mounts, measuring and figuring still.

TIG welded and added a flange for some rigidity.

Then pasted onto the subframe.

It wasn't until later when I first saw the motor that all this stuff clicked in my head and started to make sense as to what I was building.

Wed Jan 27, 2010 12:59 am

I modified an RCI fuel cell for him to fit over the tunnel I made to fit over the torque tube (forgot to take pictures of that part though). I also added a filler neck to the side of the tank that will line up with stock gas door. I made it out of 2" .120 wall 6061 T6 tube and cut a 30 degree angle on the end to make it easier to get the fuel hose onto, and so that it looks cleaner.

Here are some shots of the cage I'm working on for it. It's not built to any organizations specs, it's just built to do what Stephen wants without interfering with passenger room too much. It really stiffened the body/chassis up and it is only done in the B and C pillar right now. It will go all the way forward once it is complete.

This was a pain.

Wed Jan 27, 2010 1:19 am

Here are some pictures from the day we installed the motor. It goes in from the bottom, which is pretty fun.

Rotated intake.

In the last shot you can see an addition to the cage I made in the morning before putting the motor in (no more welding inside after the motor goes in). I felt like the C pillar needed some extra help with no X or any bars continuing to the rear of the vehicle from the top. I like how it turned out with the dimples, lets me use thinner plate and keep the weight down.

Here it is on stands in the shop.

Here are some pictures of the trans axle mount.

Wed Jan 27, 2010 1:24 am

lovin' it

Wed Jan 27, 2010 1:28 am

Here are some bell cranks I built for the rear suspension.

Here I am starting to work on the mount for the bell crank.

Here is a piece of the tab that will capture the bell crank in double shear. I decided to keep with the double plated bolt holes I started on the bell crank on all the tabs back here. You can also see below it, a custom spacer I machined for the coilovers since they are not a standard size.

The setup is almost done here. I still need to do some clean up when it comes back, like capping off the open ends of the tube, and patching the floor back in all the way and sealing it up.

Wed Jan 27, 2010 1:38 am

Next I machined some links out of solid 6061 T6 aluminum.

Here are some custom bolts I made to put coilovers on the narrowed beam. The bearing on the coilovers the Stephen got have an oddball bearing, that measures .588" (I made custom spacers to go from this size to a 1/2" bolt for the rear and lower front mount). So instead of running a bolt with a spacer on it, I figured I would make something a little stronger that looks a little cleaner. The bolt itself is 4130 chromoly, all corners lightly radiused to prevent any stress risers, and the suspension load is transferred entirely into the chromoly piece. The other side is just an aluminum spacer that holds the shock in place (side to side, it's a clamp) allows for some misalignment (same as on the chromoly side, cut at 30 degrees .130" in depth), that uses a counter sunk bolt to keep the spacer in place and provide a flush clean look.

And here it is installed. I added another mount 3/4" lower to gain a little bit of suspension droop at Stephen's desired ride height.

And here it is outside before going home for a bit.

Now it's time for bed. Any questions I will be happy to answer, and I will check back in tomorrow night. Probably late again as my days have been long at the shop lately.