Sparkydog's Abnormal Build - 944 With L67 + Ford Stuff & CARB Legal

v2rocket wrote:
Maybe get it certified as an L36 and then L67 it when you get home :p

Yes this has crossed my mind. I need a tranny, bell housing, clutch, flywheel, pedals etc out of an L36 Camaro/Firebird anyway - and I hear that the engine accessories off these same cars work better for running on the L67 in a RWD configuration. The BAR guy already suggested that I run the Camaro/Firebird exhaust system on the L67. So I think I'll buy an entire donor car, harvest all these components along with the L36. If the refs totally reject my attempt at the L67 then I have the option to go "v2rocket" style.

Cool project, I admire your fearless attitude!

I'm finally back on my little hobby. Here's a couple of shots of the Ford Coug 8.8 diff, axle and hub mocked up inside my 944.
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As you all probably already knew - the Porsche diff has the Cl of the driveline above the axle outputs and the Ford diff is the opposite. So in order for the Ford diff pinion to clear the top of the 944's torsion bar housing it puts the axle CL's about 3.5" above the ride height of the wheels. This is about a 10* - 11* angle for the axle CV joints.

The stock Cougar axles are a little too long to fit inside the 944 swing arms so for mockup purposes I just slid the diff to the side, assembled the axles into the swing arm along with my dummy wheel bearings (same dims as the Porsche bearings just fabbed out of aluminum and slip fit instead of press fit). This allows me to figure out how much shorter of an axle I would need should I opt to really go this route.
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Can anyone confirm that the center section of the Porsche torsion bar housing contains the female splines for the torsion bars to fit into? It looks like a casting that is part of the overall weldment of the housing. Myself and others are wondering because if this is so then cutting this out in order to allow the drive shaft/pinion to run through that area would be verboten. Has anyone ever cut up one of these housings?

Yes i can confirm that the center section does have the splines. I have cut mine out to allow my Z06 six speed trans.

Thanks for the quick reply kevin^2924! I found your build thread and read the entire thing - but about 1/2 the pictures did not display so I could not see if there were any of what you did to the torsion housing. I am assuming you did a Tbar delete and are going to use coilovers? Next I googled 944 tbar delete and tried to read a few of the results - most of them off Rennlist. I'm not sure if I got all of it in the first read through but it sounds like a tbar delete involves some kind of mod to the spring plates? Also a stronger lower shock mount bolt and debate about reinforcement to the upper shock mount area?

After doing the mockups with the Ford IRS diff and looking at the tradeoffs I would have to make I've decided this is not the way to go. As we've all noticed the CL of the driveline wants to run right where the 944 Tbar housing sits. It is possible to do a "Tbar delete" and run coil overs but there are other mods that accompany it. Even then I would be running custom shortened axles so when the CV joints wear out I'm faced with expensive replacements. Since my goal is to try and have a car that is affordable to maintain and repair I think my best option is to ditch the 944 rear suspension and graft in the Mustang setup.

So I pulled out the Mustang junk, disassembled the axle from the floor, cleaned up the floor and then studied where to do some trimming in order to get it down to the essential structure that needs to go into the Porsche.

I ended up with this plan and set about doing the trimming.
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P stuff is out. Different F stuff ready to try and go in.
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Not sure if this helps but here's a pic of Eric's 2002 viper rear differential conversion.

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It was a rough week at work so I gave myself a little fun time this morning. I decided to do some more prep work to the Mustang structural metal while it was easier to work on. So... the axle went back on again, then some more conduit bracing.
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Then the axle came off again. Then I marked up where I wanted to improve upon the Ford factory spot welding.
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And then it was stitch-o-rama for an hour or so until I ran low on shield gas.
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did you consider putting the whole Cougar/Tbird rear end into the 944?
i looked at that for a while and looked like it "might just" fit.

I bought the entire Cougar IRS subframe from the junk yard but not the frame/floor. When I got the whole thing home I saw that the track width is considerably wider and the whole thing was very heavy. The advantage I see with the straight axle & swing arm system is that there are plenty of aftermarket kits/components that I can add or, down the road, there is the Mustang IRS system that essentially bolts up into the same mounting points I am about to add.

I have trimmed progressively more off of the Mustang frame section until now I am at the point where I'm ready to layout where to cut into the 944 arse.
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I designed and built an exoskeleton that bolts up into the 944 so as to help stabilize things once I cut into the rear frame horns.
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And the actual thing...
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And also a reference jig so I can know where the CL of the rear axle is relative to the Mustang frame section.
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So now I am finally ready to cut some big holes in my little friend the 944.
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Over the weekend I did enough trimming/shaving to the 944 that the section of Mustang rear subframe is now at the correct height and fore/aft location. The first picture shows that I have the Mustang frame clamped to the bottom of the 944's structural metal at the bulkhead area.
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I will now need to figure out how to tie these two worlds together so that the forward thrust from the rear wheels is transferred into the 944 unibody in this area.

The second major area where the Mustang and 944 metal must tie together strongly is where I c-notched the 944 frame horns to clearance for the Mustang's upper coil spring bracket.
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It was fun cutting through the upper shock mount bushing...
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The Mustang triangulated 4-link and rear axle are now grafted into the 944 and the tangle of conduit, jigs and alignment doodads has been removed.
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And it's back on the ground after 4.5 months.
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Starting to fill in the numerous holes - beginning with the big ones.
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It's just about 6 months to the day since I decided to graft the Mustang rear suspension attachment metal into the 944. It is officially grafted and in primer now.
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I bought a donor Camaro and have harvested the motor/5spd, fuel system, fuel tank, pedal assembly, etc off of it. Photos of 1st stuff into the 944 below. I also bought a set of SVT wheels and tires and have them mounted.
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I'm about to finalize the location of my motor and start fabricating motor mounts for it. One of the things I looked at for motor location was to provide as much room as possible for the brake booster/master. I now have the option of either fully manual, hydro-boost or conventional vacuum boost. (There is just barely enough room for the larger vacuum boost diaphragm housing.)

So if I have the room to do any of the three types of brake system - which one should I go with?

This is a pretty cool build. I don't know why I never saw it before now. I would definitely source the mustang independent rear diff setup. Unless of course you are mainly building the car for straight-line stuff. The independent rear diff will get you back close to the original 944 drivability in twisty roads.

As far as brakes go, if you have the room, I would use the vacuum booster. It is much simpler than hydroboost to hook up. Otherwise, use hydroboost. Manual brakes just lack in braking overall.

What engine and trans is that? I can't see it well enough in the pics to tell. You're doing what I am planning on my car by putting the trans on the back of the engine.

I have both an L36 and an L67 that I've been stuffing into it. I'm going to get it running and street legal with the L36. I harvested the L36 with a T5 out of a 96 Camaro.

Motor mounts are fabbed, primered and tacked in on the K member.
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On the other end of the car - I have sourced a gas tank that I like. It's square, wide, tall and short in the correct directions and fits into the cavity of the 944 like it was made for it. On the other hand - the filler neck will require mods and it is not (yet) compatible for a late model fuel injection pump and modern vent requirements.
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Starting on the transmission cross member and mount.

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Can somebody get me the approximate distance from the floor pan up to the center of the clutch pedal? Also state if you measured with or without carpet. I would prefer the distance without carpet but will take whatever you can give me! Thanks!

Not exactly sure what your asking. This is straight up from a high ridge of the bare floor.

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