vw tdi kit car

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
As the owner of www.factoryfive.com I wanted a kit car that would appeal to my daily driver buddies and others who already own one or more of our high performance kits.

I am on twitter at www.twitter.com/factoryfive if you are into these projects and I am trying to do this live with the help of the various online communities that support the vw's(the factory five community connects on www.ffcars.com)

the thread that reviews our progress to date is called "mark smith...time to talk) and I figured it was time to get the input of the die hard tdi community.

I am just at the point where we are choosing the body shape and top configuration so any advice is welcomed. Here is the concept for those that have not heard of it:

Gen iv golf or jetta tdi

cut rear off the car

cut the front off the car just forward of the front suspension mounts

cut roof off the car

lower dash 6" and lower seats 6"

move the tdi fwd engine and gearbox to the rear for a mid engine sports layout.

modify the front upper suspension to accom a no strut shock system

add front and rear subframes to hld engine/fuel tank batt etc

we call it the G3f (go green go fast) and the new company I started to launch it is separate from factory five and is called Smyth performance, inc.

have fun.

mark smith
fact5 at comcast dot net
twitter "factoryfive"
www.twitter.com/factoryfive
www.ffcars.com(factory five discussion site)
 
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Pat Dolan

Veteran Member
Joined
Apr 19, 2002
Location
Martensville, SK
TDI
2003 A4 Variant, 2015 Q7
Many years ago, when I was a boat builder, we thought seriously about building a Rabbit-based kit. Ended up doing the prototype in aluminum welded monocoque, VW drivetrain at the rear, used VW strut rear suspension, SLA front suspension (using rear coilovers for front suspension), and a VERY clean and light body. Ended up weighing about 1,200 lbs., was the perfect home for a diesel, but we ended up doing different projects. Still have the car, body gone when toolmaker went TU and new owners "lost" the plug. Would love to do this again (but would not go the exotic material route).
 

CFM

Veteran Member
Joined
Dec 13, 2006
Location
Wells, Maine
TDI
1995 Saturn with a 1997 TDI drivetrain.
With a little work, that FF '33 coupe kit you offer would make a really cool mid-engine TDI driver.
 

vdubdezl

Veteran Member
Joined
Sep 19, 2007
Location
FL
TDI
06 Jetta TDI 5MT, 05 Honda Odyssey EX-L
I've always loved your cobras and the new gtm is awesome....i just have one problem with these cars....no back seat. How about something ultra-sporty like the gtm with a back seat and tdi for fuel milage so you can drive it anywhere without feeling guilty??


Also mark...how about some pics of mini me???
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H
CFM said:
With a little work, that FF '33 coupe kit you offer would make a really cool mid-engine TDI driver.
My thoughts too. Full top, full fendered, fo me please. But I'd consider keeping the front engine layout, a 1.9 TDI put north-south and driving a Toyota gearbox (or other pre-engineered bellhousing/adapter set) and then back to the ring and pinion rear axle. If for no other reason than to keep the cost down to something only just out of my reach.
 

Pat Dolan

Veteran Member
Joined
Apr 19, 2002
Location
Martensville, SK
TDI
2003 A4 Variant, 2015 Q7
Mark:

In keeping with your RWD layout, were you contemplating an open or closed car? "Sports car" or street rod (from the sounds of your suspension ideas, I am guessing the former).

IMHO, sticking with the A-series platforms (probably MkIV for availability) and designing the whole thing to roll in a donor car on one side, and your kit from the other would be important. I don't think cutting the car apart is a good idea. I believe you will find that removing parts from one to bolt into another is a lot more saleable (yes, we did the market research, but I think this is what you ALREADY do with your 5 litre Cobra kits, not so?)
 

Whitbread

Vendor , w/Business number
Joined
Jan 21, 2007
Location
Johannesburg, MI
TDI
Several
After driving a Pontiac Fiero for the past couple weeks (since my tdi is still down), I can't help but think how much fun it would be with a ~200hp tdi and a 6 speed. I'm seriously thinking about finding an 88 GT with no motor or tranny for my next project :).

Saying that, I think a rear engined kit car along the same lines would be amazing. Make a 99.5-04 engine cradle drop in and you'd be set.

BTW - The gtm and street rod kits are pure automotive sex on wheels. Keep up the good work ;)!
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
2010 Touareg Tdi w/factory Tow PCKG
fact5 said:
Gen iv golf or jetta tdi
cut rear off the car
cut the front off the car just forward of the front suspension mounts
cut roof off the car
lower dash 6" and lower seats 6"
move the tdi fwd engine and gearbox to the rear for a mid engine sports layout.
modify the front upper suspension to accom a no strut shock system
add front and rear subframes to hld engine/fuel tank batt etc
we call it the mini me as it somewhat resembles a factoryfive gtm right now...but a bit smaller.
have fun.
mark smith
fact5 at comcast dot net
twitter "factoryfive"
www.twitter/factoryfive
www.ffcobra.com (factory five discussion site..not related to cobras or shelby in any way whatsoever)
How about:

1. Cut car at firewall.
2. Remove front fenders, bumper skin, hood.
3. Weld up a light-weight, compact aluminum tube-framed 3-wheel!, 3- passenger chassis to firewall.
4. Cover new chassis in fiberglass. Use aluminized, uv-resistant plexiglass windows all around. 3 VERY light seats (2F, 1R in center). Egress/Ingress via hinged clamshell style door that is sealed to the body sill via vacuum (integrate a rubber channel into door sill and/or body sill to the car's vacuum reservoir. Essentially this becomes the new vacuum reservoir for the Tdi. Use a solenoid check valve to isolate from system during ingress/egress from vehicle.
4. Optional: The clamshell style "door" could be counterbalanced at the front to make it easier to open and not require electric lifts or heavy-duty struts.
5. Make new hood, front fenders, and bumper skin to match body style.
6. Delete original wheels and replace with lightest wheel/tire combo available in optional 16", 17" size formats.
7. Minimal gauge pod(s), 2 optional styles in fiberglass or aluminum.

Options:

integral tow hitch receiver.
trunk area over/around rear wheel OR no trunk, expose and show off rear wheel and suspension.

Design goals:

1. Car should have 20% less frontal area than donor MarkIV vehicle.
2. Car should have 35-40% less mass than donor MarkIV vehicle.
3. Center of gravity should be at least 4.5" lower and as far forward of its geometric center than donor vehicles.

This car would get 25-35% better fuel economy (or more) and be a hoot to drive, while being able to tow MORE than a donor MKIV due to light weight and tube-framed chassis.

If you can do that then tell me where to send my check please :D
 
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Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H
nicklockard said:
How about:
4. Optional: The clamshell style "door" could be counterbalanced at the front to make it easier to open and not require electric lifts or heavy-duty struts.

Design goals:
3. Center of gravity should be at least 4.5" lower and as far forward of its geometric center than donor vehicles.
Clamshell (or gullwing) doors are notorious weight adders. Not so much the doors, but their support structures in the roof. Hinge points, gas strut mount points, the gas struts themselves have to be much stronger because they have to hold the door up, not merely 'out'. The added weight up at the top of the vehicle, even if only 1/2 of the door set is attached there, does not fit in with the desire of a lower weight and a lower Cg.
A counterbalance effectively doubles the doors weight.

Does the door window reside in the top half of your clamshell? Into what does the glass move when it is desired to open the window?
 
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nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
2010 Touareg Tdi w/factory Tow PCKG
Lug_Nut said:
Clamshell (or gullwing) doors are notorious weight adders. Not so much the doors, but their support structures in the roof. Hinge points, gas strut mount points, the gas struts themselves have to be much stronger because they have to hold the door up, not merely 'out'. The added weight up at the top of the vehicle, even if only 1/2 of the door set is attached there, does not fit in with the desire of a lower weight and a lower Cg.
A counterbalance effectively doubles the doors weight.

Does the door window reside in the top half of your clamshell? Into what does the glass move when it is desired to open the window?
You're right. A clamshell style door is usually heavier. But I've said all windows should be Plexiglass, so that reduces weight a lot. Yes, I would have windows integral to the lid, otherwise weather sealing could be a nightmare. Also, instead of a counterweight, how about a spring pulley placed low in the front of the car to help lift the lid?

You're right about a counterweight too: a counterweight is not the way to go, as it would add too much weight. With a spring-pulley, you would not even need a light weight strut. You could make the spring force equal to or slightly stronger than the force required to open. And the spring pulley could be a cam-style pulley so the help would be nill at first but actually lift the door beyond an initial effort. You'd only have to use a little force to start to open it; the spring pulley could do the rest. I could imagine a spring pulley (steel coil spring + aluminum pulley + poly-sheathed steel cable + aluminum mounting bracketry) of no more than 6.5 lbs.
 
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mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
delayed read

Sorry I missed the thread guys...was looking for it in news...

Just to clear up a bit..

the ffr gtm is a great hipo supercar but the cost and complexity of the kit can put the finished car price into 50k +...not what i was looking for.

I love having the firewall and all the accesories from the tdi remain in the car for ease of assembly...those items take a ton of time for our customers to install.

the transverse engine layout is not my favorite but the packaging and ease of finding donor drivetrains can't be beat. If I can keep the kit below 10k people are driving a 2000 lb reeeally fast mid engine 55-60mpg commuter sports car for 15 grand..how fun is that in the home built world I deal in:)

so yes follow along on www.twitter.com/factoryfive or www.ffcobra.com the thread is called "mark smith time to talk:)"

So far a great reception from the closet diesel guys(a few vr6 turbo guys too) who are part of the 8000 strong factory five customer base...good times indeed.


mark smith
2002 135hp tdi wagon, 2000 tdi wreck currently being cut/transformed into first diesel production kit car.
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H
Below 10K? as in $10k? You WILL be my hero.
The looks beat the heck out of the $5k conversions I have done.
Should I start searching for an ALH donor now?
 

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
below 10k

The key is using all the donor stuff that we can. Body, front and rear subframe, shocks etc...we do that well and in volume at factory five...using the seats..upper dash...all the front drive parts in the rear...lower half of the front suspension..that is where the sub 10k price for the kit gets possible.

The coolest thing about the jetta floorpan is the fact that you are reconfiguring an existing car into something new..too cool. We will see.

www.twitter.com/factoryfive

mark smith
 
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nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
2010 Touareg Tdi w/factory Tow PCKG
Under $10K?

Now I'm interested. Will frontal area be reduced much from the donor car? Can you post a front and rear profile of your car up against the front and rear profiles of a Jetta or Golf please? With same scaling so I can calculate the % difference in frontal area from that and post it--if you haven't crunched the numbers yet, that is.
 

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
car is 44 inches high and the windshield is 56" wide at the bottom and 45" at the top..lower frontal area yes..calcs no. 2000 lbs and low and mid engined...some concepts make so much sense you just build the bugger and go without the math:) we are used to the 200 mph stuff..this is easy so far.
mark
 
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Scott_DeWitt

Vendor
Joined
Apr 7, 2004
Location
Texas USA
TDI
2000 Audi A4 1.9TDI quattro
fact5 said:
The key is using all the donor stuff that we can. Body, front and rear subframe, shocks etc...we do that well and in volume at factory five...using the seats..upper dash...all the front drive parts in the rear...lower half of the front suspension..that is where the sub 10k price for the kit gets possible.

The coolest thing about the jetta floorpan is the fact that you are reconfiguring an existing car into something new..too cool. We will see.

www.twitter.com/factoryfive

mark smith
Hmm interesting concept.

The FWD cars have no rear subframe, the only rearward part of the car sturdy enough to support and engine is the axle mounts forward of the axle. There is little rearward structure capable of supporting the weight and torque of an engine, unless brackets are welded to the frame rails which are rather thin when compared to the front rails.

Also the width of the frame in the rear is quite narrower when compared to the front. The front rails curve outward and upward to accommodate the width of the engine/transmission.

However I think the majority of the market would be the gasser crowd, as the number of gas engine's VW out there surpass diesel powered engines by several orders of magnitude. Although a properly designed kit would have the ability for the builder to use either the VR6, 2.slow, 1.8t or 1.9tdi.

But since I've mentioned gas engines, you might want to look at the B5 audi A4 quattro. There is sufficient structure in the rear to mount the transverse engine, and a TDI will bolt up with relative ease to the existing gearboxes.
 

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
sub frames and sheetmetal floors

the floorpan and rear cant hold a thing. A complete rear subframe(imagine an ffr gtm rear) will bolt to the rear pan and include several tubes that run all the way forward to the front door jam. I have some pictures on twitter to get the idea across but this month I am fabricating/drawing the frame.

The front gets the same treatment with a full tubular subframe that mounts up to several hardpoints on the cowl...easier since the cowl area is full of really beefy mounting points.

One of the benefits of racing cars and delivering over 8000 kits to customers who run an average of 400hp to the wheels is you get real good at solidworks and torsional rigidity issues in small cars:)....most of our cars are 2300 lbs and run big hp numbers...even a turbo vr6 looks tame compared to a vette ls7 or a big block 427...and this little jetta will benefit from all that learning...good fun indeed.

So enjoy the show..I have never done a car in public at such an early phase..it has been a ball so far. the hybrid floorpan/subframe idea that uses the jetta title has real possibility in the kit car world since titling and smog regs can be hard on home built cars.

have fun and yep...the frame will be strong enuf for the wildest 1.9 tdi you guys can build...I am counting on it.
 

Lug_Nut

TDIClub Enthusiast, Pre-Forum Veteran Member
Joined
Jun 20, 1998
Location
Sterling, Massachusetts. USA
TDI
idi: 1988 Bolens DGT1700H
Saturday looks like a rain-out. Sounds like a perfect day for a field trip to Wareham.
Do you schedule facility tours on Saturday's?
See the PM I sent for my contact information.
 

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
ffr does...the new diesel car is in my facility down the street and isnt ready for visits yet...but soon
 

shortysclimbin

Veteran Member
Joined
Oct 15, 2004
Location
Virginia currently
TDI
Kubvan, mk2 golf, mk6 golf
So are you building the frames from Tube aluminum? :) and are these vacuum bagged bodies? I just happen to have a spare motor... HMMMM next project...

I would be very happy if you actually used the audi tt front suspension components or custom designed them into the frame. And if it could take golf r32 front seats It would be a very comfy ride too!
 

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
frame

dom steel tube..aluminum sheet for trunk etc. FFR does the steel alum combo and this is no different.


re seats etc..if it fits in a jetta cockpit it will probably fit here:)

mark
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
2010 Touareg Tdi w/factory Tow PCKG
Okay, I'm trying to visualize this build. But I have some questions:

You're saying the front suspension will be airbag type?

Will you retain Ackerman steering effect or go to neutral steering? What front hubs will you use?

I can't wait to see the frame pics! Sounds like you've got a lot of expertise in these conversions.
 

mark smith

Well-known member
Joined
Mar 19, 2008
Location
wareham, ma
TDI
2000 jetta sedan, 2002 jettta wagon
front suspension

Front suspension is the same hubs/kframe steering rack as on the jetta/golf except that the strut is removed and a coilover shock/upper a arm setup is used. We do this with the roadster kits we sell that use the 5.0 mustang spindle that was set up for a strut..a ball joint and arm go where the strut used to go and you install a coil over race unit. works great and allows for the low hood line without the strut bumps you see on many low strut cars.

The only challenge is that you need another set of spindles for the front since you are moving the existing front spindles to the rear..I am including the new a arms and shocks for the front in the kit.

In general it helps the steering geometry a little bit since the wheel can follow the double elliptical path of an unequal a arm front suspension. The steel cage mounts to the body/cowl and the kframe..should be pretty slick.

Mark smith

www.twitter.com/factoryfive
www.ffcobra.com/forums/showthread.php?t=220382
 
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