928 RS Concept Sketch
06-28-2013, 06:56 PM
#1
Drifting
Thread Starter
928 RS Concept Sketch
I want to transform my 1983 928S 5-speed w/ 63k original well-kept miles into a lightweight 928 RS.
I'd like to find out just how performance focused my 928 could be. The clear coat on my car has failed and
it needs a repaint anyway.
Weight is the only problem with these outstanding Porsches in my opinion. They still look great and are
very enjoyable to get in and drive after 3 decades. The current weight is 3300 lbs.+ for my U.S. spec
1983 sunroof equipped model. The later 928 examples were well over 3550 pounds.
My prototype 928RS needs to be at that magic 10 pounds per horse-power ratio or better. At around 240 HP and 3300 lbs.,
it currently is not.
I don't want to just throw a super charger on this car. Big heavy cars with high HP figures do not excite me.
For me, a simple, light and agile sports car with decent power is just way more fun.
My 928 needs to go on a serious diet.
I don't want to cut or saw-jaw the unit body or doors. I'd like to approach weight reduction like PORSCHE might have
had they offered a 928 RS in 1983. This would have been a great Porsche.
Some 928 RS Build Details:
I always wanted a gulf blue Porsche. Just the thought of it gets me excited.
Most other colors would look bad with my car's navy blue interior, gulf blue will not and will get the RS idea across very quickly.
A 928RS will need hood vents to extract excess engine heat. The vent design should look 1980s
, be subtle and placed in the correct location. If Porsche used them on the 1984 'Daytona Lightweight',
i should do the same for a RS Concept 928. These engine bays get very hot. They fry all that
is rubber and plastic. The intake tubes get extremely hot, venting is a must.
A 'Ducktail' spoiler on a lightweight hatch. The famous 911 ducktail spoiler is something i want to explore on the 928 shape.
It will be tough with the hatch frame dimensions, but since the hatch lock will be removed it is possible. It would not need
to be quite as tall a spoiler as used on the 911 due to the fact that the 928 rear end is much higher than the 911's rear end.
My ducktail design will not ape the 911 ducktail spoiler, it will be designed specifically for the 928 but hopefully capture the flavor of the original.
Weight & Power:
My goal is to get my 928 RS down to 2700 lbs. and bring the U.S. spec motor up in HP from about 240 HP
up to 270 and later with machine work up to over 300 BHP and naturally aspirated.
Porsche always added a little extra performance (at least 10%) to their special lightweight models.
I want more than that.
Future 928 RS or RSR variants could put out well over 330 BHP at this lower weight.
I will add larger interior diameter 'Euro' intake tubes and throttle body and and specify the 'Euro' grind for its camshafts.
Compression ratio will also eventually be raised to 10:1 from 9:1.
An electric 'puller' fan is in place, the belt driven fan and heavy bracket are gone. The air pump is in the trash,
ac components are all gone as well. My exhaust catalyst and heavy rear muffler have retired as well.
The aluminum 4.7 liter V8 already feels happier, revving smoothly and freely with terrific throttle response.
Power steering is on the chopping block and will be removed.
Gone will be all engine accessory belts but for the alternator, this alone adds horse power.
There will be no power windows or locks, no ac, no radio or need for speakers, no power anything.
The center consul shall be shortened to just below the heater/demister controls.
A small battery will replace the o.e. battery. Lexan will reside in place of the hatch and door glass.
A GT3 inspired single windshield wiper will clear the rain droplets on the rare occasion i am caught out.
The rear wiper and its metallic lump of a motor will be deleted. One sun visor as opposed to the four would be an
obvious RS must have touch. Even the ignition key and fuel cap will be lightened in a Porsche way.
There will be no hood or hatch releases and latches and no gas assisted struts to hold them up.
In their place will be lynch-pins and aluminum prop rods. The sun roof will be removed and it gaping opening filled carefully with pre-shaped 20 gauge steel.
The much ahead of their time hidden aluminum bumpers will be lightened. The heavy 3 - piece rear spoiler, rear wiper and power radio antennae
and rear 'bumperettes' are already gone, The openings in the body for their attachment are neatly filled with mild steel and weld already.
I plan to drill the hood hinges and the hatch frame conspicuously along with many more items for weight savings.
These touches will make a statement to onlookers when the hood is raised and held up with its aluminum prop rod.
I will use the 951 (944 turbo) wheels for this prototype RS.
They are 16" x 7" up front and 16" x 8" out back. I like their deeper dish design over the 928 units.
Shorter S4 front springs will slam the car down. New suspension bushings and new Koni adjustable dampers
will help the RS remain stable at the track.
Some other Major Design Features:
To Relocate the Ignition Key to the left side. This is simply a cool Porsche detail but not necessary.
A Simple, lighter interior and lighter upholstery is a must along with the removal of the heavy sound deadening.
Lighter front seats and steering wheel, lighter dash and instrument pod. Unnecessary electrics are to be removed.
The removal of the rear seats. Custom RS door cards, Perlon carpet. Glove box lid deleted, lightweight dash and pod.
A clean rear bumper cover without an exhaust opening. To Delete all unnecessary elements of this Porsche
including headlamp washers.
A Lightweight, open and very loud exhaust which exits at each side in front of each rear wheel. (this screams my Porsche motor is up front!)
This will be a much lighter exhaust design. I will use 1985- 1986 928 lightweight stainless steel tubular exhaust manifolds, these will save
around 35 pounds over using the cast iron manifolds on my M.Y. 1983. They are also beautifully made.
Then, to a custom made Y-Pipe which goes into a collector, and out the sides as shown.
A Subtle RS below the tach needle and a "DEPRESS CLUTCH FULLY BETWEEN SHIFTS" plaque
on the instrument pod would be nice and recall the IROC 911s back in the day.
These are some of the design details which i intend to use to create a 928RS prototype.
If the car turns out to be as fun as i think, i hope to build many more.
-Matt
I'd like to find out just how performance focused my 928 could be. The clear coat on my car has failed and
it needs a repaint anyway.
Weight is the only problem with these outstanding Porsches in my opinion. They still look great and are
very enjoyable to get in and drive after 3 decades. The current weight is 3300 lbs.+ for my U.S. spec
1983 sunroof equipped model. The later 928 examples were well over 3550 pounds.
My prototype 928RS needs to be at that magic 10 pounds per horse-power ratio or better. At around 240 HP and 3300 lbs.,
it currently is not.
I don't want to just throw a super charger on this car. Big heavy cars with high HP figures do not excite me.
For me, a simple, light and agile sports car with decent power is just way more fun.
My 928 needs to go on a serious diet.
I don't want to cut or saw-jaw the unit body or doors. I'd like to approach weight reduction like PORSCHE might have
had they offered a 928 RS in 1983. This would have been a great Porsche.
Some 928 RS Build Details:
I always wanted a gulf blue Porsche. Just the thought of it gets me excited.
Most other colors would look bad with my car's navy blue interior, gulf blue will not and will get the RS idea across very quickly.
A 928RS will need hood vents to extract excess engine heat. The vent design should look 1980s
, be subtle and placed in the correct location. If Porsche used them on the 1984 'Daytona Lightweight',
i should do the same for a RS Concept 928. These engine bays get very hot. They fry all that
is rubber and plastic. The intake tubes get extremely hot, venting is a must.
A 'Ducktail' spoiler on a lightweight hatch. The famous 911 ducktail spoiler is something i want to explore on the 928 shape.
It will be tough with the hatch frame dimensions, but since the hatch lock will be removed it is possible. It would not need
to be quite as tall a spoiler as used on the 911 due to the fact that the 928 rear end is much higher than the 911's rear end.
My ducktail design will not ape the 911 ducktail spoiler, it will be designed specifically for the 928 but hopefully capture the flavor of the original.
Weight & Power:
My goal is to get my 928 RS down to 2700 lbs. and bring the U.S. spec motor up in HP from about 240 HP
up to 270 and later with machine work up to over 300 BHP and naturally aspirated.
Porsche always added a little extra performance (at least 10%) to their special lightweight models.
I want more than that.
Future 928 RS or RSR variants could put out well over 330 BHP at this lower weight.
I will add larger interior diameter 'Euro' intake tubes and throttle body and and specify the 'Euro' grind for its camshafts.
Compression ratio will also eventually be raised to 10:1 from 9:1.
An electric 'puller' fan is in place, the belt driven fan and heavy bracket are gone. The air pump is in the trash,
ac components are all gone as well. My exhaust catalyst and heavy rear muffler have retired as well.
The aluminum 4.7 liter V8 already feels happier, revving smoothly and freely with terrific throttle response.
Power steering is on the chopping block and will be removed.
Gone will be all engine accessory belts but for the alternator, this alone adds horse power.
There will be no power windows or locks, no ac, no radio or need for speakers, no power anything.
The center consul shall be shortened to just below the heater/demister controls.
A small battery will replace the o.e. battery. Lexan will reside in place of the hatch and door glass.
A GT3 inspired single windshield wiper will clear the rain droplets on the rare occasion i am caught out.
The rear wiper and its metallic lump of a motor will be deleted. One sun visor as opposed to the four would be an
obvious RS must have touch. Even the ignition key and fuel cap will be lightened in a Porsche way.
There will be no hood or hatch releases and latches and no gas assisted struts to hold them up.
In their place will be lynch-pins and aluminum prop rods. The sun roof will be removed and it gaping opening filled carefully with pre-shaped 20 gauge steel.
The much ahead of their time hidden aluminum bumpers will be lightened. The heavy 3 - piece rear spoiler, rear wiper and power radio antennae
and rear 'bumperettes' are already gone, The openings in the body for their attachment are neatly filled with mild steel and weld already.
I plan to drill the hood hinges and the hatch frame conspicuously along with many more items for weight savings.
These touches will make a statement to onlookers when the hood is raised and held up with its aluminum prop rod.
I will use the 951 (944 turbo) wheels for this prototype RS.
They are 16" x 7" up front and 16" x 8" out back. I like their deeper dish design over the 928 units.
Shorter S4 front springs will slam the car down. New suspension bushings and new Koni adjustable dampers
will help the RS remain stable at the track.
Some other Major Design Features:
To Relocate the Ignition Key to the left side. This is simply a cool Porsche detail but not necessary.
A Simple, lighter interior and lighter upholstery is a must along with the removal of the heavy sound deadening.
Lighter front seats and steering wheel, lighter dash and instrument pod. Unnecessary electrics are to be removed.
The removal of the rear seats. Custom RS door cards, Perlon carpet. Glove box lid deleted, lightweight dash and pod.
A clean rear bumper cover without an exhaust opening. To Delete all unnecessary elements of this Porsche
including headlamp washers.
A Lightweight, open and very loud exhaust which exits at each side in front of each rear wheel. (this screams my Porsche motor is up front!)
This will be a much lighter exhaust design. I will use 1985- 1986 928 lightweight stainless steel tubular exhaust manifolds, these will save
around 35 pounds over using the cast iron manifolds on my M.Y. 1983. They are also beautifully made.
Then, to a custom made Y-Pipe which goes into a collector, and out the sides as shown.
A Subtle RS below the tach needle and a "DEPRESS CLUTCH FULLY BETWEEN SHIFTS" plaque
on the instrument pod would be nice and recall the IROC 911s back in the day.
These are some of the design details which i intend to use to create a 928RS prototype.
If the car turns out to be as fun as i think, i hope to build many more.
-Matt
Last edited by The Fixer; 01-10-2014 at 09:08 AM.
06-28-2013, 07:20 PM
#3
Like everything except the ignition on the other side.
06-28-2013, 07:43 PM
#6
Rennlist Member
Trending Topics
06-28-2013, 08:40 PM
#8
Archive Gatekeeper
Rennlist Member
Rennlist Member
To save precious seconds during LeMans starts. Read your history, people!
06-28-2013, 09:17 PM
#9
Drifting
Thread Starter
Porsche always had the key on the left side /left hand drive, thought it would set off the build as the door opened.
Question regarding ducktail; it would work better to get rid of the key latch and have a clean look,
I was thinking rubber straps that the RSR's used may be kind of junky in the end and regretted, and the o.e. latches for the hood and hatch aren't very heavy imo.
Isn't it easy to add an auto hatch release like the later cars have?
'83 doesn't have it, use key still.
Have a lot of ideas that i've been thinking about for a long time regarding this car, will keep you Guys up to date. Too much don't want to be a bore.
Trying to use Porsche parts whenever possible.
Question regarding ducktail; it would work better to get rid of the key latch and have a clean look,
I was thinking rubber straps that the RSR's used may be kind of junky in the end and regretted, and the o.e. latches for the hood and hatch aren't very heavy imo.
Isn't it easy to add an auto hatch release like the later cars have?
'83 doesn't have it, use key still.
Have a lot of ideas that i've been thinking about for a long time regarding this car, will keep you Guys up to date. Too much don't want to be a bore.
Trying to use Porsche parts whenever possible.
Last edited by The Fixer; 09-16-2013 at 04:48 PM.
06-28-2013, 09:28 PM
#11
Drifting
Thread Starter
06-28-2013, 09:32 PM
#12
Nordschleife Master
Porsche always had the key on the left side /left hand drive, thought it would set off the build as the door opened.
Question regarding ducktail; it would work better to get rid of the key latch and have a clean look,
I was thinking rubber straps that the RSR's used may be kind of junky in the end and regretted, and the o.e. latches for the hood and hatch aren't very heavy imo.
Isn't it easy to add an auto hatch release like the later cars have?
'83 doesn't have it, use key still.
Have a lot of ideas that i've been thinking about for a long time regarding this car, will keep you Guys up to date. Too much don't want to be a bore.
Trying to use Porsche parts whenever possible, i.e. my hood and hatch will be held up with the lightweight aluminum arm that is used in the first generation Cayenne to hold up the spare tire lid. Looks just like what the 70s RSRs had. I like that about Porsche.
Question regarding ducktail; it would work better to get rid of the key latch and have a clean look,
I was thinking rubber straps that the RSR's used may be kind of junky in the end and regretted, and the o.e. latches for the hood and hatch aren't very heavy imo.
Isn't it easy to add an auto hatch release like the later cars have?
'83 doesn't have it, use key still.
Have a lot of ideas that i've been thinking about for a long time regarding this car, will keep you Guys up to date. Too much don't want to be a bore.
Trying to use Porsche parts whenever possible, i.e. my hood and hatch will be held up with the lightweight aluminum arm that is used in the first generation Cayenne to hold up the spare tire lid. Looks just like what the 70s RSRs had. I like that about Porsche.
Kind of like... our Picasso.
Power to you !
06-28-2013, 09:43 PM
#13
Archive Gatekeeper
Rennlist Member
Rennlist Member
Need a balsa wood shifter from a CGT. Or from a 917.
There's all sorts of cool old Porsche DNA that can be adapted (adopted?)
There's all sorts of cool old Porsche DNA that can be adapted (adopted?)
06-28-2013, 09:55 PM
#15
Captain Obvious
Super User
Super User
