1987 PORSCHE 928 S4
A Fully Sorted Track Car, for HPDE and OTD Events
+ Street Legal
VIN: WP0JB0922HS861215

For most of its life this 1987 Porsche 928 S4 has been a full-blown track/race car that could not be registered to be driven on the street. About one year ago, its owner decided to make it street legal. To that end, a passenger seat was added, racing slicks were replaced with ultra-high performance Michelin Pilot Sport Cup 2 street tires, the wild yellow and blue paint scheme was changed to all blue (*See the last picture #42 in the photo gallery for its former race livery), the car was titled and registered so it can now be legally driven on the street. But make no mistake – this car is still a 600 horsepower highly modified track car – but it is now street legal.
This is a very well sorted track car that is an absolute monster on the race track, yet extremely reliable.

The car has been extensively upgraded using only the best parts available without concern for the costs incurred. A Pro Charger D-1SC supercharger as well as many other engine modifications have been added producing approximately 600 gross horsepower and over 500 horsepower at the rear wheels in a car that has been weight reduced to just 3,000 pounds. The resultant acceleration and top speed are awesome.

But it’s not just the engine that has been upgraded: significant modifications without regard to cost have been made to the body, chassis, suspension, steering, brakes, electrical system, interior, wheels and tires. The end result is an extremely fast, safe and reliable track car capable of extremely low lap times topped off with a state of the art data gathering system to help you analyze your every movement on the track. Two binders detailing the upgrades and including receipts are included, as well as three sets of Pirelli racing slicks. A video of the car at speed at Waterford hills Raceway is available on request. Seller may consider an interesting trade.

See below for a detailed description of all the upgrades:

• Meticulously built, well sorted and obsessively maintained over the last 4 years
• Fast, reliable performer (1:15.20 best lap time at Waterford Hills on Sep 12, 2020)
• Supercharged, with 15 psi max boost, original 5.0 liter Porsche V-8, estimated to have 500+ WHP
• Electromotive Tec-3 ECU, Panasonic Toughbook laptop programmer/data logger included, dual electronic ignition
• Two Kirkey racing seats, Lifeline fire system, RJS 5-point harness, Roadkeeper video and track data logger
• Numerous engine, suspension, body and other track performance upgrades
• Timing belt, accessory belts & water pump replaced in Apr 2020, with 15 hours total time since their installation

• Pro Charger D-1SC custom mounted centrifugal supercharger, with K&N air filter fitted with water sleeve, silicone hoses, aluminum tubing fresh air induction mounted behind L/H headlight , custom Mishimoto high efficiency air-to-air intercooler, thermal wrap on air induction components, G-Reddy modulated blowoff valve with a secondary redundant full flow by-pass valve, 15 psi max boost
• Custom fabricated 3” dual stainless steel exhaust with performance x-pipe and dual Magnaflow mufflers, with a single “pipes” muffler with internal x-pipe and a bolt on Waterford Hills noise reduction pipe is included
• Electromotive Tec 3 dual ignition electronic control system and ECU unit, fully optimized with a race tune setup for track use, with Tec 3 tuning program software and real time data logging, controlled and recorded on a removable Panasonic Toughbook mounted to passenger floor with docking station
• Clewitt Engineering ignition wires
• Upsized 42 psi Bosch fuel injectors, adjustable engine rev limiter (now set to 5700 RPM, with engine redline of 6200 RPM)
• Custom cooling system with a full aluminum racing radiator, high flow volume thermostatically controlled electric radiator fan, two water pumps; the Porsche belt driven mechanical water pump as originally fitted, plus a secondary electric centrifugal water pump that supplies flow through two custom fabricated engine coolant radiators mounted in each front wing, all silicone hoses and aluminum tubing
• Precision Motorwerks windage and crank scraper system
• 3 quart Accusump engine oil supplement system for low oil pressure conditions with automatic valve deployment set to below 28 psi; accumulator bleeder valve hose plumbed below to undercarriage
• Modified oil pan with 928 Motorsports extended capacity, with an internal cloverleaf baffle design and special oil inlet suction tube system, with total engine oil capacity 0f 12-3/4 quarts
• Custom mounted supplemental Porsche GT2 engine single pass oil cooler; custom built extra length insulated inlet and return fuel delivery hoses by Precision Motorwerks
• Solid aluminum billet engine mounts by 928 Motorsports, engine coolant quick drain valve on engine block
• Crankcase vent catch cans with filtered vents, easy access drain hoses at undercarriage
• Magnetic drain plug on engine oil sump
• Porken timing belt tensioner

• Heavy Duty carbon fiber racing clutch rated for 600 ft-lb, racing clutch hose assembly
• Rebuilt 5 speed manual transmission by COGS-COGS (2019), magnetic drain plug
• Rebuilt 8 plate LSD (2020)
• Custom designed and fabricated transaxle oil cooler with electric pump for oil circulation, dual electric fans and aluminum oil cooler, external pressure and temperature gauges, 5 quart transaxle capacity
• Rebuilt half shafts with new boots

Body, Chassis, Suspension, Steering & Brakes
• Bilstein adjustable coilovers on 4 corners, front springs; 950 lb., rear springs 600 lbs.
• Fully adjustable sway bar links by 928 Motorsports, both front and rear
• Rebuilt steering rack with solid aluminum mounting bushings by 928 Motorsports
• Custom 3 piece frame crossmember by 928 Motorsports that allows for quick oil pan removal
• Stainless steel clad brake flexible lines by Precision Motorwerks
• All four stock calipers fully rebuilt with new pistons and seals, powder coated red (2019)
• Trimmed fender wells with bolt on fender flares for clearance for wheels & tires
• Louvers for air exit on upper surface of both front wings
• Embedded wing mount radiators with flow through forward of wing wheel wells
• Stainless steel wire grating on all air inlet and outlets
• Custom designed and fabricated steel scraper protection wear plates that protect critical undercarriage & engine from front end damage
• Custom designed and fabricated mesh screen skid plate to prevent track debris from entering engine bay and fouling belts
• Hood louvers for oil cooler fresh air inlet and engine hot air outlet
• Front splitter for cooling, front end downforce and underbody airflow
• Mechanically adjustable rear wing for downforce
• Sunroof deleted and replaced with an aluminum riveted blank
• Single driver side windshield wiper
• Lexan rear window
• Pinned hood locks and rear hatch lock
• Dual element carbon fiber rear wing

• Optima yellow top deep cycle battery (2019)
• 90 Amp lightweight alternator (2019)
• Lightweight starter (2018)
• Emergency electrical master on/off switch
• Permanently mounted on board battery tender
• Plug ins for GoPro, Roadkeeper, cell phone, Toughbook
• Brake lights only

• Interior completely stripped, lightened and painted black
• Full welded in roll cage
• Roadkeeper 2 camera video logging and data logging system
• Short throw solid ball mount shifter linkage
• MOMO removable steering wheel with hanger hook on passenger side
• Gauges in cockpit for supercharger boost, engine block coolant temperature (Evans waterless), engine coolant temp into radiator, engine coolant temp on return side to engine, engine oil temperature in the sump, engine oil pressure, air/fuel ratio, fuel pressure, hour meter zero at last timing belt/water pump change, tach n/s, Lenova tablet for speed readout and logging, light for Accusump deployment
• Lifeline fire suppression (current)
• Kirkey racing seats for both driver and passenger
• RJS 5 point racing safety harness for both driver and passenger (current)
• Easily removable, pinned Lexan door panel windows for driver and passenger
• Slim profile driver and passenger door racing mirrors
• NACA pinned in ventilation ducts on driver and passenger side
• NACA ventilation duct in driver door

Wheels & Tires
• Fitted with extra long wheel studs at all 4 corners
• Three piece aluminum racing wheels (front 18” x 11”, rear 18” x 12”), media blasted and resealed 2019
• Tires: Michelin Pilot Sport Cup 2 street tires on vehicle, plus three sets of Pirelli racing slicks, with an extra set of wheels
o Front maximum size 320-650/18
o Rear maximum size 335-710/18
o Hubcentric wheel spacers – H&R 25 mm on all 4 corners

• Bosch 44 Motorsports fuel pump
• Car weighs in at less than 3000 lb.

(*See the last picture #42 in the photo gallery
for its former race livery)


Contact Michael at 248-227-8604 or email

Based in Southeast Michigan, is an independent automotive consignment service whose mission is to find and make the optimal connection with the right buyer for your vehicle – while eliminating the stress, uncertainty and unfamiliarity of selling your automobile on your own. We are fellow Car Guys who share your enthusiasm for sports/specialty cars and enjoy putting sellers and buyers together, one-at-a-time. For us, as well as you, it’s personal – and so are our services.
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