Earlier this year installed one of the few remaining TurboTechnics UK twin turbo kits on a 63K mile M103-12V with 190-200PSI compression readings in all cylinders.
Kit included cast manifolds, chassis rail mounted intercooler, and twin Garrett T2 turbos set at a fixed 7LB boost.
Kit was a "bolt on" in many respects.
Modification and modernization to a kit built in 1992 produced a much better install.
Suspension was modified to accept the additional power.
Mods include H&R lowering springs ( about 1.5" drop ), Bilstein HD struts/shocks, Sportline front/rear swaybars, new motor mounts, Zimmerman cast drilled rotors/Textar pads, 18x8 ET35 AMG replica rims with 225/40-18 Falken FK452 rubber.
The main "additional power mod" was replacing the supplied piggy back fuel enrichment control with a stand alone 3D mappable computer programmed control by Split Second.
This controller allowed 12.5 AFR through boost.
The other significant mod was to replace the intake and boost coil hose with aluminum tube and smooth silicone hose and replacing the supplied Fram panel filter with a free flowing K&N panel filter.
A true cold air intake was obtained by drawing air from the intercooler plenum opening in the Wald EX spoiler, approximately where the stock tow hook cover is located.
Air in must equal exhaust out, so the exhaust system comprised of two x 2.5" down pipes to two inline Magnaflow spun metal cats ( #59954 ) then 2 x 2.5" pipes back to the supplied TurboTechnics rear silencer ( 2 x 2.5" in and 2 tips out )
Base line dyno ( Mustang load dyno ) was 136HP/146Torque against a published 177HP/188Torque.
This indicated a 30% drive train loss on the load dyno.
Keep in mind a load dyno reads typically about 18% lower then an inertia type dyno.
The basic kit install with the Split Second control produced 197HP/221Torque with the torque peak moved to 4250RPM from 4500RPM with HP peak remaining at 5500RPM.
The intake/boost/filter change was significant raising the numbers to 208HP@ 5200RPM and 239Torque @ 4000RPM.
Dyno pulls were done in 85 degree + ambient.
Cooler temps produce much more power.
To calculate flywheel HP we add back the 30% and factor in the 18% dyno difference as most tuners use inertia type dynos.
208HP x 1.3 x 1.18 = 320HP
239Torque x 1.3 x 1.18 = 367Torque.
The figures published by TurboTechnics in 1992 were 300HP/300Torque for the M103-12V.
Best 0-60 mph ( using G-Tech 3 axis accelerometer ) was 5.49 seconds in 90deg F ambient, pre intake/boost mod.
After intake/boost mod times were in the 5.2 second range.
This almost confirms the HP/torque readings based on a 3700 lb vehicle.
Failed to get to a 1/4 mile this year, but will do some runs when the track opens.
Estimating with 60deg F ambient, 0-60mph around 5.0 seconds and a 13.5-13.7 1/4 @ 100-104MPH.
Not inexpensive, professionally installed by one of the few tuners who is still familiar with the CIS-KE Bosch Ke-Jetronic III injection system.
Total cost including suspension, exhaust, TT kit install, motor mounts etc. was around $15K.
Manhours ran at 110.
This including a good bit of time figuring out mismatched parts and resolving issues in the supplied kit.
Could probably save 20-30 hours if done again.
Added 143HP and 179 torque which equates to about $100/HP.
Vehicle still is stock as far as settings of the CIS-KE unit and only change is under boost with enrichment via two additional injectors mounted between the air valve and throttle body.
I'm sure more HP can be produced from a M103-12V by converting to fully electronic injection and using larger turbos with higher boost.
This is not for me as I wanted a "period" install with a result of performance equal to a NA AMG V8, exceeding the 500E/E500 and the earlier Hammer and approaching the 6.0 Hammer.
Not bad for a 3.0L SOHC motor !!!
ORIGINAL INTAKE/BOOST PIPING 
MODERNIZED PIPING 
AIR FILTER COMPARISON 
COLD AIR INTAKE PIPING 
INTERCOOLER 
SPLIT SECOND ADDITIONAL INJECTOR CONTROLLER 
FINISHED PRODUCT ! 
