Juicing the 911 SC-L 3.1 Leistungsgesteigert

[Henry Schmidt]

Engine type 930.03 or 930.09 * 3.1 *
Engine displacement: 3122 cc
Bore x Stroke: 97mm x 70.4mm
Power: 210 hp @ 5900 rpm Binary: 280 Nm @ 4300 rpm
0 at 100 km / h: 6.4 seconds Max speed: 230 km / h

The Forgotten 911SC-L
Porsche's 1st factory tuning engine kit that was NOT in the option list for those years (Dealer Secret)
Rolf Sprenger, The Father of the Porsche MFI for the road cars and the Slant Nose 930
Designed this 3.1, 210hp Tuning kit for customers that were not happy with the output and performance of the normal 911SC 3.0 78-81
This tuning kit has a output of 210HP @5800 RPM and 206 Torque @ 4700rpm
Roth used 97mm 3.3 Turbo Cylinders with 9.5:1 compression Pistons made it 3122CC

3.1-L Engine Leistungsgesteigert or Increased Power
Bosch reworked the CIS injection with new Distributor
Taller 5th gear and larger oil cooler from the race department
3750.00 dollar Option in 1978
ONLY spread word of mouth at Porsche Dealers showroom
when customers voiced displeasure of the performance of a normal 911SC
Never was available in the USA only Europe and ROW and only a Letter from Rolf was included in the glove box with this upgrade
No way of knowing how many of these tuning kits were made
Some estimate 200-300 unit made
Roth Sprenger Personal notes and Porsche refusal to Market the SC-L
almost left no documentation to this special rare 911.

We are replicating this unique forgotten option for immediate sale .
Click the link and you're on your way.
Porsche 911SC-Leistungsgesteigert Piston & Cylinder kit.

[Classic 911]

Real nice power kit this


Sent from my iPhone using Tapatalk

[spunky.goat]

Are the performance numbers noted specific to a large port engine?

How well would this set-up work w/ a US Spec small port (1980) engine?

[fabracadabra]

Pondering that same question.

[Henry Schmidt]

Originally Posted by spunky.goat

Are the performance numbers noted specific to a large port engine?

How well would this set-up work w/ a US Spec small port (1980) engine?

The biggest challenge with boosting performance with this generation of 911SC is the smog equipment. This engine is Porsche first attempt at a lean burn 911. Earlier 911 engine were rich running with an after-burn smog system. Air pump, thermal reactor, EGR system, ECT.
In the 1980 and later (small port engine) they incorporated an oxygen sensor triggering a frequency valve that adjusted the fuel distributor to create a lean running condition. Then they put that exhaust through a catalytic converter,
The larger pistons with slightly higher compression can only be beneficial to any measurable extent if you can meet the additional fuel requirements to create the performance desired.
So the answer is, the kit will only add performance if properly tune. That may require a cleaner exhaust, a better fuel distributor, removal of smog equipment and of course cams.
As far as the small ports and runners are concerned, as long as the goal is performance under 6400 rpm, the small ports can prove to be easily workable.

[Henry Schmidt]

The 3.1 L Wedge

[Henry Schmidt]

An additional thought:
With some creative rod configurations and crank combinations you can make 3.3.

[Henry Schmidt]

Holiday Bump

[Henry Schmidt]

Still available