3.0 Performance engine build

[AintGotNoGasInI]

Just wondering what some of yours guys experience is with building a 3.0 Hot Rod for street use



Biggest questions

What Piston and cam combo seems to be ideal for a torquey street rod?

where is the law of diminishing return on parts?

Is going to a large intake head worth it? does it impact streetablilty greatly?

[PeteKz]

First important question: What's your budget? Yeah, I joke about "budget" and "Porsche" in the same sentence too, but you must have some number in mind to start. You probably will go past it, but not as much as if you don't have a budget to start with.

What are you starting with? Do you have a core 3.0 SC engine? Or do you have to buy an engine too? Do you plan to use the 3.0 SC CIS fuel injection system, or will you install carbs or throttle body FI? Will you do most of the work? Etc.

[911 Vintage Par]

Supertec has a pretty cool upgrade for 3.0 builds

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

Originally Posted by Henry Schmidt

Porsche 911SC-Leistungsgesteigert (Performance increased)

We're making sets using 95mm cylinders bored to 97mm and plated by Millennium. CP X-brace pistons are then custom fitted. Any compression (with reason) is available but we stock a 10:1 version on the shelf.
The pistons are designed to use 3.3 liter turbo rings so replacement is affordable and easy.
$ 3.575.00 plus shipping

We also have a new version in stock and ready to ship.
The new version has a wedge dome to more accurately replicate the original 3.1L
Porsche 911SC-Leistungsgesteigert performance kit.
$ 3.775.00 plus shipping.

We will include a reground set of Carrera cams. The new profile is 964.
When purchased at the same time as the piston and cylinder set, the price is $625.00 exchange. You can exchange 911SC or Carrera cams for the core.

SUPERTEC PERFORMANCE
Ph: 760-728-3062
Email: supertec1@earthlink.net

[Rosco_NZ]

Wow that looks like a high comp piston!

[Racerbvd]

Originally Posted by 911 Vintage Par

Supertec has a pretty cool upgrade for 3.0 builds





SUPERTEC PERFORMANCE
Ph: 760-728-3062
Email: supertec1@earthlink.net

I’d love this for my 78.

[Henry Schmidt]

Originally Posted by Rosco_NZ

Wow that looks like a high comp piston!

With .040" deck it's designed to create 10:1 compression. 9.5:1 with .060" deck.

[Billiam 911 2.8]

Am I the only one who gets tired of people not checking for previous discussions about the topic they bring up? Should not be some genie in a bottle kind of thing. Put it some effort and then ask for help based on the information already available.

[Henry Schmidt]

Originally Posted by Billiam 911 2.8

Am I the only one who gets tired of people not checking for previous discussions about the topic they bring up? Should not be some genie in a bottle kind of thing. Put it some effort and then ask for help based on the information already available.

I might be an old fart with limited computer skills, but my experience is that the search engine on PP isn't always that productive.
This forum is for people with questions about how to get through a rather challenging process, so ask away. I guarantee you're not the only person in a quandary about your problem.
I'll also guarantee that some of the answers you'll get will be pure bullshyt. Grain of salt method is advised.

[Billiam 911 2.8]

Since this was a "one and done" post with my complaint coming days later, I don't consider it to be a serious inquiry. There are books with foundational knowledge on the subject of air cooled Porsche engines and their performance enhancements ("Bruce-Wayne"). I see it as respect for the professionals and well informed hobby mechanics here.

[shbop]

Originally Posted by Billiam 911 2.8

Am I the only one who gets tired of people not checking for previous discussions about the topic they bring up? Should not be some genie in a bottle kind of thing. Put it some effort and then ask for help based on the information already available.

Looks like it was his first post. Lighten-up!

[Stevepro]

I recently rebuilt my '76 Carrera 3.0 engine with Henry's 3.1 piston and cylinder upgrade as shown above and included a pair of William Knights M1 Cams. This engine is very lively. I also have a '75 911S with a Euro 3.2 Carrera engine which feels lazy by comparison.

3.1 upgrade with M1 cams highly recommended.

[Rick Cabell]

Stevepro, I was about to do the same with my 77 3.0 Carrera. Just wondering why you chose the M1 cam instead of what Henry was offering. I am assuming you are still running the original CiS.

[AintGotNoGasInI]

Hey guys,

fist post here and have been working out of the country,

Thank you guys so much for all the information and help, I can believe how much support there is!

this is the first i have heard of the 3.3L and I believe this is the way I am going to go.

I defined my plans and have begun ripping out ALL the old harness and wiring a Haltech Nexus R3 and PD16, im running the entire car off both of these units with new wires, once Im happy with the wiring I am moving to the engine rebuilding phase with a stock bottom end and 3.3 cylinders, a bit more cam as well (have not decided which cam to go with, looking at the DC-40)

[AintGotNoGasInI]

Hey guys,

fist post here and have been working out of the country,

Thank you guys so much for all the information and help, I can believe how much support there is!

this is the first i have heard of the 3.3L and I believe this is the way I am going to go.

I defined my plans and have begun ripping out ALL the old harness and wiring a Haltech Nexus R3 and PD16, im running the entire car off both of these units with new wires, once Im happy with the wiring I am moving to the engine rebuilding phase with a stock bottom end and 3.3 cylinders, a bit more cam as well (have not decided which cam to go with, looking at the DC-40)

[Odin911]

For a torquey street rod, a good piston and cam combo would typically feature a slightly lower compression ratio (around 9.5:1 to 10.5:1) for better drivability, paired with a cam that has a moderate duration and lift to provide strong low-end torque without sacrificing streetability. A cam in the range of 220-230° at 0.050" would be a good starting point.