ENGINE GURUS! Help Me Compare A Stock SC Motor To....
 

Doing a little research for an upcoming video.

I don't know engines REALLY well, so I'm curious how these specs differ from a stock SC 3.0 engine:

6 Cylinder, 2999cc boxer engine
4-valve, quad camshaft
aluminium cylinder heads
Open-deck aluminium cylinder block
Bore: 89.2mm
Stroke: 80mm
Rod Length: 131.5mm
10.7: Compression ratio
Dual timing chain system
Coil on plug-ignition system
Plastic intake manifold
Drive-by wire electronic throttle body
76mm OD3 exhaust-port cylinder head design
Variable lift and variable timing intake camshaft (ALVS and AVCS) much like Honda’s iVtec system.

Can you help me identify the differences, and/or point me towards a similar spec sheet for the 3.0 SC engine?

Thanks!

I'll take my best shot. Others can add or correct if I got something wrong.

6 Cylinder, 2999cc boxer engine <-- SC is a 6-cylinder boxer 3.0L
4-valve, quad camshaft <-- SC is 2-valves per cylinder & 2 camshafts
aluminium cylinder heads <-- pretty sure this is true for the SC
Open-deck aluminium cylinder block <-- ???
Bore: 89.2mm <-- 3.54 in/90 mm
Stroke: 80mm <-- 2.77 in/70.4 mm
Rod Length: 131.5mm <-- ???
10.7: Compression ratio <-- I think US is 8.5:1? and Euro version is 9.3:1
Dual timing chain system <-- two chains
Coil on plug-ignition system.<-- SC uses captive discharge ignition, single coil and distributor to fire all cylinders
Plastic intake manifold <-- um, almost everything is these days?
Drive-by wire electronic throttle body <-- CIS fuel injection has throttle plate
76mm OD3 exhaust-port cylinder head design <-- ???
Variable lift and variable timing intake camshaft (ALVS and AVCS) much like Honda’s iVtec system. <-- no variable camshaft, cam profile is what it is

One of the main differences you didn't mention sounds like your other car uses EFI and the SC used CIS.

Literally Everything I needed. Thanks Tim.

Sure, no problem. Go back and look at my post again. I made a mistake and corrected it.

Open-deck aluminium cylinder block < Pretty sure this is describing the water jacket design on a water cooler engine.

Open Deck
https://dsportmag.com/wp-content/upl...1-OpenDeck.jpg

Closed Deck
https://dsportmag.com/wp-content/upl...ClosedDeck.jpg

SC rod length is 127.8mm
SC CIS has aluminum intake tubes and a plastic plenum.
SC is air cooled, so the cylinders have fins, not open or closed deck as with liquid cooled engines.

3.0 is 95mm bore
127mm rod length
The rest looks good
Tony

subaru ez30-ii?

What you list is not an SC 3.0, more like a more modern water cooled Boxter
Bruce

We haaaaaave a winnerrrrrrr

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One thing I didn't ask, but it's worth knowing: SC engine 462lbs, Subaru EZ30 397 lbs.

And for EZ30 you have power output of:

180 kW
240 hp; 240 PS
@ 6,600 RPM[21][33]

297 N⋅m
219 lb⋅ft
@ 4,200 RPM[33][34]

If you boost it then typical limitations are about 340Hp.

https://www.possumbournemotorsport.com/ez30-info

Boosted 3.0 911SC could be above 500hp. Each requires money and skill to build for high power and address weak points and cooling.


I looked into this for my old Suby powered 914.

And then the weight is offset by the cooling system and coolant. But the distribution of weight can be favorable depending on locations and mounting points.

Specs say it takes a gallon of coolant, or 8 lbs. and about 5 less quarts of oil than a Porsche. So it’s a wash.


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I think he was talking about the radiator and hoses. I don't suppose those weigh more than 20 or 30 lbs?

Looks like fun.

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I didn’t realize it was an advert , I thought it was a technical question

It is. What am I supposed to be selling?

Even then...a wash with an external oil cooler, which I have in my other car.

Either way, should be fun indeed!

Early SCs CR was 8.5:1. Later US 9.3, Euro 9.8.

4 valve water cooled engines with knock sensors and ECUs seem able to run a point or so higher on the same octane fuel.

There are nominally stock SCs out there which appear to put out 240 flywheel HP (estimated from RWHP figures, as not many shops have an engine dyno). How is a good question.

Kudos to you. Can’t wait to hear how this drives.