80 to 83 SC, What's the diff?

[Westy]

I'm learnin' but I'm still a newbe. What are the major differences between the years of the SC's?

Westy.

Lookin' for an SC

[MichiganMat]

The late model SC motor (late '83) had a little bit more ooomf than the others with higher compression(9.8 compared to 8.5:1) and a 3.2 case. Good for about 10Hp I think.

m.

[SC-targa]

US model SC's are generally grouped into two sets. The 78 & 79 models and the 80 through 83 models. The later models had a higher compression 9.3:1, a three way cat with an oxygen sensor, smaller intake ports and runners, better gas mileage, but probably slightly less power. The later model cars usually had a bit more equipment on them.

Early cars had the cam timing retarded for more power, bigger ports and intake runners, a 2 way cat and an air pump for emissions, lower compression (8.5:1?)and potentially less equipment.

In reality, there's not much difference between them. Just buy a good one.

ROW models were slightly updated in 80 with HP now rated at 188 DIN, then upgraded with Higher comression and revised cam timing to 204HP DIN in 1981.

Jerry Kroeger

[Groesbeck Hurricane]

Westy,

Welcome aboard!! There are small differences between '80 and '83 models, but there are almost none between '82 and '83. I would not say you have to stay within a certain year, a well sorted out SC of any year will do you well. Make sure you get a PPI and ask questions. Take photos and post here for opinions. Don't let out your source for the vehicle if everything is feeling good.

Very few of the very first ones you ever look at will actually be "the" car you should get. Look around, spend a couple of months (10 or so should do) and see what is in the market place. Post pictures, go to a PCA or Pelican get together. A well informed buy is better than jumping in feet first to test the water.

[GrindingGears]

It may have been mentioned but, some early '83 cars (like mine 10/82) will have a sump plate at the bottom of the engine. Some of the SCs produced in '83 will not, i.e. they have a 3.2 carrera case.

SCs rule.

[DavidI]

83 was the first year for a cab 911..

David

[Bill Douglas]

Let the car choose you.

Now that must be the most stupid advice I've ever heard.

Look around at a number of cars, choose one that looks in nice condition and is a nice color, then get a good PPI done that includes looking for broken head studs.

[dd74]

There's no great difference between the early SCs and the later ones, unless you're splitting hairs. Early SCs had wider engine intakes. Later ones had higher compression pistons but smaller intakes. The early ones are a bit lighter, but the later ones had somewhat better low and mid range power.

Horsepower and torque are the same for all models (sans smog equipment for the later ones, which sapped 8 horsepower). But you can make that up with driver experience...

They're all good.

[Westy]

You're all helping and I appreciate it. Now if Schuey would only answer my PM's. Take a look at Schuey's '83 SC and tell me what ya'll think. It's a long way to go, but if the car is right, the drive ain't nothin' to lose sleep about. Heck,,,,I've been looking for almost a year, and the stuff I see in So Cal is nothing to write mom about.

[vash]

westy, i love schuey's car! i am going to look at one in concord tomorrow.

[nostatic]

the changes from 80-83 were involved in trying to recapture the sheer magic of the '79 model year. Unfortunately they couldn't quite do it, and things really went downhill in '84...

ducking for cover...

[aigel]

Other things to mention:

The idler arm bases are wider in the later 3.0. That started in 80 or 81. That is very important to have. That idler arm base, in my eyes, is much more important for reliable chain tensioning than the oil fed upgrade. Even if you do the oil fed upgrade to an earlier engine, you must put the wider idler arm! Many oil fed tensioner conversions do not have that.

Nobody mentined the air pumps on the 78-79. Not an elegant setup. A belt and a gizmo under the decklid more to deal with.

Also, the way fuel is supplied at startup was changed in 81. Most of the backfire problems were solved by a metal insert to the air box that distributes extra fuel dumped in on top at start up to the runners better. A popoff valve is still mandatory even on an 81-83, but it's an improvement regardless.

The cams get a bolt in late 81 (this varies) instead of a nut. A superior setup, not in performance, but in ease of maintenance.

If you had equal cars of the entire SC year range, I would recommend you go for an 81-83. They were more mature. A feedback lambda sensor is a much more elegant way to take care of emissions than an air pump. Note that the lambda brain actually gives you the chance to tune the CIS if you use an innovate a/f ratio meter and wideband 02 sensor instead of the stock 02 sensor. You can measure a/f and then send an offset signal to the brain, having it enrich the mixture to optimize for performance! Can't do that on the 78-79.

If nothing else, an 83 SC will be 5 years newer than an 78!

Cheers, George

[JackT]

You cannot go wrong with any of the SC's. There is a group of us that have from 79 to 83 and we take turns making performance changes. They all seam to run about the same with the same modifications. I wouldnt go past the 1983's though. The performance and dependablility really goes down after 1983. One thing we did notice as a difference in modifying the different SC's is that the SSI's heat exchangers seem to give the earlier SC's a little better throttle response than the later SC's.

[bigchillcar]

If nothing else, an 83 SC will be 5 years newer than an 78!

yeah...too bad...but on the bright side, a '74 would be 4 years older than a '78 if you keep looking...
ryan

[Superman]

George is right, and I'm glad he posted. The vastly superior chain wheel carriers (idler arms) are on the later SCs but not the earlier ones. Also, the later SCs have 'hard' injector lines. I like them better. In general the later SCs are "improved" over the earlier ones, albeit subtly. But here's another thing to think about:

The earlier SC fuel system, with the larger intake runners, also have a different sensor plate, fuel distributor, etc. They lack the silly Frequency Valve which is part of the emisisons system, which only impacts idle anyway and has the potential to screw up. So, if you're going to unhook your O2 system (good idea), and particularly if you're going to want better pistons, then the earlier SC (78 and 79) are your best bet. A very slick upgrade is to put higher compression, HI PO pistons in the early SCs (less expensive if you have Nikasil cylinders). Apparently, they go like stink. Early SCs have good bottom end torque, or at least you can make them have very good bottom end torque (mine is very fun to drive as a street car because it has a power band like a V8), but an early SC with the J&E 10:1 piston upgrade will smoke me.

[tsuter]

The earlier SCs (78-79)are better..... if you want to mod it to 300HP!!

[Shuie]

The '78-'79 cars are also better for people who live in states that currently have a 25yr cutoff for emissions testing.

[rpiper]

Lots of good info here. I would go for the 78-79 SC because of the larger ports and CIS runners. They respond better to upgrades than the later SCs, and they're lighter cars overall. On the other hand, Schuey's car is gorgeous. One of the best looking SCs I've ever seen. A good example of any of the years will be a real pleasure to own.

[rpiper]

Sorry couldn't resist:

[Glasgow 911SC]

Originally posted by rpiper
Lots of good info here. I would go for the 78-79 SC because of the larger ports and CIS runners.

I believe the late model (204Hp) Euro models use the early cars' larger intake runners.
81-83 Euro is the king of the SC's