start with a 911 carrera or 911 SC???

[newcar08]

trying to decide between these two models and need to weigh the +'s and -'s.

is it easier to make up for the extra weight of the carrera or the weaker engine of the sc?

as far as i can tell the main differences between the sc and the carrera are about 400lbs and 30-40hp (ignoring the g-50 vs 915 debate).

my car will be lightly modified and see both track and street either way (at least to and from the track) I am hoping the veterans here can advise which build will be better/more cost effective in the long run. Some of the weight savings threads post numbers in the 400-500lb range (carreras) which seems to make up for the difference, but what are you giving up that an sc still has? also that makes any weight-saving possibilities on the sc look even better (does anyone know what more is to be had there?). I am hoping to get 250 - 300 whp at the end of the day and this may be significantly easier in the carrera from an engine standpoint.

i like light quick cars formerly having owned a lotus elan i am hoping to build a pretty light car but with significantly more power and suspension/brakes to match.

fyi- yes i have driven both 911 and sc I am asking more from a mechanical/technical perspective of what can be done and how much it costs

[Jack Olsen]

Have you worked out how you're going to get 250-300 whp out of either of those motors? The cost of doing that will certainly dwarf the cost of the rest of the project.

My advice would be to either buy a completed project with the specs you're looking for, or mix and match an already-built engine with a light-as-you-want chassis.

[Dave at Pelican Parts]

I believe that a 3.2 makes a better daily driver than an SC. The DME and the taller gearing combine to give better fuel economy, and the 3.2 just seems more "relaxed" driving around normally than the 3.0 does (so far).

If you're doing major engine upgrades and keeping the stock gearing, the SC is the better starting point because of the slightly lighter weight and the shorter gears. (I'm not sure why you would want to change the engine and not the trans, but...)

If you're doing "everything", I don't think it really matters that much which one you start with.

--DD

[Astroman]

The SC is just about as potent at the track due to its lighter weight, some would argue more. But I would rather drive a Carrera to and from the track... the newer cars might be a little more reliable... and a little easier as a "daily driver"...

But if you're considering adding a lot of horsepower, you may want to go with an '87-'89 G50 car...

[sscates]

More street = Carrera
More track = SC

With the track, I would go with the lightest car (sc). You could always put a 3.2 or 3.6 as Jack was mentioning, but getting the weight down is always a challenge. I would assume that you could make a carrera the same weight as the sc with a little effort. Don't think you could make either as light as the long hoods though. If my memory serves me right the last two cars to win the POC GT-2 (normally aspirated, unlimited) were both early 70 models with 4.0 powerplants.

Have fun!!

[Noel]

Both cars are good starting points and both share many of the same suspension parts. I've been tracking mine for 7 sessions and it has been extremly reliable. THe thing to remember is that the better it is on the track, the worse it is on the street.

Good luck.

[pgeorgeson]

Are SC's really 400 pounds lighter than Carreras? I find the surprising. Does anyone have the listed weights of the stock cars?

[sscates]

That is a bit much, I would think 150 or something. I can't imagine Porsche trying to explain that with a new car launch. "Oh yeah, and it's only 400# heavier than our previous model".

[pgeorgeson]

To answer my own question (maybe), the PCA Club Racing Rules have the following weights and hp figures:

78-83 911SC: 2702# 180 hp 15.01#/hp
84-86 911 Carrera: 2812# 207 hp 13.58#/hp
87-89 911 Carrera: 2906# 217 hp 13.39#/hp

[juanbenae]

Originally Posted by Noel

THe thing to remember is that the better it is on the track, the worse it is on the street.

forced me to get a subaru and finish the job by ripping the interior out of the 911 and cage it. http://forums.pelicanparts.com/california-southwest-us-az-nv/443725-plunge.html#post4330330

t

[glewis80SC]

Originally Posted by Jack Olsen

Have you worked out how you're going to get 250-300 whp out of either of those motors? The cost of doing that will certainly dwarf the cost of the rest of the project.

My advice would be to either buy a completed project with the specs you're looking for, or mix and match an already-built engine with a light-as-you-want chassis.

+1, getting that much HP will not be cheap, it is possible but maybe not cost effective. The SC is a GREAT little car, i track mine and use as a daily driver, very reliable and a blast on the track, i've done the t-bars to 22/28, adjustable sways and bilstein sports. The ride is stiff but not tooth rattling stiff, the SC still has that go cart feel to it.

[earlyapex]

I would start with a SC. They are inexpensive and weigh less than a later car. Here is my 78. As you can see allot has been done to it. I still have the 3L motor in it. The motor is very mildly tuned and puts out 211 hp at the wheels. You can get more out of the motor as long as you have the money. How much do you want to spend and what are your end points. I highly recommend deciding on your end point as this will dictate where and how much you spend. For racing, this means what club you will race with and what class you want to compete in.

[newcar08]

the endpoint i had in mind was hopefully less than 2500#'s and roughly 250 whp (lowering my expectations now... ) in a car that is still street worthy and presentable (not a track only stripper) with most of the work done by me hopefully

the weight savings i'm not too worried about anymore seeing threads of people pulling out 400+ from the porkers and not looking too gutted for my taste.

any idea on parts/price to get more out of the 3.2? i could have sworn i saw people getting 200+ from 2.7's at one point so this really shouldn't be too hard.

[earlyapex]

Getting 250 rear wheel hp out of a 3.0 liter SC motor is going to be expensive. I can't speak for 3.2 liter motor, but any time you open up a Porsche motor you will hear a sucking noise from your wallet. Parts have gotten very expensive. Labor is about $120/hr at a local race shop in San Jose that is well respected. I post this as a reference point. Lightening a car is far less expensive and will improve all aspects of performance. This is where you should start. My car started out as a stock 78 SC that I drove on the street. I've driven it through multiple versions so I can speak for what each modification has done. Losing weight is by far the biggest bang for the buck. I then recommend spending money on a good suspension. The stock brake system needs only a few modifications to make it reliable for the track. The engine is the last place to sink you money.

[Mahler9th]

Don't forget to check in with local resources... those with racing pedigrees. The internet is great, but not all answers are equal... I always suggest resources with good reputations in the PCA, like those we have here in Norcal to whom Eric referred. The engine builder at that resource was 1977 IMSA mechanic of the year and has a pedigree that... well you get the idea.

The best to start with is your endpoint from a dollar versus performance standpoint. Someone is selling your endpoint, having spent much money and time so you don't have to. That is almost always the best approach unless you want/need a project...

For example, a few years back, some local folks I know built a car like what you generally described as your spec... but since they were able to leverage local resources, their initial investments were, well, leveraged. Tub came from a well-known dealer mechanic/PCA Tech committee member/"shoe"... he had it just sitting around. Motor was a 3.5L made from a 3.2 case, and ran chipped motronic, built my a reknowned Reno-area builder. All the basic stuff for fun on the street, AX, track and what have you.

A few years later they took it endurance racing. Some mods from Wevo and SRP and some clever engineering: 25 hour winner and twice runner-up in three total tries. Was even on TV. That car was sold this year for a fraction of what was invested...

For a light weight car, I'd always start with a 78 or older. No real competition.

[htron435]

I was just browsing the classifieds -- someone is selling a '74 with a 3.6. There's your target weight & horsepower, ready to drive home. I bought my 81 SC 3.6 already built for about 1/3 of the PO's build cost. And I love it. Torque of a Corvette

[Noel]

Originally Posted by htron435

I was just browsing the classifieds -- someone is selling a '74 with a 3.6. There's your target weight & horsepower, ready to drive home. I bought my 81 SC 3.6 already built for about 1/3 of the PO's build cost. And I love it. Torque of a Corvette

I can vouch for that. I drove Jay's 3.6L at Mid-Ohio a couple years ago and the old girl is way quick...and much cheaper than a GT3.

[PatrickB]

Originally Posted by htron435

I was just browsing the classifieds -- someone is selling a '74 with a 3.6. There's your target weight & horsepower, ready to drive home. I bought my 81 SC 3.6 already built for about 1/3 of the PO's build cost. And I love it. Torque of a Corvette

1974 911S with 993 3.6L engine Track Car for Sale

+1 Jay! This is the friggin' deal of the year right here!!!!! It's basically track prepped for DE's/ POC/PCA Competition as it sits, for only $18.5k? A 3.6, close ratio 915 with LSD, upgraded suspension goodies, 8x9.5x17 wheels, custom welded cage, race seats, harnesses, car lightened to 2400lbs., 270hp ... If you are serious about purchasing a car for the track, the deal doesn't get better than this! This is killin' me! i wish I had an extra $20k layin' around... This and another 2 years of track time, and I bet I might be able to keep up with Jack!

[ZOA NOM]

I would echo Mike's comments above, and add that I am currently racing a 3.2 G50, which I am having trouble getting down to the class weight minimum. I believe I have an advantage with the G50 in terms of shifting and maintenance over the 915. I've seen several motors blown by competitors who missed the 3-4 shift. I'll deal with the extra weight of the tranny. I also notice that I don't have to tinker with the Motronic as much as the other guys have to mess with their ignition/fuel delivery systems. The motronic is pretty robust and the chip changes are simple. The 3.2 has smaller rod bolts, which should be replaced with ARP if you intend to rev the motor very high. This can open up a whole lot of "while you're in there's", adding significant cost.

The stock Carrera brakes work very well for me on the track so far. I have only recently experienced some fade, and most likely due to poor bleeding and pad choice. I have run Pagid Oranges with simple control-arm scoops for cooling without any issues at all, even with the car at it's heaviest. SC brakes will have to be addressed for the track.