Improving torque on 82 911sc

[ybn533]

Hi,

my car is a 82 911 with only 67,000 miles and the only problem that I'm aware of is cold start issues (starts on the second kick) and low idle until warm up. so I don't think that the problem is from there or there is any problem at all. the rpm goes up without spots but to feel the car you need to be above 4000 rpm.

what can improve the torque between 2000-4000rpm?

ordered new plugs, wires, Distributor Cap and Ignition Rotor.

what do you recommend for the low rpm power improvement?

thanks
Yaron

[Tippy]

"Free" torque is in timing. Check to make sure it's within spec. If retarded, torque will suffer.

[5String43]

What you describe - not a lot of torque below 4000 rpm - is exactly the way my car is. I think that's the way they are. You just have to adjust your driving style, I should think, to deal with this. Also, I should think that the faster you spin these engines, the more cooling air the fan can pump through the engine.

[Josh D]

Is your car a US or RoW spec? As others have mentioned, proper tune and timing. Next would be the SSI heat exchangers and a 2 in/1 out muffler.

These over square, short stroke, short rod motors are "peaky" by design.

[Joeaksa]

Agree with Josh, SSI heat exchangers and a good muffler will make the car feel like its got 20 hp more and extra torque as well.

Otherwise put a 3.6 engine in the car like I did and you will have all the torque needed!

[Bob Kontak]

My 81 pulls very strong in lower RPMs (stock). Also, when the SC 3.0 model came out, the low end torque was what journalists raved about.

Timing as Tippy says is important. I'm pretty sure vacuum advance is also critical for lower RPM's.

I don't think you have a vacuum retard port on your car but if you do you can see it in the link below. Pull the distributor cap and vacuum advance port and fit another hose on the vacuum advance port and suck on it. The insides of the distributor (rotor) should move some indicating the vacuum advance is working. I will go out on my car and confirm that this is possible right now.

Edit - Just did this and you must pull the rotor and the dust cap and you will see the large diameter stator ring move some when you suck on the hose. If this does not work then your timing will be retarded and as Tippy says, torque will suffer.

Here are the advance and retard ports. The advance is on the left.

'82 911SC Distributor Vacuum Line Connection Question

[Halm]

Don't you adjust torque with cam timing, not ignition timing?

[Tippy]

Both ignition and cam timing affect torque.

[DaddyGlenn]

In these cars, the fun begins at 4,000 rpm. While there are things you can do to broaden the torque curve, your experience is normal.

[FinallyGotOne]

For my 79SC what are some negatives about messing with the timing? I've heard power can increase a bit, but can potentially cause some engine pinging. Also, heard it can cause starting issues. My 79 fires up most times the second i hit the ignition. When I had some various work done on it a few months ago when I picked it up it seemed to have cold start issues where it would crank two to three times before starting. But it's been hot weather here and now it starts immediately.

[Halm]

Originally Posted by DaddyGlenn

In these cars, the fun begins at 4,000 rpm. . .

I must be the contrarian of the day. . I always thought, and have experienced, that the entire point of 964 cams was more power above 4k because standard cams were starting to run out of breath at that point. In other words the fun was over by 4,500 - 5,000 rpm.

[Bob Kontak]

Originally Posted by Halm

Don't you adjust torque with cam timing, not ignition timing?

You could say that for both I think. Cam timing changes the valve/piston location relative to the spark and ignition timing changes the spark relative to the valve/piston location.

I have read where you can advance the SC distributor and use more premium fuel to avoid detonation and get better performance. But I am not saying that is what you should do without some deep reading.

[Bob Kontak]

Originally Posted by DaddyGlenn

In these cars, the fun begins at 4,000 rpm. While there are things you can do to broaden the torque curve, your experience is normal.

They are fun after 4k, surely. Just talking here - Would you say that the SC is flat up to 4k? I have never felt that my 81 is a slouch at lower RPM's.

[DaddyGlenn]

Originally Posted by Bob Kontak

They are fun after 4k, surely. Just talking here - Would you say that the SC is flat up to 4k? I have never felt that my 81 is a slouch at lower RPM's.

Not flat at all. Lets put it this way...I smile up to 4K then grin from there on...

I try to keep the rpms up....I like to grin

[James Brown]

carful with timing, it is real hard to hear detonation and/or preignition on these engines. you can grenade the engine but it will be a fun ride!

[jamesjedi]

- Modify the transmission by adding shorter gears. Very common modification, unfortunately, not inexpensive

- 15 inch wheels can make a noticeable difference

- reduce the weight of the car

[OsoMoore]

Looks like the 4K surge is what they intended. This is from my 79 SC owner's manual.

[DaddyGlenn]

Originally Posted by OsoMoore

Looks like the 4K surge is what they intended. This is from my 79 SC owner's manual.

Anyone have a copy of the same curves for an RoW SC?

[FrinkFrog]

I would agree with "the fun begins at 4000". My SC isn't flat to 4K, but once that's gone by, the last 2,000 are awesome. I don't take it up that high all the time, but if the engine is well warmed up and the curvature of the road demands it, then it's good to exercise the engine once in awhile. I think the power curves on the RPM chart represent what should be expected from a stock engine/transmission SC.

Kirk

[shuzboomer]

It's not a Honda, it's a Porsche the car is made to shift at a higher RPM. I had the same mindset when I first got the car and found myself up-shifting at 2-2500. The car felt and sounded terrible.

One ride along with someone who fixes and drives classic Porsches daily, fixed my wagon.

Step away from the computer and go for a long ride and feel and hear how much better the car runs when you up-tick at 3500-4k.

Good Luck