A few questions on handling improvements on a 79SC.

[MaxzmusSC]

Hi Guys,

 

New to the board and just picked up a neat little 79SC recently.

 

Have a few quick questions around handling improvements.

 

1. What's the consensus on sway bar combination front and rear. Also where best to source them?

 

2. Where to source 3 point front struct brace?

 

3. Any recommendations on track grade engine and gear box mounts?

 

Am in the process of acquiring a Bentley manual so excuse the silly questions from me.

 

Hope to meet/chat with all of you in the future....

 

 

Cheers,

William.

[Doish13]

Nice looking SC mate - you've come to the tight place with those questions, plenty of knowledge about.

Bentley Manual?

[tazzieman]

I thought all Bentley's were automatic?

The SC handles pretty damn well unless you are pushing hard on a track. Tyres first. Then other stuff. How harsh a ride do you want? You might need stiffer torsion bars whilst the credit card's out buying A arm bushings and monoballs.

[clutch-monkey]

lower it a touch/slightly thicker torsion bars rear/simple strut brace up front would be my pick for a useable street combo

[tazzieman]

If you are after track grade , Wevo mounts , solid or semisolid .

[MaxzmusSC]

Oh I thought these were common? I had them for my M3 and VW's in the past.

 

http://www.ebay.com/itm/Bentley-Service-Repair-Manual-for-Porsche-911SC-78-83-/280954632718

 

Thanks for the link Tazz.

 

I"m use to having my cars very rigid and rock solid for better feedback and chassis responsiveness.

 

Ah funny....I was looking at torsion bars and still ended up calling them sway bars. Oops. 

[tazzieman]

Oh I thought these were common? I had them for my M3 and VW's in the past.

 

http://www.ebay.com/itm/Bentley-Service-Repair-Manual-for-Porsche-911SC-78-83-/280954632718

 

 

I was having a laff! I've got my Bentley with manual trans! You need the bible if you work on these cars.

[clutch-monkey]

Oh I thought these were common? I had them for my M3 and VW's in the past.

 

http://www.ebay.com/itm/Bentley-Service-Repair-Manual-for-Porsche-911SC-78-83-/280954632718

 

Thanks for the link Tazz.

 

I"m use to having my cars very rigid and rock solid for better feedback and chassis responsiveness.

 

Ah funny....I was looking at torsion bars and still ended up calling them sway bars. Oops. 

consider adding the early style sway bar that runs behind the fuel tank as well then!

[MaxzmusSC]

I was having a laff! I've got my Bentley with manual trans! You need the bible if you work on these cars.

 now I'm worried. Which manual do you guys use?

[Stardust]

This is up my alley. I have a 78SC (77 build - so very early model).

 

Here's what I've got. And it all works very, very well on track, tarmac rally, and road (but I don't mind a hard ride on the street - it's the handling that is important to me):

 

1. A very good mechanic

2. Wevo semi-solid engine and trans mounts

3. Through the body adjustable front sway bars (22mm)

4. Adjustable rear sway bar (22mm - both front and rear are Tarrett-type)

5. Hollow torsion bars (22mm front 30mm rear)

6. Reinforced rear torsion bar mount to handle the upgraded bars - it will crack otherwise

6. Carbon fibre strut brace - not three point but does the job

 

Here's what I don't have:

 

1. Dampers to handle all of this. Currently my Bilsteins are knackered and need rebuilding. If you do all of the above, I would suggest a custom revalve job for the dampers to accommodate the change in sway bar/ torsion bar/ intended use

2. As per tazzieman I'm slowly upgrading all my bushings

 

While we are talking "handling" it looks like you also have 7&8x16 Fuchs? I have 225 and 245 Toyo R888's on mine. These do the work/school/track day duties and work a treat. Just be careful in the wet.

 

Hope this helps. Cheers.

 

Oh, I wanted to add that one of the fastest SCs at the Porsche Club NSW sprints is running, in his own words, "very soft settings". So I guess it also depends on how you drive but something like the setup above should give you a solid enough base to enable tweaks (add double adjustable Konis if you have the moulah )

[tazzieman]

 now I'm worried. Which manual do you guys use?

http://www.ebay.com/itm/Bentley-Service-Repair-Manual-for-Porsche-911SC-78-83-/280954632718  is the right one!

That and the little 911sc factory specs booklet , and the 101 projects book. And the favourite? http://www.amazon.com/Porsche-911-Performance-Handbook-1963-1998/dp/0760331804  Indirectly it's got the potential to be a very expensive book 

 

As an aside , I'm beginning to believe a harsh street ride is a result of the harsh streets, the worst around here are the old concrete trolley bus roads and the main road through the heart of Hobart - the lumpiest and bumpiest ride you'll ever get. 

Roads are continually being dug up for NBN and routine infrastructure. It's a mess. But I still cant warm to a Jag or Bentley yet! Other than the paper version.

[Simonoz]

This what I've learnt. Hope it helps.

It's pointless trying to stiffen a torsion bar car too much. Law of diminishing returns applies.

So,

Check and if required replace all wear parts first. Bearings bushes etc with quality bits. There are numerous suppliers.

Use top quality tyres.

Get some top quality shocks in there early. You can have them revalved later if you start to beef up.

Learn how to drive the thing before you start to modify it.

If you've got it well set up as a basically standard car you will be amazed at how it will out drive you.

When you are out driving it, start the modifying process.

By the. You will probably have the it h for a different 911 and be really glad you haven't turned yours into a money pit.

And you'll be a much better driver ready for whichever direction you choose to take.

And I should also add, don't put a 3 way strut bar in a street car. If you prang it it will derange your front tub much more than a simple strut brace.

All the best.

[Stardust]

Corner balance, corner balance, and corner balance

[clutch-monkey]

This is up my alley. I have a 78SC (77 build - so very early model).

 

Here's what I've got. And it all works very, very well on track, tarmac rally, and road (but I don't mind a hard ride on the street - it's the handling that is important to me):

 

1. A very good mechanic

2. Wevo semi-solid engine and trans mounts

3. Through the body adjustable front sway bars (22mm)

4. Adjustable rear sway bar (22mm - both front and rear are Tarrett-type)

5. Hollow torsion bars (22mm front 30mm rear)

6. Reinforced rear torsion bar mount to handle the upgraded bars - it will crack otherwise

6. Carbon fibre strut brace - not three point but does the job

 

Here's what I don't have:

 

1. Dampers to handle all of this. Currently my Bilsteins are knackered and need rebuilding. If you do all of the above, I would suggest a custom revalve job for the dampers to accommodate the change in sway bar/ torsion bar/ intended use

2. As per tazzieman I'm slowly upgrading all my bushings

 

stardust is spot on!

i've got exactly this except the early type through the body front sway bar (that's next!)

i agree with simonoz, the three point front strut brace is not the best.

wider wheels and tyres will give more lateral grip but can sometimes detract from steering and handling feel.

 

[MaxzmusSC]

This is up my alley. I have a 78SC (77 build - so very early model).

 

Here's what I've got. And it all works very, very well on track, tarmac rally, and road (but I don't mind a hard ride on the street - it's the handling that is important to me):

 

1. A very good mechanic

2. Wevo semi-solid engine and trans mounts

3. Through the body adjustable front sway bars (22mm)

4. Adjustable rear sway bar (22mm - both front and rear are Tarrett-type)

5. Hollow torsion bars (22mm front 30mm rear)

6. Reinforced rear torsion bar mount to handle the upgraded bars - it will crack otherwise

6. Carbon fibre strut brace - not three point but does the job

 

Here's what I don't have:

 

1. Dampers to handle all of this. Currently my Bilsteins are knackered and need rebuilding. If you do all of the above, I would suggest a custom revalve job for the dampers to accommodate the change in sway bar/ torsion bar/ intended use

2. As per tazzieman I'm slowly upgrading all my bushings

 

While we are talking "handling" it looks like you also have 7&8x16 Fuchs? I have 225 and 245 Toyo R888's on mine. These do the work/school/track day duties and work a treat. Just be careful in the wet.

 

Hope this helps. Cheers.

 

Oh, I wanted to add that one of the fastest SCs at the Porsche Club NSW sprints is running, in his own words, "very soft settings". So I guess it also depends on how you drive but something like the setup above should give you a solid enough base to enable tweaks (add double adjustable Konis if you have the moulah )

 

Cheers stardust......exactly what I was after, much appreciated. Thanks to the others who have replied as well. Just need the AUD to go back to parity now  .

 

Some quick snaps of today's OP morning drive. I must admit before getting the car I didn't think the base level performance would be this good. Very happy with the rigid chassis and mid corner grip and feel. Still needing to get use to the weight transfer off throttle though.

 

 

 

[Simonoz]

. Still needing to get use to the weight transfer off throttle though.

 

Thats the fun part! You can dial some of that out just by lowering your ride height.

Agree with the others that corner balancing and alignment are vital. Suggest you do the bushes etc first, to save time and money. Also you could buy one of the alignment tools offered by one of the PCNSW members. Really handy gadget.

If you can find Tony Drons Porsche book ( the name of which escapes me, the one where he covers his Porsche life only) he mentions the car owned by the Porsche engineer. Tony ran it round the Ring, said it was the best he had ever driven, asked what had been done, and was told nothing. To his surprise, all it was was a standard car in proper condition, aligned and balanced. I have always tried to remember that article when the cheque book comes out twitching at another modification. Doesnt always stop me though!

[PeterP]

Nice car, looks tidy. What front seats are they?

[jnr356]

i'd grab a set of koni's first up

[Harvs11]

I totally agree with Simon here. There is so much to gain by just getting the setup right. Before I had my very stock SC aligned properly it was a chore to drive. Heavy steering, massive understeer braking into tight corners and quick transition to oversteer mid corner.

First thing I did was lower the ride height from the taller US settings to Euro spec. Then had the camber/ caster adjusted for a mild track setup. The result was a revelation. Now it turns in easier, with controllable attitude coming out of a corner on the power. The steering is also lighter and a pleasure to drive. Combined with EBC yellow track day pads and good tyres it hasn't cost me a fortune as I didnt need to replace any of the factory suspension.

My advice is to get it set right first before spending on suspension mods.

There's a lot of fun in these old cars straight out of the box.

[9fan]

First thing I did was lower the ride height from the taller US settings to Euro spec. Then had the camber/ caster adjusted for a mild track setup. The result was a revelation. Now it turns in easier, with controllable attitude coming out of a corner on the power. The steering is also lighter and a pleasure to drive. Combined with EBC yellow track day pads and good tyres it hasn't cost me a fortune as I didnt need to replace any of the factory suspension.
My advice is to get it set right first before spending on suspension mods. 
There's a lot of fun in these old cars straight out of the box. 

 

Good advice guy's, This is a basis of good setup for any car.

Just remember a good race fluid when you put the bettter pads in and braided brake lines -huge difference in being able to stop !

[sydr]

it 'looks' like you have turbo wheels - great first step.  Go 16" turbo fuchs wheels, 7" front, 9" rear. Do not use el cheapo wheels unless you are ok with sudden unhappiness.  Street legal 'dot' tyres, take your pick of brand.  I like Kumho because they warn you before letting go, others may be more violent in their transition from grip to goodbye. Fit Turbo tie rod ends and a simple strut brace.  Transformational.  Lower the car and put some forward tilt on it. Decent shocks.  Once you find that you are driving so hard on track that the brakes are smokin' then you may have to make a change.

Then consider whether to spend some money on the driver.

 

Go for the paper Bentley manual, the other option is expensive. 

 

 

[tazzieman]

 

 

“There’s a huge amount of old cock talked about the handling of old air-cooled 911s…”

 said James May!

[MaxzmusSC]

Nice car, looks tidy. What front seats are they?

 

They are some sparco seats that came with the car. I have the original seats still which I may look to seal in the near future. I haven't really decided as yet.

 

Thanks Simonoz for your comments, I think you make a valid point about the stock handling potential of these cars. I've tracked many FR cars in the past and am now building the skills up for this platform.

[Simonoz]

Thanks MaxzmusSC. Appreciate your comments.

I just read Syds comments above re 16inch wheels.

I dont disagree with him, but would like to relate a story about my rather stout 1975 911 that I handed to its new owner on Thursday last week.

We (he and I) drove it prior to handover withe the car on the Simmons 16" wheels I ran it on when road use was required.

It was delightful as always, and we agreed terms, both happy.

I put the 15" Fuchs back on it at his request, drove it again, realised it was much quicker in a straight line courtesy of the gearing change, loved it, called him to let him know it was way quicker and to be careful (its been wet here in WA), and put the car into storage.

He drove it the next day and let me know that it certainly was quicker, to the point of exclamation.

He was right, it was very much quicker.

My point is this.

On the short circuit at Barbagallo, use 15" wheels.

On the long circuit, use 16" wheels.

Same rubber, different gearing,

Horses for courses.

The street is one thing, the track is another, and each track is different.

If you're going to concentrate on track use, thats one objective.

And its really the best of fun when you knock off a much modified car with your standard(ish) car.

Your SC is a very nice example.

It will be fun to see wht you do with it.

Rgds

Simon

(back to one 911 and hunting for another)

[sydr]

Thanks MaxzmusSC. Appreciate your comments.

I just read Syds comments above re 16inch wheels.

I dont disagree with him, but would like to relate a story about my rather stout 1975 911 that I handed to its new owner on Thursday last week.

We (he and I) drove it prior to handover withe the car on the Simmons 16" wheels I ran it on when road use was required.

It was delightful as always, and we agreed terms, both happy.

I put the 15" Fuchs back on it at his request, drove it again, realised it was much quicker in a straight line courtesy of the gearing change, loved it, called him to let him know it was way quicker and to be careful (its been wet here in WA), and put the car into storage.

He drove it the next day and let me know that it certainly was quicker, to the point of exclamation.

He was right, it was very much quicker.

My point is this.

On the short circuit at Barbagallo, use 15" wheels.

On the long circuit, use 16" wheels.

Same rubber, different gearing,

Horses for courses.

 

 

Simon is right, of course.  When you go to 16" wheels, I assumed that it was obvious to select a lower aspect ratio so that the overall wheel height with the bigger wheel/lower rubber is similar.  Hence, your gearing remains basically the same but your handling becomes more responsive by virtue of the lower sidewall/less flex. 

 

Sorry, I assumed that this would be obvious