1965 Porsche 911 2.0

[simon drabble]

Out of interest could someone please tell me whether cars are allowed to run Weber's or do they have to run Solex to comply with FIA? Does it make a lot of difference?
Also are 2.0s engine spec allowed to run and if so again what is the difference between this and an L spec?
Why was the podium car excluded from this year's Six Hour?

[terence]

Solex only dear boy,2]Hardley any at all.3] I belive that the "S" engine is perfectly acceptable in 2ltr form,its the 2.7s that are the pain.4] Because of it being something like 45kg underweight.
As far as S and L specs are concerned,I'll leave that to someone who really knows but I always thought it to be compression and cam mostly.Has your leg been on a diet yet?

[simon drabble]

Originally Posted by terence bower

Solex only dear boy,2]Hardley any at all.3] I belive that the "S" engine is perfectly acceptable in 2ltr form,its the 2.7s that are the pain.4] Because of it being something like 45kg underweight.
As far as S and L specs are concerned,I'll leave that to someone who really knows but I always thought it to be compression and cam mostly.Has your leg been on a diet yet?

yes and now I am back on crutches again I have to say I feel like I have gone backwards!! If I knew how to post photo's I would post a smudge of the metalwork to see if any of you technically minded folk could see a mechanical use for it!
Up until a few years ago no one wanted to race 911's as they were considered heavy and slow but now they seem to be having a resurgance.
Is this because of an overlooked breach which will be closed?
Is it feasonable to convert an L spec engine to an S and if so whats the cost or is it easier to start again?

[terence]

The resurgence was recognised months ago by Ivan Dutton,snapping up everything that was cheap around the country [apart from one ]
Going from L to S shouldnt warrant starting again Simon it must only be something like a piston change and cam swop,they do tend to run a fair bit of weight but there is a certain amount to be legally removed.

[simon drabble]

I was thinking even before Ivan Dutton. They are homologated at 817kg I think - which I guess is similar to a B but presumably power should be greater if both legal...

[terence]

That surprise's me Simon,dont know why but I always thought they were heavier,they have an advantage of 31kg under a B.That thing I had advertised is still available but it certainly is not worth what he was asking,there is a problem with either a valve guide or piston rings.The interior paint is not nice,I should have had a look myself rather than take some-elses word on the condition!,I dont think it would be worth half of the original asking price.But saying all of this does'nt mean it would be a bad car [at the right money] it is an "S" and has the right bits on it already.

[simon drabble]

Well we need one-two to give us the definitive answer on weight. I have to say I am always impressed with how well they race as my recollections of my roadcar was that they are terrifying in the wet!

[one-two]

Simon - we run at 1002kg. I think - in very round numbers - we have a 10% power advantage against a B and a 10% weight disadvantage. Means the racing between the two can be very close, though a 911 ought to be the quicker car on a circuit with decent straights. It's solexes only in period F. I think most cars are probably running S-type high compression pistons and cams - though there is quite a wide variety on the latter from the mild to the wild.

[terence]

Well done one two,the B is homologated at 848kg.What power would you expect from a legal "S" engine?

[one-two]

So the weight disadvantage is a little more than I thought - more like 20% than 10%. Explains a lot! The quicker 2 litre cars are around 180hp - hard to get them beyond that etc

[esper]

I think the 911s are developed very well (to well) especially our dutchies(duell) . but one has to admit that the drivers did addapt to those unpleasant cars as well. There are some awsome videos to be seen at youtube. just put 911 and francorchamps and you can see those guys just go sideways all the way. (I am sorry, I dont want to insult anybody with a 911 but my son and I tried to build a similar setup in LEGO and it really doesnt work with that aircooled engine putting all the weight in the back)

[terence]

Originally Posted by one-two

So the weight disadvantage is a little more than I thought - more like 20% than 10%. Explains a lot! The quicker 2 litre cars are around 180hp - hard to get them beyond that etc

So in theory they should be pretty close together after-all.

[simon drabble]

Originally Posted by one-two

So the weight disadvantage is a little more than I thought - more like 20% than 10%. Explains a lot! The quicker 2 litre cars are around 180hp - hard to get them beyond that etc

incredible that they are so iconic yet on paper never goingto set the world alight. 150 kg heavier than an MGB that is two passengers. They run about 120 kg heavier than a Ti Super and only put out about 20 bhp more.. I am really amazed - especially when you see them at Spa they look and sound magnificant.
So they are in fact quite indulgent bang for your buck. This whole thread started because I saw a rally spec one with FIA papers on EBay for sensible money (as opposed to the £60-65k cars I have seen advertised - which is E Type Coupe territory) and it got me thinking.
Like B's they are as tough as old boots and cheap to run but with a big weight disadvantage... Is that why people rally them instead?

[Peter Mallett]

I guess they might also be a bit more aerodynamic than the competition, which at places like Spa is an advantage. The tail-happiness from the weight distribution wouldn't show there as much as (say) Silverstone where there are some rapid direction changes (Maggots/Beckets and Bridge).

So long straights, fast sweeps would perhaps suit them. And again at Spa there are two slow corners where the rear end bias wil provide for more traction.

And of course they were very successful rally cars too.

[esper]

the honnest cars at Spa had some serious money invested. the a960s 911 was already a briliant piece of engineering which cant be said of an MGB and then modern technology in great shockers and engines with todays knowledge.

[Hagis]

Hi!
I´m not an expert on Porsches, but have been in it so much to say that you cannot run 911 S heads if you are going in Period F (-65) as you are limited to the valve sizes 39/35 mm according to Homolog. form 183, and the valve sizes of the 911 S are 42/39 if I remember right, and they are also later than -65. But you can use 911 S pistons and cams; budget bits in this case as oposed to special pistons and Carrera & cams or similar. As said earlier in this thread the weight is (heavy!) 1002 kgs, and you can just use Solexes. However, if you are going to run it as a "G" period car, you can also use Webers, and the weight is down to an "amazing" 999 kg according to Homolog.form 503. But in "G" you could as well build a 911 S with those big valves and also bigger ports from the beginning, remember a 911 S had 160 hp just from the scratch. I don´t know of the weight for an "S" but the homologation paper 547, again if I remember right, will tell. Might be they became less honest and could produce a more "competitive" weight by then.

[FastDB2s]

When I was in Ireland in 1998 -99 we tried all manner of means to beat Dessie Nutt in his 911 (histroric rally), I prepped a Manta A (post historic rally)(the owners knew each other well) & used all the tricks we could suspension wise from one of my Manta 400 set ups, a really stiff shell, good cage in it - as light as we could be legally, corner weighted, etc.
We had about 180bhp - 4 speed cr sc box & a couple of diff ratios.
We succeeded once - we didn't beat it - we just got it to break.
At the time it was rumoured that the gear ratios were the key, plenty of them - all homologated.
those + Fran Tuthill prep on the car & Dessie's driving - unbeatable combo

[simon drabble]

an interesting point - the cars have been used more for rallying than racing where of course weight is not so much of an issue. There is no getting away from the fact that they are 150 kg over an MGB...