1973 2.4S

The place to post image of your PORSCHES

Moderator: Bootsy

Lightweight_911
Nurse, I think I need some assistance
Posts: 16794
Joined: Wed Nov 12, 2003 10:48 pm
Location: Worcs/W Mids border

Re: 1973 2.4S

Post by Lightweight_911 »

Sounds like a great spec James.

What made you go with crankfire ignition rather than twin-plug distributor - cost, potential reliability, tuneability, or something else ?
Andy

“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
User avatar
hot66
Moderator
Posts: 18221
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: 1973 2.4S

Post by hot66 »

decided on crank fire for a number of reasons ... I will admit cost was a major factor, but also performance ( as in the stability / reliability of timing / spark).

I didn't choose the fully mappable option, but the unit I have gone with is 3 stage tunable & delivers a rock steady advance & timing stability. Very pleased with it so far. Just waiting for a tach signal booster to arrive so I can run my original tacho.

It is a very nice compact system & if I fitted a dummy dizzy in place it would be difficult to tell anything was different from stock ;)
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
User avatar
hot66
Moderator
Posts: 18221
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: 1973 2.4S

Post by hot66 »

a few photos from the dyno sessions

a little bit of high octane for one of the runs ... actually went through a lot more !

Image

ready to go

Image

Image

The control centre

Image
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
964RS
Nurse, I think I need some assistance
Posts: 6489
Joined: Sun Sep 02, 2007 9:53 pm
Location: Midlands
Contact:

Re: 1973 2.4S

Post by 964RS »

Mick Cliff wrote:This does not bode well for the lead car on Northern runs :shock:
It was always a challenge to keep up with James with the engine in its' previous iteration :roll:
That was only because the car behind could not see or breathe because of the smoke Mick! :lol:

Oh and the driver doesn't stop at traffic lights, junctions or roundabouts for the rest to see which way he went :lol:

I'll not mention the off roading :evil:

Sounds like a cracking engine James, hope it stays strong, enjoy :)
----------------------------------------------------
Jason
https://www.SweepingHand.co.uk
Rolex & Omega Watch Purchases & Sales

Image
Mick Cliff
I need to get out more!
Posts: 3277
Joined: Mon Apr 26, 2004 7:51 am
Location: Selby

Re: 1973 2.4S

Post by Mick Cliff »

964RS wrote:That was only because the car behind could not see or breathe because of the smoke Mick! :lol:
Now you mention it Jason, that's almost true :lol: If I recall correctly it was the streaming eyes from the unburned fuel emanating from James' car that always got me!
Merc B Class diesel
Porsche-less
User avatar
hot66
Moderator
Posts: 18221
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: 1973 2.4S

Post by hot66 »

Don't worry, fuel is now being used properly ;)

Here is the dyno plot

Image

As you can see, power really comes in around 4500 rpm , but the torque plot is flat'ish through the whole rev range. It is a major improvement in torque 8)


Image
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
User avatar
Darren65
Nurse, I think I need some assistance
Posts: 7864
Joined: Mon Dec 13, 2010 10:55 pm
Location: North Wiltshire
Contact:

Re: 1973 2.4S

Post by Darren65 »

Sounds awesome James - way over my head and to me the spec was like reading from a Russian textbook :?........but I know I want one! 8)

One very cool car - enjoy :cheers:
ross.mcw
DDK slapper chatter
Posts: 300
Joined: Mon Sep 17, 2007 12:10 pm
Location: Cheshire, UK

Re: 1973 2.4S

Post by ross.mcw »

Lol, which I'd seen this thread earlier - lots of info here that would have helped me over the last few months with my engine rebuild decisions.

The new engine sounds great James!
1972 911T in metallic Gemini Blue
MdR
Moderator
Posts: 2089
Joined: Tue Nov 11, 2003 4:19 pm
Location: East Preston, West Sussex

Re: 1973 2.4S

Post by MdR »

hot66 wrote:Just waiting for a tach signal booster to arrive so I can run my original tacho.
:cheers:
Martin Rogers
+44 (0)7812 167547
'69 Ossi blue warmrod 3.0 911T
[sold & sorely missed]'67S '70 Targa T '75 914/4 x 2
ims101
I luv DDK!
Posts: 994
Joined: Mon Sep 13, 2010 3:24 pm
Location: Nottingham

Re: 1973 2.4S

Post by ims101 »

Come on James spill the beans on your Centre Gravity day out??
Ian
356 Replica with 911sc
Rita the Queen of Speed!
Bertroex
DDK 1st, 2nd and 3rd for me!
Posts: 2048
Joined: Sat May 07, 2005 11:52 am
Location: Brewood, Staffs

Re: 1973 2.4S

Post by Bertroex »

Man, that is an awesome spec. Best people in the business used for each component.... Well done James- this is a about as good as it gets, but... does it have an LSD?

;)

Bert
-1968 912 SWB Targa LHD
-1976 911 Carrera 3.o Targa RHD
-1983 944 190bhp (augment automotive enhanced) RHD
-1979 280SLC manual LHD, 1989 500SL, 1997 SL500, 1989 Jag XJ-s 3.6, old BMW’s
-Ex 1976 911 2.7 Targa, 1979 911 SC, 1983 930,1993 964 C4 Jubi etc
User avatar
hot66
Moderator
Posts: 18221
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: 1973 2.4S

Post by hot66 »

:)

Imagecentergravity by hot 66, on Flickr

With some miles under its belt , the engine is pulling stronger & stronger and definitely feels gruntier than a few 1000 miles ago.... but having had all the suspension apart the handling was crap . We had done a basic alignment etc , but it just felt unstable at speed & unpredictable. I'd even got to the point in wondering what the point of having a quick motor in the back was & maybe I'd gotten too used to the handling of my Turbo .

So I took the decision to get things looked at properly .

Following on from recommendations by other DDK'ers I booked teh car in with Chris @ Centre of Gravity ( http://www.centergravity.co.uk/ )

After travelling down from North Yorkshire the previous night, in some of the worst condtions I've experienced on the A1 & feeling pretty despondent about my car , I turned up @ Chris's yesterday morning ready for him to condem my suspension .

You might have read elsewhere about how the day goes at Chris's, but basically he jumps in the car and 'test' drives it to see how it performs on his test route .. looking for things like the way it pulls, does it change direction on or off the throttle , can it cope at speed on bumpy b-roads etc etc . A few things showed up and I also explined the issues I was having with the cars handling & what I was wanting .

The car was then brought back to the workshop to be looked at.

1st test was a niffty little machine that oscillates each wheel to measure the effectiveness of each damper ( mine were all perfect as expected from new / nearly new bilsteins)

As I only drive the car quickly when I'm by myself , we decided to set up the car assuming just me in it, so my matching weight was placed on the drivers seat . Then up on the ramps for measurements etc . Although geometry was massively off , things were not perfect & my corner weights were way off.

With suspension , change one thing & something else changes as a result ... so although relatively straight forward, it took chris quite a bit of time adjusting , checking , re adjusting etc including reindexing my rear torsion bars to get to a point where he was happy :)

As it turned out, Chris was really happy as he got the cross axle weights spot on & all the geo perfect too. Car was set lower than stock.

Image



So , I got there at 8.35 & left at 20:15 !!! It was a long day :shock: :)

End result ... my car has been transformed 8) I am REALLY pleased. In the twisties it is sharp & secure & I can attack teh corners with confidence .. on the A roads / motorways I can now travel at speed ... for the 1st time ever in nearly 10 years of ownership, ( on a private track ) I can comfortably take the car to some significant speeds and sit there feeling safe.


Chris is very thorough and has a great eye for detail . Really recommended :) My Turbo will be going to him when the time comes.

Couple of interesting points:

I have had my elephant racing bushes on the car for over 6 years & approx 15K miles ... and they still looked as good as new :)

Car's weight , including 80Kg ballast, some spare parts etc , 6 litres of oil in cans + approx 50 litres of fuel = 1212Kg!!!! Calculating back, my car is approx 1110Kg with half a tank of fuel, no driver & with my spares taken out ( guessing 5 Kg of spare parts , 6 kg spare oil, 10 kg extra fuel above 1/2 tank)

Not quite sure how Porsche calculated their weight figures, but its meant to be 1080Kg. . Looks like I need to replace those extremely heavy recaros with something a bit lighter :roll:
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
Mick Cliff
I need to get out more!
Posts: 3277
Joined: Mon Apr 26, 2004 7:51 am
Location: Selby

Re: 1973 2.4S

Post by Mick Cliff »

Back to square one - always a good place to start from :wink:

Question - why do you carry so much 'spare' oil?
Merc B Class diesel
Porsche-less
User avatar
hot66
Moderator
Posts: 18221
Joined: Tue Nov 11, 2003 4:17 pm
Location: North Yorkshire

Re: 1973 2.4S

Post by hot66 »

oil ... it happens to come in 5lt cans & fits nicely in the smugglers box :lol: .. I also took a 1lt can as I've just changed the oil & wanted to 'fine tune' the oil level once the car had had a good run, which as it was wasn't needed as I'd filled it correctly anyway ...... to be honest, I can't remember the last time I actually added any oil when out on a road trip so shouldn't really carry so much ... but like any good scout .. be prepared ;)
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder
1973 MGB Roadster

Its not how fast you go, but how you go fast ;)
Lightweight_911
Nurse, I think I need some assistance
Posts: 16794
Joined: Wed Nov 12, 2003 10:48 pm
Location: Worcs/W Mids border

Re: 1973 2.4S

Post by Lightweight_911 »

Good to hear some first-hand opinions from a long-term owner after a session at CG - I'll maybe try & 'bend your ear' for some more info at Hedingham.

Regarding the car's weight, Porsche quote 1075 Kg (dry) for a '73S - probably virtually no fuel, std (non-sport) seats & possibly without a spare wheel, etc so I would say your car is about right.
Andy

“Adding power makes you faster on the straights;
- subtracting weight makes you faster everywhere”
Post Reply