2 Litre Engine design origins

[vincematthews]

I thought this was interesting, having always thought the engine was an Audi/VW LT product.
It seems the original design was done by Mercedes and the engine went through various evolutions over many years to become the 924 power plant. We won't talk about the AMC Gremlin [:'(]

http://flussigmagazine.com/11/post/2014/12/origins-of-the-ea831-engine.html

Probably old hat to some?

 

[PaulHere]

Well found, the detail is quite something here.

 

[geoff Ives]

The myth that says that the 924 engine is the same as the VW LT van is just that.
The 924 was a design concept for a new VW sports car that was cancelled and bought back by Porsche. The original design was for a front wheel drive car and that idea was scrapped.
As for the engine. Porsche designed a new cylinder head.... Sump... Crank, pistons and rods. The only thing left was the cylinder block, and correct me if I am wrong, the bore of that was altered. Yes the 924 engine is the same as the LT van, just as the Lotus Twin Cam is the same as a Ford Cortina.

 

[vincematthews]

The myth that says that the 924 engine is the same as the VW LT van is just that.
The 924 was a design concept for a new VW sports car that was cancelled and bought back by Porsche. The original design was for a front wheel drive car and that idea was scrapped.
As for the engine. Porsche designed a new cylinder head.... Sump... Crank, pistons and rods. The only thing left was the cylinder block, and correct me if I am wrong, the bore of that was altered. Yes the 924 engine is the same as the LT van, just as the Lotus Twin Cam is the same as a Ford Cortina.

Yes, the bore was changed, I think from a diameter of 80mm on the 1.7L engine out to 84.4mm.
I can't imagine that the original designers would have ever imagined their 60 hp engine would one day be the basis for a 6th placed Le Mans racer with 375 hp., or more than 6 times the power output.

I thought the Mecedes connection might be handy as a counter to those who rubbish the 924 as being powered by a van engine.

 

[wibble]

Good find and bookmarked - always interested to know how these cars evolved. I read on another forum that someone has taken a step further than Porsche and achieved over 400bhp with new technology at hand.

Remember the other two Le Mans cars finished on 3 cylinders - a tough engine.

 

[vitesse]

Yes a brilliant piece of information-our 1st Porsche was a 924 Lux-which stood my wife well in place of the 2 previous MGB GT's & with the roof out ,was great in the summer months with the children in the back-sad to part ex it having just done an engine rebuild, for the 1st of our 924S's.
Was always interesting watching the mechanics at Lodge Sports "tuning " both their own 924's & other owners in the paddock at Oulton Park-no great high tech-just good old spannering with the engines really warmed up-slacken the distributor pinch bolt & twist about until max revs with quick throttle pick up,then watch them all screaming from the start line through Cascades like a swarm of angry wasps-indeed a great tough engine.

 

[pse_SC]

I can't imagine that the original designers would have ever imagined their 60 hp engine would one day be the basis for a 6th placed Le Mans racer with 375 hp., or more than 6 times the power output.

I thought the Mercedes connection might be handy as a counter to those who rubbish the 924 as being powered by a van engine.

Very good point, Vince - marvellous []

 

[vincematthews]

Was always interesting watching the mechanics at Lodge Sports "tuning " both their own 924's & other owners in the paddock at Oulton Park-no great high tech-just good old spannering with the engines really warmed up-slacken the distributor pinch bolt & twist about until max revs with quick throttle pick up,then watch them all screaming from the start line through Cascades like a swarm of angry wasps-indeed a great tough engine.

They did the same at Snetterton, and also setting the front suspension up with a plumb bob and school protractor . . . between races!
Those were the days . . . . . . . Oh dear, I'm sounding like an old codger . . . . ;-)

Has anyone tried the variable cam wheel, that the racers used, on a road car - or is the benefit marginal?

 

[vincematthews]

Sorry to revive this thread but:-

As the original source I quoted seems to be no longer available, I thought this would be a suitable replacement . . .

http://porschecarshistory...udi-driver-mag-012015/

 

[scm924s]

Discussing the origins of the 924 "van" engine is now boring[]

Much more interesting is debating the origin of the design!


The VW SP was produced from Volkswagen do brasil in São Paulo for the south american market from 1972 to 1976 .SP is an abbreviation for São Paulo or according to other sources Special Project or Sport-Prototype. Father of the project was Rudolf Leiding.
Rudolf Leiding was plant manager of the brasilian VW-plant from 1968 to 1971. The brasilian market was nearly independent from the headquarter in Wolfsburg. Under the code name Projekt X in 1969 the development department in brasil started to create a new sportscar on VW frame. The result was the VW SP1 and SP2. The first presentation of the cars was the german industrial fair in Hannover in march 1971.

From 1971 to 1975 Leiding was chairman of the headquarter in Wolfsburg. In that time period Porsche received a development request from Volkswagen to design a new inexpensive Sportscar to detach the Porsche 914. The project EA 425. The plan was to add the new car to the sales program from Audi. The Oil crisis from 1974/1974 avoid the plan while the VW management fear a weakening demand on the sportscar market. Porsche bought back the rights for design and construction in 1975, to sell the car under their own label.

 

[vitesse]

Stan,
A great post-knowledge is power[]

 

[russmw]

I love the fact that there is such a story behind the 924, far more interesting than "a company wanted a car so they designed then built one". Regarding the engine I suspect you could trace the history of any engine block and have red faced owners by the time you find its origin. Great cars.

 

[scm924s]

Compare the EA425 drawing to the 924 prototype.


https://www.evo.co.uk/por...-icon-1975-porsche-924

 

[vincematthews]

It would appear that the 2.0 litre engine was also used in the air transportable Porsche Type 2304/05 Wiesel (weasel) armoured weapons carrier of 1977 as in:-

"Porsche won a contract from the Army to design and build a light tracked vehicle, der Wiesel, which used a 2-litre Audi 100 unit mated to a five-speed Sportomatic transmission. Test drivers Mass and Ickx were said to be hard to prise from its driving seat." See below for photo:-

https://www.porscheroadan...of-porsche-excellence/

 

[lesworth]

It would appear that the 2.0 litre engine was also used in the air transportable Porsche Type 2304/05 Wiesel (weasel) armoured weapons carrier of 1977 as in:-

"Porsche won a contract from the Army to design and build a light tracked vehicle, der Wiesel, which used a 2-litre Audi 100 unit mated to a five-speed Sportomatic transmission. Test drivers Mass and Ickx were said to be hard to prise from its driving seat." See below for photo:-

https://www.porscheroadan...of-porsche-excellence/

Interesting article. I remember seeing Seat Ibiza's with 'Engineered by Porsche' stickers on the back window back in the day and chuckling to myself.

 

[924Srr27l]

Interesting article. I remember seeing Seat Ibiza's with 'Engineered by Porsche' stickers on the back window back in the day and chuckling to myself.

Yes I remember at that time it seemed weird than Porsche were involved with the Seat Ibiza's development but engines and gearboxes were developed in collaboration with Porsche hence the scripting on the engines and down the sill "System Porsche"

R