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RageLtMan · Joined: 05 Mar 2003 Posts: 184 Location: Boston, Ma

I read a little tidbit on carrera models, and the GTP Lemans 924 was mentionned as a prototype runner of a 944 engine. however it states that the engine is a twin overhead cam with 4 valves/cyl, and a turbo. The engine was rated at 410 bhp, which seems somewhat high considering that 944 turbos put out no more than 247 (correct me if i'm wrong).

I'm wondering how many of these were there, and whether a guy can find or duplicate one (How much does it cost to rebuild an engine into that kind of monster?)?

thx
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1987 924S 2.5L SOHC.

Capt EZ · Posted: Fri Mar 28, 2003 5:08 pm Post subject:

That would be awesome. How would you keep the rubber on the road?
That's close to a 3 fold increase of the HP to weight ratio....I want one.
But then again the 3.0L 968 had 300HP if I'm not mistaken.(?)
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live as if you'll die today. - James Dean

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1987 924S

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

you could probably duplicate one but you would also duplicate the negatives as well - the engines were only designed to run for 24 hours 10 minutes. Basically you take a 2.5litre engine, wind the turbo to 2 - 2.5 bar and then try and hold the engine together. Nissan were pulling similar horsepower out of their 2.5l turbo race engines in the early skylines with the same sort of boost.

Remember, that was just before the turbo Formula 1 cars came onstream - 1500cc qualifying engines putting out 1100hp for 1 lap (well the BMWs anyway) and 800hp for a 2 hour race.

Ahhhh now a 968 engine pushing a 924 would be useable.
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1979 924 (Gone to a better place)
1974 Lotus 7 S4 "Big Valve" Twin-cam (waiting)
1982 924 (As featured on Wikipedia)

Learn to love your multimeter and may the search be with you

Zuffen · Posted: Sat Mar 29, 2003 12:11 am Post subject:

I've read somewhere it was one car and three engines.

The history of the GTP and GTR cars varies from year to year and race to race.

I think they found out the twin cam wasn't needed on a turbo car and not reliable at that level. The four valve per cylinder actually was a negative to a boosted car?
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Bob Dodd - 924turbo@cox.net
931 1982, 944 1982 euro, 924S 1988SE, 93 968 tip 06 Silver Cayenne S, 06 Black Cayenne S

I have Way too many cars, parts for the 931,944 and 951

RageLtMan · Joined: 05 Mar 2003 Posts: 184 Location: Boston, Ma

peter, are you saying that there's a 1.5L that can take enough boost to put out 1100? what is this this NOS aspirated as opposed to naturally? yike....
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1987 924S 2.5L SOHC.

Peter_in_AU · Joined: 29 Jul 2001 Posts: 2743 Location: Sydney, Australia

They were actually slightly less than 1500cc. That was back in the mid-80s. The actual horsepower was never officially published as far as I know, just guessed at.

Do an internet search. Here's a start http://www.bmwcca.org/Roundel/1999/0999oth.htm where the BMW engine designer is quoted as rating the engine output at "At least 1,300" then saying "It's probably more. But I don't know how much more--because that's as high as our dyno goes."

The acknowleged winner in the hp stakes was the BMW engines used in the Brabham cars. I have seen references to the qualifying engines developing up to 1500hp. This was back when you could qualify with one engine and race with another.

The race engines were rated at between 800hp and 1100hp at around 12000rpm (I think).

The downside of course was reliablilty. BMW being the most powerful was the worst and they really struggled to get the engines to stay together for more than 1 hour which is a bit of a problem in a 2 hour race. It was great racing.

Apparently the drivers hated the engines - all power, no torque basically 1000hp or nothing.
_________________
1979 924 (Gone to a better place)
1974 Lotus 7 S4 "Big Valve" Twin-cam (waiting)
1982 924 (As featured on Wikipedia)

Learn to love your multimeter and may the search be with you

Sveina · Joined: 02 Nov 2002 Posts: 92 Location: Norway/Sweden

Anyone have some decent pics of a GTP LeMans to post in here?
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Sveina
Porsche 924 1976 RoW NA
Porsche 944 1982 RoW RSR
Porsche 951 1987 RoW 400 hp+
Porsche 951 1987 RoW 230 hp daily driver
Dodge Viper GTS 2001 soon supercharged
MB E320 CDI 4matic 2007
x 4 Porsches and lots of cars from different brands