924Board.org

dwak · Joined: 03 Nov 2002 Posts: 839 Location: Eastern Ontario

I keep reading that the 924S was detuned so as not to make the 944 look bad. Is this true or a myth?
If so how did they detune it and how do you undo it?

dwak the politically incorrect
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alexvex · Posted: Sun Aug 06, 2006 12:10 am Post subject:

If I'm not mistaken, the 924S has slightly lower compressoin than the 944. Thus, you'd have to get 944 pistons to gain back the power.
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--Alex--
1992 Porsche 968 (VW 2.5L I5 Turbo swap in the works)
1995 Audi 90 Quattro Sport (4.2L V8 Swap)
2010 Touareg TDI
Past Pcars: 80 931, 87 924S, 87 951

Chrenan · Joined: 15 Jan 2003 Posts: 3903 Location: Canada

I thought in 88 the "un-detuned" it so that it was the same as the 944 engine.
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1987 951 - M193 Version for Japan

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

The 87 924S engine was not "detuned". It simply was not upgraded.

For the 87 model year 944, Porsche made some changes to the 2.5L engine (primarily cr increase of .5 by changing the pistons). There was also a slight programming change for the DME.

This yielded an 11hp improvement.

The 87 924S did not get these improvements, it was given the engine version that Porsche used for the 86 model year in the 944.

For the 88 model year, the 924S was given the same engine revisions that the 944 got for the 87 model year, so the hp output jumped up 11hp.

Porsche never changed the transmission gears, and the 924S was always geared lower (numerically higher gearing) which was never revised. This is part of the reason that the 924S was always faster to the 1/4 mile (other reasons include weight and drag coefficient) than the 944, BUT was always rated with a lower top speed than the 944, although many magazine driving reviews show the indicated top speed of the 924S a couple of miles higher than the 944 (drag?).

dwak · Joined: 03 Nov 2002 Posts: 839 Location: Eastern Ontario

Thanks, Gohim. As clear and concise as ever.

dwak
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Llamaguy · Joined: 02 Jul 2003 Posts: 711 Location: Indiana

the top speed of a 924S was suppose to be higher than a 944 because the 944 didn't have enough power to hit redline in 5th, where a 924S with the lower gearing would hit (or some closer at least) to redline; which equalled a higher speed.
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1987 924S Guards Red
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Schreiberdeutsch · Joined: 24 Aug 2006 Posts: 42 Location: Macon Georgia

well true....but the 924S had a different 5th gear ratio then the 44 not so sure what it is but ive seen the road report b4.
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87 924S (Wrecked)
$5,000 worth of work done to engine

1995 Mustang GT 5.0