924Board.org

[Lousailor]

All the verbage I've seen on the 924S says the 2.5L motor was detunned wrt the 944 with the same motor. What does this consist of and what would I need to do to get a 924S engine up to the 944 specs?

[exc911ence]

The engine was detuned by lowering the compression to 9.7:1 from the 944s 10.6:1 and, I believe, some slight reprogramming of the Motronic brain. The 88 924S received the high compression motor but your 87 (and mine, by the way) got the stunted motor. The easiest way to get the higher power is by swapping the chip in your Motronic with one from Weltmeister which promises a hike to 165hp. Of course, you could rip open the bottom end and replace all of the pistons with the higher compression ones, but that's darn pricey. I suppose that you could also have the head shaved to raise compression as well, but I don't know if the piston/valve clearance would take it.

I wouldn't worry too much about it since even the detuned 2.5 in the 924S can kick ass on a high compression engined 944. It's all about better power to weight and superior aerodynamics/less frontal area!

[gohim]

They called it a detuned version of the 944 engine when the 86-87 924S cars were made, but what really happned was Porsche increased the compression ratio in the 944 NA from 9.7 to 10.2 yielding another 10-11hp in conjunction with DME changes. In 88, the 924S was switched to the higher compression pistons, and the hp rating was the same as the 944. You can get most of the hp by swapping to the higher compression pistons, but the cheapest way to get them is by changing engines. You can use a 88 924S, or a late 86-87 944 engine.

[ This Message was edited by: gohim on 2002-04-05 17:16 ]

[exc911ence]

[gohim]

You could buy an 87-88 short block or a complete engine for $400-$600 from eBay, freshen it with new rod bearings and rings, then, resell your old engine when the new one is installed. That's loads cheaper and faster than buying a new set of pistons for $700-$900, taking down your car, and rebuilding your existing engine to incorporate the new pistons.

[Rick MacLaren]

Gohim is making wild assed guesses on those prices and doesn't know what he's talking about. I'd do some research to find out how many old 944 engines you can 'freshen' (Oh God) or 'rebuild' for cheap when the purchase price is $400!

Gohim doesn't have a clue what he's talking about.

[gohim]

rick... chick...chicken

Your acting very childish.

Going through this message board to post messages where ever I do to state that I don't know what I am talking about, when you admit that you don't work on your car, and state that snail transmissions have filters that need to be changed when rebuilding them.

Grow up!

[gohim]

A couple of people of contaced me to offer 88 10.2cr pistons in the $50-$150 each range.

A couple more people have contacted me to offer running 88 160hp engines for sale in the $550-$650 range.

At this point, it appears that as I stated before, the switch to a 88 160hp engine would be cheaper than reconditioning your existing 150hp engine after taking into consideration the cost of purchasing the 88 engine, reconditioning it with new rings, seals, belts, pulleys, and water pump, and reselling your old 150hp engine.

I have email someone about the cost of a chip to be able to use the additional compression (need new fuel map). And the cost of the chip must be added to the conversion, but costs still look good.