924S and 944
09-27-2002, 02:19 PM
#16
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"...I thought a trick the racers used to make the 924S faster was to swap out the gear box..."
I'm pretty sure that the stock 924S gearbox is one of the factors that make the car faster than the regular 944. The 944 (like the second generation RX7) suffers from having an "economy" 5th gear, rather than a slightly shorter, properly spaced one.
Car and Driver noted in its road test of the first 924S, that the 924S had a higher top speed than the regular 944. Even though the 944 theoretically could reach a higher speed at redline, it did not (at least in 86) because the car did not have enough power to redline in 5th. I think their 944 did about 130 max, while the 924S maxed at its redline... at about 136-137 mph.
-MAS
I'm pretty sure that the stock 924S gearbox is one of the factors that make the car faster than the regular 944. The 944 (like the second generation RX7) suffers from having an "economy" 5th gear, rather than a slightly shorter, properly spaced one.
Car and Driver noted in its road test of the first 924S, that the 924S had a higher top speed than the regular 944. Even though the 944 theoretically could reach a higher speed at redline, it did not (at least in 86) because the car did not have enough power to redline in 5th. I think their 944 did about 130 max, while the 924S maxed at its redline... at about 136-137 mph.
-MAS
09-30-2002, 09:06 AM
#17
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Ok. 
Fair enough. But the shorter 5th was on the S2, or so I thought.
There's more than one gearbox on that PDF. People do swap 'em. And the 924S, not being a turbo, has some limitations. So if speed is all you're after, well...I say go for it.
See the Porsche 924, 924S, 944 Transmission Calculator in the Porsche 924.org homepage. They show the 924S and 944 the same. I never knew that! Hmm. But in any event, the ones you could check out are the 944T, 944 TS (good luck finding one), 944S, 944S2. Each gearbox is going to have different characteristics, that's what I'm pointing out, and you can pick and choose which characteristics you like, depending on where you want the speed.
Personally, if I had a choice, (i.e., cash) and the ability to do the conversion, I'd toss a 6 speed into my 931. Just cause 6 speeds are so cool (like Ninjas lol)
Fair enough. But the shorter 5th was on the S2, or so I thought. There's more than one gearbox on that PDF. People do swap 'em. And the 924S, not being a turbo, has some limitations. So if speed is all you're after, well...I say go for it.
See the Porsche 924, 924S, 944 Transmission Calculator in the Porsche 924.org homepage. They show the 924S and 944 the same. I never knew that! Hmm. But in any event, the ones you could check out are the 944T, 944 TS (good luck finding one), 944S, 944S2. Each gearbox is going to have different characteristics, that's what I'm pointing out, and you can pick and choose which characteristics you like, depending on where you want the speed.
Personally, if I had a choice, (i.e., cash) and the ability to do the conversion, I'd toss a 6 speed into my 931. Just cause 6 speeds are so cool (like Ninjas lol)
10-01-2002, 06:58 AM
#18
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"...See the Porsche 924, 924S, 944 Transmission Calculator in the Porsche 924.org homepage. They show the 924S and 944 the same."
Then the info is incorrect about the 924S. I have several test reports (Car and Driver, Road and Track, Auto, and Michael Cotton's 924/944 book)that show the difference in the 5th gear ratios.
-MAS
Then the info is incorrect about the 924S. I have several test reports (Car and Driver, Road and Track, Auto, and Michael Cotton's 924/944 book)that show the difference in the 5th gear ratios.
-MAS
10-01-2002, 09:35 AM
#19
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That was kind of tertiary. The point of the discourse here is to help our friend, agreed? The point was: You can swap 'em out and get the configuration you want - suited to the power you're gonna put on the car.
If you supercharge it, or do a nasty rebuild, do you really want short 1st to 4th? Or do you want something longer?
If you look around, you can see the 924S and the 944 can both share the 016J transaxle. If you just click your browser and go to Pelican parts, you can SEE they're selling the same 924S/944 synchros. And you'll see they're not listing identical numbers for the 924S with the 944S and the 944 turbo. Why not? Cause they're different. But they list the ones for the 924S and 944 as the same. True, the 944 can also have the 016K transaxle. So all 944's don't have to be the same.
You can find evidence for this too on Danno's page. Go there and have a look.
I've got the PET CD. Have a look there too. That's Porsche's parts listing. I'm gonna do so when I get on that computer later today.
Admittedly there are ambiguities around the gearbox - people have to identify their gearbox based on the part numbers.
Does our friend have limited slip? That'll affect performance greatly. A swap could help a lot.
Does our friend intend on souping up his car enough to merit longer 1sts, 2nd and 3rd gears? If so, he can swap. Racers DO swap them out. And there are other gearboxes that can be used, again, depending on what configuration you want.
Your automotive magazine writers probably compared two cars and didn't specify which versions of the transaxle they were testing. Did they specify? If so, can you please articulate and clear up this matter?
If you supercharge it, or do a nasty rebuild, do you really want short 1st to 4th? Or do you want something longer?
If you look around, you can see the 924S and the 944 can both share the 016J transaxle. If you just click your browser and go to Pelican parts, you can SEE they're selling the same 924S/944 synchros. And you'll see they're not listing identical numbers for the 924S with the 944S and the 944 turbo. Why not? Cause they're different. But they list the ones for the 924S and 944 as the same. True, the 944 can also have the 016K transaxle. So all 944's don't have to be the same.
You can find evidence for this too on Danno's page. Go there and have a look.
I've got the PET CD. Have a look there too. That's Porsche's parts listing. I'm gonna do so when I get on that computer later today.
Admittedly there are ambiguities around the gearbox - people have to identify their gearbox based on the part numbers.
Does our friend have limited slip? That'll affect performance greatly. A swap could help a lot.
Does our friend intend on souping up his car enough to merit longer 1sts, 2nd and 3rd gears? If so, he can swap. Racers DO swap them out. And there are other gearboxes that can be used, again, depending on what configuration you want.
Your automotive magazine writers probably compared two cars and didn't specify which versions of the transaxle they were testing. Did they specify? If so, can you please articulate and clear up this matter?
10-01-2002, 10:40 AM
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I'm looking at the Porsche parts software PETCD and I'm seeing the same tranny in the 924S and 944, but a different one for the 9442. I'm also seeing Limited Slip provided for each, again with different numbers. I'll check the gears now.
10-01-2002, 02:33 PM
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So yes, swapping out the gearbox and getting away from a final drive you don't want would be good.
The 944.spec.com racing series puts the STOCK 924S and 944 gearbox final drive of 3.889 as the only allowable drive for their series. So you can check out the various trannies offered and other 944-based trannies will swap over. I'd bet even 6 speeds with work and money. So it depends on your budget.
There's a lot more you can do than just engine and transmission work. A limited slip differential would greatly improve your performance. And you'd feel it.
You can lighten your flywheel if you're so inclined.
Pop in a different engine management system.
Put on adjustable shocks.
Lighter, better wheels. Drop some weight elsewhere - get below 2600 lbs and you're really well ahead of other 944 drivers. You'll feel that too.
Or for top speed, lower your ride height.
The 944.spec.com racing series puts the STOCK 924S and 944 gearbox final drive of 3.889 as the only allowable drive for their series. So you can check out the various trannies offered and other 944-based trannies will swap over. I'd bet even 6 speeds with work and money. So it depends on your budget.
There's a lot more you can do than just engine and transmission work. A limited slip differential would greatly improve your performance. And you'd feel it.
You can lighten your flywheel if you're so inclined.
Pop in a different engine management system.
Put on adjustable shocks.
Lighter, better wheels. Drop some weight elsewhere - get below 2600 lbs and you're really well ahead of other 944 drivers. You'll feel that too.
Or for top speed, lower your ride height.
10-02-2002, 05:05 PM
#24
Race Director
Here is the deal on the 944/924S comparison.
I have both. In fact my 84 944 race is a little of both.
Chassis is 84 944 Engine & Tranny are 924S.
Engine (Apples to USA cars)
Same as in 87 944, M44/07 is the engine code and it is same engine code as late 944's. The early 944 uses M44/02. This is slightly different. No power gain can be expected. I use the DME from my 87 924S since it is designed for that motor. No need to change
1988 Motor is a different motor from the other years, but is used in both 944 and 924S in that year.
Transmission
87 924S has there same Ratios as 87 944.
The early 944s pre 85.5 have a .730 5th gear while the later cars have a .829 5th gear. The 924S all came with the .829 ratio 5th gear.
All other gears were the same
Peformance difference... None except for 5th gear.
Might make differnce on a track.
Remember that for top speed Air Drag is a big deal. A stock 924S will be faster than a 944 simply because of air drag. The drag coefficient is lower on the narrow 924S body than the wider 944. Also the narrower tires 195/65 15 vs 215/60 15 mean less drag. Even the slight different in tire diameter in the two sizes will make the 924S a bit faster...
However.... they really should be considered equal in most terms.
I have both. In fact my 84 944 race is a little of both.
Chassis is 84 944 Engine & Tranny are 924S.
Engine (Apples to USA cars)
Same as in 87 944, M44/07 is the engine code and it is same engine code as late 944's. The early 944 uses M44/02. This is slightly different. No power gain can be expected. I use the DME from my 87 924S since it is designed for that motor. No need to change
1988 Motor is a different motor from the other years, but is used in both 944 and 924S in that year.
Transmission
87 924S has there same Ratios as 87 944.
The early 944s pre 85.5 have a .730 5th gear while the later cars have a .829 5th gear. The 924S all came with the .829 ratio 5th gear.
All other gears were the same
Peformance difference... None except for 5th gear.
Might make differnce on a track.
Remember that for top speed Air Drag is a big deal. A stock 924S will be faster than a 944 simply because of air drag. The drag coefficient is lower on the narrow 924S body than the wider 944. Also the narrower tires 195/65 15 vs 215/60 15 mean less drag. Even the slight different in tire diameter in the two sizes will make the 924S a bit faster...
However.... they really should be considered equal in most terms.
10-10-2002, 07:42 PM
#25
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Ok so if you wanted a difference that was noticable, maybe, on a track, you might swap. And I hope I didn't give the impression I was ONLY referring to the 944 tranny.
It's also not unreasonable, if you're SOUPING up your car, to go with the 944 Turbo transmission. It's been done:
ram_one
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posted 08-16-2002 21:16
--------------------------------------------------I did it. '87 turbo tranny in my '86 na. Straight swap.
It is a dog from a standing start.
On the other hand, it is nice to hit 60mph+ in second gear. The gears are tall. I think I've used 5th gear twice since I made the change.
If you don't mind driving the car with the revs up, it is a great idea. I don't autocross, but I'd have to guess it won't help you in that scenario.
Personally, I don't mind it. I love keeping the revs up while driving.
--------------------
'86 944NA
Hunltey Stage II MAF,Milledge Cam,Bursch Headers
Soon to be 3.1L NA Sleeper (I Hope)
Again, it depends on WHAT KIND of driving you want to do and what your budget permits.
It's also not unreasonable, if you're SOUPING up your car, to go with the 944 Turbo transmission. It's been done:
ram_one
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User # 5718
posted 08-16-2002 21:16
--------------------------------------------------I did it. '87 turbo tranny in my '86 na. Straight swap.
It is a dog from a standing start.
On the other hand, it is nice to hit 60mph+ in second gear. The gears are tall. I think I've used 5th gear twice since I made the change.
If you don't mind driving the car with the revs up, it is a great idea. I don't autocross, but I'd have to guess it won't help you in that scenario.
Personally, I don't mind it. I love keeping the revs up while driving.
--------------------
'86 944NA
Hunltey Stage II MAF,Milledge Cam,Bursch Headers
Soon to be 3.1L NA Sleeper (I Hope)
Again, it depends on WHAT KIND of driving you want to do and what your budget permits.
10-11-2002, 09:25 AM
#26
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Sounds like I'd better go through and update that trans sheet... been taking some heat for that recently... have to look through the manuals to get the definitive info, then...
Put it on the ToDo list...
Put it on the ToDo list...
05-26-2003, 01:54 PM
#27
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</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by kcaK85:
<strong>I know that this is going to sound dumb to you, but I am not as well informed about these car as most of you. Here is the question. Can I take any regular, non-turbo, or S, 944 engine equipment, i.e. computer chip, or anything else, and put it onto my 1987 924S?
Thanks. kcaK85
</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">On a similar note, I'm curious as well about putting a 944 NA engine into my '81 924. Would there be lots of modifications, and what sort of modifications? Engine, transmission, suspension? Or would it be bolt-on? Pardon me for the lack of knowledge...it's my first Porsche and I'm still searching for information.
<strong>I know that this is going to sound dumb to you, but I am not as well informed about these car as most of you. Here is the question. Can I take any regular, non-turbo, or S, 944 engine equipment, i.e. computer chip, or anything else, and put it onto my 1987 924S?
Thanks. kcaK85
</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">On a similar note, I'm curious as well about putting a 944 NA engine into my '81 924. Would there be lots of modifications, and what sort of modifications? Engine, transmission, suspension? Or would it be bolt-on? Pardon me for the lack of knowledge...it's my first Porsche and I'm still searching for information.
1987, 1988, 924, 924s, 944, 94461812104, 944s, calculator, chip, compression, computer, gain, hp, porsche, raising, transmission
