Ice_Wolf

Well, I've decided to use my GXL as my daily driver and have been building up as one for a few months now. Now I'm wondering about upgrading it a bit and possibly swapping in some S5 parts. The first parts I'm thinking about are the drivetrain (axles, differential, transmission, driveshaft, etc.) I do know that the LSD's are different, the S4 being clutch type and the S5 being viscious type. What are the other differences in the drivetrains? I'm pretty sure the axles and driveshaft were the same, but I think the tranny had a different gearing and clutch setup. Thanks for the help guys.

Ice_Wolf

Well, I know for sure I decided to go with the right clutch setup and fluids for my drivetrain, but I'm still wondering about the differences in the drivetrains and if one was better than the other. Also, IIRC, many say using a SS line on the clutch cylinder is a bad idea because SS lines have a habbit of rupturing. Is this true? Also, is there any specific fluid that works best in the clutch hydraulic system?

RotaryResurrection

iTrader: (8)

First, difference between NA and turbo: http://www.rotaryresurrection.com/2n...in_differ.html

The NA stuff is the same across series (assuming manual trans), other than the flywheel, and the fact that some cars had LSD rear while some did not. Oh, and the tranny mounts will not cross over to the other series tranny because of slight mounting differences on the tranny case. There is also the GTU-S which had the 4.33 lsd diff and the different 5th gear tranny.

Speaking strictly of the turbo drivetrain...

Flywheels weigh and balance differently...the flywheel must match the year/series of engine it's going on.

Clutch can be either series. The PN's do sometimes vary but this was due to a revision in the disc thickness. Aftermarket discs vary in thickness anyway, so this is no concern.

Starters are the same.

Clutch slaves are the same.

Transmissions are similar and mount the same. The s5 5th gear is a slightly different ratio as I recall. The case has more ribs on it externally. The s5's tend to have more problems with 2 and 5 gear synchros than the s4, though they are a weakness on all turbo type R gearboxes including FD.

Driveshafts are the same.

Rear diffs mount the same and are the same size, but the internals are different. The s4 uses clutch packs for the LSD, while the s5 uses a viscous type LSD. It is to my understanding that most racers prefer the clutch style, though honestly I have never noticed a big difference between them.

Halfshafts are the same.

Ice_Wolf

Alright, so basically the only difference between S4 and S5 drivetrains is the LSD's then if the car came equipped with it. I figured the flywheel had to be different because the S5 can handle a higher redline, so I figured it was lighter or something. No big deal about the GTU-S parts, since they are more for race setups rather than a daily driver to conserve fuel.

Thanks for the heads-up on the TII stuff too Kevin. That answered a few of my questions I had from another thread.

Now, for a few more questions. What's different on the engines then? Here's what I know of:

S5 Stronger rotor bearings
S5 Higher compression rotors
S5 VDI intake setup
S5 Flapper type AFM
S5 CPU double speed

That's all I can think of for now. If there's any other things that I missed, please let me know.

Icemark

Only the manual tranny non turbos had a higher redline.

The S4 FC's used the flapper type AFM. The S5 used the cone or plunger type AFM
The CPU (body computer) was the same processor speed and was a simple 8 bit. Perhaps you are thinking of the ECU (the Engine computer)?

And don't forget the S5 higher compression rotors are also much weaker than the S4 design and pretty much require 2 piece apex seals instead of the original 3 piece design.

Ice_Wolf

Thanks for the info once again Mark. I never knew the S5 TII had the same redline. Was it the ECU that had double the speed then?

Ah, so ther is truth to the S4 drivetrain being stronger. With the synchros and rotors being stronger, those are pretty big things to consider. Also, IIRC, the high compression rotors actually have very little effect on the HP of the engine? And isn't the 3 piece apex seal design better than the 2 piece?

Icemark

Yes it went to a 8 bit processor as I recall.

IMO I don't really think there is hardly any difference between the S4 and S5 drive train. The tranny's are geared the same, and other than the syncro material (which really only matters if you use crappy gear oil or never change the gear oil) there really is not any difference. The LSD rear end on the S5 Turbo and GTUs model actually will never wear out... something that you can't say about the S4 clutch based LSD.

Well yes and no. Properly matched to the intake design, with the higher compression rotors are a good choice on non turbo applications. In other applications... not necessarily the same.

Again yes and no. The 3 piece seal better and the housings wear better, but in the softer material of the S5 and later rotors the apex seal seat can widen causing pre-mature roll out. You won't get that roll out with 2 piece apex seals.

But that is kind of a mute point anyway unless you have an old stock of 3 piece seals, Mazda stopped making them a few years back and I don't know of anyone that is aftermarket making 3 piece seals.

RotaryResurrection

iTrader: (8)

Huh?

All the rotors, including the lighter/thinner 89-95 ones, used 3pc seals. IN fact they continued using them up until the end of the rx-7 production in 02. Only in late 03 early 04 did the 2pc oem seal come out.

The only real issues with the lightweight rotors are the turbo ones can actually dent in slightly under high boost/power/detonation.

Now the thinnER rx-8 renesis rotors are quite weak and you can't really do any kind of milling at all to them without breaking through the castings, from what I am told.

Well, I have never checked PN's to see if s5 and s4 synchros are the same thing. But the s5 trannies (turbo) seem to have more synchro issues than s4. But they both have failures. I would say that both are equivalent in terms of strength, really. You can pretty much use whatever and it won't matter at all.

And the rotors being "stronger"...doesn't matter either. It's unlikely, if you're asking these questions to begin with, that you will be making enough power to damage the "weak" ( ) s5 lightweight rotors in any way, shape, or form.

Yeah, not so much. I could build 2 identical cars with different CR's and the average person wouldnt be able to tell me which was which after a test drive.

What is more noticeable is the rotor/rotating assembly WEIGHT/MASS. Stock series 4 rotors/flywheels are heavy. They have more intertia and therefore seem to be easier to pull out from a stop with, and have the feeling of more low end pull. But as rpms rise, this mass eats more and more energy that could be transmitted to the wheels so the top end doesnt feel as nice. It's the opposite for the lighter stuff...it has a more gutless low rpm pullout feel that the average person will notice (the engine is easy to stall when letting the clutch out for some) but the top end rocks. It's the exact same thing as removing a heavy stock flywheel in favor of a lightweight one. It makes it harder to drive from a stop or on a hill, but it makes the top end feel very nice.

So...mazda went from lower compression, but heavier rotors, to higher compression, but lighter ones. So...if you test drive an s4 car and an s5 car back to back. you will notice that the s4 has a better low rpm feel and is easier to drive around town, while the s5 has a better high rpm feel but is a little harder to take off on a hill with. You might think this is due to the compression ratio change, but it is really due to the weight/mass change more than anything.

RX8s have 10:1 compression rotors but the engines are just as gutless from a stop as the 89-91s with 9.7, until you get into the higher rpms.

No, the other way around. They claimed the 3pc sealed better, made more compression. I have made equivalent compression with 2mm 2pc, and 3mm 2pc seals. The 2pc design is way, way stronger as well. Which is stronger in a load-bearing application in construction...2 2x4s stacked on top of each other, or a single 4x4? Same thing here. Same total seal height, but 1 single long piece versus 2 split along their lengths is going to be more sturdy.

Icemark

I agree, I was just making a point that if I was rebuilding a S5 or later motor that I would automatically use two piece seals (even if I had three piece available), as the apex seal slot opens up at the top with use, much more than the S4 or earlier rotors.

coldfire

iTrader: (1)

according to Mazda documentation, the S5 tranny had synchromesh on the reverse gear. the S4 did not.

Ice_Wolf

So looking at this, the differences between the N/A's are the LSD, AFM, rotors, rotor bearings, intake setups, sychros, and ECU. What about the 5th and reverse gears, aren't they different? Also, is the flywheel different between them?

RotaryResurrection

iTrader: (8)

rotor bearings? OUt of everything that was written above, you got out of it ROTOR BEARINGS?

<sigh>

<----- unsubscribes from thread.

Icemark

can I do that too?

Ice_Wolf There are more changes than you can count.

How about this. As far as the drive line, there are only a few parts that are the same. The drive shafts and the starter and a few mounts. EVERYTHING else was changed.

Ice_Wolf

Yea, I don't know where I got rotor bearings from. I can't believe I asked of the flywheel was different because Kevin already said it was different. So I guess to recap things again:

S5 had viscous type LSD and S4 had clutch type
S5 used the flapper type AFM and S4 had the linear type
S5 had lightweight higher compression rotors (slightly weaker than S4)
S5 had a better flowing intake and exhaust manifolds
S5 had weaker synchronizers
S5 had a faster processing ECU
S5 had a different 5th gear and reverse gear
S5 had a lighter flywheel
S5 had a higher redline

Engine and drivetrain wise, that looks to be everything. The only parts that I'm interested in swapping to my S4 is the AFM and intake/exhaust setups. The rotors would be cool, but no reason to tear apart an engine that runs perfect right now. Was there anything else?

Ice_Wolf

Is there anywhere that I can find a writeup on all the parts you need to swap the intake and exhaust from the S5 onto the S4? Also, I thought I remember seeing something about swapping the AFM's too. Does anyone have the write-ups handy?

Ice_Wolf

Well, I found the AFM swap here:

http://img.photobucket.com/albums/v4...4me/s5ins4.jpg

Now all I need is the write up to swap the intake. I decided not to get the S5 exhaust manifold because it's the exact same as the S4 except that the S4 has a hole in it for the EGR gases to flow to the intermediate housing. They flow exactly the same, not to mention it's not worth trying to port the stock exhaust manifold since it's just a dump exhaust anyways. Anyone seen a write up for the S5 intake swap?

Ice_Wolf

Are there any companies that made aftermarket drivetrain parts for our cars? I've never seen aftermarket halfshafts, differentials, driveshafts, transmissions, diff mounts, or tranny mounts for our cars. I do know they make aftermarket flywheels and clutch kits though, but I've already gone through a thread about what is the best choice for a clutch setup for my car and changed all that stuff. I went with resurfaced stock flywheel and OEM Exedy clutch kit in order to save strain on the tranny and hydraulic clutch system. I know that lightweight flywheels don't absorb as much impact as the heavy stock one does, and don't want to risk my tranny going bad like my friend's Integra did with the ACT lightweight flywheel. Also, higher stage pressure plates are supposed to put more strain on the clutch system and cause things to malfunction faster, and copper puck clutches cause a much harsher engagement. Organic non-puck clutch discs are much more expensive, and out of my leauge for my type of car. Any idea on other aftermarket drivetrain parts?

Roen

iTrader: (2)

are the halfshafts actually the same? I've been told that for open to LSD conversions (such as the S4 clutch or the miata torsen), you need to use S4 axles/half-shafts?

Also, GTUs 5th gear vs. standard S5 5th gear is different as well. As is the 86 NA. Mazdatrix has a page that lists gear ratios.

fc pro am

iTrader: (8)

this thread is hilarious man..for real. Great questions though Ice Wolf, Ive been thinking the same thing myself as far as the differences between S4 and S5 drivetrain components. My 90 GTU is running the TII drivetrain and I havent had a chance to inspect it since I bought it to make sure everything is legit.

Ice_Wolf

Are there any companies that made aftermarket drivetrain parts for our cars? I've never seen aftermarket halfshafts, differentials, driveshafts, transmissions, diff mounts, or tranny mounts for our cars. I know that if I need something stronger, there's always the option of custom made things...

Roen

iTrader: (2)

uh.........you serious? Haha, as we tell other people...GO TO SOME RESEARCH! =P

Let's see....aftermarket half-shafts?

A bunch of places sell chromoly axles.....

differentials?

Let's see:
Mazdaspeed
KAAZ
ATS
if you have an N/A, the Miata Torsen or a rebuilt S4 clutch-type rebuilt to your lock-up specs
if you have a Turbo, the FD Torsen or a rebuilt S4 TII clutch-type rebuilt to your lock-up specs

Driveshafts:
ACPT I believe sells a carbon fiber driveshaft for our cars.....check RETed's site (www.fc3spro.com)

Transmissions?
HKS dog transmission
Guru dog transmission
3 types of NA transmissions (86, GTUs, and rest of the N/A's)
2 types of Turbo transmissions (S4 and S5)

Diff and Tranny Mounts?
Mazdaspeed has some (Front and rear)
Mazdatrix also sells Delrin and other solid mounts (OOH.....VIBRATION!)

Richter12x2

iTrader: (1)

Forgive me if this was answered already - no, you can go from an NA open diff to an NA LSD without changing halfshafts. Did it in my car.

If you want to put the TII LSD in an NA car, you need the T2 halfshafts and a custom driveshaft, OR the T2 halfshafts, a T2 driveshaft, T2 transmission, and T2 flywheel (for the correct series of engine)

Ice_Wolf

Exactly what companies sell the chromoly axles?

I think I'm going to rule differentials out of my budget also since the cheapest one I've found was like 700 dollars. I'd rather save the money for a rebuild in the next couple years since my S4 clutch type LSD is working perfectly right now. This is something I may look into more once I build a TII.

The carbon fiber driveshaft may be another one of those things that I wait for when I build a TII also. I know that our stock driveshaft is pretty light, but it's problem being that the U-joins aren't replacable. I would also consider switching to the carbon fiber driveshaft if I need to replace my U-joints. Any idea on what the pricing is for the ACPT one is?

For my application, I have the best N/A tranny to use since the car is mostly a daily driver. I've got the lowest geared 5th gear, which would help save in gas mileage. Do you have any extra info on the HKS or Guru transmissions and what prices would be? I'd be very interested in those once I do a TII build.

I just found the differential and tranny mounts on Mazdatrix's and Corksport's website. They are listed for a pretty decent price.

Thanks for all the info so far.

Roen

iTrader: (2)

You sure? I've read that if you have S5 axles, you need to use S4 axles instead. (I'm speaking N/A to N/A). Did you start with an S4?

$1000 for the ACPT carbon fibre driveshaft

You may be lucky enough to find a miata torsen LSD for the N/A for $350-$450 off ebay or searching through the forums for a dealer of torsen LSD's.

If you want to save money, a piggyback isn't a bad investment with gas prices the way they are.

Richter12x2

iTrader: (1)

I did start with an S4 - you might be right, maybe they changed the spline count between the s4 and s5?