which is better?

 

Red or blue, which is better?

There is no "better". Each series has it's own advantages and disadvantages.

 

I prefer S5 its front bumper looks better and the tailligts are awesome and it has a stronger engine

 

I've heard the S5 is generally considered a strogner frame and strogner engine.

Both are good though.

 

thanks for the info

 

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/ultimate-poll-s4-vs-s5-804353/

 

I have S4 and I have S5, both N/A, engines are better on the S5 but the body on S5 is a bit heavier, so the frame is stronger, I hate the electrical on the S4 always f... up, the S5 engine management system seems better than S4, I believe it is so because it is newer and was updated, also I find that S5 is a bit better on gas millage but I am not completely sure. The upper intake manifold on the S4 is different than S5, because of that, S5 has more top end power than S4, but S4 power band is much smoother. Interior on the S5 is nicer. And there is many things you can find on S5 that is better than on S4, S5 is basically updated S4.

So I say S5 is better than S4.

Alrighty ?!

 

I disagree!

 

The frame of the S5 is the same as an S4. Well, considering that both cars are unibody and neither actually have a frame, they're the same as they can be.

What it boils down to is preference. Some people like the updated look of the S5 exterior, some don't. Most people like the taillights. While the S5 makes more power, the car is also heavier so the numbers are about the same. If intending to build a high HP turbo car, then an S5 engine is a better start then S4. However S5 has an electronic metering oil pump which can cause some issues, and Mazda cheaped out on a few aspects of the suspension (integrated ball joints, plastic end links, etc.).

The S5 interior is virtually the same as the S4 save for some styling changes and the flexible stereo surround. The circle gauges appeal to some, but keep in mind the water temp gauge has three positions: cold, normal and "new engine".

So as I said, there are advantages and disadvantages to both and what is "better" depends on your opinion.

 

I guess each to their own! But I thought that S5 model unibody is reinforced underneath, to me it looked beefier, that is why being heavier made sense.

 

The S5 is heavier because it included more stuff and Mazda threw out some of the light bits of the S4 in favour of heavier pieces. But the bodies are the same. The 'Verts of both series have reinforcements.

 

i like s5's more but one of the downsides are the stupid automatic seatbelts

 

I forgot about the automatic "mouse belts". Here in Canada we got all our S5s with regular, normal, non-sucktacular seatbelts.

But yes, the mouse belts are a major problem. They are always broken and while they are covered by a lifetime warranty by Mazda, some dealers take major convincing to honour it.

 

Aaron is dead on the money. The integrated balljoints are f*cking retarded, especially since nobody makes aftermarket LCA's or replaceable balljoints. If you wanted to replace your worn balljoints you need a new LCA, which Mazdatrix sells, but for something like 350 dollars an arm! Also, the plastic front sway bar links are extremely cheap too and don't hold up for long.

Also, you forgot to mention the trannies and rear differentials are different. IIRC the S4 had stronger synchronizers than the S5 did. I can't remember for sure, but I spent a long time looking into the S4 V.S. S5 thing myself. The differentials are completely different in the fact that the S4 used a clutch-type LSD and the S5 used a viscous-type LSD. Also, didn't the S4 GXL have the AAS and the S5 GXL didn't?

 

there is more parts for the s5 motor i hear. the motor is lighter also. Body wise i like the looks of the s5. I had an S4 that i was swapping over. wish i finished the project.

 

Wrong - there would be more parts for the S4 if anything just because there are so much more of them around than S5s. The S4 and S5 motor should be the comparable in weight.

 

what are the advantages and disadvantages of the motors if i was just looking to use in a swap? are there any major differences that could be useful?

 

err

 

A disadvantage to the S5 is that it uses an electronically controlled OMP. If the car senses there is a malfunction with the OMP it will send the car into limp mode. The S4 is run mechanically off the throttle and does not use this feature. Also, the S5 OMP tends to fail more often than the S4's mechanical style. Of course the easiest way around this is to pre-mix, which I myself see as completely advantageous over the stock oiling system.

Another difference is the S5 N/A uses lighter weight and higher compression aluminum rotors. I would attest to say this is one of the reasons the S5 had a 8,000 RPM redline whereas the S4's is 7,000. Also, the S5 N/A uses a much better flowing intake setup compared to the S4 N/A. The S5's features a VDI (variable dynamic intake) which uses different length intake runners depending upon the engine RPM. IIRC, the S5 intake when used on a S4 motor usually ends up putting the S4 motor at roughly the same power as the S5, meaning a gain of around 15 HP.

As far as the turbo models go they are relatively the same besides the turbo IIRC. The S5 turbo is a twin-scroll design whereas the S4 is not.

Honestly, if you searching you'd see all of these differences as they have been covered numerous times.

 

aluminum rotors?? I wish!! That actually would be cool !!
The rotors are cast iron, only machined better, maybe balanced better too, it is a bit lighter then S4 my S5 rotor weight 10.5 lbs

I can rev my S4 engine in my S5 body up to 9000rpm no problem, only I don't know how many times I can do that before doing it last time!!

I tested the intake manifolds, I don't know if there is much difference, I think I had better results with S4 intake, the power bend was much smoother, but it started drop at high rpm unlike the S5 it would still go. But my 1/4 mile run was better with S4 manifold S4 engine and S5 management system all in S5 body.