i was wondering what exactly made the s5 heavier. is it additional insulation, larger door bars, etc?

 

From my understanding the whole frame was beefed up. Resulting in better stability and safety. I read something about it recently. I can't remeber "EXACTLY" what was done, but that is what I got out of it.

 

Bigger gas tank
heavier parts for the extras like tools, jack and spare
extra metal to re-enforce dash because of the SRS/Mouse belts
Extra metal on the A piller, and B piller to support the mouse belt system.
extra metal in roof to support the mouse belts
heavier carpet (thicker nap)
Increased sound suppression
Options made standard (like power mirrors)
Front bumper support
intake and VDI
And cost cutting misc parts.

Nothing that really changed stability (except for the added weight) or safety (unless you consider mouse belts safer), just things that made the car cheaper to manufacture and still meet US safety requirements of the time.

The revised suspension, didn't really increase any weight, but helped isolate the body (which could be a good or bad thing depending on your point of veiw).

 

My 10AE weighs 2890LB, full of gas.
People keep trying to convince me that it's way heavier than an s5 vert or whatever, but really, people, think.

anyways, that's what my car weighs. Anyone have a stock s5 TII fully loaded? lets compare.

 

What do you mean isolate the body?

 

you guys think that the s5's increase in hp makes up for the difference?

 

The market in the late '80s tended to think the FB and S4 FC were a bit harsh when comparied to the Camero, 300ZX and Supra. I personally think they were more in touch with the road myself.

So, when they did the minor change Mazda refined the suspension with new springs, mounts and silly little things like the stabilizer bars end links were replaced with plastic ball joint ones instead of the firmer metal stud ones.

Those changes along with the increased noise insulation made the S5 more isolated from the road and overall feel, but a little more in-line with the luxo-sport barges that the 3000GT, 300ZX, and Supra had become.

Luckly, Mazda reversed that direction when they brought out the InfiniIV and the FD.

 

Maybe if they increased the torque as well it would have

but I think the extra HP only barely made up for the increased weight.

 

actually that is the same weight as my window sticker for my '88 'vert...

 

i was going to say, if they did it for frame rigidity then they f00ked up. my old 79 had a stouter frame. i was curious as to what all can be removed or switched out to lighten it up. obviously i would want to mess with the mickeymouse belts, but the bumper and spare **** should be easy.

 

Thats what I was leaning towards when deciphering what you wrote, but then I was thinking humm... he could mean soemthing else....

 

Yeah, a lot of the changes were because the revised CAFE standards in 88. The S4 cars would have been rated as gas guzzlers if they weighed the same as the S5 cars.

But when the standards got relaxed (and Mazda started getting FE credits because of the 323/Familia/Protege) Mazda could go back to using some of the heavier, cheaper to build parts that had been removed from the S4 to keep the wieght down.

But the SRS requirements are what really screwed the car with extra weight. I think someone weighed the S5 dash pad and support and it was like 25 lbs more than a S4 just there.

 

srs, you are referring to airbags right? because i don't have any and was wondering what models did.

 

2650lbs baby!!!

 

After reading many threads about the S4 vs S5, I thought I'd respond. Having purchased a '88 TII new (April '88), then a '89 TII new (May '89), I must say the '89 is a much more refined vehicle. The '88 with it's high exhaust temps, which created gas fumes from the tank to be expelled through the charcoal cannister into the atmosphere left a lot to be desired. The failing of the trailing ignition was something Mazda engineers as well as NGK personnel couldn't correct. The '89 is just a faster vehicle. You can feel it, esp. with the refined turbo.
Having said that, now for facts from the showroom catalog.
'88TII 0-60 6.7 sec 1/4 mile 15.2 (180 HP 183 LB/FT)
'89TII 0-60 6.1 sec 1/4 mile 14.8 (200 HP 196 LB/FT)
The '88 TII has a HP/weight ratio of 15.66-'89TII 14.94.
If the '89TII, with 200 HP had the same HP/WT ratio of the '88, it would need to weigh 3132# to be equal in performance, but it does weigh less therfore better performance.
Just my observations.

 

Sorry, in my haste to start cutting the grass...most important...Weight from catalog
'88TII 2850 '89TII 2987

 

S5 Turbo is very close to 3000 lbs.

HP increase in S5 cars dont make for weight increase (or makes just barely). It might look that S5 is faster than S4 when comparing stock to stock but in most cases it is because for example when you're conparing 86 N/A and 91 N/A, the 86 is five year older and in worse shape, but if you compare 88 N/A and 89 N/A, 88 should be faster not even mentioning that the torque is same. I personally think that the best N/A ever produced by mazda for US was 88 GTU, much more reliable and lighter S4 than any N/A S5. My second favorite is 87 Sport (that's basicly GTU in 1987) These are the lightest 5 lug - S4.

 

no, the s4's were always less reliable than the s5's.

You're right though, the age makes a big difference. I've been in two other fc's that were both 87's, and both were slower than ****. Neither one could get to 60 in under 15 sec. They were probably both closer to 20 seconds on the 0-60 run.

 

Less reliable? I made a thread about when engines died out. The S4's outlived most of the S5's. Must be because of the higher compression rotors on the S5.

 

SRS= Supplemental Restraint System.

On the US spec S5 coupes this was the mouse belts, on the S5 'verts this was the airbag (but note that the SRS reg didn't go into effect until the 90 model year, Mazda just jumped the gun on the 89 coupe).

As on the 90 production year (and later) all cars sold in the USA had/have to be equipped with a SRS system. A passive protection system for people that are too lame to put on their seatbelt.

 

Hmmm, on every one I have seen the trailing coil is the same for the S5 as the S4 so I am not sure what problem you had... They even use the same P/N N326-18-100A (also interchangeable with N327-10-100).

And I have never heard of the charcol vent problem unless the gas cap was defective. Perhaps a mis-diagnosis on the dealers behalf???

While the T2 did have a minor increase in the HP and more useable a increase of torque, I was for the most part comparing N/A FCs, where the extra Hp and torque only barely make up for the additional weight.

I will give that the S5 turbo is a better design and that Mazda did fix some major glitches in the S4 turbo cars, but things like the reduce road feel, electric OMP, and damm mouse belts suck away any desire for me to own one.

Intresting though that the Infini IV did go back to a stiffer more driver oriented suspension...

 

I think that response from owners on this board and recalls and TSBs would disagree with you.

 

Well, after cutting the grass, I thought I'd add:
I really don't believe there is that much of a weight difference between the S4 & S5. If you notice the conv is only 42lbs heavier, and the Turbo difference is that ABS and Power Steering was standard for '89 to account for much of the weight.
1988 Manual 2720#....1989 GTU 2800#
1988 Auto 2750 .....1989 GXL 2881
1988 Turbo 2850 .....1989 Turbo 2987
1988 Conv 3003 .....1989 Conv 3045

 

Sort of along the line of differences that no one has satisfactorally explained: S5 TIIs (and I think n/as) seem to stop better in the mag tests then S4s. Braking distances don't seem to vary enough in such tests to account for the differences.

 

Great information guys, clears up a lot of misconceptions. Also, nice points by Icemark.