Bluesmoke

I'm sort of a bit confused, I've been reading about FCs for a few days now. The general impression I'm getting is that the S4s are built better, but the S5 has more bells and whistles - and of course - more power. My eventual goal will be to find a turbo model and get it to say 220-240hp.

If prices are equal, which would be a better buy? Thx.

snowball

if price was the same i would take s5, but i made my s4 look like a s5 for $400 with bumpers moulding and tail lights.

classicauto

iTrader: (3)

buy whichever one comes along thats in the best shape and in your price range. Pretty much anything that was better on either can be swapped.

As far as which one is "better" you'll never get an answer...especially here....

Bluesmoke

Curious, why does the S5 have 20+ hp on the turbo? Is the turbo bigger, etc? What and generally how much would I be looking at to get an S4 T to S5 T power? Say around 200 horses.

91verty

different combustion on the s5 and a tad more psi on the boost. However many including myself will argue that a s4 is built better than a s5. I mean you have a few cosmetic advancments like the suround and of course nicer bumpers and tails.

But i have driven many of the s4 and s5 t2's and for some reason i am more partial to the s4. Just seems like they ride better and just seems more solid. But again thats my own opinion. Oh and the gear ratio is a little different too for the s5 as well as tyhe ecu and little things like a better afm, etc.

JCurry

iTrader: (6)

I thought the s4 afm was less restrictive than the s5. Maybe im wrong, correct me if I am...

rx7b13

the s4 afm is bigger but its more square like and the s5 afm is smaller but its a cicle. i ve talked to people with s5's and they say they wihe they had the s4 afm

the s4 t2 compression is 8.7:1
thw s5 t2compression is 9.0:1
the s4 n/a compression is 9.4:1
the s5 n/a compression is 9.7:1

what i am doing is running an s5 engine n/a engine with a s4 t2 turbo with about 10-12lbs of boost

i got the s5 engine for 250 bucks and i got the turbo and turbo manifold for free in perfect condition

91verty

I run a 93 929 afm on mien and it works beteer than the stock. Especially with the safc-2 and the wideband.

calrx7

s4 suspension is better. its alot more stiffer than a s5. thats the only reason why i like the s4. other than that, get a s4 and make the exterior s5 den u set D

MazterDizazter

iTrader: (5)

Or get an S5 TII, upgrade the suspension, and gut it to make it as light as the S4's, Like I'm doing

sykminded

amen

There are slight differences between s4's and s5's that just kind of appeal differently, depending on taste. S4's were stiffer, but slower, s5's were faster but tended to have 'quirks' more.

Ironically, I ended up with an 88, and an 89, and I love them both. I inted to take my s4, with the tighter suspension, and build it up, leaving my s5 all stock.

s4 engines are cheaper to rebuild, but you'll get more power out of an s5......

neodriftout

I owned both an s4 and s5 and here is my opinion.

The s4 seemed more responsive and you could literally feel the road through the steering wheele. The s5 feels more robust like its alot more car then the s4 for some reason.

Basically the s4 felt like a bad *** go-kart of a super miata while the s5 feels more together and polished.

NOPR

the S5 has a better engine, hands down. higher compression, more power, stronger casting on the rear iron on the turbos, better turbo design, etc. I'm not sure any one would argue that the S4 engine is better. the S5 is better looking on the exterior in most peoples opinion, especially its tail lights. however, the S4 chassis is better in my opinion. it has great thinks like metal endlinks, removable/replaceable ball joints, manual seatbelts (thats a biggy), lighter dashboard, better LSD (have fun installing an aftermarket LSD into an S5 T2 pumpkin), etc.

that being said, your best bet (assuming you can work on RX-7's) is to get and S4 chassis with 5 lugs, 4 piston brakes, LSD, and all the good stuff. Then, put an S5 engine in it using a standalone.

if you arent looking to do all the work, or dont know how, i'd say just get whatever comes along and is in nice condition.

91verty

Nicely put nopr. Thats basically what i was refering to in my last post.

ProjectR13B

iTrader: (1)

s4 lsd is better cus its clutch type. at least between gxl models, i dont know alot about turbo rear ends.

MrFC3S

+1 for S4, they are lighter, more basic and sporty, if its little stuff like the bumpers and such, it can all be swaped, thats what im doing anyway. Got an S4 GXL, and going with a ported S5 engine and intake/exaust, and S5 Externals. S4 General can be had for cheaper, and are if not as good as an S5, better imo. I cant speak for the turbo.
but honestly, anything you can get your hands on is good

oh, btw, watch out for the S5 OMPs, Eletronic, Unreliable and Irreplaceable... expensive too

idsigloo

I'm pretty sure the s4 t2 compression is 8.5:1.

Bluesmoke

Thanks guys. I know I'll end up modding it for a little more power, hence I think the Turbo S4 or S5 is what I'm looking at. I already mentioned that I'm looking to get around 220-240hp eventually. I'm not too familiar with what "opens up" a rotary for power, but is the 20hp difference between the 2 turbo models that significant? Say if I were to get an Anniversary model or any other pre-89 turbo model, would the cost be far higher to get it to the 240hp level than say getting a 89+ T and taking it to 240.

The reason I am mentioning the 220-240 mark is because a few years ago, a school friend had a 90' turbo. I drove his car once and I thought it just the right balance of power without getting too scary- and he mentioned that for daily driving, staying below 250 is preferable for the car. His car put out 244 I think.

Again, thanks for helping this rotary noob out.

sintri

just wondering, but no one else's engine has a giant number marked on it right?

rx7b13

yea it is. its been a while since i readup on the s4 t2. im more interested in an s5 boosted 6port