rx7ian

becides the hp difference, what else is better on the later model? i've been looking for a 89-91 TII for awhile and i might just give up and get the older model. i heard the hp increase was mostly due to a better turbo, is this true? because i'll be upgrading the turbo anyways so will it matter? what else contributes to the hp increase? thanks in advance.

The Ace

89-91 TII: lower compression, but higher boost levels => higher HP (200 instead of 185)
Also a bit more extras, which result in heavier frame. Here in Greece all TIIs came fully loaded, so I dont know exactly the differences over there in the US....

DC350

87-88 TII 182 HP. 89-91 200 hp

rico05

He said besides just hp numbers.
Anyway, the exterior styling is much improved on the S5: more aggressive front lip, better taillights, better rims, etc. The interior is basically the same, except for steering wheel, gauges, and shift ****, as well as the S4 has manual seatbelts, while the S5 has the evil power assisted ones.

Now for power. Yes S5 has lower compression. The Kouki turbo is a little bigger, as is the wastegate. The intake manifolds are also different, for better air flow.

Icemark

Hey rico, the exterior styling is subjective, I think the S4 tail lights and front bumper (without the Mazda embossed into it like the S5) looked better.

rico05

Really? You're the first I have ever heard say that. Well, you're right..it is up to the owner. The S5 has round taillights, while the S4 has bar lights. The S5 has a more jutting lip than the S4. The black molding is my biggest qualm with the S4 however.

TurboII RudeBoy

the s5's hd highercomp engnes thn the s4's.the s4 was 8:5:1

j9fd3s

iTrader: (3)

the s5 also has a full range tps to run the electric metering pump.

mike

95R2-89TII Ground Zero

The S4 and S5 are different in the horsepower range, the compression, the interior, and a few exterior panels.

Akagi_Red_Sun

the series 5 had both higher compression and lighter rotors and higher boost from better turbo all adding to more horsepower.

The series 4 is lighter though, so they are close in the performance numbers.

rx7ian

ok sounds like most of the differences won't matter once i've modded it (turbo, wastegate, intake manifold, ect.), but what can i do about the lower compresion? it almost sounds like getting a earlier model is better if your gonna go all out, that is if your not concerned about loooks. thanks you guys are a lot of help i dunno what i'd do without this place.

redstreak

I like the S4 rear lights better, but I LOVE the S5 front bumper.

RylAssassin

wait wait if its about looks i always assumed you could buy s5 body parts and slap em onto s4? i mean im known for assuming too much but am i wrong, cant you do this??

rico05

I am pretty sure you can. But it may take a bit of cutting, drilling, etc. but should be relatively simple, i would assume.

RylAssassin

damn too much work for my lazy *** but hey the truth is the front of a s5 is soooo much nicer than a s4 and thats what im lookin to change on my 88 gxl. I mean itd be worth the work

redstreak

no cutting necessary, they bolt right on. The front bumper is a b*tch to get off though.

BlackFC

the S5 is HIGHER compression (9.0:1 vs 8.5:1) the rotors are lighter milled instead of cast...blah blah blah this has been discussed a million times over search.

pulse21

Hey I have a S5 Turbo II and I don't have MAZDA imbossed in my front bumper. Oh and I lover her to death, I had a S4, it's just not the same!

pulse21

love i mean, sorry

fuzzi

I dont like the steering on the S5's either... I think that the steering on the S4's is a little truer. The S5's have some sort of speed related adjust, and i find that when you crank it a little it sometimes does too much... this is just my friends S5 compared to my S4 .. but apparently there is supposed to be a difference.

benhart21

I am so with you on that one. Hell, if I got a S5, I'd put S4 tails on it.

My S4 has some sort of variable assist steering or something. Never checked it out or read anything about it, but it's alright.

relvinnian

No, they are the same on the turbo models.

Icemark

The power steering on both the series 4 and 5 are the same, with a vehicle speed sensing steering boost system. (This is different from the majority of NA series 5 versions and I am sure that is where the confusion is coming from).

The only nice big difference between the series 4 and series 5 T2 steering is that you can get series 4 T2 models with Manual steering with a 20.3 ratio, rather than the power steering that had a 15.2 ratio.

twinturbofan

Is there a difference between the turbo of the 86-88, and the 89-92?