Silverbullet

hey all, this is my first thread here, so here goes...

i got offered an 85 RX-7 for a really nice trade (non auto stuff) and i was wondering how this thing would preform? Some places i've read stock 85 engine juiced out 180 horses, other places ive read it only pumped out 135 horse power, which is true?

SoRRoW

Well 85 what?

You need to say what it is,12A,or 13B

85RX7GS

iTrader: (1)

Sounds like an SE - 135HP stock and 180HP modified.

xxxHondaGuyxxx

Yeah..

You need to find out if it's carbuerated (12a) 101hp

or

Fuel Injected (GSL-SE, 13b) 135hp stock.

Silverbullet

wow the older ones are much weaker than i anticipated lol

SoRRoW

What do you mean the older ones?

Silverbullet

older ones as in the first gen

Maguire

iTrader: (1)

the highest powered na rx7 was only 160. and that was the '91. So, the 25 horses isnt really that big of a gap. and of course the 12a's are less, because of the smaller motor. However, the power can be opened up pretty easily on either car.

Terrh

iTrader: (7)

these cars respond REALLY WELL to modifications. Much better than a piston car. Also, keep in mind that stock the weight is only 2300... that's pretty damn light. My '88 weighs 2850, my '98 cavalier weighs 2710..

Silverbullet

wow i expected like 200HP stock lol, i guess a 1st gen RX7 isn't much of a racing car

RotaryMotorDisorter

Nope not much of a racing car in stock form. Double the HP and you should be in great shape. Dont forget that even in stock form they handle like a dream.

SoRRoW

Well he did say 85 meaning first gen.

It dont take much for therse cars to get up and go,dont let the 12A fool ya

BRealistic

While my 12a may not have much PEAK horsepower, remember that once in the power band (over4k rpm)rotary engines have a very consistent power delivery- so even though I have only just over 100hp, my car can accelerate better than a piston engine with 100hp peak and the same weight, or similar to a car with 100hp and lighter (like a Paseo). This is why I wish power was shown as a relative term (like average power available from 2k to redline) instead of just peak hp. peak HP can be very deceiving.
What are the best easy mods for more power? Exhaust, intake??

ChairborneRanger

What kind of power should I expect from a 13b with a full Racing Beat exhaust system?

Also, is there any need to modify the intake (keeping it N/A)? Does the 7 pull in cooler outside air stock, or should I look at some kind of ducting?

Also Also , does anyone have a power (hp/torque) chart for a stock '85 GSL-SE?

PaulFitzwarryne

The gen 1 is a 25 year okd design and the power to weight ratio is typical of that period. Most road tests compared it with the Porsche 924, equivalent performance but cheaper. By 1985 it was outdated in stock form and even the gsl-se lost out in road tests to the Honda CRX.

There are three things going for the gen 1
-its relatively light;
-it has a classic 1970s wedge shape look,
- the rotary engine has real potential for modified power compared with the equivalent piston engine.

The 1985 12A as stock in the USA produced 101 hp. With modifications you can get substantial power, up to about 350hp in a street machine, 700+hp in a race version.

The 1985 13B had a stock 136hp, this can be progressively increased to over 500 hp in a street machine using a Gen 2 engine and modern technology.

The stock car is cheap to buy and run. But if you want speed then $6-8,000 in modifications will get you a fantastic performance better than the latest Ferrari or Porsche.

MIKE-P-28

iTrader: (1)

see sig

never dynoed, but estimate to be somewhere close to 300

Silverbullet

hmm damn you people, making me confused lol

I was offered an 85 RX-7 for only $500. It runs pretty decent, what do you guys think? From what i've been reading on this thread alone, do they benafit from upgrades more than piston cars? Such as say a K&N filter would add on more horsepower on an RX-7 than it would on a say 300ZX (which i might be buying for a little over 1k)? Man, this is putting me more and more in a delima .

claytonjh1223

buy the rx7

Silverbullet

sorry but i'd like to see a little more than just buy the x or the y car.

RotorMotorDriver

iTrader: (1)

This is all the motivation I need:
https://www.rx7club.com/forum/showth...hreadid=104314



~T.J.

SoRRoW

Ive seen that car in person and Think I got footage of it on the track.

Silverbullet

BTW, i was offered for $700, not $500 sorry.

SoRRoW

I personally wouldnt pay no more than $500. for a 12A first gen.

I have seen to many and passsed up alot of good deals,

I bought mine a 84GS with 86k on it all stock,FL car no rust,$175 in the auction. and 10 mins before that bought my first RX7 a red 79.For $50. and sold it for $200. 2 weeks later

PaulFitzwarryne

Silverbullet. Sorry you are confused but a little more info earlier wouldhave produced better advice.

I now take it you are looking for a cheap sports car rather than one you can spend afortune modifying.

First the RX and ZX were rivals in the market place so new there was little between them. TheZX was more powerful, the RX made up for it in lightness. So their performance was nearly identical.

Over the years neither has become a classic so second hand prices have remained similar. The main difference is that repair costs on the RX are generally much higher, while it is more difficult to find a mechanic who understands rotaries. However 20 year old cars are getting to the endof their life, if there is a major problem itsbetter to part them because the cost of the repaircan be more than the car is worth.

In reality its a personal matter, do you like the shape, color, engine noise rather than an objective decision. At $500 dollars less I would go for the RX as a better deak if they are in the same condition.

The point about increased performance potential between a rotary and pistom engine relates to the design characteristics. A rotary can take a far higher level of modification without the internals breaking up. For example cutting larger ports for a 50% increase in power is far easier mechanically than installing an upgraded camshaft on a piston engine to give the same increase. However simple 'bolt-on' mods like a K&N filter [+2-3hp] would have a similar impact. The exception would be the header, the RX's is very restrictive and a relacement would give you up to 25% increase in power compared with a 10% in the ZX.

A possible deciding factor is RX owners tend to be more helpful and give sound advice and even on a good day to come over and help.

Whatever you decide, enjoy.

Silverbullet

thank you very much, i'll see if i can get it down to 450-500. You guys been great