RX7 3rd generation

does anyone have any good mechanical knowledge of the rotary engine ? I need some help deciding if i want to buy one!

What can you mod on the rotary engine itself excluding turbos?

any good setups you can recommend ?

is nitrous worth using and stable on a RX7 ? cuz i know the engine is so
much different :confused:

sigh.

I know more about the rotary than you want to. but I dont feel like typing so head over to www.rx7club.com/forum

Yep, what he said. Also there is teamfc3s.org

According to Japan's infamous rotary meisters, RE-Amemiya; FEED; Knight Sports; PanSpeed, it is better to leave the engine internals original up to 350hp. Above 350hp, normally they use 3mm or lighten rotors to withstand the extra pressure. Lighter rotors increase compression ratio coz high compression means engine is healthy, strong.

Another alternative is porting. There are side porting(normal), bridge port, street port(mild) and peripheral port(racing). Porting is a must when you add big turbos and extra injectors to take advantage of the extra fuel intake for safer high revving and longevity.

I would recommend HKS To4s turbo kit and i/c upgrade or Trust TD06SH-20/25G turbo and i/c upgrade coz of availability option. Both upgrades can go up to roughly 450hp safely.

I am not familiar with nitrous so cannot comment at this point of time.

Unless you like to do a whole lot of wrenching on broken shit and engine rebuilding you don't want a 3rd gen RX-7 with a rotary.

The powerplant in these cars is a total POS.

I own 3 rotary machines so tell me about it...what is the broken shit and POS about then??? There is no lots of wrenching and engine rebuilding.

What do you know about RX-7 and rotaries itself??? Driving only a M3 you are not qualified to comment :o

My father owns a E30(ex) & E36 M3 and I have testdriven them for 6 years and it is still nowhere near rotary. I can tell you that rotary is as good as, if not better than BMWs.

Originally posted by Devilbat
Unless you like to do a whole lot of wrenching on broken shit and engine rebuilding you don't want a 3rd gen RX-7 with a rotary.

The powerplant in these cars is a total POS.

yeah, because you're the rotary expert! yeah total POS, 265 HP and 1.3 litres! yeah!:rolleyes:

the TT 13B has a higher specific output hp/liter than any other factory car on the road- 196 horsepower for every liter!!!

I think that devilbat is wrong about the "powerplant" in these cars being a POS. The only thing that might be wrong with these cars is the driver. The engine can be a great and powerful piece of machinery as long as you dont rag on it too hard. Thats where the problems begin, when the driver of the car over revs it or races the living crap out of it while its completely stock and expects after market performance out of stock engine parts, especially internal parts like apex seals, ports, and injectors. these things were made to only handle the amount of horsepower that the car came with stock. This car is awesome and can be one of the most dependable, most powerful street racing car you can find, if you know how to take care of it. For those who dont know how to or arent capable of understanding how this engine works, I pitty you when an FD3 pulls up next to youand makes you and your car look like a POS, plus, chicks dig 'em. :grey:

Yeah, it is true you have to upgrade the internals if you want to play rough.

As for NOS i have experience with it and it is very safe if you upgrade the fuel system exp. the injectors.

For specs order a catalog from racing beat (704) 779-8677. They explain it all very well...you have to have this catalog if you have a rx-7 or are interested in one..

And yes, if you cant pick up a chick in a fd3s something is very wrong. I had no problem in my 89 rx-7 gtu (black, 5spd & mint)..

piece

I dont think that MyGTR34 could have put it any better!!!! I totally agree with him!!!! If you want to play with the big boys in a stock RX-7, get 3mm apex seals!!!! They will handle the higher revs so much better!!

Originally posted by Devilbat
Unless you like to do a whole lot of wrenching on broken shit and engine rebuilding you don't want a 3rd gen RX-7 with a rotary.

The powerplant in these cars is a total POS.

Shutup. If you even OWN an M3 you can't say shit about a 12A,13B or a 20B, what else do you think the FCs came with besides a rotary? A four banger? :rolleyes:

much agreed...
if you don't want to replace broken stuff, upgrade the cooling system, b/c mazda skimped on it to save weight...

if you upgrade the cooling system, you should not have issues.

the factory manifold on most cars is cracked from the excess heat already, so you'll need to upgrade it.

switching to a single turbo will alleviate vacuum probs, which will be an issue b/c there's a rats nest of vacuum lines in there.

(i read somewhere that upgrading the vacuum lines, replacing them with better, nets 10-20 hp, depending on how shot your factory lines are)

there's not much to the motor to upgrade, as noted, b/c there's rotor housing, rotors, and not much else.

upgrade the cooling and vacuum lines, and you'll be surprised at the power you make

Originally posted by Steel


yeah, because you're the rotary expert! yeah total POS, 265 HP and 1.3 litres! yeah!:rolleyes:
2.6 on the 3rd generation rx7 if you want to use logic over stupidity.:help:
-Dave

Originally posted by Devilbat
Unless you like to do a whole lot of wrenching on broken shit and engine rebuilding you don't want a 3rd gen RX-7 with a rotary.

The powerplant in these cars is a total POS.
engine rebuilding is only needed if it's a race application and you got over 700 hp on it or if the rotary has over 100k on it or it's a oldie.

I see that no one bothered to discuss about using nitrous on a rx7 well i previously owned a rx7 and i use a 75 shot efi stage one which i also currently have on my scooby, and it keep's it stable enough, it's good for turbo rotary car's (does not apply for converted n/a rx7's) because it diminishes turbo lag how cool is that.
-Dave

2.6 on the 3rd generation rx7 if you want to use logic over stupidity.
-Dave

apples and oranges, einstein. The SAE says it's 1.3, i say 1.3.

Ive ALWAYS heard that the 13B was 1.3 liters, which is why it was called the 13 B, 13 being for 13 Deciliters. Ive even read on the Mazda history of rotary website that the engine was a 1.3 liter. So who am i supposed to believe? :bandit:

yeah that's what it say's eh.the 13B engine is constructed from two 650cc rotor assemblies. The engine operates on a 2 stroke cycle, hence, for comparison to a 4-stroke conventional engine, the capacity is doubled to 2.6L.

I used to have a 94 rx7 but quicly sold it 2 year's later for a civic then for my current car a 1998 subaru.

so a 250cc 2 stroke motor in a dirt bike is the same as "by logic" as a 500cc 4 stroke?

doubt that.

the motor is 1.3 liter. no other way about that one.

2 more strokes in the motor do not make it 2 times as big. where did the logic come from?

if you could explain it, maybe we could understand what you're saying.

hoo haha i already explained, I don't feel in the mood to say anything else.:flipa:
-Dave

The engine is 1.3L, in motorsport it gets timesed by 1.7 or something to get 2.3L or something so as to keep it in the correct class, that where evomaniac is coming from I think, but it is still 1.3L.

The engines will last well as long as U treat them right. Not warming the engine up before u cane t is the biggest killer with these engines.

Originally posted by FC3S
According to Japan's infamous rotary meisters, RE-Amemiya; FEED; Knight Sports; PanSpeed, it is better to leave the engine internals original up to 350hp. Above 350hp, normally they use 3mm or lighten rotors to withstand the extra pressure. Lighter rotors increase compression ratio coz high compression means engine is healthy, strong.

Another alternative is porting. There are side porting(normal), bridge port, street port(mild) and peripheral port(racing). Porting is a must when you add big turbos and extra injectors to take advantage of the extra fuel intake for safer high revving and longevity.

I would recommend HKS To4s turbo kit and i/c upgrade or Trust TD06SH-20/25G turbo and i/c upgrade coz of availability option. Both upgrades can go up to roughly 450hp safely.

I am not familiar with nitrous so cannot comment at this point of time.
U are getting compression and compression ratio confused. Compression ratio is say 9:1 on an FD which is how much the fuel is compressed before ignition.
Compression is how well the apex seals seal, say, anything over 100PSI means the engine is still healthy.

Porting is basically the same as changing cams in a normal engine, the bigger the port/ higher cam lobes, means more power but less driveability. And higher use of petrol since intake and exhaust are open at same time and unburnt fuel will escape out of the exhaust port.

Originally posted by phatdex

U are getting compression and compression ratio confused. Compression ratio is say 9:1 on an FD which is how much the fuel is compressed before ignition.
Compression is how well the apex seals seal, say, anything over 100PSI means the engine is still healthy.

Porting is basically the same as changing cams in a normal engine, the bigger the port/ higher cam lobes, means more power but less driveability. And higher use of petrol since intake and exhaust are open at same time and unburnt fuel will escape out of the exhaust port.

very impressive but you got the compression ratio wrong it's actually 9.0: 1 not to be picky just giving the "exact" fact's.

the rx7 comes with 3mm rotor's "stock".

Originally posted by Evomaniac
the rx7 comes with 3mm rotor's "stock".

you're full of shit.

not only are you full of shit...

but in math...

9:1 is the same as 9.0:1.

why are you being so anal about stuff you obviously don't understand?

the motor is a 1.3
for motorsports purposes or whatever, it's considered something different.

however,
straight from mazda, it's a 1.3.

it's registered as a 1.3

what don't you get?

why can't you explain the logic that you've not yet explained?

3 mm apex seals stock...

that's why most tuners UPGRADE to them on high performance motors?

right...

Originally posted by Evomaniac
the rx7 comes with 3mm rotor's "stock".

Mate, they come with 2mm stock. When I rebuilt my 13B my mechanic said it is better to stay with factory 2mm as they flex better and seal better. The only thing 3mm are good for is they are more resistant to detonation.
My car had 330RWHP and it was fine with 2mm seals.
My mechanic has 700RWHP on his car with 2mm seals as well, so u dont need 3mm seals.

Most of the time the engine is referred to a bigger capacity by ppl who are biased towards the piston engine. The capacity definately isnt doubled tho. I'm pretty sure its 2.3 or 2.4L they refer to it as. Its still 1.3L according to me.

Originally posted by flylwsi
not only are you full of shit...

but in math...

9:1 is the same as 9.0:1.

why are you being so anal about stuff you obviously don't understand?

the motor is a 1.3
for motorsports purposes or whatever, it's considered something different.

however,
straight from mazda, it's a 1.3.

it's registered as a 1.3

what don't you get?

why can't you explain the logic that you've not yet explained?

3 mm apex seals stock...

that's why most tuners UPGRADE to them on high performance motors?

right...
full of shit, my ass you dumb ass fukehead,anal what the fuke do you mention that for, got boofooed in jail did ya :finger:, I owned a 93 rx7 for 3 year's alright, now excuse me:mad: for giving everything exactly how it's supossed to be, logic i haven't explained :confused: lay off the crack pipe, and yeah 2.6 is how it's supposed to be also It does come with 3mm seal's stock as any rx7 enthusiast or any rotary enthusiast for that matter, you swear you can come in hear and talk shit to someone who previously owned a rx7 it might not be a skyline but it can compete with it, talking shit about me,eh.:D
-Dave
why the hell did I add that in, who cares anyway's.
my mistake 2mm stock, okay,okay.

For the last time, they are 2mm stock on a turbo engine. Go into a mazda dealer and ask for a set of 3mm seals and they will not have them because they dont make them!!!!!! 2mm standard I tell u.

The old 13B NA engines had 3mm seals, in the rx4 etc etc and maybe in the NA 12A too, so maybe thats what ur talking about, but the FC and the FD both had 2mm seals!!!!!!

I know it has 2mm seals because I totally rebuilt my engine, extend ported it, dowelled it and put a new FACTORY mazda 2mm seal kit in it.

Go to Ausrotary.com, one of the best Australian rotor sites and ask them what they think.

we're talking 3rd generation.:)
-Dave

They are still 2mm. I promise u. Mazda used to use 3mm in the older cars and then made 3piece (I think) 2 mm seals for all the turbo engines. Because they seal better than the 3mm seals. And thats what they would want on a stock factory car.
I just rang up my mechanic and he assured me they were 2mm.
FD yes?

Fd3s, I know for sure they are 3mm.
-Dave

Well I guess we are at a bit of a standstill, I guess we will agree to disagree.
But in ur other post u say u upgraded to 3mm racing seals.

No I purchased new ported 3mm seal's from pettit racing, they are rotary expert's and I knew they were the only one's who had product's for the rx7, a lot of product's, 2 1/2 year's ago.
-Dave

What the hell is a ported 3mm seal???!!!??!?

the engine :bloated: you from japan,huh? the thing's come ported to relive pressure.

How do they port the seals, I dont understand? Some explaining please coz I have never heard of them.

The seals are a 2mm or 3mm thin strip of metal, so how do they port them???

Am I from Japan??? No, I'm from Australia. I dont understand where that came from. =)

my ported seal's were ceramic unlike the stock, the ceramic material used has a lower coeficient of friction than the more conventional iron seals and the material is a lot harder. the lower friction means less wear to the surrounding parts (apex seal grooves, rotor housings, and side housings), and less wear to the seals due to both the lower friction, and harder material.this meaning that the ceramic seal's can take more detonation than stock, lasting longer and getting higher rpm's belive it or not, rotary genius.
-Dave

Stock apex seals can overheat, and warp which is not a concern with the ceramic seals. The ceramic seals although not indestructable, can take a lot more detonation than stock seals. They can also stand up to a lot more boost/power output.

U said ported seals, U said nothing about ceramic seals, and yes, ceramic seals have less friction and allow u to rev harder in NA cars, in turbo cars if they do break they wreck less stuff, yet I think u will find they cannot withstand detonation as well as metal seals, not the other way round.

I know what ceramic seals are, but I dont know how ported comes into it.

"CTHIS
The Bug Has Bitten


Joined: 17 Aug 2002
Posts: 489
Location: In the Sunshine State
Posted: Sun Apr 06, 2003 3:15 am Post subject:

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No they come with 2mm seals and I dont know what his talking about with these ported seals
_________________
S6 RX7 - 10.7@130mph
www.pacperformance.com.au "



This is a quote from a reply I got on ausrotary.com

in the u.k., japan,etc. we use 3mm stock, at least that is what i got,my car when i got did not seem tuned, but maybe it was detuned i don't recall iit perfectly.in the u.s. they use stock 2mm or ceramic 2mm seals.
now i got 3mm ceramic seals with dual springs and new rotor housings after and these were ported to resist the detonation, but the stock and modded get split anyway's, they die out.

I think ur engine must have been rebuilt before u got it, coz jap have 2mm standard as well.
And stop saying ported seals, coz the only thing that could mean is pieces have been cut out of ur seals.

I was lucky enough to get the seal's very very cheap instead of the $1100 a set pricetag.

And what are seals there for? To seal pressure within each chamber.

And once again, ceramic seals are more prone to detonation damage.

I had Ianetti ceramic apex seal's, before and these brand new were 1k more expensive the the one's I got, these were 3mm so my engine might have had a small tuneup.:rolleyes:

My entire seal kit including side seals etc etc cost $1800 AUS from Mazda.
Are u talking just about the APEX seals and nothing else?

Yeah, theres no way u have Ianetti seals on a stock engine.

The advantages of using apex seal's(3mm) ceramic are they can withstand higher rpms without floating, they can use a higher spring force than stock without adding any additional wear which gives better sealing.

And since u didnt answer my PM, did u look at the FD pics that I posted?

Originally posted by phatdex
Yeah, theres no way u have Ianetti seals on a stock engine.
exactly so I'm thinking my rx7 might of had a small tuneup but the previous owner just didn't wan't to spill the bean's because the Ianetti seal's had problem's with the rotor housings and that is why just after getting the car I had to change the seal's, that is maybe why she was so eager to sell me it, damn she got me good.

Yet 3mm seals cannot flex as much and thus at certain points in the rotors rotation they dont seal as well because the seals apex isnt the only thing that touches the rotor housing at certain points the sides of the APEX seal are touching and that where the 3mm seals are not as good.
The only thing ceramic is good for is not breaking stuff when they give way.
And 2mm VS 3mm, why do u think MAzdas early cars used 3mm and then they switched to 2mm for the later models???

So this means u r admitting that FD's have 2mm standard?
Also u have to use 3mm now because u cant revert to 2mm without getting new rotors.

yeah Iknow, mazda's racecar's use 2mm apex seal's(ceramic).

I'm not admitting anything, I really don't know if in the u.k. they are 3mm or not, i know i had them when i got them and they were from the U.S., weird.

They use ceramic because they have high stress engines that will frequently break when driving or they need to rebuild them frequently. Ceramic will ensure less damage to the housings and turbos if they let go.