Newb here
 

Hello everyone, i have been checking out the site for about a month now, going through all of the helpful posts and have come to realize there are some creative people on here. Very nice forum as well. My name is Reese and i live in Arkansas. I have been drag racing hondas for a few years and primarily building my CRX. Today i finished my purchase of a 93 RX-7 with 39,000 original miles. Twin Turbo rotary that has not been modified and is an absolute beauty. I bought the car for 13,000 from a nice neighbor whom has had it for some time and finally gave into my demands. I got a loan from the bank for 16,000 so i could have some play money.

Mind you, I have plenty of Honda experience as i am a Honda tech here in AR, but have dealt with rotaries very little. I am absolutely excited to begin this project as well as join your community.

So here is the question, besides a turbo timer, intake and exhaust work, what sould I be spending my extra 3000 on? What are the most common problems with the FD(and what does that stand for) and also the best things for preventive upgrading.

Thanks again
Reese

EDIT: One more question, i have noticed that there are a lot of people swapping their motors before the 100k mark, are these not long lasting engines all the sudden???

Turbo Timer is a waste unless you really can't keep your foot off the last few minutes before you park. You should start with this thread ( https://www.rx7club.com/showthread.p...threadid=68640 ) which gives a good start to modifying your FD (Which stands for nothing, it is part of the chassis code). Definitly start with the reliability mods, not going for the highest power output.

All of a sudden? You've got alot to learn. This has been going on since day one. ;)

what i meant was do the rotaries not last as long under pressure? I have read a few posts where people generally are swapping new motors arounf 100k or even less.

depends how reckless people are with their cars, this is not a honda the motor doesn't get 300K miles, these motors need good tunning as the mods progress with out that you can kiss the motor byebye

Boost Gauge... and if you're getting over 10 psi a boost controller.

Already installed the boost gauge, would an AVCR do the job enough. What is the most common problem some of you are running into with the FD?

extreme heat .. also youll find out that lots of 7 had fire in the engine bay. so anything that can cool the temp down...

Hi CRX7

Well, this is easily explained...the coolant seals tend to brake if engine gets overheated. Not only that, but if you forget to change coolant regularly this will also blow your engine.

The thing with the seals is the following: Due to the rotary principle you have to seal the water circuit very well from the combustion chambers; if it breaks you have a wet engine, that means overhaul. Most common problem to make you notice a water damaged engine are severe starting problems.

You see, the rotary engine itself is very reliable. The difference is N/A or Turbo...only because of the boost you're able to crush it...the coolant probs mentioned above are a result of that.

I'd go with diablone and fd3s93...a good start are reliability mods, a boost gauge and, as mentioned, heat dissipation mods.

Reliability mods (as I do have on my R1 1993) include:

- Boost gauge
- All the important coolant and air hoses changed to sth more resisting heat (mine are Samco)
- Definitely a Downpipe

I consider a modified airbox not as essential, though. Opinions are wide spread as it comes to necessity. One says it just sucks hot air from engine compartement, the other says I really makes a difference...

These are basics only.

Good luck man (and trade in your HONDAs in order to get even more $ for FD mods :p: )

cheers
Patrick

Check your vacuum hoses too. That was one of the first things I had to change on mine. Along with that check plugs and wires.
Aftermarket Radiator is good too to address the cooling issue.

What kind of hoses should i get for the vacuum and other lines for replacement and where can i get them

Just ordered a greddy intercooler kit and will go with a new koyo radiator as my turbo rex has one and has performed flawlessly for over two years of hard drag raing.

"Good luck man (and trade in your HONDAs in order to get even more $ for FD mods )"
I was waiting for a honda joke, thanks for indulging me, but i dont plan on getting rid of either the drag crx or my 2000 accord with 90,000 miles and a value of 18,000 still.
Where are these coolant seals at?

It is understandable that a car under constant boost since day one would be more liable to get into trouble but i would think mazda would have beefed the engine up a little more.
As far as sealing the water curciut, does this mean some kind of rotary head gasket?
Thanks for all of your help as well.

just my two cents, but with 3gs for the just the engine/performance. sounds like you already got the boost gauge, intercooler, and radiator, which musta set you back about $1200-$1500. I would go with the following.

-change the oil and get new sparks ($50-60)
-downpipe ($150-$300)-reliability & performance
-turbo timer ($115 w/ harness) - personal opinion it is gonna give you some extra life on your turbos.
-highflo cat (or midpipe, but watch for boost creep) and catback ($800-1$$$) for both)
-intake($200-$500)-more air = equal more power-my preference is the blitz SUS($300), but I am not sure how well that works with the greddy intercooler.
-Greddy Profec B Spec 1 Boost controller($300) - not pretty, but simple to use.

This puts you somewhere around $2000. I think personally I would have put my money into and fuel management system/upgraded ECU before that intercooler. you can do reprogrammed ECUs for like $500-700 or do something like the Apex power FC and commander for about $1200. This will become crucial if you are gonna start turning up the boost. you gotta keep a rotary supplied with fuel, detonation is very bad.

This reply is so long i lost track of everything. if anyone else has something to add. knock yourself out. I am sure there are people that will disagree with what I say, but I have all of this put the Power FC on mine and I am happy with the results. The PFC is coming soon. with an FM intercooler to follow.

@CRX7

For the coolant/air hoses I prefer Samco's. Probably there is sth better around but that wouldn't be too affordable (for the value you get), see below.

For the vacuum hoses I'd go for hoses made of "Viton". "Viton" is a material that is extremely resistant to heat. On the other hand, this is expensive, too. But for the Turbo vacuum lines (if you decide to stay "Twin" -> original setup) it is definitely the material to get. There are like 200 of 'em and if one goes bang you'll lose boost by an instant...therefore: One time set up with these "Viton" things you would not have to worry the heat prob when it comes down to the TwinTurbo control mechanisms. And for the diameter needed, you can afford them (that's why I go for Samco within the large diameter things).

cheers
Patrick

Sounds like you intend to mod it quite a bit. I would throw down some of that $$ on a Power FC and save yourself any headaches in the future.

Thanks for the help guys. I dont plan to go all out on the car as i already have on the CRX, the RX7 is for reliablility.

@CRX7

See the attached file.

The seal is a "lip" which seals the surrounding chambers (for coolant) from the combustion chambers (that is where the rotor turns into it).
And yes, that's right, the seals are a type of "head gaskets". The material used differs (I think some kind of special rubber).

As far it concerns beefing up a boosted engine: This was the weak point Mazda engineers did not pay attention too well.

:rlaugh:

You have got that the WRONG way around. But thanks anyways I was in a bad mood and needed a good laugh this morning :D

If your seven is for reliability I think your in for a surprise ;) . If you want a "reliable" FD here's what you should do (I know you have some of these already):

1) boost gauge
2) Down Pipe
3) Koyo radiator
3) Aluminum AST
4) Eventualy replace the coolant and vacuum lines

I'm just warning you that your going to want to mod the hell out of it (i'm saying this b/c you like to mod other cars)... at that point keep the CRX for the reliability :) .

if his CRX is running 11s it is probably about as reliable as a rotary. i know hondas are tough, but not indestructible. you gotta be running some good stuff to be turning those numbers.

Did you have a white turbocharged CRX with a gutted interior? I went to MoKan a few times with some of my brother in-law's (Adam) friends. If so, I'm the guy with the black Turbo II that beat you :biggrin: and blew out his clutch.

Nice to see that you got an FD, I bought one a couple of years ago.

There are plenty of posts about reliability mods. Generally what you need is a downpipe, boost gauge, temp gauge, fan mod (search, it's easy), aluminum AST.

Only replace the radiator and vacuum lines if you need to. I put in a Koyo radiator because the factory one sprung a leak. I'm replacing the vacuum lines because I have some boost problems.

The engine itself is very reliable, it's all the crap that Mazda puts on it (like twin turbos) that kill reliability. The FDs have a bad reputation for being unreliable because of the restrictive twin turbo system and pre-cat that keep so much heat in the engine, and the engine compartment is so tight, and rotarys generate so much heat anyway that all of the other stuff (wiring, hoses, etc) start to deteriorate. Also, the factory ECU could've been designed to be a little more forgiving. Not to mention the fact that the dealers have no idea how to work on them.

The keys to reliability on an FD are to manage the heat, keep the boost down to 10-11 psi with no spikes, replace the plugs every year, do the reliability mods, in addition to general automotive maintenance.

:rlaugh: That was great.

I don't think anyone explained that FD refers to the VIN on 93+ RX7s. All these VINs start with 1JMFD... (as yours should :)). Second gen 7s are FC and first gens are FB for the same reason.

Nice pickup, by the way. Keeping the damn thing cool is key, so make sure you have a temp gauge. The intercooler will help, as would a bigger radiator. I run my fans all the time and sit at about 83 celsius without fail 'cause I'd rather spend a couple hundred on worn-out-fan-motor replacement than a few grand on a rebuild.

Enjoy

I don't think anyone explained that FD refers to the VIN on 93+ RX7s. All these VINs start with JM1FD... (as yours should :)). Second gen 7s are FC and first gens are FB for the same reason.

Nice pickup, by the way. Keeping the damn thing cool is key, so make sure you have a temp gauge. The intercooler will help, as would a bigger radiator. I run my fans all the time and sit at about 83 celsius without fail 'cause I'd rather spend a couple hundred on worn-out-fan-motor replacement than a few grand on a rebuild.

Enjoy

http://www.rx7turboturbo.com/robrobinette/

http://www.scuderiaciriani.com/rx7/index.html

I don't think anyone explained that FD refers to the VIN on 93+ RX7s. All these VINs start with JM1FD... (as yours should :)). Second gen 7s are FC and first gens are FB for the same reason.

Nice pickup, by the way. Keeping the damn thing cool is key, so make sure you have a temp gauge. The intercooler will help, as would a bigger radiator. I run my fans all the time and sit at about 83 celsius without fail 'cause I'd rather spend a couple hundred on worn-out-fan-motor replacement than a few grand on a rebuild.

Enjoy

Whoops, typo. that's JM1FD

...and for some reason that reposted like twice so i'm gonna just stop now.

oh also, since your going to be modding your intake and exhaust paths with a new intake, intercooler, downpipe and catback, you definately need some sort of new ecu, either a reprogrammed one (such as a pettit or M2 stage 3 ecu) or a reprogrammable one such as the Apexi Power FC with commander, UNLESS you plan to keep your boost at or under 10psi, which for some reason i get the idea that your going to go above that.

highest safe psi for stock ecu is 10. With your downpipe, exhaust, and intercooler in your boost will increase and you will likely experience some boost spike or creep so you need a controller as said before...Highest safe psi for reprogrammed or reprogrammable ecu is around 14, 14.7 if your gonna really push it. Anywhere higher than that and your going to need some fuel system work and likely getting new turbos.

i would definatley suggest
new radiator (Koyo or fluidyne are radiators of choice by most here)
New AST (pettit makes an aluminum one for $140) the stock one tends to leak and if you aren't watching your temp gauge all the time you will need a new motor or Rebuild
Downpipe will help cool the enginebay, but also add hp
hose job Only when you have boost issues and are prepared for a long couple days of learning and cussing
NEW FUEL FILTER! can't stress that one enough, you will definatly cuss your brains out when u attempt this
New plugs (change them from the bottom, its much much easier, u will see what i mean when ur under there
Temp guage or linearize the stock guage http://www.geocities.com/MotorCity/G...structions.pdf

Next, since you already bought the greddy intercooler I'm assuming you have the greddy Elbow
This will require you to do something about the AWS (automated warm up system) hose that is hooked up to your stock intake elbow. I plugged mine, you can also leave it hanging but it will leak oil, or you can eliminate the AWS with block off plates. I guess you can reroute it but I don't see the point...The AWS revs the car up to 3000rpm when you start a cold engine, blipping the throttle will lower it. This is only for emissions requirements and I believe causes excessive uneeded wear to your engine.

Next, I don't know much about the greddy intercooler, but it will likely require you to install a new air intake just because the stock one (which is really the same if you fit it with a new K&N filter) is too big for most aftermarket intercoolers.
good intakes are M2 intake box (will likely have to get it used, but it is the intake of choice of a lot of members), crooked willow or rx7fashion intake box, Pettit intake, there are others but i have no experience with them.

About the Boost controller, if you can find a Greddy Pofec B spec I that will do fine, but it is easier and usually cheaper to buy the Profec B spec II, which works using the same logic as the first.

Last, People have told you that coolant seals going is a large reason that our engines need rebuilding, which it is (which will run you anywhere from around 3000-6000+, unless you rebuild it on your own and install it on your own, which will still run you around 1000).
HOWEVER, another big killer is boost spiking and running lean (hence the need for a boost controller and new ECU) This will cause detonation and will blow your apex seals (seals on the rotors in the engine). Rotaries cannot handle detonation even close to as well as a piston engine can. Blowing apex seals is really bad because they can take out your turbos and mess up your rotor housings on their way out.

I think thats enough for now.....

www.hosetechniques.com has some real good silicon vac. hoses.

I would get a downpipe if I would you. Get a cold air intake, M2 makes one of the best out there.

I know everyone says you should do the hose job for reliability, But honesly IMO if the car is running fine i wouldent touch it. UNLESS your planning on having a professional do it. I did mine myself, broke 3 soleniods and the car ran worse then ever afterwards. It took me about 16 hours and I am NOT a novice mechanic. I went parellel after that cause I was sick of it.

If it aint broke, dont fix it!

CRX7,

My goals are similar to yours - reliability all the way. I just got my FD 3 months ago and am in the midst of completing the reliability mods.

I am of the opinion that I would rather have my FD for the next 25 years and have it be "quick" then have it be "fast" and have it for the next 5.

As per reliability - and to recap - heat heat heat. Avoid the heat. If you have to put an bock of ice on your engine to keep it cool, do it. You will spend a lot less money on ice than on a new engine.

Downpipe rids you of the often faulty pre-cat, an aluminum AST (Air Seperation Tank) replaces the plastic stocker that cracks and leaks coolant (so therefore more heat) are the only "musts".

The radiator and intercooler are nice too but then you have to start managing the boost system a lot more carefully than w/ the boost gauge. A water temp gauge is probably the only other gauge you need.

Silicon hoses will eventually be put on just by sheer wear & tear - the heat makes the vulcanized rubber hard and prone to cracks. Silicone does not suffer that same fate. When you replace the hoses make sure they do a tie wrap job so they dont come off as you mess w/ the engine.

Oh yeah - one more "must". A daily driver - keeps the miles low and the reliability waaaay up!

Lastly - change your oil right when you get it, again 500 miles later. If the car has been sitting for a while thats a must.

Forget Hose Techniques. They're overpriced, and their kit assumes you want to rice out your car by covering everything including your hood prop.

Go to http://www.bakerprecision.com for your hose. There's plenty of info on the forum about vacuum lines.

no i dont want to rice it out, also, thanks for the pile of info, there is enough here to keep me busy for a while, but i have come to realize that i am gonna need to expand the budget a little. How likely is it that those coolant seals will blow, is this a common problem?

-Kinda a couple dumb questions from your local honda idiot here, but how is the ignition system set up, coil or distributor or other.

-How much would it cost me in parts to replace the coolant seals and where are they.

Again, thanks you for all the very helpful and great information.

Coolant seals are inside the engine, and will require a rebuild to replace. $4000+ for a proper rebuild.

A standard rebuild should not cost nearly that much. You could probably buy all new rotors and housings for that much.

You could to a thorough rebuild for less than $2k.

I've never seen a reputable rebuilder charge less than $2k for a "standard" rebuild. New rotor housings are $1000 (for both). That price is not counting R&R of course.

Oh, you're having someone bend you over. I didn't realize that. :-)

Post pics of the CRX. :)

Hmmm... post pix of the Rx ;)

I just took a few of both, i will post them tonight