Knifeboy

Hey everyone! I'm a newbie to the forum and I hope you guys can help me out.

I'm currently in the process of buying a 93 RX7 (touring I believe). I've performed a quick inspection on the car yesterday and it's scheduled for a full inspection and compresssion test at the dealership tomorrow. If everything checks out tomorrow, I'll have it washed and parked on my driveway before the end of the day!! Anyways, I've got some issues that I hope you can shed some light on (and you better get comfortable cuz it's gonna be a long post).

Here's what I found so far:
-Precat already replaced with downpipe
-Maincat is still in place
-Stock airbox replaced with a big-*** cone filter (I'll need to make a heat shield for it)
-Has turbotimer
-Has a muffler large enough to launch a grapefruit into the next city.

#1. I read somewhere that with those mods to the exhaust I would need to upgrade the computer or get a control module of some sort to make sure the motor is running on the rich side. Is this true? If so what should I be looking for?

#2. I revved the engine gradually and the rise in RPM felt proportional to the pressure I put on the gas pedal. (At the same time I listened for the spooling of the turbos at 2500 and 4500 RPM) However when I let of the throttle the RPM's would dip down to about 500 and kinda stutter a little. Immediately after it would settle at 800. Is this something to worry about?

#3. Engine sounds/appears to run fine. The only thing I noticed is that the pulley on the very left stops spinning at high RPMs while the belt keeps turning and all the other pulleys are spinning. Is this normal?

#4. I didn't see the stock AST nor was there an aftermarket aluminum unit. I'm assuming that the previous owner eliminated it altogether. (OR maybe I just don't know what hell I'm looking for) If the AST was eliminated should I still install an aluminum one? Afterall, it's there for a good reason right?

#5. The owner tells me that the person who looked at the car before me took it for an inspection at a local rotary specialist and supposedly they claimed that the motor was running fine. There were only some minor problems with some "bearings." She (the owner) couldn't tell me exactly which bearings needed attention cuz she didn't have a clue what all the tech talk meant. Is it safe to assume that Mazda will be able to locate these problem areas, or should I call up the other guy and ask him really nicely if he'd be willing to share his findings with me?

Other than that it's just some minor cosmetic issues which I'll deal with when I can afford it. Any insight/opinions would be greatly appreciated. Thanks in advance!


Jason

jmo87

iTrader: (2)

1. with intake, dp, and catback you wont need an ecu yet. not until you get a midpipe really.

2. dont worry about it.

3. do you know what pulley it is?

4. mixed opinions on ast's. mazda put it there for a reason is what i think.

5. it would be good to call the guy, and hopefully mazda would be able to tell you, but i dont know.

rynberg

my opinions

1. With a downpipe, cat-back, and intake, it is easy to blow your motor. The boost must be limited to 10 psi by some method (larger pills, boost controller, etc.) If there is no additional boost control and you have no boost leaks, the car may boost too much and you will run lean.

2. Your TPS may need to be adjusted slightly. Otherwise nothing to worry about.

3. not sure, the A/C does disengage at WOT. Are you sure the belt stopped moving? Any squealing or anything like that?

4. I would put an aluminum AST in there. If for no other reason, you gain more than a pint of coolant. Be careful when you undo the AST-elimination. Read up on it to make sure you undo everything (ex. pressure cap on filler neck).

5. You have an owner who doesn't seem knowledgable about her car. This could mean the car was not maintained or modded properly. I mean you have a seller who's backed out after getting the car checked out, what does that tell you? Also, most Mazda dealers are not competent at checking out or fixing FDs. About all you can trust them to do is to change filters and the oil. Well, atleast they can give you a compression check. Also, "cosmetic issues" can be VERY expensive to fix. Check out the classified forum for the price of used interior parts. Don't even look at Mazda's price for new. Also a good paint job is atleast $3-4k if not more.

65Imp

iTrader: (8)

#1 You are on the edge of the 3 mod rule here. If you see boost creep, look out. Next mod should be a ecu.
#3 if you are talking about the air pump pulley. (Upper left when facing engine bay) then it is my understanding that it should stop spinning at high rpm.
#4 I'd stay without the AST, mine runs without. Spend the $ on an upgraded radiator and intercooler.
Get the car checked out by a reputable rotary shop, forget the dealer... Good Luck.

Red Rotary Rocket

Knifeboy,

1. I believe that Wade has done some wideband testing and shown that if you limit the boost to 10 psi, the stock computer still provides enough fuel, provided your fuel system is working properly. However, with those mods, the turbos will likely make more than 10 psi. You'll have to use some kind of boost controller or swap out the pills to get boost back down to 10 psi.

2. You should hook up a temporary boost gauge to accurately test the turbo operation.

3. "The pulley on the very left" sounds like the air pump pulley. If it is the air pump, then the operation you describe is normal.

4. I have no opinion on this, but my AST is eliminated with no problems in the 1 year since I did it.

5. Ask who the "Rotary Specialist" is that looked over the car and call them directly. If this was recent, they should remember the car.

Hope this helps. Good luck with your 3rd gen...and when you finally get one, Welcome!

ziftar

iTrader: (1)

3. Air pump disengages automatically around 3500 rmps to avoid high rmp damage to it's internals. At least that's what I remember reading in the shop manual.

5. Hmm sounds fishy to me. Rotor bearings? Those would mean a rebuild. Maybe they where just referring to the muffler bearings. JK

Knifeboy

Hey Guys,

Thanks for all the feedback. Unfortunately I had to turn the car down cuz it failed the inspection and VIN check miserably. Turns out that it had a total of $13000 worth of damage from 2 collisions, the bearings in the front and rear wheels are worn resulting in excessive play in the wheels, turbos are leaking, power steering pump is leaking, engine is leaking and some other problems. The guys at the Mazda dealership thought it was a rebuild when they first saw it. I'll have to bite the bullet on the $$$ I spent on all the checks I did, but at least I didn't buy a wreck. Although I've been crazy for this car for the last 9 yrs of my life, I'm not crazy enough to buy a lemon when I could get one with no hits or major problems for a little more. As a matter of fact it turns out that there is a brighter side to this dark gloomy day of mine. One of the sales associates at the dealership is selling a white '94 Touring on behalf of a friend. No hits, mint condition, FULL service records, 105K kms, 100% stock. I'll be checking that out next weekend.
I may not be a member of the owners club (YET) but I'll still be a member of this forum. Again I'll like to thank you all for your help!


Jason

Knifeboy

GOOD NEWS GUYS!!! I didn't get to buy the White '93 Touring yesterday.......but I just bought the White '94 Touring today just a couple hours ago!!! We'll be signing an agreement later tonight and by tomorrow (or tuesday the latest) we should have exchanged $$$ and ownership. Now I've officially joined the club/forum.
I'll post some pics of car as soon as I get it.


Jason


Jason

Import Convert

Congrats dude! Treat her well!

Talek

I've got a white 94 touring myself, it's a beauty Congrats and welcome

Flybye

You are now....assimilated

ziftar

iTrader: (1)

Excellent! Get us some pics!!! Congrats on your FD purchase.

Knifeboy

Hey Everyone,

Finally got my pictures developed, scan, and posted online. Here she is.....

http://communities.msn.ca/KnifeboysP...nw?albumlist=2



Jason