Ive been searching the forums and i cant find exactly what im looking for. so, i bought my car off of some dude sometime in january. its a 93 fd with, big fmic, koyo rad, cold air intakes, etc. at the time, i really didnt know much about the rotary or the rx7.
i started going on this site and eventually read about the power fc. i realized that my car was spiking to 14 pounds so i started to drive it nice. i saved up for the power fc and i took the car to an rx7 specialist. i was also having idleing issues so i asked them to fix that aswell. so they installed the pfc and the idle is great. i just cant put in the clutch from high rpms or else the car will stall. i am told this is because of the lightweight flywheel and triple plated clutch or something. its really hard to drive.
anyway, they fixed the idle but they told me that i couldnt run the pfc without a bigger fuel pump or boost controller. the car would run at 13 psi and they said the fuel system couldnt handle it. so i asked about the fuel pump and they said that they dont recommend running that much boost because my car has 98,000 KILOMETERS (not miles) which is roughly 61,000 miles on it. they said that my stock seals wont be able to handle this and that they might blow if i run 13-14 pounds even with the upgraded fuel. so im asking, is my car to stock/old to run that much boost even with upgraded fuel? sorry for the long post, help is appreciated.

 

forgot to mention that there is full 3inch exhaust all the way back. and i know that i dont need that clutch and fly wheel, its what the guy had in it. i also forgot to mention that they unplugged some solenoid so that it would just run 7 psi until i figure this out.

 

Your car is going to be a "little" harder to drive on the street with a triple plate clutch and light flywheel, thats normal for that setup. Also 61k miles on a FD isnt high at all, thats on the lower end from what Ive ever seen...reguarding your fuel issues, your on stock twins im assuming? And your running a midpipe? your getting boost CREEP not spikes. Your stock wastegate cant handle what youve done to the car, theres no tuning that, you have to either restrict your exhaust(put a cat back on) or port your wastegate, which can only go so far. Or upgrade your turbos.

 

If that motor has 61k miles on it I do not think you should be running that much boost pending what the compression numbers are. That many miles and the compression could be only O.K. (going off the nonsense mods done to the car thus far I am guessing OK compressoin numbers at best) and running that much boost will only quicken the process of the motor needing replaced. The car is certainly not "too stock" to run that boost level. Quite the opposite. You do NOT have the supporting mods to run that boost without damaging the motor!!

Not being able to run the PFC due without a bigger fuel pump or boost controller does not really make any sense. It has a base map for minor mods (not a full exhaust nor that much boost). It should be just fine to hook it up and let it run the car if you are running 10psi.

As far as the car stalling when the clutch is depressed at high rpm, I run an exedy twin plate with lightweight flywheel and I certainly do not stall at high rpm when I shift, or just push in the clutch. So I think you have another problem.

HONESTLY, I would highly recommend that you NOT run over 10psi boost until you educate yourself a LOT more. The wastegate needs to be ported if it is not to run a full exhaust or your boost will always creep even with a boost controller. Search for boost creep.

 

sorry i have a catback exhaust, and since installing the pfc i dont get boost creep. i didnt drive the car hard at all when i had it. but that doesnt mean that the previous owner didnt. ill need to get a compression test i guess. but assuming that i have near 100 on both rotors, and no boost creep (which im sure i dont anymore), would i be able to run 14psi with a fuel pump upgrade? i should be able to run 14 pounds of boost shouldnt i? they unplugged a solenoid so that i only run 7psi until i figure out what to do. and just to let everyone know I havent done this to the car, im just trying to fix what was already done to it before i bought it.

 

yes im running stock twins, yes i have a midpipe, downpipe, and catback exhaust.

 

14psi is too much for both stock injectors and pump. I'd change both and include a FPR to be safe...

 

spend some time reading the FAQ thread stickied in this forum

 

+1 on the injectors, i was running 12-13psi and my inj duty used to be in the high 90s and some times it would hit 99%, once it hit 100% good thing i got bigger ones

 

k thanks guys for the help. looks like ill be getting a compression test and if everything is good, ill be getting a fuel upgrade. need the $$$$ first so it might be a while. thanks again

 

Not sure if this is the proper way, but you can fix it by doing either of these:
Adjust the screw behind the intake elbow - may need to re-do idle learning on pfc after
OR
Adjust the 3 fuel cut rmps under rev/idle settings in the PFC (higher settings).

Both ways have worked for me...Personally I would take it somewhere to get tuned properly as this should have been done as part of the tune.

Ceylon

 

can u tune the pfc to run 10psi even without a boost controller? im on the stock twins

 

The PFC makes a poor boost controller. I would get a boost controller, limit that to 10 psi. I believe you can turn down the boost on the controller though.

 

Not thru the tune you cant, but you can research and find the correct size boost "pills/restrictors" and install them in your wastegate precontrol and waste gate control lines and get it to run 10lbs.

Also, spend the money to ditch the crazy clutch you have. It is completely unneccesary for the stock twins power capabilities. Realistically it is too big for 99% of the setups on teh market.

 

isnt 3 inch exhaust is causing the problem. as mentioned before the wastegate needs to be ported for that. pills and boost controllers aint gona do a dam thing.


differences in the atmosphere can cause the boost to spike some days and not on others.

 

YES, the full 3 in exhaust is going to cause him boost issues unless the items above (wastegate porting or exhaust restiction) is done.

I think you need to do so much more research before you start dinking with the car anymore. Get the boost set to 10psi and leave it the hell alone. Otherwise I look forward to seeing your "holy crap my engine just blew for no reason" thread in a few months. The questions you are asking on what to do so I can run more boost are answered on here in a million different places.

Although this motor gets more of a bad wrap than it deserves, it is pretty damn good at handling a lot of boost as long as you add fuel and controll combustion chamber temps. If you do not compensate with fuel, a rotary engine IS NOT forgiving and will snap an apex seal faster than you can blink. The FD is one hell of a car, but it is definately not for those who do not know what/how/why they are modifying it.

 

i do know stuff and thanks for ur help. just how to control the boost is what confused me. believe me ive read tons of these threads. im on here for hours every night. dont claim that im going to blow my engine im not that stupid. i know its limits. thanks for the help anyways

 

These motors can blow easily if you get boost creep (<-----search this term and my username), everyone is just trying to help you avoid a very costly mistake

You have no way of knowing the limits of your engine because you haven't pushed it, the problem is one hint of detonation (ping) can crack an apex seal.

I'd recommend installing a stock main catalytic converter to keep the boost in check.....you can still make good power with it installed.

Also, as mentioned a triple plate clutch is for those looking to make something along the lines of 750+ rwhp (and the commensurate torque on a rotary), that is way way way overkill for your application. I would question the judgement of any shop that convinced you to have one installed......

 

The ONLY way to eliminate boost creep is to LIMIT the amount of exhaust gasses that the turbos get.

The wastegate controls this. If your wastegate can't divert enough exhaust gasses away from the turbos, they will just keep making more boost and spinning faster. This is determined by physics.

So your options are:
1. Port the wastegate
2. Put a restriction plate in the exhaust to slow the velocity of the exhaust gasses (or stock cat, something like that)
3. Spend the money on the proper supporting fuel mods to deal with higher boost

You really should do numbers 1 and 3 anyways.

 

Ummm.... Perhaps you should stop reading and start comprehending what you have read.

These people are trying to help you. You are obviously unfamiliar. We want to make you MORE familiar. We are HELPING you. Listen. Seriously.

 

yes im listening. thank u. its just that people are bashing me for stuff that im not doin. i didnt do this to the motor. i know it will blow with boost creep, hence i unplugged the solonoid so it runs 7.

what confused me was how to control the boost. i was being told by a shop that did some work on my car, that i need to buy a boost controller. i was just seeing if that was the only way, and apparently thats not truely what i need. i dont need to hear that. i know how to drive my car so that im not doing damage to it. thats why i installed the power fc etc. im trying to fix it. thanks

but seriously u guys thanks for the help. it is greatly appreciated. i know there is a search but i couldnt find exactly what i was looking for and i knew there would be people willing to help.

doesnt the catalytic converter just create lots of unwanted heat? im already running on the hot side with the front mount

thank u, this is what im looking for.

i have one last question. if i had the supporting mods (fuel, wastegate porting) how much boost could i run safetly on my seals? 61,000 miles, and idk if this helps but i vacuum at -14, 900rpm (that doesnt seem right) once again thanks.
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the clutch is triple puck, 2 plates. sorry i was in a rush when i began posting. its hks i think too. Anyone interested in a trade? lol

 

I you don't want to run any cats get your self a 2 and a half inch mide pipe with a resonator on it. you could even try cuting up mide pipe you have. think banana in the tailpipe

y

fwi- nobody on this fourm cares about your pride or feelings, don't get offened/neg, stay objective in your quest for knowledge and you will get alot of help on this fourm. what your are asking is some thing you should have know before you even bought your rx7. to sum of us it is a waste of topic space that has been covered a bizillion times . Check out fd3s.org. So if you take some of the bashing u can do anything you want to with your car with this fourm, info is out there, read. maybe mention the clutch in the forsale section.

 

Based on the above you don't understand boost creep. It will run at 7 psi until the exhaust gases and lack of backpressure overpower the stock wastegate. At a certain rpm the boost will skyrocket past 7 psi up to 10, 15, 20 psi depending on your setup.

With a stock internal wastegate the only way to limit your boost properly is by porting the wg or by re-installing a cat to give you backpressure.

also, 14 inches mercury at -900 rpm on a stock port motor is not good, it sounds tired. I'd recommend getting a compression check before doing any more performance mod'ing of your car.

a triple puck twin plate clutch is just about the worst choice for your application. This shop recommended it to you?

 

Mistake #1 - You don't buy a standalone ECU to fix a problem such as idle issues. You buy a standalone to be able to support running higher boost. You fix idle problems by adjusting the throttle body mechanical settings and TPS. There are links to this in the FAQ thread or you can find other threads in the Archives or by searching.

I don't understand how you couldn't find what you were looking for but the FAQ thread has many links that can help you understand.

No it doesn't.

If you just got the car, you should be worried about maintenance - not mods. Start with a compression test. Find a rotary shop to do that or they'll do it wrong. Read the fAQ to understand why. Do Oil, tranny oil, diff oil, brake fluid, plugs, wires, fuel filter, air filter, coolant hoses, maybe Thermostat.

15 year old cars require attention.