Why is it that whenever a RX-7 owner does an engine swap that they never run the motor inb the stock configuration? Everybody changes the engine to carbed or runs an aftermarket EMS? why don't any of you guys run the factory computer to start out with make sure everything works like stock then move to the EMS and other crap later? This is the only thing I don't understand about you rotory guys. i notice most of your cars have more problems then stock ones and never realize their true potential because of these issues.

I plan on the S5 NA 13B for my 1st gen due to the fact it is not turbo. i don't want all the extra crap in there and I'm sure the car will be plenty fast anyways considering the addition of like 60 hp and tq. i will be using all the factory parts to make it stock so I can referee the car and be legal in the great state of CA. Stock ECU.

P.S. the other thing I notice is that you guys seem to think wiring for an engine is hard to do. I understand that most people do not understand electronics but it's not hard to follow a wiring diagram. If you ever need help with a wiring issue my services can be paid for as I have built hundreds of factory looking custom wiring harness for many types of engines.

 

half of the 2nd gens problems stem from their crappy ecu's and harnesses. My t2 swap car on a haltech is daily driver reliable if you wanted to use it for that.

 

What's wrong with the ecus? I know most of the wiring hanresses are cooked and brittle. That's an easy problem to stop but what's the big deal with the ecus? They actually break? or they get blamed for problems that aren't actually a problem with the ecu? I know that happens alot. My buddy borrowed my T2 ecu to put in his T2 because he swore there was something wrong with the ecu but of course it was put in with no change to the way the engine ran. I just don't understand I guess and I'll find out the hard way. Or like most tuning groups of people whether it's hondas, toyotas, or whatever there just isn't many people that know what they are doing and that's the real problem.

I am not picking on anyone just want to know why as I don't see why the 13B would be any less reliable in stock form that my 12A is right now. I could be wrong though. And this message is not meant to say all rx-07 guys are idiots or anything like that. i just would like it explained to me why a guy would swap a 20B into a RX-7 then not use the factory computer to control it when all you would have to do is use the better part of the stock wiring combined with the car's stock wiring add some stuff mount all te stock crap in there and plug in the ecu when it's all done fire it up and have a reliable car. The 20B makes like what 300hp is that not enough for an RX-7 already? i can understand maybe for some people that want a drag car it isn't enough but for most street cars i don't think most people understand how much power that really is not to mention all the normal upgrades on top of it that don't require an ecu change.

p.s. i love the rx-7 forum and it seems you guys are definetely the most hardcore performance guys in the tuning industry I would like to see some examples of stock swaps in some of these cars. But I can't find any so I guess I'll just build one so I can see how hard it is. I am looking for low 14's to mid 13's with a NA 13B and some bolt ons.......................we'll see. The car's main purpose is autocross though which is why I am picking the NA motor instead of the turbo.

 

Why do people complain about what others do the their own cars?

Just a question... from a guy that's had three diffrent engines in his FB 12a, SBC, and SR20DET.

 

To answer your 1st question.
They want all the HP they can get. Alot of time they are not interested in reliability or longevity. Why? Because most of the new rotary people are young and the "IN" thing is to go as fast as you can. It's no big thing. This has been going on forever with car enthusiasts. In my day it was muscle cars and whatever we could do to make them go faster our paychecks went into it.

As far as wiring goes. It might seem simple to you but alot of people are not savvy when it comes to certain aspects of automotive repair or fabrication. I went back thru and read one of your threads about the removall of the air pump and install of an electric fan. The sympton you had stated that you were having was pretty basic and straight forward whether it was a piston motor or a Rotary.. Why was it basic for me? Because I have alot of experience with diagnosing.

As far as your swap with a stock motor and ECU, that's great. If that works for you then thats what you need to do. You could put a stock TII motor in there also and leave it stock and it will still go thru the referee as along as all the components are there. It all boils down to what you want out of the vehicle and what you are comfortable with.

I do agree with you about the reliability factor. It has always been and will always be that, "The more you modify the more problems you will have"! But that is technology and people are willing to do those things.

 

In regards to the 20B swap, they and the ecu are setup for automatics, not that compatable with the manual tranny swap any sensible owner would/should install, thus an aftermarket ecu/standalone is needed.

I do tend to agree that when doing a swap, installing the stock system 1st and making sure everything is performing as it should is a good 1st step for a working/reliable install. However, the stock ecu has serious limitations when it comes to achieving 275-300+ hp, thus, it's time for a standalone.

What upgrades are availible, while still using the stock ecu are limited and expensive, i.e., HKS. The R-Tek chips are a decent upgrade, but by the time someone wants over 300 hp, the stock ecu and intake system in particular, (maf) is a limiting factor.

Since most of us are not subject to CARB, it's prudent to go with a standalone for the increased tuning capability and replacement of the old, brittle wiring.

 

I plan on using the stock ECU in my T2 swap so not everyone on here go chaging everything around. But as everyone above said, its their car, so they can do what they want, you seem to be taking it personally or something, why? To each his own.

 

Guess Im the excption to your rule...

The stock 2nd gen EFI is not perfect,its got several common failure issues,including.....

Cold solder joint failures in the ECU
Nearly impossible to keep TPS adjustments
Triple redundant idle control system that is VERY picky
3000RPM cold startup revs, built into the idle control...not great for any engine
Very expensive OMP on the S5,which does fail on occasion
No check engine light or code memory on the S4
S5's, and especially S4/GSL-SE EFI systems are just plain ANCHIENT.They are slow and dumb compared to whats availible these days.....the best of the early 80's they are....not much of a thing to brag about.

Personally,I LIKE my S5 ECU and control system......it did take quite a while to get it all dialed in and running right.But now,and for the last 4 years,its been running P-E-R-F-E-C-T-L-Y.
All functions intact,CA smog legal and refferee approved,300HP estimated,still gets 20MPG on the highway,5 years and almost 50K miles of daily driving and roadtripping on the girl.
The N/A S5 engine is a great setup,very zingy and 160 stock HP.Ive always liked them.....but if you havent figured out all the hurdles yet,youll soon find out why so few people swap factory S5 engines into 1st gens....

 

I appreciate all your answers and it seems most of you run stand alones because you don't have smog issue where you live I understand that but a lot of people on here have to be in CA as well. I don't remember the smog pump thing exactly that the guy above was speaking of but i do know how I fixed what I can remember. By plugging the hose that went from the pump to the intake. I was told to leave it open which at the time made no sense to me but I was told so by a peson that has supposed knowledge of these engines. I plugged it and the motor ran fine. i no longer listen to him rest assured. i'm not talking it personally just trying to figure out why it's not done.

Why has nobody/company addressed the inherent problems with the ECU's? Is there no company for these ECUs like Hondata for Honda? I can't see such a big specialized market such as the RX-7 having nobody tuning stock ECUs somehow it's baffeling to me. I Guess no one cares to or something. I know a ECU which is pre OBD is pretty worthless and even the crappiest stand a lone would have better control over the engine but it seems a little odd that nothing has been done. Am I saying I'll do it no I'm not just looking for answers. I could do anything physically to the ECU but I can't do anything with the code. I will keep asking annoying questions I guess and getting answers till I'm satisfied. Sorry to bug you and I didn't mean any offense to anyone by any post just really curious why stock swaps seem to be hardly done on these cars.

 

if you swap a different engine into your car, it wouldnt be stock, so why keep the engine stock? :P

 

CARB, California Air Resource Board, allows for engine upgrades, as long as the newer engine meets the same emmision numbers as when it was introduced. this is the only way CA residents can leagally increase hp and still be legal to drive.

As far as ecu mods, RE Ameniya has done some work, there is an R-Tek chip, don't know if it's out for the S5s yet, and some other company that I can't think of off hand. The stock ecus suck when it comes to upgrading and that's why most go standalone. Anymore, the market is so small, not many are going to do any extensive work on them from scratch.

There is much more info on this in the 2nd gen section.

 

You can send your stock ECU into a company called Jet performance for recalibration.

 

Lack of market is a big part of it.
There are millions of 90's Hondas out there,and they are all pretty much the same when you get down to the nuts and bolts of them.They are affordable and reliable,with tons of aftermarket support.


1st gens are almsot all carbed,which makes them mostly obsolete in todays aftermarket world.........there are only a few GSL-SE cars out there..........the N/A 2nd gen makes up probably 80-90% of all the FC's,and the non turbos are ignored for the most part by power enthusiasts..........the 3rd gen is expensive and rare,although its the only RX-7 that has a real,fierce aftermarket following,probably due to its rarity and "still modern" performance abilities.

The turbo 2nd gens do have a fair bit of support,but they are getting older and older,and there just arent a lot of them around.And theres another reason......they are not the simple speed density type EFI you find on the FD,Hondas and others.Metered air EFI lends itself better to bolt on mods,but is more complex and is far more difficult to produce an aftermarket system for.No point in adjusting the ECU for more airflow and boost if the AFM cant flow it.Get too into the mods to adjust for this,and the smog police are gonna notice.Thats why Hondata,Haltech,PowerFC and all the others are based on a speed density type injection......its simple and super reliable once its tuned correctly.Thats also probably another reason the FD has so much support,it comes factory with speed density and is easier to adapt to a standalone system.

 

i just rebuilt the motor in my GSL-SE and used the mazdatrix 6-port streetport template on it. im using the stock fuel injection, racing beat short primary system, K&N filter and aluminum flywheel. it runs great and is peppy enough for me. ive had slow terds to fast *** cars and this one is my favorite just because i can get in, crank it up and drive.

but i also have a GSL with a 4-port streetported 13B, a dellorto 48 DHLA and full racing beat streetport exhaust and its fun as heck, too....just tempermental in the cold since i dont have the choke cable hooked up .

 

Lets see, aftermarket ECU's are easier and simpler to install, they have no limitation on horespower potential and tuning, you can do away with the airflow meter, they are relatively cheap... do you need any more reasons?