Hi.
First of all, Merry Christmas to anyone who reads this post.

I have an 87 bridgeported rx7 that needs a little work. One of the first major things that needs to be taken care of is it needs a new exhaust because the previous owner kept the stock one, cut one side off and crimped it closed. I want to get a new exhaust, but I would like to know what exhausts any other rx7 owners would get that would keep my 5th and 6th ports working, but provide good flow to maximize the performance of the bridgeport. Also, I would like to have a single exhaust if anyone knows of one.

Also, I need some help tuning air and fuel flow. The car is running rich right now, and the car starts to hesitate a bit when passing about 5.5k rpms. When I bought the car, it came with a walbro, and I am nearly positive that I am using the stock ecu. If anyone could help me out by letting me know how to tune the afm and the fuel flow, it would help me out very much.

Thank you for your time.

 

uh... um.... uh.... i doubt it has a bridgeport. how do you know 100%?

 

a bridge wont run off the stock ECU will it?

 

I do know for sure that it is a bridgeport. Maybe I do have a new ecu. I do know its a bridgeport first of all because it idles at 1500 rpm, does the brap brap brap brap thing and the guy told me who rebuilt it and said it was a full bridge.

 

so just because it makes a brap brap noise its bridgeport huh.

just FYI none of that means ****, people can lie, idles can be set where ever you want, and rotary's tend to make that noise.

if someone was gonna spend money on a bridge port do you think they would be using a homeboy rigged exhaust????

if you think your new hot date whom you just met has *****. the only way you will know for sure is to dig in there and find out.

same can be said for you.....

 

just one guy's opinion. motors are a reflection of the owner. Take care of it and it will take care of you.

1. find out what ECU you are running.
2. get a wideband
3. talk to PO and get him to clarify specs on care and ask him any question you have.

get back with that info and I'm sure we an be of more assistance

 

Some more info is needed on the car. For example, turbo or NA?

If the car is turbo, then you are looking at a totally different upgrade path starting with a full turbo upgrade, FMIC, fuel system, exhaust, etc.

If the car is NA, then you need a good set of headers and a nice free exhaust system from the header back. Be prepared for noise.

In either case, the stock ECU won't cut it with a bridgeport. Will it run? Yes. Will it run well? Absolutely not.

 

The stock ECU has excellent driveability on a mostly stock car (that's working right) but once you bridge port the motor you need something highly adjustable to get the car to drive decently.

 

^^ +1 OP, take a picture of the set up.

 

Thank you guys for your help so far. It is an N/A model, I just thought I probably had a stock ecu because I didnt see an aftermarket one in the engine bay. I started poking around for it, and couldn't find it, and was then told that it was under the passenger carpet. I will take a look at it when I can, but right now I have a lot of work to do on it like replacing wheel studs, finding out whats up with the breaks(most likely only have to bleed them) and do a full tune up. The car runs well, it just doesnt like to cold start, and it runs rich low end and hesitates high end.

As far as exhaust goes, I have some aftermarket headers that are about as big as the stock pipe for each rotor. I was thinking that maybe i had enough flow going so that I could go with a turbo exhaust, like the hks silent hi-power, and maybe do something to keep all 6 ports open all the time since i get crap for gas mileage anyways. Does that exhaust sound like it would be overkill? I would like to turbo it(light boost, maybe 5-7 psi) eventually

 

I agree; you need to find out what you have first......

check the timing. Stock ecu with a bridgeport = fail.....it's going to run lean........

you're going to want a freeflowing exhaust....depends on how loud you can handle the exhaust noise.....cause it will be......

take your time and find out what you have.....

there are more than enough people here that can help you out.......

 

Mazda locates their ECUs under the passenger carpet, under an access panel, in the footwell near the firewall. This keeps them out of heat, moisture and other nasties in the engine bay. I don't know why other manufacturers don't know the same. Aftermarket ECUs are often not mounted in the stock location because people want easy access to them and are too lazy to simply run a cable down to the serial port and tuck it up in the dash. Most of the time they end up in the glove box or on the passenger kick panel.

If you have an AFM on the airbox, then you almost certainly do not have a standalone EMS.

Not starting cold, running rich and hesitating isn't "running well". That would be better described as "the car runs".

If the car really is bridgeported, then you will need a WIDE OPEN exhaust to get any sort of power out of it. Headers with 2" primaries that meet just after the firewall, then a 3" pipe all the way back with free flowing resonators and mufflers. It will be LOUD. Any quiet exhaust will restrict the engine and power will drop to near stock levels.

Turbocharging the car and then running 5-7 PSI is almost pointless. If your engine really is bridgeported, then you are talking about a full frame T4, a decent amount of boost and 500 RWHP.

 

I wouldn't believe it's a bridgeport unless I saw papers or the engine taken apart.

 

Ok, I got a chance to look at the ecu. Its a stock ecu, so I called the guy I bought it from, and he said that he got a piggyback chip and got the afm modified to adjust airflow. Confusing why he would do that.

Anyways, I was thinking about getting the greddy piggyback chip.

http://rx7.com/store/rx7/fcecu.html#greddy

 

i doubt a stock ECU would even drive with a full bridgeport, the fuel requirements are way different.

if he did manage to get it to run "ok" it still won't be adjustable with a chip. even piggypacks are crap for any real tuning. save your money and buy a real standalone. unless you have $ you're in over your head.

 

Any money you spend on piggybacks is a waste of money.

First off, you have the wrong intake manifold as well. Secondly, you need to do some research on what constitutes a good bridgeport.

I hate to tell you this, but you may be in over your head with something that's not what you originally thought it would be.

 

You can run a bridgeport on a S4 ecu just ask Bad83 on here he lives like 20 min from me and he and LongsturboFB built one and said wit the s4 ecu it ran desent but like Aaron said it wont run great. My 2 cents.

 

Hey guys, I really do appreciate the help again. Well, the car keeps having little stupid things happening to it, such as when it got cold here, the grommets on the brake fluid reservoir failed

Anyways, I have been poking around and doing some research lately, and have decided to get a standalone. I still have some questions though:

Since I will most likely be going with a haltech, what kind of intake manifold am I going to need?

The car was running and starting fine, besides the high end hesitation and running a little rich, until a heater hose, the one that goes directly under the alternator failed. I replaced that hose, but had to take off the alternator. What could I have done that would have caused it to start so poorly?

Thanks again

 

^ You shouldn't need to change the intake just the change the ECU. They are only related by the engine they are hooked up to. They do not directly affect each other.

 

I think you've made a dangerous assumption here...it doesn't get anywhere near cold enough in Orlando, Florida to affect the rubber parts of your brake system- if they failed it was due to age, wear or bad fluid (water contamination).

This should force you to question the integrity of the entire hydraulic system.

It's neither terribly difficult or expensive to rebuild the calipers and replace the MC (I've had better luck replacing rather than rebuilding master cylinders...YMMV), a procedure that will proactively address issues with a very critical subsystem.

A (not inconsiderable) side benefit of overhauling your brakes is that you'll have the car in the air and the wheels off, an excellent opportunity for you, as a new owner, to get up close and personal with all four corners of your car.

No telling what you might find.