Kento

It didn't really sell well at all. You do know the FD was only imported into the U.S. for three years, right? I'd call that a pretty short life. It was discontinued in other markets shortly thereafter, with only the Japanese domestic market getting the FD until '99.

There were a number of factors contributing to its demise. But the aftermarket has plenty of other cars that are still in production whose owners spend plenty of $$ modifying them.

FDNewbie

iTrader: (10)

Yea yea I know all that Kento. I thought by "selling well" you were referring to aftermarket sales, not buying and selling the car itself. Because, after all, sales of the FD from Mazda don't exactly correlate w/ it's aftermarket potential. In fact, I'm sure the aftermarket industry made more money off the FD than Mazda ever did.

I guess I don't know cuz I don't own any of those cars, and I only know FD owners lol. So you think the FD aftermarket industry is a small one, compared to other cars' aftermarket industries? (And I'm not comparing this to say, a Honda Civic's aftermarket industry lol. Something comparable)

BATMAN

After I had the warm-up butterflies removed and the "bridge" between the 2 ports removed the car seems to pull harder past the 6k~ mark with nothing else done.

Kento

Uh, aftermarket potential? How many FDs do you think are actually still on the road, compared to the myriad number of other popular cars?

You might want to ask some of those aftermarket manufacturers who make parts for other cars as well as the FD which sold more.

Well, imagine that.

See my second response...

FDNewbie

iTrader: (10)

Well I just found it interesting that no matter what aftermarket manufacturer's website you go to, they practically ALWAYS list FD-specific products. To me, that was a sign that they recognize there's def. money to be made off of FDs, and that it's a strong market - strong enough for them to design products specific for the FD, vs. "universal" parts...

the_glass_man

iTrader: (2)

FYI: FD production ended in August of 2002.

jimlab

The only manufacturers who have parts for the FD are ones for whom the cost of development was low enough to make it worthwhile, and many of them aren't even FD-specific.

For example, it doesn't cost a lot to make "FD-specific" clutches because the '86-'91 Turbo II uses the same size flywheel (240mm) and has the same input shaft size and spline pattern (1 x 23). Then again, so does the '88-'89 929, the '88-'92 626 Turbo.

Brake pads are a consumable product anyway, and there are enough people tracking and autocrossing their FDs that it wasn't difficult for aftermarket manufacturers to make a variety of racing pads for the FD... especially since the same pads fit the '86-'91 FC too.

Hawk front pads, 1995 RX-7 - HB155F580
Hawk rear pads, 1995 RX-7 - HB158F515
EBC green front pads, 1995 RX-7 - DP2763
EBC green rear pads, 1995 RX-7 - DP2729

Hawk front pads, 1986 RX-7 - HB155F580
Hawk rear pads, 1986 RX-7 - HB158F515
EBC green front pads, 1986 RX-7 - DP2763
EBC green rear pads, 1986 RX-7 - DP2729

On the other hand, there are no FD-specific urethane bushings because the molds required to cast them cost more than the potential number of sales would net. There are for the FC, because there are tens of thousands of potential sales.

The FD aftermarket is tiny, even compared to the FC's aftermarket, and you can thank the FC for some of that. However, the aftermarket for the FC isn't **** compared to some of the most common and popular cars, like Mustangs, Camaros, or even Corvettes.

SPOautos

Exactly, its a fixed length that you cant do anything about....except replace it with an aftermarket manifold that uses a different length runner thats geared more towards top end versus bottom end. The only reason I brought it up is because you made it seem like a flow bench is the end all be all information to design a intake manifold around. A flow bench doesnt take into account pressure wave tuning based on runner length nor does it tell you the optimal runner length for a specific engine, or what rpm band its going to be most efficient at.

You made it sound like no one knows anything about the lim/uim because they havent flow tested it. What I'm saying is that the max flow test on a flow bench wouldnt bring to light the runner length and pressure wave tuning issues.

Your right that this doesnt tell the original poster much about extrude honing, it was realy in regaurds to other posts in the thread that all seemed to follow my post saying I'd rather put that money towards a aftermarket manifold if he was worried about it.

jimlab

No, if you read my posts and understood what you read, you'd know that I was talking about using a flow bench to find the flow limits of the stock intake manifold. It hasn't even been proven that it's a restriction to air flow at volumes that even single turbos can produce. Seems like a logical first step to me...

We're not talking about designing a new intake manifold here, and you know it. Read the title of the thread next time.

The intake manifold was designed to work with the 13B-REW by Mazda over the rpm range the engine operates in. Wave tuning has JACK **** to do with this discussion.

FDNewbie

iTrader: (10)

Apparently someone believes it is a restriction enough to use a diff manifold. Ernie, can you or Dee elaborate on how you came to the conclusion that the manifold was restrictive at over 550rwhp?

Erdin

Found this. I think it may be of interest


Rotary Response and Racing.

Flow Bench - Tech findings.

--------------------------------------------------------------------------------

Air flow rates for FD3S intake manifold being generated....
Comparison tests between a stock and modified intake manifolds show promise....
Initial tests are showing a 4% increase in air flow through a modified intake and dynamic chamber...

--------------------------------------------------------------------------------

02/01/01-03/12/01
All parts tested are 1993 FD3S US Fed spec

Preliminary test runs of a modified intake manifold and dynamic chamber indicate that there could be a significant gain in air flow made for a reasonable cost.

Runs made on a flow bench using of a FD3S intake system mounted to FD3S intermediate and rear housings.

At 20in of H2O vacuum the flow was 97% with open non ported new FD3S housings.

Stock lower manifold: 92% loss of 8%

with dynamic chamber: 89% loss of 11%

Modified lower manifold: 97% loss of 3%

with dynamic chamber: 93% loss of 7%

These are only the first tests on this manifold and by the results found, it is optimistic that further improvements can be made. Even so 6 to 8% with an affordable price tag right now looks very feasible.

Please email for more information and to get on a mailing list so you can be notified when the new findings are ready. email azrotor@rotaryresponse.com subject: FD3S INTAKE

Air flow tests on modified housings are also showing improvements.

As it shows now a 15% to 20% increase overall in air flow seems very obtainable

Granted Mazda has made this powerplant very efficient. Nothing like the earlier motors. Especially the hard to flow six-port motors. So any improvements now are going to be small. It is when you add up all the 5%'s here and 7%'s there that we are seeing excellent results. We have a test car on the street now. Images to be posted soon.

1993 R1 modified induction, cleaned up ports in housings,clean up oil system ports, PFS intercooler, intake, silencer, Bonez downpipe, PFS engine management system, CenterforceII, Jacob's wires, Redline water wetter and SI1, Redline 2-cycle race oil added to fuel. All stock otherwise. But from the short time on the road it has shown that we will have to be doing some suspension work to handle it. Otherwise, driveablilty is excellent.

Turbo lag- doesn't happen. Smooth through all transitions.

This car is emissions legal, fast, and fun to drive.

September 17, 2004

jimlab

A lot of people use or do things that sound good without proof that they're actually necessary...

Kento

So solly, my bad.

GoodfellaFD3S

iTrader: (213)

So, what have we learned in the last 5 years?

Tim Benton

iTrader: (1)

it's still fun to argue with Lebreck just for entertainment value?

Tim

Monkman33

iTrader: (28)

We have learned that the flow imbalance between the front and rear rotor is definitely noticable.

Example A: Bone stock engine, 102k miles, injectors pulled and tested, not perfect but very close to each other, so it wasn't an injector issue.





I couldn't get a good picture inside the good rotor, but it is not caked at all, just a thin black layer.

gracer7-rx7

iTrader: (16)

Can that be tuned out?

The only thing that I can share is that you can visually see the difference in flow of the LIM runners if you run a strong stream of water from a hose through it. The flow of water on the front and rear runner looks a lot different. I noticed this as I was cleaning a spare LIM.

I pm'ed howard to try and get some info on the porting he did to his stock LIM but haven't heard back yet. Wish I could have done something about this but I don't know how to address this issue.

Monkman33

iTrader: (28)

The Excessive/GZ LIM addresses the flow imbalance issue. Quite possibly the easiest fix, but not the cheapest. Would then need to get a different oil filler neck to make up for the forward placement of the UIM. Also, IC piping will be affected too.

The only way to tune it out would be to run an AMS that allows you to tune each rotor individually.

The other thing to keep in mind is that one rotor is leaner than the other in low rpm conditions, but then that same rotor will run richer than the other in high rpm conditions. So you have a flip flop there that you would have to tune out. At that point, I would want to have a data logged EGT right off of each rotor's exhaust port, and would also want some way of balancing flow. I know that Pineapple made a prototype flow balancer at one point. I have one of the 5 they made sitting in my garage, waiting for me to send my new engine out to pineapple for porting and such.

The common method for keeping this safe is to tune for the leanest rotor at all times, which means that one rotor will always be running richer (carbon buildup)

A very nice remedy to this entire carbon problem is water injection. I personally think some sort of auxiliary injection is a must-have for a rotary anyways, but it could be the easiest way to run slightly rich, without the carbon buildup, and thus not need to have the gz lim or port your factory one.

Lots of ways to skin a cat, as long as you come out of it with a skinned cat and 10 fingers... you're good to go.

GoodfellaFD3S

iTrader: (213)

Monkman, that's freaking insane.....I've never seen that before. I have seen a motor severely carboned up (it blew as a result) but both rotors were equally bad. I wonder if something else was going on there.

Alberto, the GZ LIM can be used with stock twins with a little help from a die grinder, but you lose all the emissions and seq nipples, so I guess it wouldn't work for your specific case.

djseven

iTrader: (56)

Something else was definitely going on there I have torn down several 80-100k fd blocks and they looked nothing like that.

Monkman33

iTrader: (28)

don't get me wrong, both rotors had carbon build up, just one was much worse and this engine was babied for most of its life.

Let me add a correction to my original post:

They were both caked. just one was worse to the point of flaking off.

You know, I am wondering if I had full spark with this engine. It would definitely explain the incomplete burn if one rotor had better ignition than the other.

djseven

iTrader: (56)

You are right, there is usually a little more carbon built up in the front rotor, I am not debating that. However, I have never seen any results even close to what was pictured. You can definitely tell you had a fuel/spark/oil issue seeing how black/carboned the exhaust sleeve was in the picture. I still dont think anyone has found the limits of the stock manifolds, I think the limiting factor is finding a way to get enough fuel in the engine. I dont think we have even found the limits of the stock ports yet, recently the 700rwhp mark was cracked on a completely stock engine from mazda.

We have mazda setting us back years with the side port exhaust and higher compression on the new renesis(setting us back in terms of performance world) while there are only a small amount of shops out there still R&Ding with the rotary engine. I think we will continue to see big increases in power output and hopefully reliability at higher levels in the coming years. Remember, back in 2005-2006 it was a big deal to hit the 450rwhp mark, now days its nothing if you arent doing that on pump gas and low boost

Dudemaaanownsanrx7

iTrader: (23)

There was someone that posted several months back about a custom manifold he made with a large bore single butterfly throttle body, seems like he picked up like 50 hp. I would have to find it again to see the complete details of it all, he may have done some other changes at the same time.

Anything that can make more power at lower boost levels seems like an advantage to me, although usually there is a trade off somewhere, usually a sacrifice in the areas a street car drives in.

While 700 hp has been done on the stock ports, a little bit of lag could be reduced while making 700 at a lower boost level by porting the engine. It all comes down to what the car is being used for and what sacrifices a person is willing to accept to make certain gains.

Monkman33

iTrader: (28)

I have seen Mazda documents that showed how the stock uim is designed using a theory of pulse wave balancing. That is why the horse-shoe shape is used.

But this has nothing to do with maximum horsepower limits. I would guess that you would start getting more power from a different UIM as low as 400 hp, however, it would probably sacrifice a small amount of low end if you are designing a manifold for peak power.

Its always going to be a give and take.