Bigmotoxer

Jeff thanks for jumping in, I have studied the dilifidis and seen lots of threads on it(I seen a pic of yours I believe not too long ago). Anyway yes building first, installing, get tuned and go from there w/ignition.
I have access to a good body complete w/panels, dash, steering, glass, doors, harness', ect. and will probably build another 7 to put this engine in. I wanna aquire all the engine parts first$$$(including exhaust/intake), and all the drive-train, ect then build the engine(My partner Bill will probably help me build this, he's 68 and been working rotory's since they were introduced so I know it'll be done right, this is a guy that can build a 626 in original form from thin air in about 5 days, it's the damndest thing I've ever seen! Only problem is he hates mods, he loves original equipment only but I can persuade him this once), this will give me the extreme motivation I'll need to then build the car(paint, suspension, brakes, electrical, lamps,ect), drop in the engine, fine-tune and then finally the interior and some sweet wheels. So don't be surprised if I PM you guys up on a tech question or two...yes you Jeff, Blake, Doc, Trochoid, Wacky(even as grumpy as he is,lol), Carl, ect.

Blake, I would be willing to test that sweet 4-port out for you, if you could first learn me the difference between IDA and IDF throttle body How much $$ did you say you have in that build, let me re-phrase= how much $$ would it cost me to build that precisely?
Here's the deal, I checked today and I can aquire an SE13b w/29,000 original miles(it was a wrecked car) so I was set on the 4-port but now I'm tossed between the 6-port and the 4-port. And now I want the s5 stuff, hardened gears, OP mods I guess it would come down to a few things= "cost" AND "which would be the least problematic" AND "which has the best hp potential NA" AND "which would be best if I ever decided to go turbo in the future".
If I build a 6-port I'm still a little confused on what you guys mean by "using the appropriate Fuel injection system for whether you go with the S4 or the S5 set up"? how many options are there? I've been reading at NoPistons also but when I get to where I need to be it's all like " LIM dilifidis OP S-AFC P/P AF FP nitrided OMP NA IDA IDF...oh wait that's this site too,lol. I've searched for the words way back and find out, like nitrided, dilifidis and common sense tells me some of them like Air-Fuel, Fuel-Pump ect....but when you do a search on IDA or IDF or some that I can't re-call right now, it says "sorry no matches were found", I'm not dumb but boy does it ever help to make you feel that way. I vote we have an abbreviation decipherator at the top
Anyway going over my notes here, I have the 4-port built already(in my head), just need to spend some $. As far as the 6-port what would you use for intake? and fuel delivery(specifically?)? Would I need to use an SE wiring harness for the F.I.(cause I got one) or what about carburetion? and on both 4 & 6 port should I use an additional oil cooler(I think I can get a 2nd gen fairly cheap from my partner)? And radiator size(core's?)3?
I just wrote a book, look at that! Sorry if any of these questions are repetative or ,well, less than brilliant.

Blake

IDA and IDF are both Weber 2-barrel downdraft carbs. The IDF has closer bore spacing, so the flange is different (narrower). The throttle bodies I have are based on the Weber carbs, using matching flanges and bore spacing, each requiring a specific manifold. However, they both have 50mm throttle plates, so there is no real practical difference. In other words, they are the same but different. All it means is that the IDA throttle body needs an IDA manifold and the IDF throttle body needs an IDF manifold.

Oh boy, I really try to live in denial when doing a project for myself. To do this for a customer would be rather costly, I am afraid. The basic rebuild would be about $3000, with new rotor housings (in this case, I re-used some cherry old-school housings from the original core I have been sitting on for about 4 or 5 years, but we only use new housings on customer motors). I paid $200 for the original core, way back when. Medium/Large Streetport: $450. Oil Mods: $240. I also lapped and re-nitrided the plates, so that's about another $500. I only paid $200 for the S5 core from which I got the rotating assembly, but I had the labor to pull the engine and tear it down... There is also the painting, HD water seals, FD stationary gears and a few other misc things, but it's safe to say that a customer would be looking at between $4,500 and $5,000.

You get used to the abbreviations. As for S4 & S5 Fuel Injection, I'm not sure what your question is. The stock systems are very different because the S5 has more advanced engine managment, including a seriously space age stepper-controlled oil Metering Pump. A S-AFC is often used as a piggyback to the stock ECU just to lean out the mixture because the stock NAs run quite rich, particularly when making better-than-stock power due to an exhaust upgrade. The aftermarket programmable fuel injection systems are a whole 'nuther ballgame. My preference is for the Electromotive TEC III, but that is a pricy system. Haltech and Microtech are so-so, in my opinion (work okay but have crappy software and usually problems with tuning hickups that can't always be worked-around). MoTeC, of course, is the absolute Gold Standard of programmable fuel injection, but the cost of the newer systems is astronomical...MoTeC is mainly used in professional racing, where the cost is not an issue. I have an older MoTeC with a hand controller that is very slick and works great but, being so old, it wasn't designed to do rotary ignition. That just means I would need to keep my distributor. That's all I was talking about before.

Blake

By the way, here is what that engine looked like before I cleaned it up:

Bigmotoxer

I'm back thanks for the info, again. I work all day and don't get home sometimes until 7-8-9-10 pm pulling 7 parts cleaning them, shipping them, learning piece by piece the part #'s of the 1st gens, Bill has part #'s coming out of my, um, ears but to me is a valuable thing to know/learn, but also manning the computer and phone calls, although we just sell new and used parts(so we don't deal w/mods and too many retarded question) so you should know how it is (I don't know how some of you more popular buisness' handle it!). Anyway this leaves me dealing w/stock parts and stock re-builds, w/stock part #'s and it really is teaching me nothing for mods or any combo of mods and Bill don't even like to talk mods he gets all grumpy and says "they built the car like they built the car for a reason, I don't even wanna discuss modifications!" lol I mentioned aftermarket wheels-tires the today and he flipped, He's a good guy though, reminds me of my grandfather, but after all this it leaves me little time to research but I do stay up until 2-3 in the a.m. most nights reading. Ok so you guys are all I have for mods and I definately know the difference in IDA/IDF now, thanks.
As far as the F.I. I was just wondering what options were available for 6-port other than stock EFI. but I totally got it now w/your "stock systems different for the S5 it has more advanced engine managment, space age stepper-controlled oil Metering Pump... S-AFC being used as a piggyback to the stock ECU to lean out the mixture on the stock NA's. Aftermarket programmable fuel injection systems= Electromotive TEC III(pricey). Haltech and Microtech are so-so. MoTeC= Best but $$$$$$...cool.
I think i wanna build a 4-port myself before trying to conquer the 6-port F.I. and spend the extra $$$ for the programmers because I know me I'll end up buying the best and put myself in the poor-house. But w/Bills help we can slowly but surely get it build on spare time and be confident that it's right...and I know if I aquired all the parts, and then could pay someone to do my porting, lapping/re-nitride my plates(if you think it's necessary...I'll talk w/you about that), purchase oil mods,and what ever small things I may need(like doing some more reading on stationary gears and water seals(HD water seals? hmm) then Bill can help me get it assembled and get it right...(he's built 100's of rotaries in the past 20 years...just not modified ones).
So here goes=
You said you use some cherry old school housings? I have an RX4 w/10,000 miles on engine...it was a propane operated engine(never seen one of those before), an old mechanic dude built it and then died so Bill got it cheap from his family. Also have a 20,000+ miles SE 13b and another 13b w/29,000 miles before it was wrecked.
MY QUESTION= SHOULD I use one of these to get my housings/rotors or should I buy new housings/rotors? AND where/what the heck does s5 rotary assemblies come out of? s4 come out of? (these are my last stupid questions, promise!) I thought 13 housings were 13 housing 85 and prior? A good clean/smooth/low-mileage housing is primo right?
NEXT= Use 12a tranny or 13b tranny? I know the 13b's are lower geared, which should I use? w/the 4-port? (I hate how the SE tranny zoom/zing and your redlined in 1st gear traveling a total of 1/2 mile-an-hour)
NEXT= When I talked to Bill about building a 13b 4-port(using 12a irons), he laughed and said why not just build/drop in a 13b,...he didn't understand the principal of using the 12a irons, SO tell me short and sweet= Why do we use 12a irons to make a 4-port so that I can short and sweetly explain it to Bill(I told him it had to do w/the intake.
Lastly= Bill says he has 2-3 Japan spec engines, opposed to US spec, what does that mean to you? what's better, what's worse, and why?
Thanks for all the help/info and thanks for no-one busting me out like "do a search you freakin' freak !" And let me know if you can do some porting for me and maybe help me get my hands on some proper parts/services.
LaterZ, Russ

trochoid

iTrader: (6)

Many of the newer members ask short questions and don't provide enough info to even understand the question, you write a novella, lol. I'll hit a few of them.

One uses 12A irons to build pre-86 4-port 13Bs because the 74-78 irons are hard to find and usually not in that good of condition. They were also not nitrided, iirc. The 12A irons also have better ports and all 13Bs made from 84 and up are either 6-port NAs or 4-port turbos, disregarding the RX8 Renesis engine. Using the 12A irons allows for larger/better porting than one can achieve on the 6-port irons.

The housings in the low mileage engines you listed should all be in very good condition. Almost a shame to tear down the engines for them. New housings are not cheap, use the freebies and spend the extra cash elsewhere.

S1-S?, the S stands for Series and is based on the years each one was produced and infers minor/major changes to the body and/or mechanicals You get to look that one up. It's basic info any rotary owner should know and by finding it, you will learn much more than you are looking for.

USDM vs JDM. Yes, there are some differences, mostly minor and since they're all produced by Mazda at the Hiroshima plant, quality is the same. Many of the JDM engines had a slightly higher hp rating than the USDM versions, mostly due to our emission requirements.

Blake

Yes, the RX-7 side housings (aka "plates") were nitrided surface hardened, while the earlier stuff was just hard as a rock all the way through. We like the nitrided plates because not only is the surface a bit tougher but the innards are way softer, so porting is easier. I also like the "tall port" center plates, which are designed with the same runner volume as the short but wider runners in the end plates, which works well with the "square timing" (identical primary and secondary ports) port aperture setup. While you are able to make a 4-port 13B using the later (86+) turbo housings with the higher compression NA rotors, there are no manifolds to fit that combo-burrito, it doesn't really provide any great advantages, and you can use those same high-compression rotors with the earlier stuff just as easily.

With the 4-port NA combos requiring so much effort, you might think there is a good reason to do it, but it's just not the case IMHO. If you have the parts sitting in your lap, as I did, why not? But if you need to scrounge for them, I would highly suggest that you just go 6-port NA. I wouldn't cross the street to do a 4-port NA, let alone really work to collect and referbish the parts. Also, in addition to all the aftermarket 6-port manifolds (IDA, DCO, etc.), Mazda did a *great* job with the intake manifolds and throttlebodies starting in 86. If you can keep them, you really will have a great all-around setup.

Bigmotoxer

Yeah it would be a shame to tear down a 20k SE 13b. The RX-4 13b has very good irons, housings, ect(low miles) but has "automobiles" stamped on it so the ports suck, correct? Ok so reading info, I'm thinking of using this RX-4's housings, rotors, shaft and then using JDM irons...
1.) BUT would it benefit me to use the JDM irons over the USDM irons seeing how I'll be porting anyway?
2.) Will the stock intake on the RX-4 after "porting" be good or will RB/ect have much better flow?
3.) As far as nitrided goes, that only applies to the irons correct? And if I used VERY low milage 12a irons they're nitrided from factory correct? Or would you recommend getting them re-done.
4.) hardened stationary gears? Is this a process that can be done to rx-4 stationary gears?
5.) 3 window bearings...benefit?
6.) What carb would be large enough cfm but not over-kill?
(I tried to keep it short for you Trochoid )thanks guys.

rotorymanincraig

I thought it was STAND ALONE FUEL CONTROLLER.

monkhommey

this....


became that?



i didnt read the whole post because im at work.. so sorry if this is redudant.

how did you get that thing so clean.. i would probably eat my lunch off that thing..

im starting my first rebuild and i scrubbed my housings and irons for about 4 hours in parts cleaner and they are still rather dirty.. i am thing of taking them to a professional if i cant get them a little cleaner. i was also planing on painting them up all pretty like, so should i just do paint over the left over grim?

glewsRx

iTrader: (1)

Dont mind this guy, he's just stealing a thread.

Blake

Yes, the first is the 'before' and the second is the 'after'. Same plates and rotor housings. We start by cleaning the parts in a hot water parts washer, then media blasting the exterior surfaces. From there, paint prep just means a final de-greasing with alcohol before spraying. You absolutley cannot just paint over remaining grime and have it (a) look good and (b) last.

Bigmotoxer

hmm, I might give you a call Blake, I gotta figure this out first
Thanks bro