i am wanting to sell my FD and take on a FC project and run a 20B NA with the stock 9.0 rotors, to maybe replace them with the 9.7 rotors and streetport it. My main goal is to make a cool NA daily driver that i can fillup with 87 octane and still make over 220whp with... if this project actually happens, heres a list of things i'd be using:

cheap s4 TII or maybe s5 TII with a blown motor
20b, no turbos, stock 9.0:1 rotors
TII flywheel
TII stock clutch
TII drivetrain
FC water pump housing/alternator/pulleys/belts
k2rd(or fc3s.org?) motor mounts
koyo radiator and flexalite fans
microtech EMS, but here's my question: do i really need timing split? i could save alot of money getting a haltech e6k or something a little lower-end, but it wont be able to control the split for 3 rotors... is it worth it (when talking strictly in terms of natural aspiration) to spend the extra money for the 3rotor split? the price difference between then microtech lt12s and the lt8s is like 400 bucks
also, not sure what i'd need to do about the coils. maybe use 3 leading FC coils if theres no timing split... or 6 stock FC trailing coils if theres a split, or maybe the bosch coils? not sure here.

to sum it all up:
1. how much power can you make with a stock block 20b NA?
2. is it worth it to spend the extra money on the EMS for timing split?
3. and other random things i should look into?

 

First off, you cant use a TII flywheel for the 20B; its counterweighted differently. On an n/a setup you can get away with locked timing (0 split) and use those leading coils if you wish (what i'm doing currently). If you want to look into a boosted application in the future then you should look into a different ECU that will support split on a 3 rotor, such as the E11. You should make around 230whp on a n/a setup with stock ports and rotors. This is just some of the first things you'll have to look into, it is a very involved swap and will take alot more time and money than you originally planned on. There are so many little things that you will need to look into such as: dual oil coolers, oil cooler lines, header, sway bar, different radiator (that koyo wont be up to the task), and the list goes on. You really have to sit down and plan this completely out.

 

if that is your goal... then a basic LS1 swap might be a LOT of fun for you and WAY easier on your wallet than a 20b swap. not to mention its a much less involved way to get 300whp AND have a sixspeed AND have barely any change in weight. alas, the LS1 does require 91 octane. I know this is a 20b forum and I dont want to **** anyone off here, it was just a quick suggestion. there are many merits to the LS1 setup, especially in an FC, its such a simple install and the motor is all metric and all aluminum, its a very nice package.

 

ahh yeah good point about the flywheel. i forgot the 20b MUST have its own original counterweight, so i guess that guarantees that you have to use an aftermarket flywheel...
also, about the dual oil coolers: the large FC oil cooler isnt up to the task? custom lines wouldnt be that big of a deal. and what radiator is totally better than the koyo in the aftermarket?

 

i wont be putting a v8 in an rx7

 

The koyo has been used successfully in a 20b swap. I also will attempt to use a fC oil cooler as it has a larger capaicty than even both R1-R2 oil coolers in the Fd. It doesn't matter the size of the heat exchangers but bigger does help. What matters most is how much air you can flow through them so they can do their job. That's why ducting is the biggest key in making that set-up work.

 

You I'm really curious to see the size of the factory 20b radiator in the Cosmo. Does anyone around here with a front clip have pics? I'm willing to bet that the factory radiator has a smaller capacity than the Koyo.

I know that Rotormotor had a front clip.

 

look at the 20b b2600 thread, thats a stock cosmo radiator in there. its tall and wide, but its thin. i forget how tall and wide, cause it was like 2+ years ago.

mazda seems to have gone to really wide, and thin radiators lately. the rx8 on is like 28-30" wide, while the sa/fb/fc/fd stuff like like 20"

 

I tried fitting it in there, it just wouldnt work.

 

20B10AE (I beleive is his username) was running into alot of cooling issues with his koyo. I beleive the dual coolers are nessisary if you plan to do any sort of road racing or autocross. Just gotta watch your oil and water temps.

 

unfortunatly i dont have the radiator anymore, and my HD crashed so i lost all my dissassembly pics of the front clip. it was sent to the junkyard a year or so ago along with most of the front clip (besides the motor of course). i can however tell you that the radiator WAS rather large (significantly taller and wider than the stock FD radiator). it was fitted with one large electric fan to augment the clutch fan that is fitted directly to the motor. the radiator was very thin though... at least as thin as the FD one and possibly more (maybe an inch or less). now, something that i DONT remember 100% was if that was strictly a coolant radiator, or if a portion of it was used to cool tranny fluid.... i seem to recall there being a separate transmission fluid cooler, so im going to assume it was just deticated to cooling engine coolant.

anyway to answer your question.... no i dont believe it would have had MORE sheer coolant capacity than say a KOYO... i could see it having equal to, or less than the capacity of the KOYO. but keep in mind, we're not comparing apples to apples. a larger and thinner radiator design would be more efficient for cooling purposes, as well as allowing more air flow through the radiator (increased air flow = increased cooling).

CCarlisi is working on a coustom rad. setup for an FD at the moment... hopefully he will post up some info on it or maybe he already has a thread... i forget. but what i DO remember is that its good for 700 HP, and he "Claims" it will fit.... but we'll see

-heath

 

Hi-comp rotors with a P-Port or at least full bridge is the only way I see going N/A with a 20b worth it.
You could get a dizzy from Mazdatrix and use a fuel only ecu.

Cooiling requirements for an n/a are going to be nowhere near what a turbo setup would need. With adequate ducting a koyo should be fine.

This place has some choice radiators for fc's.
http://www.awrracing.com/awr.html

 

ok that is good news. so the koyo will be fine, and the FC oil cooler will also be fine.

its not like i'm going to have a huge FMIC up front to block all the air-flow to the oil cooler and radiator... its NA. i'll even have a front lip and underbelly tray.

does anyone have any more input on the engine management? i'd hate to have to drop like 1400 bucks on an e11 when i can get the job done with an e6k or X with 3 FC leading coils...

 

are you sure about this? 230whp seems like alot for a stock block NA 20b... i wonder what it would do with the 9.7 rotors

 

Yes he's sure. Reted got 238 rwhp of a stock block 20b with 9:0 rotors. The only restriction is the factory intake manifold design. 9:7 rotors would indeed bump up the hp. Just not sure how much. 9:7 is also what I'm going to put into my 20b as well.

 

Sorry for taking so long, but I wanted to have the time to give you a thorough answer, and this weekend has been stupid. :P

We made *232* at the wheels on a DynoJet with our 20B.
I don't want to repeat myself, but the thread should be still in here.
The short block has never been opened up, so it's running the stock 9.0:1 rotors still in it - no porting.
A Haltech E6K current pushes the whole thing via a trio of stock FC leading coils (no split), but a Haltech E11V2 is in the wings to be installed soon.
The header is custom made; it's ugly, but it works.

Going with the 9.7:1 rotors should give you 5% to 10% on a WAG.
Did you see the other thread where they made 300+ with a custom intake???

Timing split depends on who you believe in and what you're going to do with the engine.
Some will argue you need the split to ward off detonation; I personally don't think this is the case, but it's nice to have control of it, since it's another dimension of tuning.
ANY 20B project is a major one, and expect to drop serious cash - $10k min with another $10k "just in case".
The price between an E6K / E6X versus an E11V2 is peanuts compared to the rest of the stuff you're going to have to pay for...
I would highly recommed going with the E11 once you got the money; the E6K is fine for now or for mild 20B turbo applications.

If you're going to street this thing, then drop-in aftermarket options are okay for cooling.
The stock oil cooler is okay if you're going to street it also.
Once you want to track it, the 20B heats up damn quick.
We're using an AFCO double-pass and dual Earls oil coolers on the car now, and temps are tamed on the race track no problem...still NA.

The owner just bought an ATC twin carbon clutch, and hopefully that'll hold off the transmission breaking for a few months.
That's a $1,800 clutch.
We *expect* to kill the trans and the rear diff.
OS Giken gear set will be ordered by the end of the year.


-Ted

 

what is all this "stuff" i'm going to have to pay for that i havent mentioned?

 

I really dont see the point in dropping all that money on a 20B swap for only 220rwhp. I know that you know you can do better than that with bolt ons on a Turbo2.. so why? I too am this close to yanking the REW from my FD for a N/A 20B, but I wont be happy with any less than ~350RWHP. Why do you want to pay thousands for 220? Even a blown 20B sells for at least $1500, then the costs of rebuild, porting, ECUs and all the hassle and headaches that will come with it. For decent power from a N/A you really need a custom intake also. Im sure Im not telling you anything you dont already know, could you just fill us in on why you want to go into all that for like 250HP?

 

its a bunch of little things. wiring, cooling hoses, bolts, nuts, hardware, fabrication (my rewelded twice t stat cover, was like $100ish, the first time, then $30-40 the second), exhaust.

plus some of this you get to do twice, cause the first time you put it together some things wont work right/well enough etc etc

 

You can't look at everything as what you can get for the money when investing on a project like this. Running the engine NA is only a starting point. Mods can always be done at a later time and on a timely manner. For some reason people on this forum seem to miss this logical approach. I replied as this will be my approach with my project. Once you get the engine in the car and running, you have won more than half the battle. You will also keep a hi interest in the project as it takes longer to finish since everything isn't done all at once.

 

me neither.
I guess you just want to keep busy.

man thats an assload of money for such little power.. and a LOT of time and effort to get it all together, wired up, well tuned and running cool.
I think youre crazy but, yeah, sure, the 20B looks cool.
anyhow, good luck.

 

Why do? Why not? Its the people who actually try out things that are outside most of everyone's "comfort zones"/reasoning that progress the development of things in this world today. The way I see it, he will virtually double the power that a stock port 13B N/A makes and still have roughly the same N/A reliability. We probably wouldn't even have rotaries if someone just straight up told Felix that his idea was pointless and actually convinced him. You LS1 guys wouldn't have LS1s in your car if SOMEONE didn't try it. Hell we wouldn't have computers, RX-7s or ANYTHING if people didn't step up to try something or just listened to what everyone else told them was a bad idea. It is his money afterall, not yours. You should try asking him HOW it should be done rather than WHY it should be done. Rock on Jacob.

 

I can understand the spirit of experimenting and trying new things, but not for the sake of how hard or crazy it is.

Im experimenting with a ford 2.3T based off of facts and reasonable expectations, such as cost effectiveness, parts availability and prices, the knowledge base in the enthusiast community, and reliability. Not emotional appeals to experimentation and emotional attacks against people who say its a bad idea and back up their criticism with facts.

Using buzzwords like "comfort zone" makes me want to ask you on a more personal level if youve attended any "seminars" or "workshops" modeled after EST, or just picked it up from someone who works in sales.

And, FYI, a 20B has 50% more displacement, not 100% more, you wont double power without porting and work on the intake and exhaust, and of course tuning - and a lot of the engine swaps are OTHER v8 engines, or v6s. Im using a 4banger!

 

A 20b has more torque than a 13b, and is far more driveable, eg--I can slug around as low as 25 mph in 5th, and still acc. away, go up hill in top (5th), etc ,but having said that I'm still running with the twin turbos--. I think you can make a lot more power out of a 13b, cheaper, but having had half a doz. 13bt's, when you start running big turbos & ports, ---my ones never lasted long, & was forever changing gear to keep the boost up.
Don't know what a N/A 20b would make (hp) or run like, would like to know, as I'm thinking of going down that path with one of my other 20b's
Just do a lot of homework on it, --good luck
1st pics--20b not long after been put in.
2nd pic--Eary bird 20b
3rd pic--new 20b from Mazda dealer, in box's, (cost twice as much than the early bird motor, & have yet to get a E-Shaft & put it together)

 

No sir, I've never attended a seminar or such. I think they'd be boring anyway. Its actually something learned from psychology and from my father. My whole thing is, this is a tech forum. The guy is clearly committed to what he wants to do with his car and everyone should support him and give him ideas to make it work as painless, and efficient, as possible, and not ask him "WHY this motor instead of this motor." Give him tech support not a bunch of off subject "why"s. I'm familiar with your general favor towards the 2.3T and would never ask you "why that motor instead of a LS1?" I'd ask you how do you plan to go about the swap or how you'll deal with a certain issue known to occur on a particular motor of choice. Everyone's car is their domain and no one else's............. I sound like such a nerd