20b advice

[warwickben]

hey guys, iam really thinking about trying to find a 20b and trans to put in to my sa. if i do, do it id go na at frist.

i was wondering what i would have to do to put a carb on it. i know different custom intake but besides that what would i have to do to the motor to run it with out a ecu. i know it mite sound silly but iam a 12a guy.

[Herblenny]

There is quite a bit for you to run it carb'd... First, you would have to rebuild the engine and use higher compression rotors... Then track down a distributor for 20B (kind of hard)... Then setting up the 3 rotor carb..

I'm guessing around 5k-10K job.

[jtbshaw]

Twin Weber IDAs FTW!

[warwickben]

i was going to boost it if i did go with a 20b.

but my main thing i could not get my head around was the distributor. i wish i new about ecu's ect other wise id go that way.

heck i wish i could find a place that sells the motor, trans, ecu ect in stead of having to buy a whole clip id just run that stock in my sa till i learned how to tune a ecu. all i have been able to find on the net is complete motors and trans without the ecu or complete front clips with the ecu

nolimitind i would probably do that or twin o.e.r side drafts.

[jtbshaw]

There were two complete units for sale on ebay today for $4500.....like this one:

http://cgi.ebay.com/ebaymotors/Parts-Accessories___JDM-20B-3-Rotor-Cosmo-RX7-mazda-20B-Turbo-20B-3-Rotor_W0QQitemZ380044938784QQddnZPartsQ20Q26Q20Acc essoriesQQddiZ2811QQcmdZViewItem?hash=item38004493 8784&_trksid=p3286.m14.l1318

[jtbshaw]

Here's the other one:

http://cgi.ebay.com/ebaymotors/Parts-Accessories___JDM-Mazda-Cosmo-20B-3-Rotor-Engine-Rx7-Speed-Twin-Turbo_W0QQitemZ370068220027QQddnZPartsQ20Q26Q20Acc essoriesQQddiZ2811QQcmdZViewItem?hash=item37006822 0027&_trksid=p3286.m14.l1318

[warwickben]

thanks, ok ok you guys are twisting my arm now making me want to go 20b lol.

i guess ill just save up and do it. keep it stock till i under stand tunning. heck even if i went with turboing my 12a or a TII swap it would cost me about the same.

[Herblenny]

Ok, you start the thread with this
hey guys, iam really thinking about trying to find a 20b and trans to put in to my sa. if i do, do it id go na at frist.

Now you say this??
i was going to boost it if i did go with a 20b.


20B project isn't for someone with light pocket.. Trust me, I have 2 of them and to do it right, I'm planning to drop some serious money. Not only that, I been talking and searching for past 2-3 years. I'm finally getting the short block completely built this summer/fall... if I'm lucky.

This is what I say to people... And i'm sure others might agree... Think about why you want to do this.. If your goal is street drive your car and make 300-400, then save your money and spend it somewhere else... If you tried different things and now 20B is the only thing left for you to do, GO for it!! Drop some serious cash and do it right.... Otherwise, its not worth tempting.... there are far better ways to spend your money then on 20B and half ass build it so you could say you have a 3 rotor in it..

[85rx-7gsl-se]

In others words, if you have to ask how much it costs to do a 20B right, you can't afford it :)

[jtbshaw]

Well said, 85SE!

Phil is right. In my case, I've been working on these things since the mid 80s. I've had every combination of 12As and 13Bs, except a peripheral port. I've wanted to go 20B for a while now, and Phil can even vouch for me on that. I began talking with him over 2 years ago about a 3 rotor setup and I still haven't pulled the trigger on the project yet. A 3 rotor setup is a huge undertaking, especially if you don't understand how everything works with each other (and part of that is tuning).

As Phil also mentioned, you may want to go a different route. You stated that for about the same $$$ as those ebay auctions I showed you, you would spend in turbo'ing a 12A or 13B. There's many different ways to go about turbo'ing a 2 rotor without having to spend $5k. Yes, you will spend a couple of grand, but not all of $5k.

[Herblenny]

I hear ya Todd!! You are the type of person, I want to see 3 rotor rotary car..

About my comment above..
Don't get me wrong... I'm sure almost all of us on this forum would LOVE to go 3 rotor.. I think in some ways its a wet dream.... LOL!

But the thing is that, I've heard and seen young kids talk about doing 3 rotors or lying about having one in their car... When I start to ask specific questions..

I'm not trying to kill anyone's dream.. And I guess I'll be pissed to if someone killed mine:) but realistically, its not as easy as some think.... Sure, you might get it in, go na or turbo, and it will move... But is that all you look for in building a car????

The thing i starting to realize is its SO much harder to build all around car. Car that you could take it to a 12 turn track, run the drag, and drive on the street without killing your back... Its so much easier to build a car to do one thing... but to do all, it take time and learning...

I on the other hand from the start told everyone that my 20B project is for a show... But I also believe just show doesn't mean it couldnt to other things I've mentioned above..

[To_Slow]

After building 3 turn key 3 rotors, 2 for my customers and one for me.

I can tell you its not cheap. Right now i have over 30k in my latest 3 rotor set up and its not even in the car.

So if you have the cash, do it if you have to save up for it there are better things to do with you time and money.

Hope that helps

[warwickben]

thanks for the advice guys. the comment i made about starting na then the thing about turbo is my fault i should of explain a little better.

the na comment what i should of said is after i go tho all the work of just getting it in the car and if i could convert it to carb to see if i could get it run right on a carb. then i would go turbo. if i couldn't go carb with it most likely id just keep it stock and be happy with it till i fully understand how to tune the ecu's ect.

sorry if i pissed any one off i did not mean to. i just wanted to know info. if i do deiced to go 20b it wount be for a few year's. id probly get the motor and slowly build it over years when i have money.

i deiced for now ill just stay with a 2 rotor

[BLK FC3S]

It's less work and less money to get a 20b to run turbo'd than setup a whole N/A 20b. It involves rebuilding the motor with different rotors, custom manifolds, replumbing just about everything. Why bother if you're going to eventually go turbo anyways. What I did is just start out with the motor and get it running good with the twins before going all out. When you get it running good and all the bugs fixed with the stock motor, then you can start going big.
I see too many people dump tons of cash into a big project either to find out they didn't have too or that they still can't get the thing to run right after hours of tuning. I don't know the exact percentages, but most projects get scrapped before they even start.
If you do go through with the swap, think about how much money you think you're going to spend and then triple it. Thats how much you should have in your bank before you even pull so much as a spark plug wire off your existing motor.

[vincentrx7]

This conversation is exactly why so many people have 3 rotor projects and only a few have running cars. On the other hand, I absolutely love mine. I did a 2 mile road course, an autocross and tomorrow night I'm going to an 1/8 mile drag strip. It is way more car than I can drive to its potential...but I was looking for a rotary with good hp that I could make reliable. I think I accomplished that...at least the engine anyway. I'm trying to beef up the drivetrain now....more money....and I need a 99 spec front end and a vented hood to help with the water temps.
I think you made a wise choice going with a 2 rotor.

[warwickben]

yeah iam going on to go with rebuilding my motor and turboing it. iam just having trouble picking the right turbo. iam not looking for insane numbers. just 8-10 psi since this is my summer car. i was told a t04b would be a good turbo for what i want . but then i go online and starting looking at them and they have like all these differnt options for trim ect ect. so i dont know which one to get.

my other car that me and a buddy own a 1984 rs turbo capri is the high horse power car well drive one in a while. 20-25 psi on a 2.3 motor should be fun.

[Whizbang]

It's less work and less money to get a 20b to run turbo'd than setup a whole N/A 20b. It involves rebuilding the motor with different rotors, custom manifolds, replumbing just about everything. Why bother if you're going to eventually go turbo anyways. What I did is just start out with the motor and get it running good with the twins before going all out. When you get it running good and all the bugs fixed with the stock motor, then you can start going big.
I see too many people dump tons of cash into a big project either to find out they didn't have too or that they still can't get the thing to run right after hours of tuning. I don't know the exact percentages, but most projects get scrapped before they even start.
If you do go through with the swap, think about how much money you think you're going to spend and then triple it. Thats how much you should have in your bank before you even pull so much as a spark plug wire off your existing motor.

while i do agree that the swap is expensive i do believe its cheaper than running a turbocharger, as long as we are talking EFI here. You don't need custom manifolds or things reworked. Most custom part of it would be the header. The rotor setup may be most you have to look into functionally, and its mostly in regards to balance.

As Logan, he has a very lovely 20b(un)T in his FD.

[Whizbang]

my other car that me and a buddy own a 1984 rs turbo capri is the high horse power car well drive one in a while. 20-25 psi on a 2.3 motor should be fun.

i have a 2.3T sitting in my shop collecting dust. Just not sure what i want to do with it.

[warwickben]

have you heard of the volvo head swap. makes it a dohc. the na 2.3 put out around 100 bhp. the turbo put out around 200 to 220 bhp depending on the year but all ways more power then the 5.0 from the same year. if you put the volvo head on a stock na motor you make about 200 hp. there is a few people who did that instead of going turbo on the mustang sites i go to. on a stock turbo block with stock boost most people make about 280 to 300. you install the volvo head you need to weld a block of metal on the back side of the head. run one external oil line and mod the timing belt tensioner.

you could try to find the after market big bore head that they stop making. or if you want to spend a crap load on just a head that bolts on you have elsslinger(sp?)

if you need help getting a rebuilt turbo 2.3 head i can help you get one from under 200 plus shipping. my step dads work sells so much product there cost is so cheap, and he only has to pay cost for parts.(the sell to fleets and auto shops like napa)

the 2.3 block is pretty dam strong and theres alot of guys making close to 700 hp with it.
if you need any advice hit me up.

pics of the car can bee seen here. takes a bit to load. the kid i own the car with is the red head hes kinda picture happy lol.
http://gallery.mac.com/whytei#gallery

before
http://gallery.mac.com/whytei/100016/Before-201/web.jpg
after we rebuilt it and painted ect ect. you have no idea how hard it was to sand the paint off where we left it metal since masking with high temp paint sucks.
http://gallery.mac.com/whytei/100016/P3180022.jpg?derivative=medium&source=web.jpg&type=medium&ver=12160154030003


any one looking to carb a 20b rotary shack sells a dizzy for that.

[Whizbang]

i have thought about the 16v 2.3 swap, but first and foremost the engine needs a home. I may just swap it into a black FB i have, but the issue i have is the transmission selection sucks.

[warwickben]

i know what you mean about trans. we have a weird stock clutch setup on the stock 5 speed. we had to rebuild it and went to 5 ford dealers and 3 auto parts stores and every time they brought up the parts list you know a simple black and white drawing of it with part numbers ect. it was a different setup (84 rs turbo capri fox body).
we dont have this setup on our car. but this is what they all said we had.
http://econtent.autozone.com:24991/znetrgs/repair_guide_content/en_us/images/0900c152/80/04/e2/ef/small/0900c1528004e2ef.jpg
the cable mounted in a different spot then there was a rod sticking out of the side of the trans, that had a bracket on it that rotates. the clutch cable end hooks in to that then on the other side of the bracket is a hole and a dog bone connects to the clutch fork.
we have a push style clutch not a pull yet ford told us where wroung lol.sorry hard to explain . we had to custom make the bracket since the bearing where gone and we could not get new ones.

i dont know why but www.stinger-performance.com is not working. they have a adpater plate to bolt any t 5 trans up to the 2.3 bell houseing. best bet is the t-5 used in cobras ect.

we plan to run the stock rebuilt trans till it blows. the only thing we have to worry is breaking the tail shaft off. the stock trans is not rated that high but there is people who have 700hp cars that wheelie that havnet broken them so go figure.

if you do re build the motor and have the 4 inline intake get a 4 square pattern lower iintake.gut/ knife edge the lower so the center is a point, then get a 65mm throttle body.
gut the upper intake which is a bitch and not worth it if you have spare steel and a mig welder. do like we did we made a custom upper intake. its more or less a spacer. the throttle body is now face up and down instead of being side ways. this works out since if you gut/knife edge port what ever you want to call it the lower you have to gut port the upper. the problem with gutting porting the up since its a 90deg elbow 2 of the ports wount get as much air flow. since we made a riser and the throttle body sits 3 inches above the lower on center all 4 ports get the same amount of air. sorry if this is confusing.

or you could be bad ass and get these.
http://www.esslingeracing.com/catalog/page16.pdf
http://www.esslingeracing.com/catalog/page15.pdf
i tried to talk my buddy into going with the side draft webber turboed but he thought it be to hard to tune. i figured it be cheaper then efi.

[Whizbang]

i just hate T5 transmissions. Plus they are quite a bit more than the engine itself....

[warwickben]

true true. i forget what the rebuild kit cost us but it wasnt that much .
where looked in to getting the t-5 from the 03 cobra . its like a few grand new but we could of got it 200 from a junk yard. the only problem some one picked it up befor we got there so we have to wait for another mustang to get wrecked.

i thought about putting a 2.3 in my car when we picked up a 2.3 block from a b2300. but i decied to keep a wankel in it.

[Whizbang]

yea my biggest thing is i have tons and tons of parts for the rotary, and JUST this engine sitting in the corner. So its would be much easier to do a nice n/a 13b 4 port FB since i just have everything laying around.

[rx8man]

Ok, you start the thread with this


Now you say this??


20B project isn't for someone with light pocket.. Trust me, I have 2 of them and to do it right, I'm planning to drop some serious money. Not only that, I been talking and searching for past 2-3 years. I'm finally getting the short block completely built this summer/fall... if I'm lucky.

This is what I say to people... And i'm sure others might agree... Think about why you want to do this.. If your goal is street drive your car and make 300-400, then save your money and spend it somewhere else... If you tried different things and now 20B is the only thing left for you to do, GO for it!! Drop some serious cash and do it right.... Otherwise, its not worth tempting.... there are far better ways to spend your money then on 20B and half ass build it so you could say you have a 3 rotor in it..

What has been said above, I totally Agree With, How Much do you want to spend???? Coz the 20b is a money pit.

I did put a 20b in a series 4 convertable, I Do regret selling it, but life goes on ...lol..
First-- Unless you have a know how to nut out engineering type problems, Don't try doing it yourself, But if you are going to Pay someone to do it-- you will spend $$,$$$-- case of note-- I did everthing my self-- It cost me $10,000, a guy who owed a bussness where I use to live, spent around $30,000 plus, GAVE UP, NEVER GOT IT RUNNING.
You will need-- new engine mounts, a ECU (mircotech ltx12s is what I used), are you going single, or using the little twin turbos-- if you are using the twins-- it is cheaper--but a bit of work has to be done on the Manifolds, Gearbox, drive Shaft, coils (you will need 6 of them), Radiator, intercooler, etc, etc
Ita a Big Project, I wouldn't even think about it unless you have a spare $15 k sitting around, and the motor you get, Will prob. need a re-build.

Don't get me wrong, the 20b is (in my opinion) the best rotor, and I would love to get another one to drop in my rx8, but like I said above--its a money pit.

[StumpDrummer]

Im just waiting on Dan to build a 4 rotor monster !!
Id love to see it in my 80-7

[gmonsen]

I would just do what others down under have don e and that's just drop in the stock twin turbo'd 20b with stock ecu and drive that. Light tuning get's you 300 whp and a LOT of torque.

Gordon