I am getting ready to go single turbo power over the winter, among other things that I want to do to my FD. My car is already off of the road and I am about ready to start buying parts. But I just received my Options/Rx-7 Special video. Which has some sweet sevens on it. RE Ameyia(sp???) has a couple of cars on there. One of which is a Blue 3 Rotor car that has Weber?? carbs I believe, and it sounds like it has a bridge-port as well. Now what is your guys opinion on a 3 rotor bridge-ported, carburated, FD?? Think it may be dumb to carburate at 3 rotor?? I'm thinking it may be a more reliable alternative to a single turbo 13B FD. Or at least something different. I just love the way it sounded...

Oh yeah, another question, any guess-timates on how much you think it would cost to set up a carburated 20B in a FD?? And anyone know somebody besides RE who has done it??

Thanks all for your time, and please no flames...

 

I would if I had the $$ you get about 450-500 N/A power! lots of torque and it also makes your engine bay look soooo simple when it is carburated. I think going carb will also simplify the wiring. RE's GT car is 3 rotor N/A, Revolution also had one, and on one of the new options I saw a guy with a white FC that had it as well...

good luck finding a shop that will do this!

David

 

god damn thats a lot of power for N/A

 

Yeah I figured you wouldn't need to find a computer, so that would simplify it a bit, plus I figured it would be a much simpler system without the turbo stuff, and with out all of the wiring. Because I would take it that you would strip all the wiring off of the engine except like for the alternator, oil pressure sender, water temp sender, etc.. I would think it would be a bunch cheaper to set up too, compared to a turbo'd 20B

 

It would be about $20,000 USD if you did everything yourself (including a lot of fabrication), and up to $60,000 USD if you had a professional shop do it. Of course, that depends a lot on what kind of options you choose, as a GT-level (450hp) NA engine would tack on another $30,000 or so to the price tag. Yes, that's right, it would be MORE expensive than dropping the stock twin-turbo 20B (550hp potential) into your car. Nice try, though. However, I think that it would make a very interesting project, and yes, it would simplify the engine bay. I saw a really cool NA EFI 20B manifold on one of the Aussie? web sites, but I forgot the address.

If you are just looking for more HP, you may want to slap a nice single turbo setup on your 13BREW, and you could make the same peak 450HP as a GT-level NA 20B for under $20,000 in parts and labor.

For the carb issue, I think that it is "dumb" to put a carb on ANY engine that operates in a wide rpm range. Drag cars, airplanes, etc. may operate at a "constant" rpm and can use a carb just fine, but everything else is better off with EFI. While most carbs have only 1-3 points of tuning, most of the low-priced EMS units have 128-512. Also, if you price carbs and manifolds, you will see that they cost just as much as the low-price EMS units. IMO carbs are NOT easy to tune, especially multi-carb setups. After a tuning session with a Wolf3D, I quickly determined that I will never again have any use for a carb. BTW, you can download the Wolf manual and software and try it out yourself:
http://www.wolfems.com.au/images/W3dv3_0manual.pdf
http://www.wolfems.com.au/images/wmc.zip

 

I found the picture. IMO this would make a killer show car, not to mention a pretty fast ride. As you can see from the other pics on this site, EFI makes for just as clean an engine bay as a carb.


http://www.injectionperfection.com.au/

 

The Mazdatrix drag car has a bridge-ported 20B, and they were going to run a Holley Projection (programmable TBI setup) but that didn't work out so they stuffed a Dominator (1050cfm 4-barrel) carb on it. THAT worked out.

If you've never seen a Dominator in person... man, those things are HUGE.

 

The next mod in the works for Mazdatrix's drag car will be an Atkins supercharger with injection. But you didn't hear that from me.

 

The SCCA EMod autocross national champ uses a 20B (in a Bugeye ) with what looked like a Weber tripple downdraft that is used on the flat 6 Porsche motors. Here is a pic of one Weber IDA 3-barrel

 

Ya my dream is to use a 48 IDA 3c (3 c means triple chamber) on a 20B peripheral port. That would make some serious horse power. With a turbo like a T100 probably well over 7 or 800 horses. what do you guys think?

CJG

 

I'd be happy with a NA 20B!!

 

Old 13Bs had 9.2:1 compression and the 20B has 9.0:1 compression rotors like the '89+ TII engines. That means if you needed to, you could get away with using NA induction on stock rotors for a while. The power potential for the engine will be lower, but I might have to do that while I save up to get a proper induction system. A 20B ain't cheap.

 

Ever since I got my 89 GTUs a few years ago, I've always wanted to make it into the ultimate non-turbo with a streetported, high-compression, fuel injected 20B. This would conservatively put out 300+ hp in a dead-reliable, understressed form, with a crapload of torque <drool> :) With no turbos and the associated plumbing, it would not be that hard or expensive to do. I'd fire the plugs with a distributor and control the fuel with an SDS. A custom TB would need to be made, but that's not a big deal. I had considered the tripple throat Weber, but Rob Golden assures me it wouldn't work -- way, way too small. He has one in the shop, and it's a puny bastard :) My Peripheral Port 13B uses a 51IDA, and even a streetported 13B needs a 45 or 48. Also, carbs have simply been eclipsed by even the most rudimentary FI system. Carbs are cool on 1st gen or earlier rotaries, BMW 2002s, Datsun 1600s and 510s, Triumph TR-4s, old Ferarris, and so forth, but I'm just a sentimental fool :)

The other crazy idea I had for my GTUs is a competition 13G. 3 rotor, peripheral port, dry sump, fuel injected, non-turbo, pure race engine that Mazda sells new for about $30K, complete with ECU and associated sub systems. 450+ hp. Not quite drop in <grin>, but certainly not impossible for any competent race prep shop. Not streetable in the conventional sense, but a fun Saturday night cruiser....

Just gotta hit that lottery jackpot :)

 

a 'street ported' 3 rotor engine can make 400HP, a PP 3 rotor can make around 500-530 HP. also if you are going to carbie a 3 rotor and ditch all the electrics assosciated with efi, how exactly are you going to control the spark? you can buy a 20B distrubutor from i think it's maz-fix in aussie, they are around $1300AUS.

A 3 rotor PP turbo would make 7-800HP at around 5-10psi boost, blow in over 20psi and you should be well into 4 digits

 

Why don't any of the big drage guys go to a 3 rotor pp turbo and blow over 20 psi? I think they should and it would defnintely start to make a name for us in the drag world for sure. Oh ya Blake do you know if Rob at pinneaple uses a "D" shaped pp or is that a secret? I was just wondering. Also do you know how much he charges to boar a 48 over to 51? I live by seattle and am building a pp. Any ways thanks.

CJG

 

They're waiting for you to try it first.

 

Just to expand upon my first question, why is it that all the big rotary drag guys use bridge port engines rather than a pp? A pp can generate as much torque and quite a bit more hp. Is it because they don't know how?

CJG

 

You got a part number for that?

 

what about sammy?....what he desnt run a pp bowing almost 30lbs

hey evil avitar---see the big round jug next to the intake pipe.....next to the radiator....thats the oil. it is a dry-sump motor fyi, they do exist.


i guess no one has done it....right.

 

see above

 

Is that that 3 rotor MX-3?

 

no, its a tube frame 2nd gen....the one in my av.

 

Hehehe, I can call Mazda Motorsports on the phone right now and order a dry sump front cover. What I was asking for was the part number for the complete 13G engine with ECU for $30K.

 

Isn't that the Siguel Racing car?

 

no, its a guy named sammy. i think he is fom lodi NJ.

evil- i have a feeling you think i was being ignorant in that statemet. just for the record, i wasnt. and i think this guy blake used to go under the name pp13bnos....if so...he does know about pp motors. he had a site and a daily driven pp motor, he may know something.

this would be siguel