What would be a better drag/weekend car?
 

Planning on getting a 85 gsl se and not sure what would be better for more potential performance wise. 12a with a side draft carb and making an addition of 2 more rotors to make a 4 rotor. Or to have FI 13b thats turbocharged. I always wanted a turbocharged car but ik 12a can be beasts without being turbocharged. If I could get some opinions I'd appreciate it alot. Plus I'm pretty new to rotorys.

Thanks

Is this a serious question?

It is a major undertaking to build a 4 rotor engine. The kits available start at $4000 for the eccentric, modified center irons and other bits. Then you'll need to source 4 good 12A housings (not that easy), 4 rotors. Then machine them for peripheral ports, assemble it all, fabricate manifolds, etc. If you have a good local machine shop they can make your eccentric shaft and modify the irons at significant savings, but it still isn't exactly trivial.

Any 12A turbo will need to be custom. The factory 12A turbo parts are almost impossible to find.

So if you want a turbo rotary, the easiest thing would be to swap in a 13B-T, 13B-RE, or 13B-REW. All this is well documented and there is only a little fabrication necessary.

It was a serious question, bc I want something to haul dick when I get on the gas. Now I knew it would take time to do the 4 rotor deal and you did remind me how much of a pain it would be lol but the cost doesnt concern me bc im planning on keepin it the rest of my life. I wasnt gonna turbo the 12a bc idk just doesnt seem like something to waste my time with. I can find 12a housings no prob theres plenty of em where I am. Im just so stuck btwn gettin a fc or the fb and making it a 4 rotor which seems to me like something that will be ridiculously fast. But like I said idk alot about these things i just started gettin interested in them this past year and just need help.

Cool factor: 4 rotor

Practicality factor: 13b turbo of some sort.

OK...but you will have $40,000 into a running 4 rotor engine if you don't know a lot about these things (is that what "idk" means?) because you'll be paying someone else to do the work. Then it needs to be installed in the car with appropriate support stuff, and tuned. Figure another $15,000 - $20,000 there. And a 4 rotor 13B (or 12A) will make stupid power. Mazda was pulling over 1000 HP out of their NA R26B as used in LeMans. There are YouTube videos of a 4 rotor based on 13B parts with a smallish turbo (for a 4 rotor) making over 1600HP on fairly low boost. These power levels are obnoxious on the street and the only hope of getting them to the ground would be all wheel drive or a fat set of drag meats on the rear. Even then it would be a tire fire in every gear.

Something to keep in mind is that getting 400 wheel HP out of a 13B is pretty standard these days. And a 400HP RX-7 is stupid fast. That kind of power to weight ratio puts you in league with $150,000+ vehicles. A 400HP RX-7 with a good set of tires and a skilled driver will run mid 10s in the 1/4 mile. It will try to kill you every time you put the fun pedal down, go sideways at 150 MPH and flat out terrify the driver and passenger on a regular basis. My FC on low boost (the ~420HP setting) has caused a passenger to lose bladder control. The high boost (500HP) setting is reality distorting.

I'm sort of saying that before jumping in with both feet where angles fear to tread (and believe me, I've done that), maybe it's a good idea to start with a simple project instead.

I seriously looked into building a 4-rotor for my FB at one point. In the end, I simply could not justify the cost. If I'd built it NA, I could get the same power far cheaper with a turbo 13B without completely screwing up the weight distribution (IIRC, a 12A-based 4-rotor shortblock weighs about 128 lbs. more than a 12A shortblock and is very long). If I'd built it turbo, I'd have had to put together a hell of a drivetrain to handle the power, which I wouldn't be able to make use of on the street anyway.

My conclusion: 4-rotors are neat, but not very practical. A 20B build might be fun someday, though.

The FC race car (not drag car) I have has a rebuilt 13B Turbo (stock turbo on low boost). The engine has been run in the car for over 6 years now and has been extremely reliable aside from often getting heat soaked (no FMIC yet). As long as you're not trying to break world records with power, I'd go with a 13B.

So how could it get any simpler than to just add a couple of rotors? Geez AC, get with it. :)

To the OP...I'm joking of course, but it makes a point. You might want to do some searching on 4 rotors. Out of all the world's rotary engines, there's maybe a few hundred four-rotor versions, including those belonging the MAZDA. There's reasons for that.

Of course, I forgot! Just like I can add a few cylinders to turn my V6 into a V8. Duh, I'm such an idiot. ;)

Whats funny is that multiple times, I've had someone at a car show come up to me and say "You know, you can just keep adding rotors to these things and make more power". A total facepalm moment.

Build it with a small block Chevy it will be fast and probably be more reliable

What I like to do is weld two e-shafts together and kinda sandwich the engines together..

It's just too bad that 90% of SBC conversions I've seen are old iron block engines salvaged from some junkyard van, complete with slushbox, that weigh 700 LBs and make 180 flywheel HP. Instead of nice new LS series (like the awesome e-rod engine) and 5 or 6 speeds.

Now, why? Because to do it properly is as expensive as building a 13B properly. Making good reliable horsepower always costs money regardless of the engine.

If you did 3, you could have a 6 rotor!

Meh, why bother? All it takes is a MIG and hand-file. Do four and have an eight-rotor or just go home.

Welding? You guys are making it way more complicated than it needs to be. Rubber bands and duct tape do the trick just fine. I've got a few 11-rotors I've built that way, all of them making over 9000 WHP with electric superchargers.

I'd love to see you go the 4 rotor way to be honest but damnnnn that's alot of work. Good luck!

JB weld and a prayer!

A better drag car would be a 1990 5.0 notchback ford mustang!

With just a few mods and some slicks, you'd be doing 11's all day :)

Hell no don't do this, like I tell the guys in the Nissan community who do the same thing your destroying the import scene.Basically your saying the Japanese can't make a good motor or even good cars so I have to go american. If you want a v8 powered american motor why don't you just buy a mustang,camaro,buick or vet. If your going v6 v8 etc at least keep it Japanese

I have a first gen rx7 with a 383 in it I have not even 3000 dollars in my motor made 420 horse car went 11.40 123mph car weights 2700 pounds with me in it and I don't have to rebuild my motor ever 100k changing a my heads to a set of afr and intake to weiand team g going to pick up about 80hp so for 5000 I have a 500hp motor all motor no turbo no adders no nothing best part Is its got a 5speed auto in it so if you Japer's want to go on the highway that's fine by me

Yea they are pigs nowhere near 700. through alum heads on and intake and there's 100 pounds off they weight just over 300 pounds assembled . Not a rotory hater just a light car to an 8 in and make good numbers out of and a sleeper on the streets.

That sucks, lol. Ya, you could just wet shot 250 to a 5.0 mustang and grab some slicks and you'd be doing 10's all day.

A 383? Thats a lot of work.

https://edge.ebaumsworld.com/mediaFi...1/81751531.jpg

Are you ever at St. Thomas dragway? I'd like to see you car and race. :D

Ya it does suck should have bought a mustang and done what you said maybe get a couple of pass then need another motor. Plus 100 dollars a bottle to fill and at the end of the day it's still a ford mustang. I have a nitrous system for my car but it's nice to do it all motor getting a car into the ten is a little more difficult then you think but I guess you should tell me how to do it seeing as how you have probably done it right

No Cayuga buddy nice bra it's that for your b cups

Damn, I'm almost never at Cayuga since Sparta is only a 20 minute drive from my place.