It's an '85 GS, 100% minus the wheels (those have been changed to 15") and minus the engine (or however much of it I can't salage)
I have little money, I'm lookin at about 1200 to spend, but I am a mechanic, I can work on anything I can get my hands on.
The thing is, every engine has it's own personality and quirks, and I have no experience with a wankel. So I need YOUR help! You guys know the 12a and all its kinks.
So I'll tell you what I got, and what I want, you tell me what to do in a general way, or a specific way if you type fast...

OK, I got an 85 gs N/A 5sp, standard holley carb, complete with a hole in the side of the motor. I dont know where the hole is - but the story goes; my buddy ran it with a blown apex seal untill it got so hot a hunk flew off. That simple. He owned it six mos and bought it from the origonal owner who took great care of it. Now I own it for 300 bucks because he's a dumba**! He's really great with a Ford though...

I want basically 350 HP, or as much horsepower out of the car as possible without stressing any of the stock drivetrain or suspension too much. I "THINK" that I would like a single turbo, and to keep the carb, or at least some sort of carb. I know I want to keep a 12a in it, but I dont know if I should rebuild the one I have or get another one to rebuild.

I'll take pics, but it will be a minute, I don't have a digital camera yet.

Please keep in mind, I have 1200 to spend, but I will do all of the work that dosent require special equipment. Jacks and hoists aren't special, neither are basic tools. Machine shop work is special, but I hear you can get paper templates for a street port pattern... I could maybe do that much machining myself...

Well, what do you think I should do? ANY advice is really appreciated. And hey look at it this way, at least I am trying to keep a classic real and alive. No rusting in somebodys yard, and no hotrod V8 crap swap either.

 

for 1200, you can buy an 85 that runs..
just look around.

 

Yea. Or... Find a beat up or totaled TII with a good motor and all of the components still there. Go TII!

Edit: Okay... a 12aT will cost way more than $1200 for everything you'd need sooo yea, get a running 12a for like $200.(You want to be able to salvage as much as possible in the rebuild) Then get a street port/larger port template. Buy a gasket kit. Rebuild the motor with a street port or even larger port. Then find a Mikuni or Delorto or Holley carb. Throw on an RB header and full exhaust. Boom with the right work you can hit 300-350.

The larger the port you do the more risk you run of damaging the motor or decreasing motor life but on a $200 motor... Eh. The benefit of the larger port is MORE AIR FUEL MIXTURE!@ MORE POWER. VROOM VROOM errr should I say BUZZZ BUZZZ.

 

Thanks guys, but I dont think I want stock turbos, like I said before, I want 350 HP, thats not under the hood of any wrecked cars, unless the owner died in it maybe. I was thinking about rebuilding the 12a I have and putting a 3-500 dollar used turbo on it.
Correct my prices, or anything else I've said if I'm wrong here.

I figure:
500 for a turbo
300 more for the parts requierd to operate it
200 for a rebuild
200 for **** I haven't thought of yet (or is it like 800? )

That's 1200, so what am I missing here?

 

84RX_Se7en I think you should recheck your numbers the pp guys with 12a's are only making that N/A. If I remember correctly a streetport can only reach just under 200hp. Although just under 200hp and a decent turbo could probably put you to your goal hp.

 

$200 for rebuild? Its more like $400-$1200+, depending on whats damaged.

 

OK, this guy just told me it would cost up to 1200 to rebuild an engine that I can replace with a jspec for 550, that's a current price I just got from a link in the faq, so I'm sure I'm right about that....
I can't imagine new gaskets and bearings are gonna cost much over 200, and even if I need a new housing they can't be more than 100 bucks. What gives?

 

Notice I said a larger port. I know a street port will only give you maybe 200-250.


Now I don't know about the turbo setup costing less than $1000 unless it's way used or it's a stock TII setup. Either way you're talking ECU and wiring harness as well as fuel system. Also a TII transmission and so on.

 

Standard holley carb? Someone put one in?

I is confused

 

Aftermarket.

 

If you can find me new housings for $100, I'll but 6 today! I swear!

 

Keep shopping and get a plan. I think it will be a bit more than $1200 budget can handle...

 

350 hp on $1200, ain't gonna happen. A decent turbo and external wastegate is more than that. I'd be more than happy to type out a reality check on prices, but I have a headache this morning.

Welcome to the Darkside and good luck, you'll need it.

 

This stuff doesn't grow on trees. Very few companies make aftermarket housings, gaskets, seals, rotors, etc. They are expensive to replace and you can buy used but even then it's hard to find what you want right then and there for a decent price. You can sometimes get things at a decently cheap price from someone but chances are you'll have to refinish or rebuild it. Which costs money.
Housings and rotors are the most expensive of all. Especially to buy refurbished/refinished or have redone. To fabricate is rediculously expensive. Apex seals are pretty expensive but not bad. Gasket sets with EVERYTHING to do it properly run at around $1k to $1.5k depending on what you want.
Another point. There were certain makes of each motor that just plain had better quality housings or rotors or a better this or that part. Those are sought after and desired, especially in a performance application, so those will cost your arm and maybe a leg.
Now new turbos to fit these with the proper manifolds or modified manifolds will be increasingly expensive over your $1200 range. More like $2k to $3k. Then there is the ECU, fuel system, different ignition mods, and so on. To rebuild and put a 12a at 300-350HP with a turbo is gonna cost.

Just rebuilding a 12a with a PPORT will still cost your entire $1200 for the rebuild and then some for the port and a new carb and possible fuel mods to own up to all that new space in the motor.

While general maintenance on a stock car isn't the MOST expensive compared to some to mod and upgrade performance wise they can be very expensive.

 

OK dude, look up 12a housing on ebay. there are 4 for 100 or less, the cheapest is 65 bucks. They are all tagged "buy it now" so the price isnt gonna change. Get to buying them up then, buddy.

 

Yea, probably all scored and cut up from blown motors too.

 

Well, man, it's like this... I've had two RX7's so far. Both first gen GS 5 sp. I had the same exact tiny little holley 4 bbl carb on both cars, so I assumed they were a stock carb. What are the odds of getting two exact aftermarket carbs on different cars ten years apart?
But you say the RX7 never came with a holley 4 bbl carb? OK, I believe you, so what do I have and is it worth a crap? All the descripotion I can give is it looks like about a 200-350 cfm, and it's a holley 4 bbl. Man, it's little anyway...

 

post a pic of it.

 

well, since you dont wana look it up yourself, heres the ad description for one of the four housings....

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This is the FRONT ROTOR HOUSING to a 1981-1985 MAZDA ROTARY 12a Engine. NOT 13b. Look elsewhere in my eStore for 13b engines and parts.

I sell these 12a rotor housings in three different classes; Class A = $120 Housing is in used, but excellent condition, Only 1 left. Class B = $100 Housing has minor wear or edge chipping, within Mazda spec for rebuild, and Class C = $80 Housing is marginal, the wear is beyond spec, but not severe--for use in a "Budget" rebuild. I also have a number of damaged rotor housings that can be used for clock kits, or as bookends...

CONTACT ME about what class of rotor housing you would like.

As always, S&H are at buyer's expense.
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There, man, I'm about done with this aspect of this conversation. You are just wrong, accept it and either offer some advice or go away.

 

I plan to, but I havent got a camera, I'l have to borrow or buy one... It will be a few days at least before I can post pics. Sorry 'bout the difficulty.
It's definetly got holley stamped on the top, and it's definetly like the one I had in my other RX7 though.

 

Welcome,

You definately need to get your numbers cleared up and face reality.
350HP in a stock 100HP car, is not only ridiculously fast,its very expensive.Almost nothing on the car is capable of handling that much power safely or for extended periods. Asking a 1st gen to make and handle 350HP is like asking a Mustang to do 800HP.....sure it has, and can be done,but not on a shoestring budget.
I'm making about 300HP now with my 10 year project,and Ive got about 10 times your expected budget spent on my drivetrain alone.Nothing about making a 300HP 1st gen is gonna be cheap,unless you do it unsafely or have some serious hookups.Im a mechanic as well,and I did nearly all my own work.Just the basic parts and nickle-n-dime stuff for the TII swap ran about 1200 bucks,and that was just for transplanting and making run,a bone-stock 180HP TII engine.I spent easily twice that in mods......and then another $4500 for a pro built 13BT block when my first junkyard engine gave up the ghost after 6 months.
Just remember,the most expensive rotary is the one thats built twice or three times because you cheaped out the first time.I learned my lesson early and quickly.Turbo rotaries are VERY unforgiving when mistreated or deprived of the good/right stuff.If you decide to pursue a TII swap,then all the info you need is here,and we'll be glad to help with any specific questions you have along the way.

 

Why take advice from you? I've been nonstop shopping for parts for the past year as both of my RX7's are project cars. Both need work and both need built motors before I do what I want to with them. Right now my SE is just going for a restore to DD condition for the Spring/Summer to have fun. That alone is going to cost me to refresh with decent well handled hardware.
That's shade tree mechanic chop shop **** coming off blown motors. Most people that post stuff on ebay for these half the time don't have a clue. They chopped up a 7 cause it didn't run anymore and figure they'll make some money parting it out. Also those "Class B" and "Class C" housings would not handle 350hp. I doubt this persons "Class A" are up to proper spec to handle it.

Now think... if one of these costs a fortune to get totally up to par mechanically as if it rolled off the showroom floor then think about going THREE times beyond that mechanically and completely outstepping the bounds of all other hardware on the car from the fuel system to the drive train.

Best bet is to save more, buy a front clip from a TII FC or S5 FD for about $3k. Then piece together a suspension to maintain. Check Granny Speed Shop for the Ford rear kits. Then get a GSLSE front cover and oil pan. Then modify the OMP to fit the SE front cover. Bingo Bango Bongo finish up the fuel system with the braided lines and pump and go to town.

 

Oh and I'll be the one to say it... Tiny little 4 barrel carb? That's a Nikki carb.

 

OK, since you feel you know quite a bit already, let's argue a bit. If you're going to build a 400+ hp engine, none of the housings listed will safely last for your needs. You pick up a marginal housing, toss an apex seal, you will be replacing all 3 apex seals, the housing and the rotor. Where is the value in that? Add in the cost of a fresh gasket kit at around 200+ and you have flushed nearly 1k down the toilet, not to mention the probable damage to the turbo. They most definitely do not like ingesting apex seals.

A short run down of needed parts for a 400 hp TII engine build as a reality check:

TII rebuild kit: 1100+

Internal engine mods for high, 8k+ rpms. List includes, but is not limited to:
Hardened stationary gears
3 window bearings
rotor clearanceing and balanceing
upgraded oil pump and oil pressure regulator
e-shaft oil mods
oil pump chain
1200+

Turbo
To get 400 hp start with a GT 35 minumum. Keep in mind that turbos for rotarys are vastly different than one for a piston 2500+

Exhaust mani and external wastegate. Wastegate is one thing you do not cheap out on, overboost it or have a boost creep spike and it's rebuild time 5-800

Fuel system upgrade:
Entire system from the tank forward needs upgraded, including lines, injectors, pump, fpr, etc. ReTeds parallel fuel system upgrades takes 200 in fittings alone. Add to that the pump, surge tank, yada yada, 6-800+

Full custom 3" exhaust 4-800 including pre-silencer and muffler

Ecu. Anything over 250-275 hp will need either add ons, or, in your case, a full blown stand alone. 600-3500, depending on choice of units. There are no OBDIIs for pre-RX8 rotarys.

Tranny/clutch. TII tranny is a must, 250 for the modded driveshaft, 400+ for a decent clutch, pp and flywheel, Full out twin disc OS Geiken can run 2500

Rearend. Drag launching the car on a regular basis, upgrade to a Ford 8.8. Granny's makes a bolt in kit for 1700+ Does not include hardened gear sets or axles

Add tires and wheels of your choice and price range for traction.

Fmoc and piping 300- 2k, depending on diy or modding another kit to fit.

Roll cage to meet NHRA rules, parachute if you break 150 mph

Ignition upgrades, some of which are not cheap in the least.

E... there was something for this line but the phone rang and I've forgotten what went here.

Brake and suspension upgrades/ If you go faster, you need to be able to stop better, goes without saying.

As you can see, dollars add up quickly and this is by far not a comprehensive list. Please don't take me wrong, I'm not trying to shoot you or your idea down. I have a Honda friend that literally picked up used parts off of the dirt floor in his shed, built a a turbo engine and ran 9.3 in the 1/8th mile his 1st time out. spinning his tires all the way through 3rd gear to the finish line.

Unfortunately, you can't build a rotary in the same manner and expect similiar results. A rotary engine is a totally different beast and does NOT take well to detonation nor overheating. Fuel, timing, boost, egts and exhaust flow are critical factors that often work in a very narrow range if one wants hp, reliability and longevity.

To answer your question about boosting an SE engine, I doubt that there is a rotary made that someone hasn't used forced induction on, (except maybe the old 10As with 6 mm apex seals). When done right, they are a hoot. However, the SE, or 6-port rotarys in general are not a good choice for high hp boost. The 4-port engines are a much better candidate.

So, a word to the wise, from the wise. We are more than happy, willing and able to offer help/advice, take it or not, but, and there's always a but, don't cop an attitude or come off like you know more than we do since you just joined. I know very little about building Hondas, so I respect your knowledge of them and what you have accomplished with your's. Since you came to us on a rotary forum asking for input, please show the same respect and courtesy towards us in return.

I will also suggest that you spend some time in the 2nd gen forum since the best engine choice for your goals would be an S4 or S5. There you will find a number of setups that more than exceed your goals and the correct way to build it. Be forewarned though, we are much friendlier here. Having an attitude in the 2nd gen forum can be the kiss of death, lol.

Good luck with your project.

 

Wow, OK, first off I'll admit to being a little obnoxious there, apologies to 84RX se7en. But I did find a housing for 65 bucks! Oh yeah, and I wasn't trying to give you advice, I was asking for yours. I still am too, if you can help, thanks.

second, trochoid (who argues very verbosely, but nevertheless seems to really know how to build a sharp dragster) should have read my first post before giving me all that accurate but useless info. I'll explain...

I want as much HP out of a stock (except for street ports) 12a as I can get. Thats what I said. As much as I can get without tearing up the tranny or suspension. I plan on getting a newer gen rear for the various benefits they are supposed to have, but that's later.
I was and am still considering how best to go about a single turbo. All the advice I've gotten so far is to get a t3-t4 hybrid, and I think that would probably be overkill, though it might go really fast for like ten minutes...

So, you have shown me that I can't rebuild an engine for what I can buy another one for. That's a certainty, for I know where theres a running 12a for 200, and I can get it for less if I cajole enough. The question is, can I take it apart and port the heads without replacing the parts that are usually in a rebuild? If I cannot, then I will not rebuild it, or port it.

These are the facts I am working with:
I have a stock 12 a with a hole in the case, it was heated up until I bet it was glowing, and so I don't trust it to handle any real work. I don't know if warping is a problem but if it is it's warped I bet.
I can (and probably will) get a running stock 12a shortblock to replace my damaged one.
I want to street-port the stock motor, but if I cannot afford to put the motor back together then I won't take it apart and port it.
I want to put a turbo on the 12a and retain a carbeurator.
I want as much HP as I can get without tearing up the tranny or suspension.

Any advice along those lines would be great.