Carburetor to fuel injection system swap ?'s
03-22-07, 10:57 PM
#1
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Carburetor to fuel injection system swap ?'s
I have a 85 12a and I want to put a fuel injection system in. Is it hard?
What year would I have to get the system out of if I did not want to buy a brand new one?
What year would I have to get the system out of if I did not want to buy a brand new one?
Last edited by Rx-7Doctor; 03-24-07 at 01:16 AM.
03-23-07, 06:34 AM
#4
Welcome to the forum and the Darkside. After reading the sum total of your 3 posts so far, it's time to start with the basics. 1st being, read the FAQs, then peruse the archives, then become good friends with the search function.
Reading through the FAQs will give you an idea on how to ask a proper question, it will not, however, improve your syntax or spelling so your question can be more easily understood.
Converting the carbed 12A to FI will most likely cost you more than you paid for the car, so my question is, 'What are your goals, what is your budget, what is your mechanical experience/ability and what do you hope to gain by going FI?'
Answer these questions, then perhaps we can answer your first question or at least point you in the right direction. To answer some of the others ahead of time and part of what you asked in other posts, yes, it's possible to FI the 12A, financially for the gains, it's not very practical. Can one turbo a 12A, yes, will it blow up, yes, no and maybe. Going to the dealer and asking if you can turbo your 12A is the last/worst place to ask that question and they would most likely blow up the engine before you even have a chance to drive the car.
First decide what you want from the car, performance wise, and your intended use. If all you want is a turbo and FI, then buy a car that is already turbo and FI. If you are willing to build one, can afford it and have the skills, tools, space, know how, etc. to do it, then start reading.
I'm not trying to be harsh with you, just reining in the F&F/Initial D/NFS dreams with a little reality check, before you get lost and/or caught up in the mystical hype that sometimes surrounds the rotary hummmmm.
In my sig line is a link to the online FSMs, carb manual, competition prep manual, etc.. Read and download whatever you need, then read some more. Enjoy.
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Reading through the FAQs will give you an idea on how to ask a proper question, it will not, however, improve your syntax or spelling so your question can be more easily understood.
Converting the carbed 12A to FI will most likely cost you more than you paid for the car, so my question is, 'What are your goals, what is your budget, what is your mechanical experience/ability and what do you hope to gain by going FI?'
Answer these questions, then perhaps we can answer your first question or at least point you in the right direction. To answer some of the others ahead of time and part of what you asked in other posts, yes, it's possible to FI the 12A, financially for the gains, it's not very practical. Can one turbo a 12A, yes, will it blow up, yes, no and maybe. Going to the dealer and asking if you can turbo your 12A is the last/worst place to ask that question and they would most likely blow up the engine before you even have a chance to drive the car.
First decide what you want from the car, performance wise, and your intended use. If all you want is a turbo and FI, then buy a car that is already turbo and FI. If you are willing to build one, can afford it and have the skills, tools, space, know how, etc. to do it, then start reading.
I'm not trying to be harsh with you, just reining in the F&F/Initial D/NFS dreams with a little reality check, before you get lost and/or caught up in the mystical hype that sometimes surrounds the rotary hummmmm.
In my sig line is a link to the online FSMs, carb manual, competition prep manual, etc.. Read and download whatever you need, then read some more. Enjoy.
.
.
.
.
.
.
03-23-07, 09:40 AM
#5
Well, now that you've been flamed, I'm going to start by welcoming you to the forum.
Just "adding FI" to a carbed first gen is not easy or cheap. You'd be better off buying an 84-85 GSL-SE which had an FI 13b straight from the factory, and start your mods there (aftermaket computer, etc..).
You could swap a GSL-SE 13b into your current car, it's definitely been done before, but in my opinion if you're going to do an engine swap, you might as well go all the way and grab the fuel-injected turbo 13b from a second gen Turbo II car and swap that in instead.
As trochoid said, your budget and your goals will ultimately determine what route you take. The most important thing to remember is this:
Fast, Reliable, Cheap - Choose any two.
Again, welcome to the forum.
Jon
Just "adding FI" to a carbed first gen is not easy or cheap. You'd be better off buying an 84-85 GSL-SE which had an FI 13b straight from the factory, and start your mods there (aftermaket computer, etc..).
You could swap a GSL-SE 13b into your current car, it's definitely been done before, but in my opinion if you're going to do an engine swap, you might as well go all the way and grab the fuel-injected turbo 13b from a second gen Turbo II car and swap that in instead.
As trochoid said, your budget and your goals will ultimately determine what route you take. The most important thing to remember is this:
Fast, Reliable, Cheap - Choose any two.
Again, welcome to the forum.
Jon
03-23-07, 09:51 AM
#6
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Originally Posted by trochoid
1st being, read the FAQs, then peruse the archives, then become good friends with the search function.
Originally Posted by trochoid
Can one turbo a 12A, yes, will it blow up, yes, no and maybe.
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03-23-07, 01:30 PM
#8
Duct-tape fixes all
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You can get the hardware to make a FI system cheap. You could use the throttle boddy and injectors off an old chevy. However, u need still need a computer. For That your cheapest bet is megasquirt, but that is still rather expensive once everything is running. It's the software you payfor.
03-23-07, 08:42 PM
#9
Yeah, shutup kid.
If you are good with mechanics and fabricating your own stuff it wouldn't cost too much. The stock carburator has a throttle body, just unbolt the carb from it and use that throttle body. Weld injector fittings onto the stock intake and make your own fuel rail. Since the throttle body doesn't have an idle air control valve you can buy an external one you can mount anywhere, and just run a hose to the intake manifold anywhere under the throttle body. A GSL-SE fuel pump should work fine up to around 200rwhp. If you use a megasquirt ecu the price should be under $500 total.
03-23-07, 09:36 PM
#10
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There is ways to it fairly cheaply and use Mazda parts. Adaptor plates can be made to fit 13B manifolds on to 12A motor, the stock injectors would be fine for your application. As others have possibly mentioned already you can use a fuel only computer and still use the Electronic dizzy for ignition. Then all you need is an efi pump,surge tank and fuel pressure reg
03-24-07, 12:42 AM
#11
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For 500$ you could probably do a stock s4 swap over. That would give you probably around 150-160hp. But you will probably have to drop the coin on a new exhaust. So if you are going to replace your exhaust, upgrade to a second gen 13b. More hp for less $$$. If you don't want to spend the coin on a new exhaust but want a bit more hp, and fuel economy, and like to play under the hood FI is a good way to go.
01-07-08, 12:04 PM
#15
My 12A... IS SO CUTE!
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I know where you're coming from... My dad just gave me our old 83 rx7. I'm a girl, and though I've worked on this car extensively, I've never touched the fuel system. Right now I'm having problems with it (spec. fuel pump), and considering switching to FI (it's got the factory carb on it now, I pulled the emissions off the car when I was about 11) but don't know anything about it. All this talk about surge frambagulators and equip. makes me dizzy 'cuz i don't understand it. I wanna know... is there something out there that I can just bolt on, calibrate and go? I'm sure that's what you were thinking when you posted this...
THX and sorry for being a n00b and posting randomly...
THX and sorry for being a n00b and posting randomly...
01-07-08, 03:41 PM
#16
Intersting 1st post. The only thing that even comes close to being bolt on and go would be the 84-85 Se engine, ecu, wiring and fuel system. Frankly, for the work and few extra hp, definitely worth it. Almost all FI conversion include an engine change to a 2nd or 3rd gen power plant, running a stock or standalone ECU.
If your 12A is in good condition engine wise, the standard exhaust and carb mods would probably suit you better at this time. Most who try to do an FI conversion on a carbed system end up reinventing the wheel on thier own. I doubt that there are 2 systems alike worldwide.
If your 12A is in good condition engine wise, the standard exhaust and carb mods would probably suit you better at this time. Most who try to do an FI conversion on a carbed system end up reinventing the wheel on thier own. I doubt that there are 2 systems alike worldwide.
01-07-08, 10:13 PM
#19
FB+FC=F-ME
Unfortunately,fuel injecting the 12A with factory or junkyard parts is about the toughest task you can undertake.I would have gone that route long ago had it been an option and I hadent decided on the EFI 13BT I used in the end.
There just arent any stock fuel injecton systems that can be made to work easily(or at all) on a rotary engine.Our engine size belies its extreme hunger for air and fuel.This makes rotary EFI systems somewhat unique in their calibration and physical setup (only having two "cylinders", but needing very large quantities of air and fuel compared to similar sized piston engines)
The only EFI 12A engine was the Japanese 12AT,and its rare if not impossible to find one in the states with all its EFI parts intact.Plus its a turbo engine,with different needs than an N/A engine.
The non turbo 13B engines that are EFI, are indeed similar in size and shape to the 12A,and those engines are pretty common in wrecking yards.But the factory computors are setup to run the bigger 13B engine and are not re-programmable being they are metered air style EFI.It just wouldnt run right,sure it might start but theres no way the mixture would be correct in all situations and conditions...... and thats pretty much the whole point of going to EFI.
The only feasible way to convert a 12A to EFI is to.......
1.Physically adapt any 84-92 13B injection intake manifold and its sensors to the 12A,which isnt too hard a task....then install and program a standalone ECU to operate the 12A engine in a "speed density" type setup.Speed density is very reliable and simple,its what Hondas and many other 90's cars use,although the rotaries never got it,save for the 3rd gen.
2.Go for the big bucks and use an aftermarket ITB type injection system with a standalone ECU.The dual throttlebody type intakes are simple and sexy,although they probably will cost you a bit of torque and tractability over the long,convoluted Mazda intake manifolds.
There just arent any stock fuel injecton systems that can be made to work easily(or at all) on a rotary engine.Our engine size belies its extreme hunger for air and fuel.This makes rotary EFI systems somewhat unique in their calibration and physical setup (only having two "cylinders", but needing very large quantities of air and fuel compared to similar sized piston engines)
The only EFI 12A engine was the Japanese 12AT,and its rare if not impossible to find one in the states with all its EFI parts intact.Plus its a turbo engine,with different needs than an N/A engine.
The non turbo 13B engines that are EFI, are indeed similar in size and shape to the 12A,and those engines are pretty common in wrecking yards.But the factory computors are setup to run the bigger 13B engine and are not re-programmable being they are metered air style EFI.It just wouldnt run right,sure it might start but theres no way the mixture would be correct in all situations and conditions...... and thats pretty much the whole point of going to EFI.
The only feasible way to convert a 12A to EFI is to.......
1.Physically adapt any 84-92 13B injection intake manifold and its sensors to the 12A,which isnt too hard a task....then install and program a standalone ECU to operate the 12A engine in a "speed density" type setup.Speed density is very reliable and simple,its what Hondas and many other 90's cars use,although the rotaries never got it,save for the 3rd gen.
2.Go for the big bucks and use an aftermarket ITB type injection system with a standalone ECU.The dual throttlebody type intakes are simple and sexy,although they probably will cost you a bit of torque and tractability over the long,convoluted Mazda intake manifolds.
01-08-08, 04:14 PM
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http://www.auto-nomics.com/cgi-bin/s...q=all_products here is one set up that u can run will work fine with your car and tunning it , its not that difficult all u need its a racing beat intake to work with it. u can either run their ecu set up or run microtech fuel only . which is chepeast way u can go but this still will run u around the 1.5k mark . http://i39.photobucket.com/albums/e1...arparts047.jpg or u can run my set up here. but that will bring u a bit higher closer to the 3k mark. but w/e u chose gl with it i know it can be done its a matter of who will do the work for u and how much u have for a budget.
01-08-08, 09:46 PM
#21
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http://www.auto-nomics.com/cgi-bin/s...q=all_products here is one set up that u can run will work fine with your car and tunning it , its not that difficult all u need its a racing beat intake to work with it. u can either run their ecu set up or run microtech fuel only . which is chepeast way u can go but this still will run u around the 1.5k mark . http://i39.photobucket.com/albums/e1...arparts047.jpg or u can run my set up here. but that will bring u a bit higher closer to the 3k mark. but w/e u chose gl with it i know it can be done its a matter of who will do the work for u and how much u have for a budget.
01-09-08, 12:25 AM
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I am using a weber/dellorto DCOE wraparound 12a manifold. I have the Injector bungs for the primaries installed.
I am just finalizing the TB's size and running a Mega squirt.
I paid $233.17 for the FB, bad motor. Bought another SA with a good motor for 110 dollars.
Swapped motors. Sold Beater SA for 100.
Running FB = $243.17
EFI Setup thus far.
DCOE Manifold = $80
MegaSquirt = $210
Fuel pump = $65
Injectors = $125
Regulator= $309 (super nice BEGI for the turbo setup on the floor)
TB's Estimated = $450
Total = $1239
Trochoid is right... EFI exceeded the cost of my car 5 times over!
Okay...
I am just finalizing the TB's size and running a Mega squirt.
I paid $233.17 for the FB, bad motor. Bought another SA with a good motor for 110 dollars.
Swapped motors. Sold Beater SA for 100.
Running FB = $243.17
EFI Setup thus far.
DCOE Manifold = $80
MegaSquirt = $210
Fuel pump = $65
Injectors = $125
Regulator= $309 (super nice BEGI for the turbo setup on the floor)
TB's Estimated = $450
Total = $1239
Trochoid is right... EFI exceeded the cost of my car 5 times over!
Okay...
03-25-08, 01:07 PM
#25
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well i did a swap i just stuck the 13b six port out of a GSL-SE ended up blowing up that engine too much carbon in it. then i put the S4 six port from a second gen in it. all i wanted to do was make my GS in to a GSL-SE so now I'm going to modify the heck out of it due to blowing up that SE engine. you did not ask a stupid question but we here these questions like all day everyday and these guys like giving less help per time people ask them. sometime before you ask these questions you need the use the search bar at the top of all the pages more to the right or even look through the archives we cover this question way too much. thats why you go t the answers you do.
well i did a swap i just stuck the 13b six port out of a GSL-SE ended up blowing up that engine too much carbon in it. then i put the S4 six port from a second gen in it. all i wanted to do was make my GS in to a GSL-SE so now I'm going to modify the heck out of it due to blowing up that SE engine. you did not ask a stupid question but we here these questions like all day everyday and these guys like giving less help per time people ask them. sometime before you ask these questions you need the use the search bar at the top of all the pages more to the right or even look through the archives we cover this question way too much. thats why you go t the answers you do.