Im searching for the necessary info needed for turning my 12a from carb'd to EFI...and i dont want to go IDA EFI if at all possible.....ive emailed robert at rotaryshack but i figured i would post up a thread as well i figure hell at his reply in this thread....im noticing that a lot more turbo FB's are coming outta the wood-work and i think that this conversion is a much needed sticky

another question i have is how difficult would it be to use a 13b intake manifold, injectors, throttle body and modify it to fit on the 12a?...is this even possible?.....any advice is greatly appreciated...thanks...parker

 

well i'm doing this too, do you have an efi centerplate?

 

here are 2 style throtle bodies for efi down draft and side draft both you can buy at rotary shack i remember talking to you about the hole set up you also need a stand alone ecu wich he can also supply tell him i send you my name is Alex he will know.

 

Maybe you should check out this guy in the MegaSquirt section:

https://www.rx7club.com/forum/showthread.php?t=493266

 

cheap way:

GM TBI from junkyard ~$10-50 with wiring and all sensors (put them in pocket)

TBI to Holly adapter from jegs ~$50

Holley manifold from Racing Beat ~$125-200

Megasquirt ECU running standalone ~$200

you'll need to tap your manifold for a vacuum source for the MAP sensor, and maybe ignition advance if you want to.

 

Whats that sidefraft TB going for?

Thanks, Ed

 

That IDA style Throttle body with the rails and injectors is pretty steep. IIRC it's around $450 and you still need the manifold.

 

i got a 4injector 50mm TWM IDA for 300 and a mani for 150....both new

 

The side draft style i think is 300 here is the website you can call them they will price it out for you. http://www.twminduction.com/throtleb...lebody-FR.html check it out.

 

bean 8044, where did you get your FI ida and intake from? Got any pics?

Thanks, Ed

 

Yeah, seriously, I wanna know too cause that is really cheap. Does it include rails and everything?
That's my thread in the FI section. Runs really good right now, though not great mileage because I haven't tuned it for that yet. Wasn't on the cheap side. Expect to spend 1k or so for a good setup. Actually, I got a FC the other day and am selling it off.

What do you have against IDA style anyway?

I would definitely not recommend rebuilding a good 12a with a 13b centerplate JUST to get those injector holes. The way to go is aftermarket intake. Either holley style or IDA. You will not be disappointed I promise. Anyway, injecting from an even spot on the intake gets a better/more even air fuel mixture than the stock primary/secondary setup, I believe.

 

alright right now my only issue is getting all the parts needed....if i do go with the IDA setup what else needs purchased? also money isnt a thing for this b/c ive been saving for a while and i have roughly $4000 for this project.....if i run the megasquirt will i have trouble's tuning it with the boost of my turbo? or should i just get a microtech lt-10 for tuning?

right now i have a holley racingbeat manifold never used is there a TB that i can purchase for it...or do i have to go side/down...thanks for all the info...im complete noob when it comes to converting this...but i figured id rather have a FI 12a then be another TII swap...thanks..parker

 

this fits the RB holley intake. woot!

it's made by autonomics and costs 345.00 for this kit w/out injectors.

http://www.auto-nomics.com/cgi-bin/s...part=12168-001

 

Nice! Where does the injectors mount? I'm considering letting go of my boost prepped weber and going FI.

Thanks, Ed

 

look at the picture you see the fuel rails beneath it you will the holes . this set up is pretty nice and yes you can run it with megasquirt but i would prefer the microtec lt8 .

 

If you've got $4k, that is PLENTY. If you go with Megasquirt, it will be cheaper and yes, there is plenty of support for boosting, but if you think you will like a more expensive or more capable ECU, then by all means use it instead. Don't settle for something you won't be happy with.
Having said that, however, I use Megasquirt and am very comfortable with it and I would recommend it.

There are many components to an FI setup, you just gotta start doing the homework, it is seriously too much to list and there's already lots of info posted on www.megasquirt.info, or www.msefi.com, even if you don't go with megasquirt...

 

so this guy i know has a centerplate he says for a 12at from jap, it looks like mine but has injector holes on the top, is there such a thing? and is $100 au a good price? ( plate is as new cond never run- old friend moved back from jap with all these odd parts)

 

Yes
I have a Jsec 12a turbo 100 is fine.

 

i once emailed Megasquirt and asked if their ECU could do sequential injection, but never got a response... at first glance, to me, it doesnt seem capable, whereas Haltech boldly advertises that it does sefi...

sefi would gretly improve the effeciency of a ported engine, as gasoline isnt in the intake air that gets blown out the tailpipe during the overlap of the ports.

but haltech is pricey, so im gonna try to build my own out of old UPS's and free samples from the internet.

interesting sidebar: a dodge 2.2L ecu cuts fuel at 6600rpm... if you dont like redlining the engine, the TB will fit with minor modifications, and it controls spark advance, idle speed and electric fan as well. there isn't a shortage of doge ecu's at the wrecking yard either.
but 6600 rpm sucks.

 

You "emailed megasquirt"? Who exactly did you email because there is no "megasquirt". It primarily consists of a group of people that contribute to the evolution of the project. If you want answers to your questions do an internet search, it's pretty easy. Are you mad 'cause you think they ignored you or something?

The older version of the MS ECU doesn't support sequential injection. The new version may, but I haven't followed its progress. I don't see what you're saying about ported engines running better with sequential. Sequential's primary advantage is at low engine speeds and idle. The effect on horsepower is minimal, at best. If you got fuel coming out the exhaust it's not a "batch fire problem". Just tune the car better.

If you want the name haltech on your car, go right on ahead and spend the money. Seems like a good product but I've never owned one and probably never will. I would rather spend the money on other mods, but to each his own.

 

"You "emailed megasquirt"? Who exactly did you email because there is no "megasquirt". It primarily consists of a group of people that contribute to the evolution of the project."

maybe thats part of the problem then... no im not mad, i was just cruising for information, and with the lack of it i made the only assumption i could. i found no reference to SEFI with megasquirt when i checked google either. my bad.

on a stock piston engine there is overlap between the exaust and intake strokes because the airowing out of the exaust vavle scavenges air in through the intake valve. with a carbeurated piston engine, any air flowing into the engine has gasoline mixed into it, therefore the air blown out through the exaust valve has precious gasoline in it.
batch firing leaves gas sitting in the manifold waiting to be sucked in, and consequently partially blown out.
by properly timing the firing of the injector in SEFI the gasoline can be injected after the exaust valve closes, thereby eliminating wasteage of the gas.

now with a stock rotary engine, the overlap between exaust and intake ports appears to be minimal (looking at the half engine i got in my room) but with more aggeressive porting and reduced exaust restriction, the same as above should begin to take effect.

as for haltech, i only mention it because i KNOW it does SEFI.. i hate paying for electronics and id rather build my own ECU out of old computer perhipherals and some free samples off the internet.

 

That's weird, it came up for me. Oh, well.. If you wanna read about it go here: www.megasquirt.info and www.msefi.com search for sequential on the "info" site, it has some specific info.

MS has huge Internet support and is very capable. I hear what you're saying about sequential injection, but sequential is really not that important.
There is overlap regarless of the porting, even on stock. Big enough porting and no intake in the world will prevent it.
Certainly, at idle/low RPM sequential is more efficient, no argument there. But how much more? My argument is: not much. Also, it takes more effort to tune correctly, and if untuned it won't be any better than batch fire.

Further, for sequential to be effective you need to have injectors directly on the port. It's useless for people (like me) who go with aftermarket TBs and ditch the primary injector slots as the fuel is so far above the intake port timing would be difficult to tune, at best..

 

jayroc you sound like you know a bit, with this centerplate and it's holes in the top for injectors. Can you tell me what this does for porting as mine is a bridge and what is the process called, i understand i will be re- building the 12a again but thats ok, what stationary gears and which rotors do you suggest, i can't find a walk through conversion on line so a link to a guide for this job would fix everything. thanks guys.

 

Honestly, I don't know, really. I never worked with ported engines.
I also don't know the specs for the 12at center housing and whether or not the port timing is close or the same as a normal 12a center iron, or even a 13b center iron... that'd make a difference.
There should lots of people in Aussie-land that can help with that..

Stay cool, I heard it has been hot as hell down there lately.

 

"Further, for sequential to be effective you need to have injectors directly on the port."

damn right, unless....

*crazy mode on*.. you pop a perhipheral injector port into the top of the rotor housing! then you dont need SEFI at all!

I've also had ideas about a direct injection rotary using the trailing ignition holes for a spark-plug styled injector. i havnt done enough research as to which injectors yet though, or a fuel pump.