I have an Australian 1982 RX7 (SA22C6.......). The original 12A has been ditched in favour of a 13B, one of the cheap turbo imports. It has never had the turbo fitted since I've had it, just the 4 barrel Nikki. The motor has been rebuilt, 2 years ago, with high compression rotors and a mild port job done.



Now I want to ditch the carb, and go with fuel injection, with an aftermarket ECU. I'm an electronics engineer, soI'll probably build a megasquirtAVR to run it.



I spoke to my local wrecker about getting an EFI inlet manifold, but was told the primary injectors are actually in the block, so it won't work.



Can anybody offer any suggestions on where to go from here.



Thanks inAdvance.



Amanda

try this question in the main topic rather than FAQ's. That way it will get more traffic.



Your wrecker is right on the money though, the primaries are in the block.



Why do you wanna go EFI?

The carb is a PITA. It's had 2 major rebuilds in 2 years, and the choke circuit has never worked. Part of it isn't even there. I have to stick a peg under the choke knob to make it stay out. It's not so bad in summer (now), but winter is, well, a pain. And the MegasquirtAVR looks cool, I've just gotta put it on something.



I'm currently thinking of going with throttle body injection. 1988 Ford Falcons here in OZ had them. They're like $50.00 from the wreckers. Don't yet know what cfm they are though. By the look of them, I think I'll need 2.



They should sit nicely on top of a manifold from tweakit, with custom adapter plates. Add a surge tank, a pump, some sensors, and I think I'm getting somewhere.

haha a peg!



Where in aus you from?

A peg https://www.nopistons.com/forums/pub...1047683785.gif. I like that, a girl with an engineering thought. I once use to use pegs to hold all my wiring for the stereo together in the car.

I'm in Sydney.

Looks like there's a few Aussies on this list.

I shifted this thread to 1st gen spec to get more traffic.

just use a stock manny, the turbo manny will flow realy well.

ooh yeah. get one of these!

if u have a 23B that came off a turbo car, the center iron should have the injector ports in it. the only 13Bs that didnt bring them were the 13Bs from the 70s...

So unless when it was rebuilt, they used a diffrenent center plate, you should already have the injectors in the block.

Uhm...i think...I should ditch my carb now...

if his was a turbo engine it should have em. theyre prob blocked off with a fuel injection plug kit

theres a slight coolant o ring incompatibility issue with pre FC engines and FC engines.

off topic, sorry, but i would die to live in australia. its always been my dream destination. anyone have a spare house? https://www.nopistons.com/forums/pub...DIR#>/wink.png

Those throttle bodies sure look a treat don't they?. At over $1000AUD (including the manifold) they'd want to.



Sorry, over budget.

https://www.nopistons.com/forums/pub...1047683621.gif only slightly off topic LOL

What makes you so desperate to live here?





Back to the topic,



Amanda: do you have the injection plugs in the center plate?

oooh, amanda. in that case ask all u want.lol



u need pics of that fuel injector plug installed and what the engine would look like with out the plug kit??





https://www.nopistons.com/forums/pub...1047683621.gif theres a nice girl here at work named amanda soon ill ask her something not work related.lol

https://www.nopistons.com/forums/pub...1047683621.gif I know a swimsuit model from australia, she was born in kentucky then moved there.



Topic: Stay with the carb alot easier to manage, just a little more hassel

Hey cool, I'm from Kentucky... heh



Where'd you get a 13b manifold to fit the Nikki to? A '70s 13b I guess? If, in fact you are using a '70s manifold and you don't have injector plugs in the center plate, then you have an older 13b. A couple of things to look for to determine this are the mazda logos on the rotor housings and wether or not there are fuel injector plugs in the intermediate housing. Unfortunately, I can't find a picture of the old school 13b rotor housing logos, so I'll leave it to you to search. https://www.nopistons.com/forums/pub...#>/biggrin.png

I mention this because if you don't have injector holes and you you want to go EFI, you've got a lot of problems to overcome. As I'm sure you're aware, but in my opinion it will take a significant amount of time to convert properly and is not worth the gains unless you're going turbo, and with high compression rotors, you won't be able to boost that high...

If you still want a NA with EFI, then you may want to consider getting all the parts from a junkyard 2nd gen. ECU, harness, manifolds, fuel pump, etc. You'll save a lot of time and money. However, since it is likey that you have an old 13b style intake manifold, you won't be able to buy anything from a later model rx7 because it won't bolt on and you need the injector holes. I know you've done this already, but there might be something that will work, depending on what type of manifold and intermediate housing you have...



BTW, what do you have against carbs?

If your choke knob isn't staying out like it should, it's likely a problem with the electromagnets that hold the choke knob in place.

What I mean to say is that the engine bolt pattern is different...

Also, I DO think it'd be worth it to covert if you could get all the parts from a later model 13b, but I don't think there's a lower manifold (stock mazda, anyways) that is EFI and will bolt to the '70s 13b, but I could be wrong..

This kit from Racing Beat says it's for 6 port engines. Mine's 4 port. Anyway, can't see anything like it on the block.



I'll fire up the digital camera shortly & get some close-up photos.



Amanda

Just found this in another thread.



http://www.mazdacomp.com/fuelinjection.jpg



My existing setup appears to have a 3/4" thick plate between the manifold & the block. Me thinks I could replace that with one of these, and use my existing carby as the throttle body.



Amanda

if my car wasnt covered in snow/ice id take some pics....if your 13b was from the 70s, it was carbed, it wouldnt have the fuel injector plugs, it would be a 4 port and i believe it would say mazda on the rotor housings. if it came out of a car from the 80s, it was fuel injected, either 6(NA) or 4 port(turbo).



that fuel rail looks pretty good. just make sure that it fits the LIM bolt pattern.

YES, it has Mazda on the rotor housings. I take it then that the later motors didn't?

Build someone an ECU, in exchange for them building you a custom manifold.



I'd like to see one with one of these from a Mustang on it.



BBK Mustang Throttle Body



Or these from a Camaro. Should be easier to split airflow front / rear.



LT1 Throttle Body

All rotor housings say mazda on them, the 70s model looks different, though.

Actually, I think it looks cooler..

Anyways, snap some pics and we can tell you more...

https://www.nopistons.com/forums/pub...#>/biggrin.png

u know after i posted about that i was trying to figure out what exactly the difference was...im still looking for old school housing pics to post up.

but if i rememeber correctly, the MAZDA size and font style is larger about 3/4 to 1" in size as opposed to the newer bout 1/2" size. as soon as i find some pics ill post them...

Finally, I found some pics!

http://www.rotaryresponse.com/ebay/MVC-475Fopt.jpg

From: http://rxforyour7.com/mazda%20rotary.htm

The later housings will say MAZDA and 13b (or 12a, depending..) on them as well...

can anyone tell me what the downdraft efi thing on the first page of this thread is? like what is it, who has it? thanks.

They're made by tweakit. The agent here in Australia puts them up on ebay.com.au. I think it's AUS $854 and a manifold to suit another AUS $250. Then you need to buy the actual injectors themselves.



http://cgi.ebay.com.au/ws/eBayISAPI.dll?Vi...&category=32624

Here's a photo of the logo on my housings.

i have what you need. check out www.KGParts.com under intakes. there are plenty of other setups that i just dont have on the site. https://www.nopistons.com/forums/pub...IR#>/smile.png