Page 1 of 1
Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 11:14 am
by harrymr2d
What's up guys! I purchased a 85 AE86 with Mikuni carbs already installed 1.5 years ago and currently looking to make back to EFI. I drove the vehicle 1.5 hours back to PA from NJ and she drove good with no issues at all. I am looking for advice on what might be needed to return back to EFI and what am I up against. Fyi I won't be the actual work because I don't have the skills point blank : ( .

Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 11:45 am
by yoshimitsuspeed
Need more information.
Are you going to stock engine management? Or Aftermarket?
Was the car originally EFI? If so how much of the original wiring is there?
If not then how is it currently wired?
Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 12:25 pm
by harrymr2d
Stock engine management and yes it was original EFI 85 GTS, unsure of the wiring. Car is currently at body shop and will have to wait till I go back.
Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 1:17 pm
by 1234AE861234
You'd need the entire airbox set up from intake flange to air filter. fuel injectors and all the appropriate wires for those parts to work properly, and probably a new distributor too if your current one is "locked out" on a certain timing. But The main thing you need to look for is how the injector ports were plugged up. Hopefully they weren't welded shut like my carbed 16v

Sent from my iPhone using Tapatalk
Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 2:23 pm
by Grant
1234AE861234 wrote: But The main thing you need to look for is how the injector ports were plugged up. Hopefully they weren't welded shut like my carbed 16v


Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 2:25 pm
by harrymr2d
My luck they be welded shut : (. I should just swap something else in or leave the set up
Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 2:29 pm
by 1234AE861234
If it's welded then just leave the set up as is or sell the entire set up and swap in something else
Sent from my iPhone using Tapatalk
Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 3:07 pm
by yoshimitsuspeed
It really depends on what your goals are.
You could just get a donor motor or just source the parts you need.
Throw another head on there and sell the head and carbs as a ready to go setup.
Or you could look at swaps but you can do a lot with the 16v depending on your goals.
If it was me I would do anything I could to get EFI back on there.
Re: Removing Mikuni carbs returning back to EFI
Posted: Sun Feb 15, 2015 3:25 pm
by oldeskewltoy
intake manifold
TVIS plate with all components
rwd throttle body
AFM and airbox, or pod filter
intake tube
vacuum lines correctly routed
EGR system - valve and hardware
BVSV valves

Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 12:17 am
by Toy86
Why do you want to go back to EFI? If the car runs great with the carbs, why not keep them and keep building apon that platform. If the quest is for more power u still have a nice set up get more out of the engine. Just curious on why you would want to make the change back, there's quiet of few ppl on here that would love to have a 4ag w/carbs instead. lol
You would also need your:
Ingnitor Coil
Ingnition module
Chances are you'll probably need GTS Engine bay wiring harness and ECU
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 9:34 am
by yoshimitsuspeed
Toy86 wrote:Why do you want to go back to EFI? If the car runs great with the carbs, why not keep them and keep building apon that platform. If the quest is for more power u still have a nice set up get more out of the engine. Just curious on why you would want to make the change back, there's quiet of few ppl on here that would love to have a 4ag w/carbs instead. lol
You would also need your:
Ingnitor Coil
Ingnition module
Chances are you'll probably need GTS Engine bay wiring harness and ECU
Why would you replace your typewriter with a desktop computer?
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 10:42 am
by mideng
Obama says if it is not broken why fixed it! US Economy sucks but its not broken why fixed it!
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 2:53 pm
by harrymr2d
My goals are simple just a good running weekend cruiser with a little pep, I have had multiple Ae86's GTS but never carb setup. The 1.5 hour drive was good but car didn't feel as responsive as my past cars and I am looking for over all
Reliability turn key and go. I would lIke to swap it out but if cost is too much them I might leave alone considering I would have to pay for everything: (
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 6:26 pm
by hachi-6 D0ri
harrymr2d wrote:What's up guys! I purchased a 85 AE86 with Mikuni carbs already installed 1.5 years ago and currently looking to make back to EFI. I drove the vehicle 1.5 hours back to PA from NJ and she drove good with no issues at all. I am looking for advice on what might be needed to return back to EFI and what am I up against. Fyi I won't be the actual work because I don't have the skills point blank : ( .

Hey I would be willing to trade my efi set up for your Carb set up
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 6:33 pm
by harrymr2d
Where you located hachi dori 6?
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 6:46 pm
by hachi-6 D0ri
harrymr2d wrote:Where you located hachi dori 6?
Huntington beach California
Re: Removing Mikuni carbs returning back to EFI
Posted: Mon Feb 16, 2015 7:59 pm
by allencr
harrymr2d wrote:...1.5 hour drive was good but car didn't feel as responsive as my past cars
What's the compression?
Really, You've go no real clue about its current condition and it's just a WAG that EFI will make it any differen at all.
Re: Removing Mikuni carbs returning back to EFI
Posted: Tue Feb 17, 2015 3:48 am
by harrymr2d
i don't know what's the compression is, I drove it home and parked it and it went straight to the body shop where it currently sits ( almost done ) yes didn't feel as responsive quick. I live in PA and would like to find somebody who really knows how to mess with the carbs on a ae86.
Re: Removing Mikuni carbs returning back to EFI
Posted: Tue Feb 17, 2015 8:04 am
by Toy86
Working with carbs isn't that difficult. Search in the archives for a write up that Dr. Occa did on his 4ag carb set up. He explains the fuel jets, how to set up the Air/Fuel ratio etc. You probably just need to tune them up a bit, and the car should feel a lot more responsive. Also, you need to check your compression and find out some specs on ur engine like what kind of head/block ur running. Normally with a carb set up you want a hi/comp engine, and just upgrade the cams, and valve train and you'll have a pretty peppy engine. Read up on some ppl builds/write ups on this forum and you'll learn a lot. I think in my opinion it would be a lot cheaper to do some upgrades to what you have and get the response that you want instead of going through all the hassle of going back to EFI. But it's ur ride, and ur choices to make. Good luck.
Re: Removing Mikuni carbs returning back to EFI
Posted: Tue Feb 17, 2015 8:27 am
by yoshimitsuspeed
I totally agree that he should check compression, timing and all the other stuff that equals a good running car but going back to EFI still has some significant advantages.
Yes he may be able to dial those carbs in to perform as well as EFI.
Until the weather changes, or until he drives up or down 1000 feet. Then the carbs will be out of ideal tune and no longer on par with EFI.
Then there are the other things like gas mileage, emissions, etc that EFI does better.
Re: Removing Mikuni carbs returning back to EFI
Posted: Tue Feb 17, 2015 8:36 am
by oldeskewltoy
having lived in Pa... some areas there are emissions requirements, and other areas there are not.......
Re: Removing Mikuni carbs returning back to EFI
Posted: Tue Feb 17, 2015 3:40 pm
by harrymr2d
Thanks to all you guys for all the valuable information. Once I get it back I will look into it more and keep you posted. I will keep you all posted. Wish me luck

Re: Removing Mikuni carbs returning back to EFI
Posted: Wed Feb 18, 2015 8:16 am
by Toy86
Here is the thread i was talking about:
http://forums.club4ag.com/zerothread?id=359. I know it says Ignition option for carbs, but it's 48 pages long and it covers also the jets and Air/Fuel adjuster for them. He's also running Mikuni's so that's a bonus for you, and who knows you might be running one of these ignition options that you can learn about. I spent a lot of time reading all this info cuz i was going to drop a 7ag with webber 45's side drafts, but i had to move so i had to sell my drift missile. Good luck and post ur build!