decision time!! carb or efi
 

I have been looking at both sides of the story. I have done my searches. I still have some doughts. I have just finished rebuilding 13B 6port. In the future I want to go turbo. I have been thinking about going with the EFI for some time. I think that the tunning options are more easyer for me. I was looking at haltec and a few others. I still haven't asked them for a specific unit. I am thinking that I don't need the complete harness if I get a stand-alone unit. I only have a few hunderd buks to spend. I needed to spend 1500 on the body (chassis rot) I still have a workable 12A all-though its got a blown apex seal in it. I am going to rebuild it soon.

My questions at the moment...

Anyone know of any manufactuers that make stand-alone management computers?

Should I sell the freaking engine and get a 13B-4port?


fyi.. its an 1985 13B from an -se thats going into a previous home for a 12A

all positive replys are appreciated. Thanks in advance for everyone support!

go EFI!

microtech, haltech are relatively inexepensive and work great.......

Definitely EFI if you can afford it.

EFI, save yourself the hassle.

humm.. so all i'll need is the harness for the engine? or will I need more stuff then that? If so I will go with the EFI. thanks all

megasquirt it! the guy who said microtech and haltech r inexpensive is nuts!

you need a few things besides the computer and harness but you can reuse alot of the stock efi components.

once you price in a new carb/fuel pump/intake manifold/etc. you are at the same price as a standalone......

you could carb it for 600 or less. but it's a tuning nightmare from the beginning. make sure you have a damn wideband if you go carb! dont get a weber either, they stopped making 48's which would be perfect for you setup and it's expensive as hell for the tuning pieces you will need. if you go holley it will be cheaper and easier although some say setting them up is harder. we'll see. honestly, if i could do it all over again tho, i would have gone efi.

humm.. what are you saying? You need a wide band O2 sensor for a carb set up? I thought you only need something like that for a EFI set up?

Are there certain units that are easyer to install or are just plain as night and day.. better than others?

I have the harness for the engine, when getting a EMS.. DO I need a certain harness?

You'll probably need a wideband for either carb OR EFI. It's a tuning tool.

Megasquirt is by FAR the cheapest. ( www.megasquirt.info ) It's a few hundred. The only catch is that you have to build it yourself. (But that's half the fun.)

As far as a wideband, there are several options.

There are many good models available from Tech-Edge ( http://www.techedge.com.au/ )

Also Innovative makes a good model, prebuilt, standalone... Designed to work with a fuel management unit. http://www.innovatemotorsports.com/x...me.php?cat=253

There is also a company that'll make a custom harness for your engine with all the EFI bits. The link and name escape me at the moment though.

Advantages of efi are more power [7-10%], better fuel consumption[around 5%], smoother running, easier to start especially when very hot or cold. Easy to turbo later. Cost in if you do not have them: the ecu, injectors, upgraded fuel pump and lines, surge tank.

Advantages of carb are its cheaper, simplier to install, easier to fix if it goes wrong, it's what real men use.

I have two 12A powered cars. One has a modified Nikki, the other is efi. using Microtech. The latter is clearly far better all round, and while it costs more initially to install, over three years fuel savings will pay for it.

Thus, if in the medium term you intend to keep the car, going efi in 98% of situations is the way to go.

i prefer..... www.plxdevices.com

:D

ive been doing the exact same swap for the past few weeks, aslong as you get the engine harness and preferably the front harness aswell its pretty much plug'n'play. however i dont have the front harness. i will be doing a write-up on this swap if she ever starts! im damn close now tho.

staying EFI has a lot of benefits, mostly gas mileage and more tunability. the downside is if you want to do it properly with the front (dash) harness you will end up yanking the dash... altho on these cars it doesnt look too complicated. i may end up doing this if i cant re-wire the stuff myself since i already have a full engine harness connected.

im sort of in the same situation as you, and i keep getting fed up with the EFI system thinking i may aswell just get a carb. but theres still a bit of fight left in me!

Changeing the 'dash' harness is exactly what I don't want to do. Everytime I remove a interior peice its hard as hell to get back in the same place looking the same way. I figure if I spend the extra dough and get a stand alone unit I will not need that harness. Thats why I really need to know if I need it for a stand alone EMS.

thanks for that info pele
I am sure those links will come in handy.

I guess the easyest route would be to change the inside wireing harness and get the -se ecu.. I can get both for around $350 or so. Still if I have to spend a few more bones to get easyer tunening and quciker installation, then I will.

My megasquirt kit arrived two weeks ago and the car started yesterday for the first time. It's been fun to build, fun to learn (if you like research) and it's so nice to have an ECU that actually tells you whats wrong as opposed to just throwing a code.
Grant

can anyone thats running the megasquirt tell me exactly what parts I should buy?

As long as you have injectors, intake and wiring all you need to buy is the megasquirt kit, stimulator kit and thats it.
Grant

read here: www.megasquirt.info or www.msefi.com

unless you have significant mechanical skills and an intimate knowledge of 12 volt DC electronics i wouldn't attpempt a megasquirt build/install.

there is a significant learning curve involved in a projcet like that especially if you have no experience tuning.

from your description of the car it sounds like you still have quite a bit of work to do.

if you are building this car from the ground up and are still at the point of deciding between EFI and carb then you will need a serious parts budget to do wither one of them properly. If you are intent on going with EFI then you will need the manifolds from an EFI setup with all of the appropriate hardware. if this car was previously carbed then i would suggest doing this the easy way. i would get a high volume low pressure fuel pump meant for a carb and run the fuel into a surge tank mounted on the firewall. i would then run a high pressure EFI fuel pump from the surge tank to the fuel rail and send the fuel rail return line back to the factory fuel tank with a rising rate fuel pressure regulator in between.

once you sort our your fuel delivery you're going to need the supporting hardware like intake manifolds and fuel injectors. whichever engine you go with will determine the remainder of your required parts.

look at spending 2000 to 2500 on parts and tools for this project. the 12a will be more costly to consvert to EFI as there are quite a few parts that you will need.

Ray

Sorry, but I couldn't disagree more. I have no electronics knowledge and my total cost including buying a second-hand 13B and laptop has been under $900 Canadian. I have virtually no tuning skills but I'm doing it all by trial and error and it couldn't be easier. As long as you practise soldering and read everything you can you really can't go wrong. An -SE engine would be even easier because you don't have to deal with staged injection so you can just run the basic code. It all comes down to preference but I seriously wouldn't put this past anyone capable of pulling and replacing a stock engine (which I found harder than the megasquirt install). I actually spent more time soldering my broken radiator then I did my wiring harness. I may not be done the project, but I am at a point where I can comment on the difficulty of doing this.
Grant

I'm with grantmac, just built my first Megasquirt a few weeks ago. It was harder to follow the ordering process on the website than it was to build. I had no soldering experience with circuit board stuff and I still think this thing runs on FM (F*cking Magic) but its on my desk in front of me flashing lights on the stimulator. The further you get into it, the more you learn, and all of a sudden when you're reading on the forum you realise you understand whats being said( a little!). I've never had to wait more than 15 minutes for a little help on the forum. But that was after I had spent an hour searching first, and learned something else along the way. I say buy a $9 soldering iron and go for it, or search ebay and buy one complete. Get the rest of what you need from the junkyard(sensors etc.).

I did have some exposure to a Haltec when it comes to tuning efi. Typing on a computer is easier than fumbling with jets any day, and way more accurate.

The laptop I use cost me $50. It was cheaper than buying a new battery for my other laptop.

one part of your post i don't agree with... u don't need a EFI intake to do EFI... u can do it via a holley style intake with a holley style throttlebody(which i have found, 750cfm, for 75 bux), or via a weber style intake with weber style throttlebody... i've seen the weber style done, its on the code blue's SC 13B setup... pretty nice setup... i personally am going to be doing the holley style since i already have a RB holley intake manifold... and i'm gonna megasquirt it...

thanks Ray. at the moment I am working on getting my door fixed. why? well i had just like to drive the car out the garage with the door open, thats all. I have both, 12A and 13B. 12A is dieing. 13B is in peices soon I will be putting it back together. I don't like to rush things. especially something that I will be able to take pride in. Not to mention have my son learn a thing or to0. I am going to the bone yard again on saturday. I hope the find a -se with some doors. thats my number one priority now. While I am there I will see if I can pull the harness off. everytime i think i am ready to drive around the block.. there allways a freaking set back.

to be honest I haven't thought of fuel supply. I guess, i was guessing on getting a high pressure fuel pump and from there go into a fuel pressure rugulator and then to the fuel injectors.. thats as far as I have gone.. at the moment. i hate when theres an aspect of soemthing soo ccritical left out of an equation.

Yes, an EFI setup is a big project if you don't know what you're getting into. I got into a little trouble with it, and now I'm selling my stuff off. :-/ Check the classifieds if you're interested..

The holley TB you're talking about is much more expensive than $75 if you want it working properly, though..
About $375 for all the fixins, except air cleaner setup. It's a NICE setup, though, and an excellent deal. I plan on buying one eventually.

I'm more of a carb guy, one day i will build that majorly brideported engine that will need a holley 900cfm. the secondaries wouldnt have to kick in until 7k.

http://www.auto-nomics.com/cgi-bin/s...rt=10850-002-D

and yes, i understand it still needs 2 fuel rail, some injectors, probly a throttle position sensor, but use TII injectors with that and u won't have to spend a ton...

ok, maybe i was a bit pesimistic on my original post but i think a lot of crucial information is overlooked when the only that is posted is "how easy this is"

you're right, the 12a doesn't need EFI manifolds - i've been in this game for far too long to try adapting 13B EFI parts onto a 12A. I would start with a downdraft carb manifold and go with an InjectionPerfection TBI. kits can be found that contain 4 injectors, TPS, throttle body, velocity stacks, and fuel rails - ALL IN ONE! talk about a sweet looking setup!

while there are guys out there that swear by the megasquirt kit i'm still partial to the microtech units. the available add-ons and tuning features of the microtechs still impress me. and yes, before anyone trumps me on this i do have a previous relationship as a dealer for microtech - there, now my bias is in the open :-)

when it comes to a project like this planning is the MOST IMPORTANT part!

always give yourself options and realize that some parts of the project will become expensive.

my opinion of junkyard parts, especially wiring harnesses, is pretty low. the youngest SE you're going to find in a junkyard is now 20 years old. 20 years of age, neglect, repair, and sometimes abuse are going to take its toll. if you want to go EFI and your car was built for a 12A i would suggest leaving it a 12A and using an already available aftermarket kit such as the microtech or haltech unit that comes with an already constructed wiring harness. if you want to purchase a bundled kit that includes almost all the parts you will need to convert from carb to EFI i will be more than happy to help you with your setup.

pull the engine, rebuild it and design your EFI system. if you need help with the design process be sure to ask. an organized list of parts is crucial!

pm me if you have any specific questions about planning your project.

Ray

hehe... TII injectors are at a premium right now. most of the import crowd has realized that turbo rotaries are thirsty and require big injectors from the factory. 550cc injectors are seeing a big demand right in everything from civics to supras.

Ray

I decided to do the change over from Carbed to efi/ecu. "Microtech" on my 79 supercharger. Its not cheap, but well worth the switch. I have a 13b 4 port. If you have any questions on the goods and bads catch me on aim or pm.

motec!!

just for now i think I am going to throw the 13B in and make as close to stock as I can get it. If I can get the stock harness and ecu in the bone yard thats what I am going to roll with for now. While I wait for my rex account to get fatter, this will allow my plans to mature to the point where it can just fall off the brain tree.


At the moment I am looking to up grade the fuel system. I have found various choices :

http://store.summitracing.com/partde...=KeywordSearch

edit.
in a word.. overkill.. http://store.summitracing.com/partde...=KeywordSearch

i guess finding a complete ready-made-tested system for fuel delivery isn't that hard... or is it? will the first one work just fine?

why are you gonna spend that much?

Well, I have to suggest carb if your not planning on using lots of boost (under 15 psi). If you use a holley setup, boost preping the carb is very easy and tuning a holley is easier than anything. Everything is readily accessable by removing the fuel bowls. From there its just as simple as taking out a screw and replacing it. just get a full set of tuning parts and your set. It takes time to tune a carb, but IMO its much easier.

i went with a holley setup on my SP 6 port 13B, but thats only a temporary solution till i get everything i need to go FI, then i'll take some time to FI it, and hopefully be running with minimal down time, tho with my record, nothing goes as planned, and down time will be huge lol

interesting...

the first pump you picked out is a low pressure pump meant to be used with a carbed system. that pump won't work in an EFI application where your rail pressures need to exceed 40psi.

i would reccomend these pumps:

Bosch Fuel Pump part number: 0580 254 044

-or-

MSD -2225 http://store.summitracing.com/partde...3&autoview=sku

these pumps will flow a great deal of fuel at the required pressure and will also work when you start building your turbo system. you can source most of the plumbing locally or purchase it directly from summit as well. you're on your own for locating the bosch pump - most bosch dealers will be able to find it for you though, just give them the part number.

next you're going to need a surge tank/swirl pot. the swirl pot is designed to serve two purposes. it serves as a buffer between your unbaffled factory fuel tank and the increased flow requirements of the EFI fuel pump and it seperates the air from the fuel. by swirling the fuel inside the tank it sends the heaviest, most dense fuel to the boundaries of the tank, leaving the lighter fuel and air in the center. this gives you a more consistent fuel pressure and density than most standard systems. assuming there is clearance under the hood i prefer to mount that equipment on the firewall or the inner fender well for easier access. if you choose to mount this equipment under the hood you need to be sure that you insulate it from any source of heat - we all know what happens when gasoline gets hot :-)

if this car isn't going to be daily driven or expected to make a serious journey then i would suggest maybe a 5 gallon fuel cell to replace the factory tank. that way you can dump some weight and build a more "propper" fuel system.

the next most important part in your system will be the fuel pressure regulator, for that i would suggest this particular FPR:

Aeromotive A1000-6 http://store.summitracing.com/partde...0&autoview=sku

that regulator will serve you well in conjunction with the MSD fuel pump and again, provides the rising rate function desired for turbo applications.

after that it's all a matter of picking out the equipment you want to inject the fuel. since you are going with the SE engine i'm assuming that you'll also be using the SE manifolds and injection equipment which will make installation and tuning quite a bit easier. infact since you're using the SE stuff you will already have the fuel injectors, fuel rails, and fuel pressure regulator for the factory application and some mild performance tuning beyond that.

Ray

stock tanks are baffled... the 12A tank just doesn't have that bowl deal(can't remember itsname now) in the middle of the tank... we had a thread on this recently, with pics included...

On the holley setup, I'm just saying watch out for the extras. I've emailed and talked to the guy and this is what I'm basing the number on:

T-body 75
TPS 40
IAC 60
Machining-TPS 30
Machining-IAC 60
Adapter ring 15
Fuel rail assy 115
Total $395

Actually, it is a bit more, but at $400, it's still a sweet deal. The TB itself has to be machined to accept the IAC and TPS. Of course, you don't NEED those two, but it helps in tuning. In that case, you could get by with knocking 190 off for the sensors solenoid and machining..
I have a set of s4 FC injectors and plan on getting them cleaned for $100, then finding a mani for $150 or so used.. ECU and misc hardware, if using megasquirt, would run around $400.. Cheaper maybe, if you're frugal or find a good deal someplace.. I have this stuff already, tho.
So, $1k for a very good EFI conversion is not unreasonable. Cheaper if you got a SE and aren't going from carb.

But right now, I'm broke, so it's all just planning.. Trying to sell my old setup, ATM, dunno if I mentioned that.. ;)

Here is what my setup looked like http://www.mindspring.com/~wilkinsjr/my%20car%20pics. Engine bay is a bit dirty.. Check the pics from February.

i did some searches and found this

http://toyotaperformance.com/surge_tank.htm

i wonder if this will work? also is that best way to rig everything up?

I bought a side mount tank from tweakit. Worked out well. Had to weld on a fitting to reduce the output barb to 5/16, though..

hm i was figuring on trying to find a GSL-SE tank, but it might just be easier to do a surge tank setup... GSL-SE's aren't common here in WA....

in my opinion, the surge tank method is always the easiest way to do it.

Ray

personally i'd go carb just because i think it's cooler.
i don't think many of us drive our cars everyday, so stop bitching about gas mileage.
everyone goes FI because it's the obvious thing to do, it's better, that's why carbies are so cool, no one does them, and when you are faster than FI, it's just that much cooler.

kind of like old ford flathead engines. SLOW. However, i've seen guys supercharge them and run 12's.
sure other engines can be faster, but half as cool?
hell no.

maybe u don't drive ur car every day, my FB is gonna be my only car till i can get another TII... and then the TII will be the daily driver, FB will be the auto cross project car lol... theres nothing cooler about carb's, unless its cool to not atomize fuel well;) lol

When did they stop making 48s??? you talking about the dco dcoe or ida?

there is a place that sells weber style throttle bodies, it is www.twminduction.com. I want that setup.

in reguards to http://toyotaperformance.com/surge_tank.htm

whats is the efi pump? is that something that comes in the engine all-ready? At work I am going to make a surge tank just like the one in the description. I hope they got more metal in. I am thinking of adding sometype of air bleeder on the top of the surge tank so that I can release any air build-up that might accumulate.

as for the rest..
I am going to order MSD -2225 and Aeromotive A1000-6. I am going to try and go with the stock system for now, meaning I am going to the boneyard this weedend to hopefully find a door. while I am there I am going to try and find a -se wireing harndess(the inside one) and also a stock computer. If I can not find them, I will get the megasquirt.

air bleed? i don't think thats a good idea... as for efi pump, that means fuel pump... u need one for EFI, carb fuel pumps don't push enough psi, as has been stated inthis thread probly 5 times on every page...

the EFI pump is simply the high pressure fuel pump for the EFI system. also, make sure you get an EFI fuel pressure gauge so you can accurately set the pressure of the system.

i would advise against building in the air vent into the surge tank. an air vent is going to allow fuel vapors to escape the system - you don't want this to happen, especially mounted under the hood. any air in the system will be returned to the fuel tank via the return line. if the tank is constructed properly then there will no worries of airation.

in this case i would reccomend building your tank to slightly larger than the specs on that site. the extra capacity will come in handy when the accelleration loads of the 13B outstrip the fuel flow capacity of the stock fuel pump that was designed for a carbed 12A.

before you order any parts do me a favor and give me a complete catalogue of parts that you already have and that you plan to acquire. the last thing you want to do is buy parts that you don't need or can't use.

Ray

dude, there is nothing cooler than having 2 sidedraft horns grinning at you.
i simply feel my project to be a excercise in the utmost simplicity. there is something beautiful about having no electronics and only 1 or 2 lines to clutter the place up. :boink:

u can have that with FI;)

I'd like to jump in and say the megasquirt is a good option... the megasquirt itself, w/o the stimulator, is only about $140 for a kit, or $300ish pre-built. Setup is well documented, and the tuning instructions on the megasquirt site are written as if the person reading has never tuned anything before... so if you've never done this before, there is nothing to worry about.

I'm helping my friend (Tofuball) megasquirt his 13b 6port (s5). We're using the msns-extra firmware on the megasquirt, and a techedge wideband. We're using AFR tables, letting the megasquirt control ignition (right now with a hack-job GM HEI ignitor and the stock leading coil, but after tomorrow, we'll be using a stock CAS, and stock leading coil, with trailing coming in a few weeks), megasquirt controls the aux ports, and VDI as well. We're also using the staged-injection code to handle engaging the secondary injectors... ALL of it works great, so far... and we've revved up to 9000 rpms at full throttle with no problems (well, the HEI module fried but that's the HEI modules fault, not the megasquirt's, and we won't have to worry about that once we move to a fully stock ignition).

Anyway, my point is that several people have the megasquirt running their 13b's without problems.