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-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   12a to 13b hypo (https://www.rx7club.com/1st-generation-specific-1979-1985-18/12a-13b-hypo-707366/)

wanklenoob 11-24-07 06:36 PM

12a to 13b hypo
 
I DID SEARCH! DON'T HURT ME! ok so if in the distant future I decided to swap out my good running reliable 12a with a fuel injected 13b, how hard is it to set up the fuel injection system, I have little experience with fuel injection, it's not a simple as the straight bolt carb. Also, is it a huge pain to rig up the 13b wiring harness? what are the different electronic controls in the 13b? (not planning anything soon, just speculation.)

85 FB 11-24-07 06:46 PM

Engine swaps are not as hard as you think when you have all the necessary parts. For a 13B, you pretty much would need the ECU and wiring harness for the motor operations. And, EFI is not as bad as you think once you know the workings around it.

bugman1973 11-24-07 07:57 PM

make sure you get the entire wiring harness all the under the dash part even for the rear storage bins and the fuel pump hook ups even the wire that goes to your dash head lights and front running lights if you dont it wont work. also you need http://i14.photobucket.com/albums/a3...r/100_0244.jpg this stuff

this is what it looked like after i got it donehttp://i14.photobucket.com/albums/a3...r/100_0249.jpg

trochoid 11-24-07 08:00 PM

Not only do you need the ecu and wiring harness, you need the ENTIRE fuel system, including the SE fuel tank and all of the fuel lines. The other option is to use a surge tank but the fuel lines need to be upsized as the carbed lines won't flow enough fuel for the FI pump.

bugman1973 11-24-07 08:02 PM

I'm referring to the two rubber bullet shaped actuators if you dont have them hooked up the fuel injection wont fire and you wont hear them click they dont actually click themselves but they make some vacuum system click that is for the emissions.

bugman1973 11-24-07 08:23 PM


Originally Posted by trochoid (Post 7546425)
Not only do you need the ecu and wiring harness, you need the ENTIRE fuel system, including the SE fuel tank and all of the fuel lines. The other option is to use a surge tank but the fuel lines need to be upsized as the carbed lines won't flow enough fuel for the FI pump.

you do not need the fuel lines and tank as long as you have a fuel tank out of any 84-85 rx-7. if your car is 84-85 dont worry about it if not dont even do the swap to fuel injection. all you need is the fuel pump. and maybe a fuel lines. i never changed my tank lines or anything i just made not of which one is the in line and which was the return line and i have a constant fuel pressure gage hooked up to both and i have not seen any spikes drops. nothing the tank and lines are a myth. i talked to lots of people about the difference in the tanks. the only difference in the in and out lines. all tanks from 84-85 have the baffles in them i don't know why some swear the dont have them but they are there. some people say that when the tank runs low that the engine will starve for fuel. i have had no problem being starved for fuel even when my light comes on i filled up the other day and put 13.34 gallons in it so it was pretty low. my car is an 85 so

i dont mean to make you look bad. if i did im sorry

steve84GS TII 11-24-07 10:01 PM

Sorry,I dont know what to tell you,but in my case thats dead wrong.

The tank I retrofitted came from a bone stock,good condition 85 GSL and it had no slosh baffle around the fuel pickup/return lines.I also ran my stock 84 GS tank for a short time while the 85 tank was being built and it didnt have any baffle cups around the pickup either.I dropped an FC fuel pump assembely into the 84 tank and it would cut out and drop fuel pressure anytime the fuel level was below 1/4 and I took a left turn with any kind of haste.Yes,they all have baffle walls inside the tanks,but in my experience only the GSL-SE tanks have the slosh cup that retains a pool of fuel around the pickup/return lines.

Wanklenoob......the 2nd gen EFI swap is not difficult,but you MUST have a basic or moderate knowledge of EFI operation before attempting the swap.No special tools are required and little to no welding is needed to make it work.The wiring is the hardest part,but it can be overcome with patience and the ability to read the factory electrical flow charts.....and the knowledge availible from this site.If your talking about installing an 84-85 GSL-SE 13B,then that is even easier since the SE engine is designed to go into the 1st gen,although the 2nd gen 13B's are a bit more powerful and a little more high tech(especially the 89-92's)

Jeff20B 11-24-07 10:09 PM

I got myself a GSL-SE tank for my EFI conversion. It unfortunately turned out to have water in it. :( I'll try the POR15 treatment. :)

trochoid 11-24-07 11:27 PM

I recommend the entire SE fuel system for several reasons. The SE has the largest fuel lines of ANY 7. The stock 12A supply lines are small and will make the pump work harder than it needs to, thus shortening it's life. The FI SE pump also puts out more gph than the the stock TII and the Walbro 255 lph pumps do.

There are 2 different versions of the S3 tanks, 1 for FI that has the sump cup, the other without for the carbed engines. If you don't believe me, I have a write up in the archives that shows the differences betwen the 2 tanks. Fwiw, all of our fuel tanks have baffles, which many seem to confuse with the sump cups. If one is going to go through the effort of changing over to FI, they might as well do it right like it came from the factory. This would include the larger fuel lines and the FI tank.

You can argue with me all you want, but when I do a project, I do it to the best of my ability and as correctly as possible. Doing it half way only causes more problems in the long run. Since most of the FI swaps into 1st gens are turbo swaps, a sump cup, surge tank or installing an in tank pump, with cup, like Steve has done, is a must.

Siraniko 11-24-07 11:32 PM


Originally Posted by trochoid (Post 7546939)
You can argue with me all you want, but when I do a project, I do it to the best of my ability and as correctly as possible. Doing it half way only causes more problems in the long run.

amen. There is no short cut in my book. :icon_tup:

85 FB 11-24-07 11:36 PM


Originally Posted by trochoid (Post 7546939)
You can argue with me all you want, but when I do a project, I do it to the best of my ability and as correctly as possible. Doing it half way only causes more problems in the long run.


:icon_tup: If you don't have time to do it right, you must have time to do it over.

kenn_chan 11-24-07 11:53 PM

agreed, and i fyou make enough HP eventually the sump cup will not be enough either. my sump cup worked up to about 350ish at the rear tires, I am now installing a complete standalone surge tank with pump and -8 lines to the front he, he, he (voc sotto) come here little GTR owner...... he, he, he......

kenn


Originally Posted by trochoid (Post 7546939)
I recommend the entire SE fuel system for several reasons. The SE has the largest fuel lines of ANY 7. The stock 12A supply lines are small and will make the pump work harder than it needs to, thus shortening it's life. The FI SE pump also puts out more gph than the the stock TII and the Walbro 255 lph pumps do.

There are 2 different versions of the S3 tanks, 1 for FI that has the sump cup, the other without for the carbed engines. If you don't believe me, I have a write up in the archives that shows the differences betwen the 2 tanks. Fwiw, all of our fuel tanks have baffles, which many seem to confuse with the sump cups. If one is going to go through the effort of changing over to FI, they might as well do it right like it came from the factory. This would include the larger fuel lines and the FI tank.

You can argue with me all you want, but when I do a project, I do it to the best of my ability and as correctly as possible. Doing it half way only causes more problems in the long run. Since most of the FI swaps into 1st gens are turbo swaps, a sump cup, surge tank or installing an in tank pump, with cup, like Steve has done, is a must.


Jeff20B 11-24-07 11:55 PM

trochoid's thread https://www.rx7club.com/forum/showthread.php?t=416682

85 FB 11-25-07 12:04 AM

This is why I love my -SE. These cars were made right! ;)

wanklenoob 11-25-07 11:47 AM

thanks for all the thoughts! I knew I could count on you guys for good advice! =D

bugman1973 11-25-07 12:33 PM

i have been planning on doing an in tank pump swap and also changing how things like my lines run. while I'm in boot camp ill have some built up money and two weeks to do some changes after i go to my first duty station im going to be home. so i was going to do the tank and a few other goodies like a shifter and some 6th port runners maybe a rebuild and a street port. i was just stating that things dont have to be all se parts.

P_Lav 11-25-07 12:55 PM

In my opinion, swapping out to a SE isn't a great idea, your bound to have a tonne of FI problems, as the SE's are prone to idle problems, and unless you know these engines like the back of your hand, they are a pain to figure out, I recommend you go with a S5 swap, or even a TII if your want even more power.

85 FB 11-25-07 01:01 PM

^ -SE's aren't as bad as you think. I own one and have yet to encounter any idle problems. Even if you run into an idle problem, there's a post in the FAQ section that helps narrow it down.

And, really, they're not hard to figure out when you take the time to figure them out.

diabolical1 11-25-07 05:08 PM

i was actually about to exit this thread and curse it as being redundant rubbish, but i think a very important point is emphasized here - especially for those with less experience and creativity. i think the points driven home by Steve and Scott (Trochoid) on SA/FB EFI fuel supply are invaluable and deserve to be somehow affixed to the archived material.

steve84GS TII 11-25-07 08:31 PM


Originally Posted by kenn_chan (Post 7547003)
agreed, and i fyou make enough HP eventually the sump cup will not be enough either. my sump cup worked up to about 350ish at the rear tires, I am now installing a complete standalone surge tank with pump and -8 lines to the front he, he, he (voc sotto) come here little GTR owner...... he, he, he......

kenn

I agree.
The sump cup has its limits when fuel levels are lower,due to its inlet ports at the bottom of the cup.Its a balancing act between retaining fuel from sloshing OUT of the cup,and allowing enough fuel to flow INTO the cup to keep the resevior full for the pickup.
The return line is purposely run into the cup to help with refill and prevent aeration.If fuel levels are kept above the top of the slosh cup's walls,there is no issue.But,when levels are low,a ridiculously high HP engine will suck up so much fuel that little juice is being returned to the tank, and the inlet holes for fuel flow into the cup are overrun......the slosh cup is your float bowl and the inlet holes become your needle jets of sorts.If your inlet needle cant flow more than your main jets,then THEY become the main jets and you will run out of fuel eventually!

Rx-7Doctor 11-25-07 11:27 PM


Originally Posted by bugman1973 (Post 7548022)
i have been planning on doing an in tank pump swap and also changing how things like my lines run. while I'm in boot camp ill have some built up money and two weeks to do some changes after i go to my first duty station im going to be home. so i was going to do the tank and a few other goodies like a shifter and some 6th port runners maybe a rebuild and a street port. i was just stating that things dont have to be all se parts.

That's not what you said.:)

You stated that you don't need fuel lines and tank as long as it is a 84-85 model.
As you can see by the correct information posted here, you were wrong.
You also stated that the tank and lines are a "Myth." You were wrong on this account also.

As far as you installing an In tank fuel pump. Why? Trochoid has already stated the facts concerning the capabilities of the Se pump.

trochoid 11-25-07 11:40 PM

On the subject of the slosh/sump cups, the FC cups hold 4-5 times the volume that the SE ones do. There is also no difference that I'm aware of between the NA ad TII FC tanks, other than the pump and filter socks.

The dfference in the cups is one of the main reasons I feel one should modify their FB tank with an FC cup and in tank pump. Not only is it more reliable in the long run, it's a hell of a lot quieter too

kenn_chan 11-26-07 12:31 AM


Originally Posted by trochoid (Post 7550206)
On the subject of the slosh/sump cups, the FC cups hold 4-5 times the volume that the SE ones do. There is also no difference that I'm aware of between the NA ad TII FC tanks, other than the pump and filter socks.

The dfference in the cups is one of the main reasons I feel one should modify their FB tank with an FC cup and in tank pump. Not only is it more reliable in the long run, it's a hell of a lot quieter too

thats what I did, and like I said it works great to about 350ish, my problem is not so much sucking it dry due to HP, its just I have spent more money on suspension upgrades/tires etc. than most.

I now grab enough gees at high enough speeds to make you light headed in a 180 degree 50 meter radius turn :) and that is when I am experiencing my real problems of fuel starvation.

kenn

bugman1973 11-26-07 12:35 AM

not wrong mis informed the tank does work the same just no slosh cup so what i have never had any hesitation from it at low fuel level even when the light was on the lines dont have to be changed though it is wise but they dont the hold the pressure that can hold even more pressure then what i am putting through them. when i did my swap the whole point of it besides not leaking oil was to do it as cheaply as possible to show that i can be done and not have any long term problems. i have had none except for a bad engine. not my fault found out it had way more miles than stated originally. i did my research. and tested everything before i posted this stuff. ive run the car for quite a few months with the 12a lines and tank. the se fuel pump is installed it works just fine no spikes in pressure. but now that i have done the swap i have changed my mind on what i want the car to be built for i want it to be more of a all around performer for the track and the street and saw somethings for the in tank pumps and thought i would get a better fuel system for the track out of that. thought about the second gen tank thought i might be able to get that too work better then the SE system. and maybe run a second gen exhaust system for the wide body i have planned. but i guess because i dont have as many years on me or been on this forum long enough that people just wont take my opinions seriously oh well i didnt get on here to make every one happy just to put some insite in to our cars

trochoid 11-26-07 02:51 AM

I'm not faulting you for trying, just for info that others may take as the best course when doing an upgrade when it isn't. Fwiw, the 2nd gen tank won't work, the filler is on the other side and the spare tire well would need to be completely removed. Even after that, the 2nd gen tank is taller and would hang lower.

If you want o be taken more seriously, you might work on your sentence structure. Your last post is painfully hard to understand.


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