Do-it-yourself fuel injection

Granny

Granny

One day at a time...
Joined
Jun 12, 2007
Location
Cabarrus County (Rimertown)
Since I started my build on Granny2 my plan has been to go with a Howell injection, and I am still looking very strongly at doing that. However, I am also getting more and more curious as to exactly what would be involved in doing a throttle body conversion using only (strictly) material you would get from the bone yard. Is it even within reason to attempt doing it? I know very little about fuel injection, but I also know there are some very sharp people on this forum so I have decided to start this thread with the hope of learning something new. BTW, I did search the forum and did not see anything else like this already posted.

OK... I know you need the throttle body itself. Then, you need the computer, a fuel pump, oxygen sensor, etc. That part doesn't appear to be rocket science.

Looking at the computer... I know you can buy a pre-fab wiring harness that's supposed to make the job simple, but my thinking is that if I have to buy a $300-$600 wiring harness then I may as well get a Howell, have all new parts and be done with it.

So... I guess what I am looking for is:

1. how many of the wires coming out of the computer will be used?
2. can the extra wires simply be cut off and disgarded?
3. what am I missing, and what else needs to be done?

I don't know where this will go, but I'm sure it will be informative. :)
 
There used to be a big following of using the Chevy Throttle body and wiring out of the 90's model trucks. I've seen some articles on them somewhere. I'll have to do a little digging, but it really didn't look too bad. It was stricly boneyard parts as well.
 
Granny said:
However, I am also getting more and more curious as to exactly what would be involved in doing a throttle body conversion using only (strictly) material you would get from the bone yard. Is it even within reason to attempt doing it?
Click to expand...

Yeap... I've done 2 (AMC 304 & 258) with mostly junkyard parts w/ a little new. The average has been $300 each. 99% of the info I used was gleaned from the Binder Planet "Injection Tech" forum. Bill Hamilton has been doing this for a LONG time and has the majority of what you'll want/need to know spelled out in the first post "FI FAQ...Start Here" is your best resource.

I'm not the be all/end all when it comes to TBI swaps, but it really isn't that complicated. Anyone that can read, follow directions, & knows which end of a screwdriver to hold *CAN* do it...

Granny said:
So... I guess what I am looking for is:
1. how many of the wires coming out of the computer will be used?
2. can the extra wires simply be cut off and disgarded?
3. what am I missing, and what else needs to be done?
Click to expand...

1. Most of them :D
2. Yes, my un-used wires are clipped 8" from the ECM plugs (just in case)
3. If you want the harness fit to be "custom", cut/solder/heatshrink every wire... otherwise, coil it under the dash

Holler if you have any questions!
 
Caver Dave, I believe you and I have touched on this before. I remember you telling me about the info on the Binder Planet, and I think I looked over, but just couldn't quite get the drift of it.

I will look at it again tomorrow, and then get back on here with undoubtedly a few (hundred) more questions. :confused: :lol:
 
What's the engine? Like he said, gm tbi can be done cheaply and easily as long as you know how to wire and plumb. Guaranteed there's a lot more info on the web on retrofitting a gm system than a howell anyway. If you've got the money to spend though, don't go with either...the howell jeep conversions are outdated and overpriced in my opinion.
 
Gm tbi swaps are pretty simple. If i recall you need the the o2 sensor, coolant temp sensor, tps sensor and the map sensor. The wiring is pretty simple. Just google search gm tbi retrofit and you will find no shortage of articles and write ups on how to do it.
 
Why not go with something out of a 95 or later 4.0 motor?

There will be an issue with the CPS. the tone generator is on the fly wheel. The mopar EFI kit that you can purchase relocates the cps to the crank pulley (new pulley), not sure if there are code changes in the computer.

But I will say that a 4.2 with the later 4.0 style OBD1 system is awesome.
 
About 15 wires, id stick with the 7747 ECM. Very easy to start tuning with. 15ish wires needed.
What's nice about a howell type kit, is it is a kit, all in one. Disadvantage is if you want to tune it to your specific setup, exhaust intake, cam etc... Doing your own chips you can really tweak it to your liking...
 
I'm no expert but I have swapped gm tbi onto two 70s f150s with 351m engines, I've also swapped a tbi 4.3 in place of a carbed 2.8 cherokee, swapped a mpfi injected 5.9 in place of a 4.0 grand cherokee, and an injected 1.6 in a samurai all for myself and my wheeling buddys. I'm a mechanic, so I work with these systems regularly.

I did not have to tune any of the tbi swaps as they ran great from the start, although they can be made better I'm sure. I'm just starting to look at the tuning aspect on my own truck.

If you have any questions about the swaps or wiring feel free to post up or shoot me a pm, ill give you my number and we could talk about it.
 
I did it on my CJ7, swapped a 89 4.3L Astro system on my 4.2L I6.
It can be as simple, or as complicated as you wanna make it. If you decide to do it from the boneyard , find a complete vehicle and get everything connected to the computer (harness, TB, and all the sensors)
 
Black Bear said:
Why not go with something out of a 95 or later 4.0 motor?

There will be an issue with the CPS. the tone generator is on the fly wheel. The mopar EFI kit that you can purchase relocates the cps to the crank pulley (new pulley), not sure if there are code changes in the computer.

But I will say that a 4.2 with the later 4.0 style OBD1 system is awesome.
Click to expand...


i agree with this statement
 
OK... I've been studying this stuff off and on all day. I just ran out to the boneyard (only a mile up the road) and the owner said he had at least 2 or 3 astro vans with bad motors that I would be welcome to rob parts off of. He asked me if S-10s might work as he apparently has a pretty good stock of them. Anyway, I have a hard time grasping the whole concept of an idea just by reading it once so I will need to study on it some more.

Thanks for all the input... and I won't be offended if it keeps on coming! :)
 
You could get everything off any vehicle with a 4.3, the sensors, and throttle body should all be the same. A van would probably have the better harness to grab since there is more wire between the engine and computer. That makes hiding the computer under the dash easier. A fullsize van with the v6 or astro should work.
 
Don,
I finally figured out and understand the GM TBI so I NO that you can! ( I no I misspelled NO but my cays and doubleUs are brocen!) Time to get a ne ceyboard lol
 
Any of the '89-'92 4.3L would be fine donors, provided they're using the 1227747 ECM (computer).

As you likely read, get *EVERYTHING* that remotely touches the the FI! Things like the OEM hardlines can be adapted to to provide a pressure test port & use OEM GM inline filters (though I don't like steel bodied filters... can't SEE when they need changing).

With both donor rigs, we grabbed the harness (clipped where it passes the firewall on the FUSE BLOCK side, NOT on the ECM side), the ECM, throttle body, fuel lines ('92ish trucks have OEM braided SS lines), & all the sensors (whether you plan to use them or not)

Sensors & assorted you'll want to snab:
CTS - coolant temp sensor
MAP - manifold absolute pressure measures the load on the motor
EST - elec. spark timing (ignition module similar to HEI module)
ESC - elec. spark control works with knock sensor to advance/retard timing
Knock - will screw into your block (replaces one of several water jacjet plugs)
O2 - screws into the header or exhaust
VSS - didn't use one on either install, but *MAY* work if needed and you'll already have it/plug
Coil - TFI coil with weird connectors
Oil Pressure - didn't use those either... assuming momentary low oil pressure won't let it run (layed on side :D ), but ain't gonna the engine for a few minutes

My install (AMC304)

Taters install (AMC258)
 
so im doing something similar, and have read over the stuff on binder bulletin...

my main question is about the distributor. I currently have a Large in-cap HEI distributor, and i can only find one instance discussing it there, and they say it wont work.

but then i found this:
http://www.viciouscustoms.com/TBI/junkyardtbi.asp.htm

not real sure if it will work. Dont want to weld up a good hei if it doesnt work in the end.
 
Keep in mind the BP folk may just have no experience with converting HEI?


paradisePWoffrd said:
Dont want to weld up a good hei if it doesnt work in the end.
Click to expand...

So, don't weld it!
Truth is, mine isn't welded... just safety wired between the 2 pins (on each side) the springs attached to.

If that scares you, just make a couple straps to hold each side and use "e"-clips (clipped into spring grooves on each pin) to keep them attached

:beer:
 
Here's how I did it myself. Bought a ZJ, stripped the motor and trans, put it in the CJ. Voila :driver: Seriously, I understand Granny's motor is great internally and he just wants an easy way to FI it. DIY, works ............................ sometimes! Howell works everytime :) My .02
 
...and Granny is still leaning toward the Howell for just that reason... plus, all new parts, and support if needed. If my friendly local machine shop subs a couple jobs to me over the winter I will simply order the thing and put it on. :)
 
And that was why i suggested the Howell system Don.
Good stuff for the $.
Just my opinon bro.........
 
Paul, I remember that well... but, as for starting this thread, I am still curious as to what's needed and how it all works. :)
 
Ben, That link is really good. Thanks for that info. Im following this because Don and I are on similar tracks with our archaic set ups.
 
I did the exact swap that you are discussing on my 4.2 in my cj-7. during the researching process I was like you and really didn't know if I really wanted to attempt it or just by the kit, but after completeing it I don't know why I didn't do it years ago!!!! If you use the binder thread Bill basically walks you through every step but he does have several variations for the distributer. I did mine three years ago and it has been trouble free since. I highly recomend it. one other advantage the junkyard unit gives you is by the time you get it inistalled you know every wire in the system so future trouble shooting is much easier. And like someone stated eairler if you can take a complete system off of one vehicle you will be better off. good luck.
 
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