Going to the darkside; 258 TBI

[Grand_Wag_85]

Here goes nothing, going to fuel inject my 258 J10. To put it lightly I have no clue what I'm getting into. I've done a TON of reading and the more I read into it all the more lost I get. Only thing I've really figured out is that I can make the V8 TBI stuff work on my 258.

I've got a complete TBI setup(minus atleast the fuel pump and O2 sensor).


All I really know is that it's from an '88 Chevy with a V8, Firebird/Camaro maybe?

Is this the good ECM?


Based on what I've got right now how much stuff can I eliminate? Anybody have a complete wiring diagram?

I've got an HEI ignition so I'd like to tie that into the system by converting it over to the 7 pin module.

Can the ECM and diagnostic port live under the hood or does it have to live under the dash?

[Bill usn-1]

AMTT is a 1988 5.0 auto from a C1-1500 truck.
The 1227747 ecm is a good one to use.

Everything you need to convert that system is listed in the injection forum FAQs on binderplanet.com.
http://www.binderplanet.com/forums/show ... hp?t=47254

The 7747 is not water proof so the best place is in the glove box or under the dash. If you do a ot of water crossings then mount it in a tupper ware box with a lid and seal up the cable.

You can convert the large cap HEI for the 7pin or replace with the motorcraft distr and munt the 8 pin external.

[jaber]

I converted the stock Caddy HEI to run off an 8 PIN mod. Works great.

Overwhelming, yes, but just start with the basics and take it one step at a time.
Thin wire harness, figure out where its going to live, then do fuel, then spark, then sensors. Next thing you know, you'll be firing it up...

[Grand_Wag_85]

Thanks guys!

Bill-
I've run thru that thread many times and I'm still confused lol.

Jeff-
Sounds like a plan and hopefully fire it up sooner rather than later.

[Bill usn-1]

Bill-
I've run thru that thread many times and I'm still confused lol.

There are many threads in the FAQs there broken down into small parts of the system like the what parts do you need, then what wires do you need, then distr conversion then there's the step by step install thread with pics, then once it's all installed there is the ISPs-initial setup procedures, then once it's running there are the data logging and even the basic tuning threads.

When you hit something you don't understand then you simply ask a question.

it starts to make sense by about the 3rd time you read through it while looking at all the parts you have gathered.
Just about every guy on here that has the DIY GM TBI installed, used those threads and they all got theirs running.

[Cecil14]

I guess I'll ask the obvious question...why? Why not use the stock 4.0 MPFI? It'll perform quite a bit better than any TBI will. Plus it's plug any play, more or less. You can swap all the parts directly off a 4.0L and just drive it. Only thing you have to provide outside is a fuel pump.


aa

[carnuck]

I'd like to point out that it's '91 to '95 that you want all the parts from.

[mineral co]

Grand_Wag_85, I'm right there with you! I'm planning to do my '84 GW, and I've read until my head hurt on many different days. I finally start to get it straight in my head what ECM I want, only to find out there are variations in each type of ECM! The people that know what they're talking about are frequently conversing with other people that know what they're talking about, and I can't get a damn thing from it.

I think I have it in my head well enough now to get started, but it sure wasn't easy! Maybe we'll do this in parallel.

[Bill usn-1]

No need to be confused.
All you need to do is ask a question.
I see lots of guys just lurking over on the BP and never ask a question. So I assume I have completely explained everything in detail and there are no questions.

You can ask here also but I don't get over here as often to give quick responses.

[Grand_Wag_85]

Couple questions for today.

What happens if I DON'T run the VSS, will the Sun implode? I see the inline kits out there, is there enough room behind the instrument cluster to plug this in or will I need to get another short cable and do it that way? Anything in the junkyard that I could snatch this style of VSS from?


For the 02 sensor my Jeep has the factory manifold meant for the BBD madness with the 02 sensor. Can I just put mine where the factory one was? Also, will I need a cat?

Last but not least I need to be able to tune it. From the reading I've done it sounds like I need the Eprom chip? What equipment do I need to connect the laptop to the TBI stuff?

[Grand_Wag_85]

I guess I'll ask the obvious question...why? Why not use the stock 4.0 MPFI? It'll perform quite a bit better than any TBI will. Plus it's plug any play, more or less. You can swap all the parts directly off a 4.0L and just drive it. Only thing you have to provide outside is a fuel pump.


aa

I've given it a LOT of thought and I'm collecting the parts to do it on my AMC Eagle. With the FSJ you need hydroboost so the 4.0 intake manifold will clear everything. Also I don't really feel like swapping cylinder heads at the moment and the TBI stuff I've got in the photos was all free LOL. The MPFI can be made to run with the stock 258 head but from what I've heard it won't be right.

[Bill usn-1]

Couple questions for today.

What happens if I DON'T run the VSS, will the Sun implode? I see the inline kits out there, is there enough room behind the instrument cluster to plug this in or will I need to get another short cable and do it that way? Anything in the junkyard that I could snatch this style of VSS from?

For the 02 sensor my Jeep has the factory manifold meant for the BBD madness with the 02 sensor. Can I just put mine where the factory one was? Also, will I need a cat?

Last but not least I need to be able to tune it. From the reading I've done it sounds like I need the Eprom chip? What equipment do I need to connect the laptop to the TBI stuff?

At the risk of sounding repetitive...it's all covered in the FAQs on the BP.
A couple of the latest threads there are specific to the 258 in jeeps!

But to recap...
Yes the sun will explode and the EMP will wipe out everything electrical so it just won't matter anymore.

But "when" not "if" you install a properly tuned chip for your system/engine, all will be right in the world.
For street driving it is best to run the VSS.
It goes right on the trans/transfer case. You unscrew the cable, install the VSS and screw the cable back on it.
Connect the 2 wires.
I also carry the JTR VSS for $75.

Yes you can use the same O2 sensor location as your feedback system.
I dod not know of any factory VSS that will correctly install and work with the 2 pulse signal the ECM uses. GM was a 4 pulse and was sent to a DRAC signal converter and then the 2 pulse signal went to the ECM.

You either have to buy the equip and learn to data log and tune or you just buy a tune made for your engine/system.
I charge a flat $100 for a tune. You just have to make sure your system is working properly and you can log data.
If you can buy the equip and learn how cheaper than that...then I say do it.
Or if you just like to learn like I did when I started out.
If your not going to be doing this a lot then not much need to buy everything.

[243]

I don't think you will regret it one bit, I made my own adapter, modified my harness and rebuilt the TB over a period of two years. I broke in my motor with an MC2100 and then started the install referring back to Bill's FAQ throughout the installation. Follow the FAQ, do the pre-function tests and double check all your wiring and you will be fine.

I had a number of issues, mostly wiring and I can't think of a single problem I had that was not covered in the FAQ or the thousands of TBI threads.

Bill, I still have the chip retainer I owe your for the CJ, it's sitting in the console of my truck. I received a complete system via UPS today and plan to install it on the Cherokee in the next few months, I will send you two retainers when I order a chip for the 360.

[FSJ Guy]

You want the 2PRS, IIRC, from JTR. Send them your $75 and they will send it out to you ASAP.

www.Moates.net will have your data logging stuff. For the 7747 ECM, you will want the G2 Adapter or any of its variants (You can get a bin switcher for it, too.)

The AutoProm will work to allow live updating and data logging all in one if you like. A less expensive option is an ALDL cable and the Burn2 burner. You will need at least one 27SF512 chip to burn your files. I'd order at least three because if you're like me, you'll burn one of them up when you accidentally insert it backwards. :- p

I don't recommend mail order tuning. It takes too long. You have to log, send data, wait for a chip in the mail.... Lather, rinse, repeat. I've burned over 10 different bins in a single day playing around with things.

Don't forget TunerPro! It's freeware, but well worth the $40 "registration" to thank the author of this software.

[243]

Ethan,

That may be true with some tuners, but I datalogged and uploaded my files to BP, Bill reviewed the data and mailed my chip in a five days at the most. I ran the chip, logged the data and Bill saw no reason to change it. I do want to play with the tune but to get off the ground and running, it was 100.00 well spent.

[Grand_Wag_85]

Thanks Ethan.

One last question.

I'm planning on hooking the ignition into the TBI as well via large cap HEI. After the mods to the distributor what angle do I set the distributor at?

[FSJ Guy]

I'm not familiar with the HEI, but you will need to find a way to lock out the centrifugal advance and lock or remove the vacuum advance.

On the OE distributors, I simply lock out the mechanical advance with a small weld and leave the vac advance intact, but just don't hook the hose to any vacuum. I have not had rotor phasing issues this way. Hopefully, the HEI will be similar. Someone who actually HAS an HEI and has converted it will hopefully chime in.

[Grand_Wag_85]

I'm not familiar with the HEI, but you will need to find a way to lock out the centrifugal advance and lock or remove the vacuum advance.

On the OE distributors, I simply lock out the mechanical advance with a small weld and leave the vac advance intact, but just don't hook the hose to any vacuum. I have not had rotor phasing issues this way. Hopefully, the HEI will be similar. Someone who actually HAS an HEI and has converted it will hopefully chime in.

I understand all that, that's the easy part :p Something about a harness from an 80's caddy with the large cap HEI and swap a 7 pin module in along with locking out the advances.

What I'm trying to figure out is after that's done is there a certain angle the distributor needs to be pointed or just leave it where it was and the computer figures it out?

[FSJ Guy]

Angle?? Time it so that it's at the static timing that you set in your bin. Chevy static timing is zero degrees. I like to set it at 10 degrees myself, but that's for the AMC 360. The I6 may want something different.

[Grand_Wag_85]

Angle?? Time it so that it's at the static timing that you set in your bin. Chevy static timing is zero degrees. I like to set it at 10 degrees myself, but that's for the AMC 360. The I6 may want something different.

Yup, timing...that's what I meant. Late night brain fart.