TBI systems vs DIY vs each other

[coiler]

Get the eddy mpfi system and never see tail lights again even in a mild built 401. Simple to setup runs like a new efi car response is insane QT didn't like it after new tranny was installed oh well next weekends project.

[Hutti]

Next time I go DIY

I bought a Howell mostly because I liked the fact of it having a custom wriring harness and all the parts are new and tested. I did have my share of problems with the system but that was mostly because of a bum engine. The quality of the kit was great but left some things out that I would like to have next time.

Now that i had to figure out how to burn my own chips (thanks Bill and Binderbulleting!) I realize what limitations you have with that type of a packaged system. Now I am adding N/P switch wires, AC/Fan on, and speeds sensors to fine tune. Additioanlly, I will have to gut my Dizzy to add spark control.

Chaning the computer to the chips is really no big deal. I had never done before but completed it successfully in a little over an hour. Let me tell you, burning your own chip makes ALL the difference.
Check out Binderbulletin.org and moates.net

[Chris in Idaho]

You DIY guys, where do you get your adapter plates for the 258? If anybody needs one please let me know.

[86_J10]

It looks like almost everybody is using TBI, I did come across somthing interisting the other day, I am working on a MPFI system for a Comanche that I plan to run at Bonneville. I was thinking of using a Megasquirt, but at the moment it does not support sequential spark or fuel. So i was looking at some of the aftermarket ECU systems, and finally seteled on using Haltech. But in working with them, I fount out that they have a computer that replaces the GM TBI computer. the model number is E6GMX. The advantage is that you don't have to screw around with eproms, and the computer will actually tell you whats going on. Here is a link to the info http://www.haltech.com/index.php?option=com_content&view=article&id=53&It emid=49 So if you already have a GM TBI system or even a wiring harness, you can plug this computer in and get a fully tunable system. It lists for about $890.00 but I am a dealer, so if you PM me i can probably help you out on the price.

[FSJ Guy]

Ouch. That's pretty pricey. For $329, you can get a flash conversion setup and programmer for the GM ECM from Moates.

[86_J10]

True enough, but the Haltech will also give you real time data and can work with a wideband O2 sensor. I think the Megasquirt is the best deal, I am working on a harness to make it plug and play with the GM TBI. $400 for the CPU or a lot less if you wnat to put it together yourself.

[Joe Guilbeau]

Originally Posted by PlasticBoob

The only downfall is that you have to know what you're doing, and it takes a long time to understand and tune (plus soldering together the ECM takes time if you opt to go that route).

This is too funny!

Lord forbid that we actually know what we are doing...doh!

[PlasticBoob]

Originally Posted by FSJ Guy

Ouch. That's pretty pricey. For $329, you can get a flash conversion setup and programmer for the GM ECM from Moates.

My MegaSquirt II came to a grand total of $262 (including shipping) for the ECU. Add $45 for the test stimulator (simulates an engine) if you are unsure of your soldering skills.


Parts are mostly standard, automotive-grade (high temp) off-the-shelf electronics.

The code is open-source.

24MHz, 16-bit processor (versus the GM 8Mhz, 8-bit proc) for fuel control up to 1 microsecond

supports single or dual MAP sensors for real-time barometric correction (SWEET!)

supports single or dual narrowband or wideband O2 sensors

direct timing control (you do NOT need any HEI module to trigger the ECU, so reliability is increased) via a variable reluctor, hall sensor, optical trigger, or even POINTS. Yes, POINTS.

...and it can be reused on just about any engine (not just TBI Chevy/AMC V8s) with little if any circuitry mods. All this with the ability to tune the car directly from your laptop while the engine is running, or set it to "autotune" and just drive around and let the wide-band oxygen sensor do the work. $262.

Originally Posted by Joe Guilbeau

This is too funny!

Lord forbid that we actually know what we are doing...doh!

Just a little e-sarcasm there! But like I've said before, I totally understand that some people don't want to mess around with tuning EFI - they just want something they can bolt on and be done with, so I understand why those people might not want to go the DIY route. However, from what I have read, I get the feeling that no matter which way you go, you'll end up having to learn a thing or two about EFI.

[FSJ Guy]

Wow! A dead thread revival if I ever saw one!

[Geminiroq]

Originally Posted by PlasticBoob

My MegaSquirt II came to a grand total of $262 (including shipping) for the ECU. Add $45 for the test stimulator (simulates an engine) if you are unsure of your soldering skills.


Parts are mostly standard, automotive-grade (high temp) off-the-shelf electronics.

The code is open-source.

24MHz, 16-bit processor (versus the GM 8Mhz, 8-bit proc) for fuel control up to 1 microsecond

supports single or dual MAP sensors for real-time barometric correction (SWEET!)

supports single or dual narrowband or wideband O2 sensors

direct timing control (you do NOT need any HEI module to trigger the ECU, so reliability is increased) via a variable reluctor, hall sensor, optical trigger, or even POINTS. Yes, POINTS.

...and it can be reused on just about any engine (not just TBI Chevy/AMC V8s) with little if any circuitry mods. All this with the ability to tune the car directly from your laptop while the engine is running, or set it to "autotune" and just drive around and let the wide-band oxygen sensor do the work. $262.


Just a little e-sarcasm there! But like I've said before, I totally understand that some people don't want to mess around with tuning EFI - they just want something they can bolt on and be done with, so I understand why those people might not want to go the DIY route. However, from what I have read, I get the feeling that no matter which way you go, you'll end up having to learn a thing or two about EFI.

Sounds like a sweet deal....I am in So. Cal too!

Are you able to pass smog with this setup and did you source all your parts except the megasquirt?

This sounds like something I can do and I want to learn as much as possible about this. system.

Thank you...

[MistWolf]

Good one to resurrect you ask me

[PlasticBoob]

Originally Posted by Geminiroq

Sounds like a sweet deal....I am in So. Cal too!

Are you able to pass smog with this setup and did you source all your parts except the megasquirt?

This sounds like something I can do and I want to learn as much as possible about this. system.

Thank you...

Well since my Jeep is a '74, I don't have to smog it - but I plan on taking it to a friend once I get it fine-tuned, just for kicks.

My parts are just the TBI unit from a Chevy 454, Holley adapter, standard GM IAT and CLT sensors, Ford E-150 in-line fuel pump, and an Innovate LC-1 oxygen sensor. Oh yeah, and a custom cold-air-intake I'm working on using Spectre's surprisingly high-quality parts - I'll get pics of it soon.

One other thing - on my Jeep at least, I'm pretty sure I needed a body lift to get the TBI unit to clear, but you may be able to get away without one if you have standard motor mounts (I do not).


MegaSquirt will pass the actual emissions test with flying colors, but it will fail the BS test (visuals and all that) since this RIDICULOUS STATE requires you have the original smog equipment and carburetor on your vehicle. Your best bet is to get a CARB-approved EFI kit. I don't know the exact rigmarole you have to go through, but maybe you can somehow get a Holley EFI CARB sticker that would fool the smog guys into thinking the DIY is a Holley system.

[3rdelement]

So Ive been throwing around the idea of going EFI also. for reliability, and the fact i have large variations in altitude living in colorado. I have experience tuning newer import cars with stand alone fuel management systems like the haltech. I have someone that is experienced in working on v8's. Is a junkyard diy something I should be able to tackle successfully?
Also the parts listed above.. is there anything else i would need?

TBI unit from a Chevy 454
Holley adapter(part number?)
standard GM IAT and CLT sensors
Ford E-150 in-line fuel pump
Innovate LC-1 oxygen sensor
custom wired harness
what control unit?(ecu)

[jaber]

Originally Posted by 3rdelement

what control unit?(ecu)

The GM unit ending in 7747.

[3rdelement]

thanks! could i just pull the ecu off the truck i find the tbi on? (as long as it has the 7747 code)

[shackwrrr]

You could follow the link in my sig. That is the exact thing I am doing to mine but with megasquirt. 7747 computer is the easy way out if you ask me and I always like doing stuff the hard way.

[jaber]

Originally Posted by 3rdelement

thanks! could i just pull the ecu off the truck i find the tbi on? (as long as it has the 7747 code)

Yes.

[3rdelement]

thanks for the help guys. Im trying to ask as few questions as i can since i am new to this, and do as much research on my own.

[86_J10]

Haltech has a new model called the Sprint 500, you should be able to find it for $800-900 and it comes with a wiring harness. It is probably allot more powerful than a megasquirt. The injector driver that comes with the Haltech will not handle low impedence injectors, you would have to add somthing like this http://www.jbperf.com/p&h_board/v2_0.html

The haltech would support wasted spark, but you would have to add a 36-1 trigger wheel and use somthing like the LS6 coils.

Indy Cylinder heads makes a intake that will take 8 injectors if you wanted to go with port injection, no idea on price.

[FSJ Guy]

Click on my sig file link and read up on the TBI pages. FSJ specific information and general info links are provided.

Short version: I have a modified turnkey system that now has spark (timing) control. Everything works like GM intended it to except I don't use a knock sensor.

MS is definitely getting more support now, but it DEFINITELY is not a plug n play type of system. But if you really want to play with it, it will do things the GM TBI engineers never even dreamed of!

If I had time, I'd look into a MS system. But I'd rather be