edit 12/10/08: new webpage: http://northstar.7p.com/
Download the files there and you can run it yourself for almost free

Everyone, I'm proud to announce a new option for current or future northstar swappers. As I mentioned in a few threads before, there is no aftermarket computer capable of everything a GM computer can do. GM computers are built to be reliable, they have years of programming development, and best of all, have been tuned to death.

A select few of you may already know this, but for the past 10 or so months, I have been working on making the 1227730 computer compatible with the northstar. The '7730 is found in just about every FWD GM with a 3.1L, from like 89-93 or therebouts. They are cheap and plentiful. I bought mine for $40.

The past 10 months were, to be honest, hell. Setback after setback led me to believe several times that it might not be possible. The problem with doing something so revolutionary, is nobody can help you. This was extremely frustrating to say the least.

As it stands right now, it starts, runs, and drives just fine, it is 90% tuned, and I even took it to the dyno to see what it put down.



There are some minor issues, such as it running a bit rich until it warms up on a very cold day... Something I haven't had the inclination to deal with yet. Also, I haven't completely tuned the VE tables, as I found out a few weeks ago when I hit a lean spot at 1500rpm and low MAP. Nevertheless, it will work just fine on all 300hp northstars, given they have roughly the same "mods" as I have, K&N filter, dual 2.5" exhaust to dual mufflers. What's great about these GM computers, is, they've literally thought of everything. It takes care of your speedo signal so you don't have to have an $80 interface. It kicks open the throttle when you're coming to a stop so you don't stall. It does the same for when the fan kicks on. I could list a few dozen more, but I'll let you take my word for it... It's better.

So, now I've come to a crossroads. What do I do with the 10 months of work I hold in my hands? The fiero owner in me wants to release it into the public domain. The poor college student in me wants to be compensated for the time I spent on it. What I was thinking of doing, was just offering the programmed memcals, with removable eeprom, for a nominal fee, like $50 (this is assuming I can get "raw" memcals and 29C256 eeproms cheaply enough. There has been word that the 29C256 may have been discontinued or something... That could be a problem. Or, perhaps even offering plug and play computers with harnesses for $400-500. I'd have to trust any who purchase the memcal or computer system to keep them for their own use - i.e. not to later sell or distribute the program on them.

I would like to publicly acknowledge those who have contributed to the success of this project... Will Lucke especially, for convincing me that it could be done, Darth Fiero/Ryan, Ben from 60*v6, Shaun on RFT, series8217, and anyone whom I may have forgotten.

oops, almost forgot... the possibility of running boost is also there.

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Ryan - 256RWHP / 258TQ

Owner of the *only* paddle-shifted, Northstar powered fiero.

[This message has been edited by ryan.hess (edited 12-10-2008).]

Very cool accomplishment! If I were doing a N*, that would be $50 well spent. I am sure the wiring was tricky too, so hopefully you took good notes- I always start forgetting crap as soon as the project is finished...now where did that medium blue wire go?

Thanks. The hope is, that this will encourage more northstar swappers. As of today, there is only the expensive aftermarket computers, megasquirt (cheaper, but $400 ready-built), and the stock northstar computer that runs on the 275hp northstar chip.

If you wanted to put in CHRFab cams, you were stuck with an aftermarket computer or megasquirt. Then you were stuck with problems I mentioned above. Gotta buy a speedo interface, etc...

When I ask why people don't do the northstar swap, the #1 concern is the wiring. Well, a plug and play *tuneable* computer, for $400-500 with wiring harness is tough to beat.

you need to find a way to get the word out to the sand runners. i'm sure there is a large demand there.

I bet that the success of the project gives you that warm fuzzy feeling!
Reading other posts, the GM code must have been a bear to work out.
+
TG

Congrats! Glad I could be of help in there. (I'm series8217 on the other forum)

Is it possible to use that ECM to control an electronic automatic transmission like the 4T60E, 4T80E, etc?

(BTW, if you haven't check it yet the rich running cold is probably just from an improperly scaled "Open Loop AFR Vs. Coolant Temp Vs. MAP" table.)

isnt the 29c265 for the tpi 90-92 f-body/corvette sbc? There is a replacement chip that is flash, Im sure you knew that though. I will find the part # if you dont know. thanks

nevermind, I found out its the 27c265. guess that wont work. anyways. nice work!

[This message has been edited by 1fastcaddy (edited 02-09-2006).]

quote Originally posted by Steven Snyder: Congrats! Glad I could be of help in there. (I'm series8217 on the other forum) Is it possible to use that ECM to control an electronic automatic transmission like the 4T60E, 4T80E, etc? (BTW, if you haven't check it yet the rich running cold is probably just from an improperly scaled "Open Loop AFR Vs. Coolant Temp Vs. MAP" table.)

Anything is possible, actually, it is already set up to run the 4t60e, so that shouldn't be a problem. 4t65e/4t80e would be more difficult, but not impossible. You'd have to change a few values to make it shift correctly, and you would need something (external) to control the pressure on the transmission.

The open loop AFR is on my to do list... no, really. It hasn't been a big enough deal for me to change it yet, or put another way, I'm tired of burning chips. I've been working on other things, like cleaning up my wiring, and the short runner intake.

"The 'rage' among us chip programmers is the use of flash proms (called EEPROMs for Electronically Eraseable Programmable Read Only Memory). EEPROMs make our lives much easier in that a UV Eraser becomes obsolete. To program an EEPROM you simply put the chip in the programmer and program it. The programmer will both erase the chip and reprogram it. This is wonderful. There is no need for a UV Eraser, no need to wait for chips to erase, and the chips have a much longer burning life since they aren't being pounded by UV light! The magic part number here is AT29C256. It is a 32Kb chip manufactured by Atmel. This chip is a direct replacement for all 27C256 chips used in 1990-1992 TPI F-Bodies (32Kb). This does NOT mean that it cannot be used in previous year TPI vehicles. You just need to do a little 'tweaking' during the programming process. 1986-1989 TPI F-Bodies use a 27C128 chip of 16Kb. The Atmel AT29C256 chip has twice as much memory" thirdgen.org

is that the chip your talking about? thanks

[This message has been edited by 1fastcaddy (edited 02-09-2006).]

quote Originally posted by 1fastcaddy: by the way, I bought my megasquirt 1 for $240 shipped and it has msns-e to control spark. Sequential injection and C.O.P. ignition is on its way, if not in beta. not that bad. later

You mean you bought the parts for it? Not everyone can put together a circuit board.

The 29c256 you are talking about in the above post, has been discontinued or is being phased out as we speak. I cannot locate a source for them.

quote Originally posted by ryan.hess: You mean you bought the parts for it? Not everyone can put together a circuit board. The 29c256 you are talking about in the above post, has been discontinued or is being phased out as we speak. I cannot locate a source for them.

Go to www.digikey.com
Do a search for 29C256.
It shows up in several places. If you can believe what their site says, they have hundreds of them.

Question: What code did you base your build on?

Crosses fingers hoping to see "8F"

It is such a widely capable code, it can run almost any engine, and will option for boost easily

Well now.... This is something I'd be very interested in mostly because of the 4.6 sitting out in my shed. I had been bouncing around an idea of using a V-8 firebird computer and a belt driven distributer/crank trigger as an inexpensive way to install a N* but this looks like it would have far more potential. If I'm reading this right you could supply a 7730 chip that would use the caddy sensors and run it's coil/cyl ignition. Shweeet!!! How hard would it be to add boost?? Is this something that can be tweeked at a dyno facility to fit with an individual car??

I wouldn't be too worried about stringing a harness myself but I'd definitly be interested in a programmed chip. As was said before...50$ well spent.

btw BIG + for you
David

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His Fiero: 1984 2M4 Coupe

Her Fiero: 1984 2M4 Convertible

Excellent work! Sorry if you mentioned but what year N* are we able to run on you setup. ie IAC or idle plunger mtr, coil per cyl...etc

Pete

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quote Originally posted by Raydar: Go to www.digikey.com Do a search for 29C256. It shows up in several places. If you can believe what their site says, they have hundreds of them.

Any they have in stock are not the DIP-28 package.

quote Originally posted by Fierobsessed: Question: What code did you base your build on? Crosses fingers hoping to see "8F" It is such a widely capable code, it can run almost any engine, and will option for boost easily

It would (should?) be extremely easy to use the $8F code. Now that I know what to do to make it work, it would be a matter of just repeating it with the $8F.

quote Originally posted by DPWood: How hard would it be to add boost?? Is this something that can be tweeked at a dyno facility to fit with an individual car??

The $8F code I mentioned above is what you would need for boost. I don't see it being a problem. Any dyno tuners should be able to handle it with ease. What I can do is include a copy of tunerpro and a special definition that "cuts the crap out", to make it really simple. Nobody needs EGR anyways

quote Originally posted by PBJ: Excellent work! Sorry if you mentioned but what year N* are we able to run on you setup. ie IAC or idle plunger mtr, coil per cyl...etc Pete

Nope, didn't mention. It will work with 96-99 engines. It should work with 93-95 engines, because the idle motor is really nothing more than an IAC, but it may take some extra work... In the end, it may be simpler to just install a 96 intake and throttle body.

quote Originally posted by ryan.hess: Any they have in stock are not the DIP-28 package.

Ooops. Sorry about that.

Congrats on your accomplishment, though. This is going to be the answer to lots of swappers' wet dreams.
I'll bet it will work on the Shortstar (3.5 V6) too.

It won't work on the shortstar, because I believe it only came in coil-on-plug. However, I do have good news, I have a source for the time being for 29C256 chips. Moates.net has a thousand in stock, so I'd guess we have about a year's worth of chips.

So, who can I put down for one?

Ryan...You amaze me again. More stars if I could.
I'll keep you in mind for my Dad's 4.0

Bob

My PM on RFT said pretty much what you've said here... you're going to have to treat this like an open source project.

It's great that it's finally polished enough to let the "world" know about it.

You've got me interested in getting busy hacking the N* computer... after I take the GRE...

As I told you, I'll let my harness be the prototype. I'm looking into getting it done by the same company that builds harnesses for Ed Parks.

Great work, I'd be very interested. I'm just starting a 96 N* swap and am looking at making this a 400hp setup and yet as reasonable $$ wise as I can. I will probably do chrfab cams and springs.

Are there any drawbacks (besides the few minor things you're working on) between yours and the Commander 950?

When might the harnesses be available?

Edit: I even have a ecm here from when I was thinking of doing a tpi 350 build - I believe it is a 7730.

[This message has been edited by Parde_GT (edited 02-10-2006).]

Drawbacks? Almost none. Given the choice between a tuneable GM computer and an aftermarket computer, I would choose the GM computer every time. There are millions of dollars worth of development time in these computers, something aftermarket places could only dream to afford...

But, the Holley doesn't require extra parts to be tuned - you need either a chip burner ($40), which you'd have to swap chips out any time you need to make changes... This is my current setup, or, an emulator ($175?) for real time on-the-fly programming like the Holley.

Some of the really expensive $3000 aftermarket computers are pretty darn good, but that's obviously out of the reach of most of us here. I'm investigating the harnesses as we speak... I have a lead on them, really good quality - Delphi connectors and automotive environment rated wiring. I'm hoping to get one as soon as I can scrape some cash together.

If you paid for a setup today, you could have the harness and computer at your door probably in 4 weeks. That will probably drop to 1-2 weeks after I get any necessary corrections sent to the harness builder.

Will - if you can get a harness together, that will work just fine too, I just kinda realized that I have the wiring diagrams for the 7730/N*, so it might make sense for me to just take care of it. I don't know if you're planning on going to the 7730 or ?

[This message has been edited by ryan.hess (edited 02-10-2006).]

quote Originally posted by ryan.hess: Drawbacks? Almost none. Given the choice between a tuneable GM computer and an aftermarket computer, I would choose the GM computer every time. There are millions of dollars worth of development time in these computers, something aftermarket places could only dream to afford...

I might just be really, really hoping here, but, i have to ask what kinda chances are there that since you said it would work with "other" engines, that I would be able to use it on my saturn motor that's going into the fiero? Life would be great with a programable GM computer in my fiero...

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AIM= Fish100770
96 Saturn SL2 Turbo (evil SL2)

My cardomain site: cardomain.com/memberpage/702872

quote Originally posted by cooguyfish: I might just be really, really hoping here, but, i have to ask what kinda chances are there that since you said it would work with "other" engines, that I would be able to use it on my saturn motor that's going into the fiero? Life would be great with a programable GM computer in my fiero...

Sending you a PM...

Ryan; I have a 95 seville n* that I'm planing on using in one of my countach replicas, this sounds like a really hot setup. My question is will this system drive all of the 95n* emisions control devices,egr, canister purge ect, I don't have a problem with changing the intake if needed, or am I better off with the stock ecm. The reason I ask is that where I live we need to pass the IM240 insection for emissions and in this application I have to meet standards for the engine I use. thanks for your time. Joe

In theory, yes, but it will take lots of work - programming EGR tables for flow compensation, probably mounting a different EGR in place of the stock one, etc.

If you're not planning on mods, I would stick with the stock computer.

thanks. Joe

Where do I sign up on this list for a $8Fchip??

David

All it takes is an email to get the boost ball rolling...

quote Originally posted by motoracer838: Ryan; I have a 95 seville n* that I'm planing on using in one of my countach replicas, this sounds like a really hot setup. My question is will this system drive all of the 95n* emisions control devices,egr, canister purge ect, I don't have a problem with changing the intake if needed, or am I better off with the stock ecm. The reason I ask is that where I live we need to pass the IM240 insection for emissions and in this application I have to meet standards for the engine I use. thanks for your time. Joe

Man I was so tired last night that I for got to mention that turbocharging is under consideration for this project, I would guess that changes things a bit. Joe

Yeah it does... just a bit.

I think it will take a bit of custom fabrication and a lot of tweaking, but your best bet would be to use what I've got here, with the $8F code.

Thanks again,when I'm ready to move forward with this project I'll pm you. Joe

I do have another question, What did you do for Ignition? I thaught the Northstar IGN module was incompatable (for some reason) with anything but a N* ECM.

And about the Short*, well, thats easy if you have a 7X Reluctor, just use any 3.1 2.8 3.4- V6's module and coils, or double up the modules and wire the individual coils to them. Who knows, perhaps the ign module for the Short* is cross compatible? But thats kind of my first question.

quote Originally posted by Fierobsessed: I do have another question, What did you do for Ignition? I thaught the Northstar IGN module was incompatable (for some reason) with anything but a N* ECM. And about the Short*, well, thats easy if you have a 7X Reluctor, just use any 3.1 2.8 3.4- V6's module and coils, or double up the modules and wire the individual coils to them. Who knows, perhaps the ign module for the Short* is cross compatible? But thats kind of my first question.

Stock ignition. I said it's plug and play....

I don't know enough about the 3.5DOHC to say definitively whether it would work or not. I just have to assume that since it's COP, it will use some wierd crank reluctor. 18x?

[This message has been edited by ryan.hess (edited 02-12-2006).]

I just wanted to mention that after some long hours, I have more progress to tell you guys about..

When I was doing the tuning with the wideband, I had to connect the wideband o2 sensor to the MAP, TPS, and RPM "outputs" of the computer, so I could create datalogs of those with the wideband. That was quite a pain splicing into those wires, and running new ones, and obviously it's not the best approach when it comes to "neatness".

Well, I was able to use one of the ECM's unused inputs for a wideband input, so now by connecting your 0-5 volt wideband output to this pin, you can use Tunerpro RT (freeware/donationware) to log the data through the ALDL port. In otherwords, in addition to the standard stuff you see on the ALDL port, MAP, RPM, time running, error codes, BLM, etc, you can log your wideband. It's still in the "beta" phase, but it works...

So now you don't have to have a wideband that can do datalogs... Or, I guess you could even use it to signal a point in the datalog... like run a pushbutton to 5 volts, and when you drive around, push the button to mark that point in time on the datalog to review later... There's lots of things you could do with it...

I could put together a surface-mount to DIP conversion for those 29 series IC if the DIP is no longer available. Let me know if this is ever needed.

Great.

I'm watching this closely as I'm planning to do the cams and springs with a middle of the road cam grind to get the 400 HP.

I'm using a 1996 N* motor.

Please post when your ready to start selling.

Are these available yet??

I am very interested in this for the convertible.....tired of the starting problems.

LMK.

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quote Originally posted by mrfiero: Are these available yet?? I am very interested in this for the convertible.....tired of the starting problems. LMK.

Computer's ready any time you are, the wiring harness is going to take some time. What kind of starting problems are you having? Email or PM me...