84----ecm who knows
Thread Starter
Racer
Joined: Oct 2011
Posts: 312
Likes: 0
From: state of insanity
84----ecm who knows
WHO KNOWS ABOUT ECM'S? I HAVE BUILT AND RESTORED CARS,GROUND UP FRAME OFF RESTORATIONS FOR 40 YEARS.BUT NEVER THE NEW STUFF.I HAVE A 84 STOCK. I HAVE READ THERE ARE VERY FEW MODS YOU CAN DO TO THE ENGINE DUE TO THE ECM.I GUESS 84 ECM'S ARN'T VERY SMART.I WOULD REALLY LIKE TO PUT A DIFF. MOTOR UNDER THE STOCK INTAKE AND INJECTORS. SETTING IN THE SHOP I HAVE SEVERAL ALREADY BUILT.FROM 383'S TO 421 INCH SMALL BLOCKS. ALL ARE BUILT PRETTY STOUT.HEADS,CAMS, ROLLERS, FLAT ,TO HYDRALIC ROLLER MOTORS.I READ AND FOUND 2 INCH THROTTLE BODY BASES TO INCREASE THE CFM.PRESSURE REGS. ETC. MY QUESTION IS, IS THERE, WHATS AVAILABLE FOR ECM TO HANDLE MODIFICATION,S. OR AM I STUCK WITH 180 H.P.
I WANT TO KEEP THE STOCK MOTOR TO PUT BACK IN IN THE FUTURE,SO I DON'T WANT TO MOD.THE ORIGINAL. ANY INPUT APPRECIATED. HAVE ALREADY BUILT THE TRANS/WITH SHIFT KIT TO HANDLE 600 PLUS HORSE SO THAT WON'T BE A CONCERN.
I WOULD LOVE TO GIVE THE NEW VETTS A RUN FOR THERE MONEY. EVERYBODY LIKES OUR VETT. BUT THE FIRST THING THEY SAY IS HOW SLOW THEY ARE.HENCE I WANT TO KEEP THE STOCK SLEEPER LOOK UNDER THE HOOD, OTHER WISE I WOULD JUST DROPIN THE 421 WITH THE 1050 DOMINATOR THAT IS ON TOP. THIS MOTOR RAN 8;40'S ON NITROUS IN A 2300 LB TUBE CHASSIS CAR.
I WANT TO KEEP THE STOCK MOTOR TO PUT BACK IN IN THE FUTURE,SO I DON'T WANT TO MOD.THE ORIGINAL. ANY INPUT APPRECIATED. HAVE ALREADY BUILT THE TRANS/WITH SHIFT KIT TO HANDLE 600 PLUS HORSE SO THAT WON'T BE A CONCERN.I WOULD LOVE TO GIVE THE NEW VETTS A RUN FOR THERE MONEY. EVERYBODY LIKES OUR VETT. BUT THE FIRST THING THEY SAY IS HOW SLOW THEY ARE.HENCE I WANT TO KEEP THE STOCK SLEEPER LOOK UNDER THE HOOD, OTHER WISE I WOULD JUST DROPIN THE 421 WITH THE 1050 DOMINATOR THAT IS ON TOP. THIS MOTOR RAN 8;40'S ON NITROUS IN A 2300 LB TUBE CHASSIS CAR.
Last edited by mtnmanut; Nov 9, 2011 at 12:51 PM.
Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
take apart your old crossfire injection,put a new base manifold for TBI application and buy a brand new Holley Avenger tbi injection,it comes with a simple device for tuning and saving calibration .Just set some specs into your Avenger like cubic inches and launch the self learning function just driving around your car...
http://www.holley.com/types/Avenger%...%20Systems.asp
http://youtu.be/Pc-BDt1dj9U
http://www.holley.com/types/Avenger%...%20Systems.asp
http://youtu.be/Pc-BDt1dj9U
Tech Contributor
Joined: Jun 2004
Posts: 20,870
Likes: 961
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
The '84 ECM isn't as bad as a lot of people say, but it does have limitations that later GM/aftermarket controllers don't have.
I've run my stock '84 ECM (with modified calibration PROM contents) for several years with the current turbocharged 355 engine, and had no problems. However, I'm looking to bump up the boost a bit more in the future, and there's just not the flexibility with this ECM that would allow me to not have to worry about damaging the engine due to insufficient calibration/software capability. So, I'm in the process of moving to a later TBI ECM.
The stock ECM will work fine for most engines. The problem is that the calibration code that needs to be changed to work with these modified engines is not readily available (I was in the right place at the right time to get the software info I needed so I could modify the cal tables to get my engine to run well under boost).
I've run my stock '84 ECM (with modified calibration PROM contents) for several years with the current turbocharged 355 engine, and had no problems. However, I'm looking to bump up the boost a bit more in the future, and there's just not the flexibility with this ECM that would allow me to not have to worry about damaging the engine due to insufficient calibration/software capability. So, I'm in the process of moving to a later TBI ECM.
The stock ECM will work fine for most engines. The problem is that the calibration code that needs to be changed to work with these modified engines is not readily available (I was in the right place at the right time to get the software info I needed so I could modify the cal tables to get my engine to run well under boost).
Thread Starter
Racer
Joined: Oct 2011
Posts: 312
Likes: 0
From: state of insanity
Thanks 69427 i appreciate the info i did have some time today and found diff. Proms for mild and higher perf. I have contacted those manufacturers to find out how much change i can make thanks again...p.s. I noticed your location, and just to let you know,i have over 30 guns 
and three chainsaws
and three chainsaws
Tech Contributor
Joined: Jun 2004
Posts: 20,870
Likes: 961
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Thanks 69427 i appreciate the info i did have some time today and found diff. Proms for mild and higher perf. I have contacted those manufacturers to find out how much change i can make thanks again...p.s. I noticed your location, and just to let you know,i have over 30 guns and three chainsaws
and three chainsawsI'm glad to hear there's a couple sources for PROMs for an '84. I got the full software listing (years ago!) and made hundreds of changes, mostly in the VE and spark tables due to the different requirements under boost. It was a long process (run a few laps while monitoring some instrumentation, then into the pits to program a new EPROM), but the results were worth it.
Thread Starter
Racer
Joined: Oct 2011
Posts: 312
Likes: 0
From: state of insanity
so far i have found 2 sources jet performance and hypertec they both appear to make two choices stock engine upgrade and a performance chip upgrade. waiting to hear what performance upgrades can be made that there chips will handle. i imagine most of you have heard of these,but myself,being new to looking at these upgrades its al new to me.anybody have any info on these would be greatly appreciated
Racer
Joined: May 2008
Posts: 391
Likes: 1
From: Greenwich Ohio
Check out Dynamic Crossfire Solutions. They have a Ham board that will upgrade to a newer ECM.
http://www.crossfireinjection.net/catalog.htm
I want to order a Renagade intake. Waiting to see if they are going offer them again.
http://www.crossfireinjection.net/catalog.htm
I want to order a Renagade intake. Waiting to see if they are going offer them again.
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Drifting
Joined: Aug 2010
Posts: 1,704
Likes: 8
as you told,if you already have some big bottom end in the shop,there aren't any reason to keep your old crossfire/ TBI,you can go with a multipoint injection,lot of choices.you can put on the top an HSR,or a superram,or a miniram set up with a speed density EFI controller like FAST or similar...this modern ECM are smart,fast,easy to tune don't require burning and replacing chip into ecm,a better way to go....
Advanced
Joined: Oct 2011
Posts: 63
Likes: 0
From: Clear Lake Texas
If you want to keep the stock ECM: a Crane 2040 cam, Dart, Sportsman or other heads with no larger than 180cc runners 202/160 valves 1.6-1 rockers , ported and gasket matched crossfire intake, headers, and a TPI fuel pump (bolt in-no mods) wil get you deep 13's. You can run a ported CFI on a 383 with larger injectors from the 454SS ,more radical cam, etc, but will need to use a 7747 ECM with hamboard and a tune. CFI cars can and have been built to run in the 12's.
Drifting
Joined: Feb 2013
Posts: 1,462
Likes: 48
turbocharged !!
The '84 ECM isn't as bad as a lot of people say, but it does have limitations that later GM/aftermarket controllers don't have.
I've run my stock '84 ECM (with modified calibration PROM contents) for several years with the current turbocharged 355 engine, and had no problems. However, I'm looking to bump up the boost a bit more in the future, and there's just not the flexibility with this ECM that would allow me to not have to worry about damaging the engine due to insufficient calibration/software capability. So, I'm in the process of moving to a later TBI ECM.
The stock ECM will work fine for most engines. The problem is that the calibration code that needs to be changed to work with these modified engines is not readily available (I was in the right place at the right time to get the software info I needed so I could modify the cal tables to get my engine to run well under boost).
I've run my stock '84 ECM (with modified calibration PROM contents) for several years with the current turbocharged 355 engine, and had no problems. However, I'm looking to bump up the boost a bit more in the future, and there's just not the flexibility with this ECM that would allow me to not have to worry about damaging the engine due to insufficient calibration/software capability. So, I'm in the process of moving to a later TBI ECM.
The stock ECM will work fine for most engines. The problem is that the calibration code that needs to be changed to work with these modified engines is not readily available (I was in the right place at the right time to get the software info I needed so I could modify the cal tables to get my engine to run well under boost).
