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Would it be possible to use the Caddy 4.9 liter Crank Trigger in the distributer and would it work with the LT1 ECM? The reason I was asking is I am interested in doing an SFI setup on my motor. I was going to use the 730 and run batch fire but It seems like the LT1 ECM would be more efficient and it has growing support for people using them in other applications. My question is can you adapt the crank trigger to use it in an HEI distributer? I have been hearing about it but never have heard about anyone actually converting it over? Also would this trigger work right with the LT1 ECM so you dont need the optispark if you are using this in a different motor? - Justin
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I'm also looking into this conversion. However, I'm approaching it from a standpoint of transplanting opti-spark guts into the HEI. I found a site that shows what's inside the optispark. I can kind of envision how it would go, I just have yet to go do it.
I checked out that site it has a lot of good info. If you end up adapting the optispark guts into the distributer housing what do you use to trigger the ignition coil packs? Sorry if that sounded dumb i've never messed with the LT1 system before. Do you have any other info on it? Thanks - Justin
Originally posted by 730tpi If you end up adapting the optispark guts into the distributer housing what do you use to trigger the ignition coil packs? Sorry if that sounded dumb i've never messed with the LT1 system before. Do you have any other info on it? Thanks - Justin
LT1 doesn't have coil packs, the optispark distributor is a distributor just mounted on the timing cover. As for the coil you would use a standard LT1 coil and a LT1 ignition module.
EFI332, VEMS, & Ultra Mega Squirt will do individual cyl trim IIRC.
Bruce keeps mentioning the 2240 ECM as a good candidate for SEFI etc.
I have a pic of the opti wheel mounted in a HEI. But it has a logo in it so I don't want to post it.
I found a link a while back where it showed someone working on the opti hei swap but didn't book mark it correctly.
I ended up with the above link instead.
I haven't found a source for individual opti parts- sensor or wheel. What are your plans for that?
Is it me or is that a Mitisubishi symbol on that opti sensor?
__________________ 89 GTA 355 A4 4 sale
69 rS 383 A3 4 sale
68 SS 468 M4 4 sale
My plans for it were to run an SFI motor with GM factory parts since most aftermarket systems are pretty expensive. The motor that it is going in is bigger than a 350 so another thing I might be nervous about is the MAF sensor. Hey Z69, What system is the 2240 ECM from? Thanks - Justin
I don't recall what the 2240 comes in exactly.
It was a one year only caddy app IIRC.
Do a search on 2240 w/ Grumpy screen name.
I was thinking, there is a lotus bin with a hac that was SEFI I think. Not sure that would be any easier to find though.
Don't recall where I found the hac.
Originally posted by Z69 I don't recall what the 2240 comes in exactly.
It was a one year only caddy app IIRC.
Do a search on 2240 w/ Grumpy screen name.
I was thinking, there is a lotus bin with a hac that was SEFI I think. Not sure that would be any easier to find though.
Don't recall where I found the hac.
Take the 8D, modify it to program the SEFI chip (in the 2240), and double the pulse widths.
Then do what everyone's been talking about, and edit the 8D to be race code. Cut out the routines that waste processor time, and then think out what it would take to really make the code performance car friendly.
If you guys really could get organized, and work as a team, you've been given what combo to use, and what to do, you could have an ecm and code light years ahead of most of the aftermarket ecms.
The 77-2240 is a 1990 Cadillac Seville 4.9L ECM. It's the first year for SEFI in these cars.
Hmmm... this Cadillac ECM appears to have the same mechanical construction as the 7730. Seems that a little repinning and rewiring of my existing harness and it'll plug right in. Need to get hold of the wiring schematic...
Been doing a little more research... it also appears that this caddy uses a large cap HEI distributor.
Still trying to figure out though how it get's the info for the sequential injector firing.
Is this ECM supported by tunercat and tunerpro? Thats a pretty good idea. I am going to have to see if I can find this ECM at the salvage yard. Does anyone know if this system is Map or MAF? Thanks - Justin
PRetty sure it's MAP. I've been compiling some part numbers from the AC Delco site...
All distributor components are Corvette HEI except the hall effect switch.
Various sensors (I think these are the correct ones)
MAT 25036571
MAP 213-1561
O2 AFS23
TPS 141-440
CTS 213-928
The Caddy TPS is not mechanicall interchangeable with the TPI TPS. DOn't know if the electrical output is the same...
Not sure about the electrical outputs of the other sensors either... It'd be nice to get hold of an ECM pinout schematic for this 2240.... anyone have anything??
Are you sure thats the part number for the ECM? I am getting 16132240. I'm not sure if thats right though. Just figured I would mention it. Is the TPS the same as the LT1 TPSs? Do you have a picture you could post of it? Thanks - Justin
Are you sure thats the part number for the ECM? I am getting 16132240. I'm not sure if thats right though. Just figured I would mention it. Is the TPS the same as the LT1 TPSs? Do you have a picture you could post of it? Thanks - Justin
Originally posted by 89 Iroc Z
[b]Here is the wire diagram for the dizzy in a 91 deville, should use the same distributor and optical sensor setup as the 90.
YES!!! I'll be pouring over this for the next few days!!!
Originally posted by Grumpy Take the 8D, modify it to program the SEFI chip (in the 2240), and double the pulse widths.
Then do what everyone's been talking about, and edit the 8D to be race code. Cut out the routines that waste processor time, and then think out what it would take to really make the code performance car friendly.
If you guys really could get organized, and work as a team, you've been given what combo to use, and what to do, you could have an ecm and code light years ahead of most of the aftermarket ecms.
And find or hac a 2240 bin......
Insufficient interest best I can tell.
We didn't even get much on the 8D wish list.
I've kind've given up on others helping anyway.
And most of the people that know something seem to end up running boost and some other code......
I figure JP and me have another year of 8D tinkering to do
and then I might move on to something else.
Originally posted by Z69 EFI332, VEMS, & Ultra Mega Squirt will do individual cyl trim IIRC.
I don't think the Ultra MegaSquirt does individual cyl trim yet. The best it can do is bank fire. I was thinking about going to it due to big fuel injectors. You can do alternate skipped bank firing at idle so that the PWs are doubled. That is, squirt the odd cyls on an inject event, then squirt evens on the next. That way the small PWs will be decent sized. It can use a WBO2 as *the* sole O2 sensor. It is MAP and will do boost. Not trying to advertise here. I just like what they are doing with it. I haven't tried one yet.
It is good if you like doing source code because it is all written in C and the source is freely available. Bad part is that you lose LIMP mode and need to carry a GM ECM as a form of LIMP home. I don't know why but I am still stuck on using GM ECMs. I must like doing things the hard way.
I have never seen any HP numbers showing how much average HP (not peak) is gained by going from batch to sequential. Anyone have figures that they could post? From my calcs I only see SEFI being better at below approx. 2000rpms. I don't understand from a performance point of view how much better it can be. Obviously, my SEFI knowledge is rather small. Not much out there to read out there with real numbers showing the difference.
An N* ignition setup would solve that problem.
Or a vortec crank trigger and modded dist to get the correct timing signals. I'd suspect the MS site has the hall sensor p/n and info for a DIY approach.
VEMS looks to be a nice setup on the hardware side.
But a little pricey and an overseas purchase.....
If I was a little less curious and had a slightly fatter wallet.....
OR already new C or whatever they use.
The stock 2240 iac and tps need to match the tpi electrical specs. Which they more than likely do. So that part would be a non issue.
The mask and ads will be the big hold ups if you don't swap to alternate code. And most of that work would be in the 2240 hac to get all the I/O figured.
I may have to look around for one of these ecms to add to the pile by the back burner.
Originally posted by Z69 And find or hac a 2240 bin......
Insufficient interest best I can tell.
Man, I bet if a process was developed to easily switch a TPI from batch to sequential, the interest would go through the roof.
I guess one of my big questions is whether the 2240 has individual fuel trim like the LT1's. Or rather is it just a "batch" fuel trim but the firing is timed to the engine firing order?
Caddy cam sensored distributors are everywhere, repeat everywhere. Easier to convert to the cam sensor in cap than it would be to use the actual opti wheel in the cap
(would only be 8 cyl for sequential vs 360 degree for locating crank, but would it matter if we are not doing individual cyl trim for fuel and spark) Someone alot smarter than me would have to answer about doing actual code for cylinder trim and the like?
I wasnt able to locate a 2240 ecm however? Is there any other number it may be under?
I notived Ultim8Z pics of the ecm so I will further my search and maybe get back again this week/weekend.
Another thing I noticed on these ecms is they use the cam sensor only and no type of crank sensor, am I correct here? Couldnt see any evidience of such poking thru all the Cads at the yard.
Now going from batch to sequential, is like Bruce said earlier, double the firing time since your going from batch 2x to sequential once per hole. I understand the why, not quite clear on the software end of actually executing it.
Another thing I thought of, some rumor(maybe truth) of these ecms have issues in the day? Is it true number 1 and if it is was it a software or a hardware issue?
later
Jeremy
Last edited by 3.8TransAM; 11-17-2005 at 09:51 AM.
Originally posted by 89 Iroc Z Here is the wire diagram for the dizzy in a 91 deville, should use the same distributor and optical sensor setup as the 90.
That TPS looks exactly like a 95' LT1.
I just put one like that on my 52 mm TB for my HSR.
I'm thinking the IAC is also the same from that era. Have to confirm what it looks like tonight.
Run different outputs with relays to operate the IAC if needed. Electrically there are means to do it.
As I understand the system (or not) the SEFI needs to be aware of which cylinder needs to be fired/injected.
A cam signal to correlate with the crank position to determine this.
I like the idea of the cam sensor being in the dizzy. Should be kindo easy to get a signal from some of the buildups out there.
Couldn't you just get something to indicate #1 and then count the PPR on the Opti sensor to fire the module from the ECM and have the timing there for the fueling? It does involve a bunch of code work but only to interpet the hardware and get the sequence to function at speed. Integrating the hardware counters and timers will be the difficult part, at least it appears that way to my simple mind. Link the trigger points to the fueling and spark code that already exists, just insert some control before the output calculation completes.
Seems do-able unless I'm missing something
Using the above ECM or not, looks like the same amount of development and research.
Originally posted by Grumpy Well sh1t.....
That IAC kills it.......
Oh well, it was to good to be true.
Not to mention that you have to add 6 more wires just to control the fuel injectors. Way too much work.....that kills it for me.
Changing the IAC is a nothing thing. The picture of the IAC looks LT1 and 1990's V6 ish. Both are the same, some have slotted holes and some don't. The V6s are slotted. LT1 is not.
The IAC in the picture can't be wired like the IAC in the schematic. Is the schematic wrong or the IAC picture wrong?
The biggest difficulty I see is installing cam position sensor and getting the position of it right with respect to where the code thinks it should be. Once you get beyond that, then it is code dissasembly time. That isn't that bad because there are some good hacks out there to learn from and most of the BINS have the same "looking" functions just located at different places.
The Cad distribs look like a large cap HEI with an extra cam sensor in it on its own little pedestal.(someone have a picture for those who havent seen it?)
Measure that out and we have a way to mount ours, least the how far away and where in relation to the point of the reluctor.
Packaging it in a small cap HEI could be fun however.
Addint the additional wiring wouldnt not be to bad. I'll see if my friend has an old hacked up harness(not sure if it survives or not) and find out where the splice is for the commong injector ground.
Originally posted by junkcltr . . .The IAC in the picture can't be wired like the IAC in the schematic. Is the schematic wrong or the IAC picture wrong? . .
The Caddy's use a motor that pushes open the throttle blades. It isn't a stepper like the IAC, it is a reversable motor that drives a rod. A linear actuator could be the proper term.
The ECM has an H bridge driver chip. Not a stepper driver chip.
Other then that the '2240 ECM is chock full of goodies, 8 injector drivers, lots of digital I/O, and tons of RAM. The ECM itself controls the trans (it is a PCM), cruise control, and a bunch of other stuff.
The stock '2240 ECM uses a '512kb chip, which is quite full. There are blank areas that are decoded for the hardware.
The ECM controls alot of other stuff then just the engine and transmission. It controls, the A/C, curse control, climate control, heated winshield, ride control (body control module), air supsension control, and alot more. This ecm also has VATS.
I can see why it uses a 512k chip now there is a lot of bulk in the code that could be taken out and you would have a ton of I/O's for doing lots of preformance related stuff.
It would be easier to adapt an alternate code than do all that work on a 512k chip. Would still need to do a little hacing on the stock bin. But getting that mask up to the level of the $58 and $8D would take a huge amount of man hrs.
Some one needs to post a bin so it can be seen what we're even up against. Also would need to get a pcb knowledgeable person to map out the I/O.
One other detail I hadn't noticed previously, is that the reluctor on the caddy distributor is only a 7-tooth, not the usual 8-tooth. The flat spot where the missing tooth would be enables the reluctor to fit past the cam sensor, when installing the distributor shaft.
Last edited by Dave_Jones; 11-18-2005 at 02:26 AM.
Originally posted by 89 Iroc Z The ECM controls alot of other stuff then just the engine and transmission. It controls, the A/C, curse control, climate control, heated winshield, ride control (body control module), air supsension control, and alot more. This ecm also has VATS.
I think this is required when the mother in-law is along for the ride.
I'm in if we can get something going. BTW I was in the yards a few weeks back looking but not too much in detail on the caddys and ran across some of the V6 cars that had similiar looking ECM's. I believe they were the 3800 series motors. The puter I believe ended in 92. These motors use 3 sets of coil packs. I couldn't see how they were being fired though. Either way I like the idea of using the caddy to run an opti or even the caddy code for that fact. SEFI with converted bolt ins on a GenI motor and I am there.
Count me in to. I think 2 of the hardest parts are going to be adapting the IAC to work with the TPI motors and working with the code of this ECM. Other than that alot of the other sensors are bolt on. I wonder if the 90-92 speed density knock circuit is the same as the knock circuit on the caddy ecm. - Justin
Originally posted by ULTM8Z Does anyone have the bin file for the Caddy? I e-mailed Tunercat about it and he's interested in it, but needs to see the bin.
Man, it'd be fantastic to have this definition file available in Tunercat.
I'll be pouring over this for the next few days!!! 
