Leaning on you guys

[john87442]

Ok first of all I’m sure I’m going to get some good info so thanks in advance!
My project is a 87 442. I’m installing a built 69 olds 350 but rebuilt the 200r4 to match up with it. I wanted to keep the overdrive. I’m obviously removing the air pump and not keeping the cruise control either because I want my foot in it all the time. Anyway after a conversation with someone who did a similar situation he stated he had to add a TCI kit to get it to lock up because it no longer would have the necessary equipment to recognize when to lock up the converter.
Full honesty I don’t know enough about this to know what I don’t know but I do know that this group knows so that’s why I’m reaching out to get some information and help…. Any information is appreciated and hopefully it also helps others.
Again thanks for your time on this.

 

[79 USA 1]

If you are keeping the ECM on this engine you SHOULD have no issue. I did a 355 swap in an 86 El Camino years back and kept the computer control set up minus the air injection system due to running long tube headers and never had an issue. If you are eliminating the ECM and running a non electronic carb and distributor then yes you would need the kit for converter lock up.

 

[john87442]

Ok thanks I didn’t know about that. So I need to talk to my engine builder to see what he had down for the carb and distributor I can use the ecm just wasn’t sure what I needed to do.

 

[69hurstolds]

Just a note here on the ECM or no ECM debate.

The ECM and PROM for your 442 are calibrated to be used in a stock 307. It can handle a 350, to a degree. If you start adding in lumpy cams, and monster fuel curves and all that, you're going to be disappointed. The PROM is frozen to your engine's parameters. Nobody I know of can recalibrate those chips. The distributor advance is controlled by the ECM, so if you don't like the distributor curve, tough t*tty. I don't even know if they make any custom chips for them anymore. They used to, but about all they did that I recall people saying that got them was advance the timing some. It may not LIKE the lower vacuum signals to the VAC/D/P sensor, or different temperatures that it sees, and may start throwing codes that it shouldn't throw.

The carburetor is trickier. The ECM does not care one bit about secondary operation or even if you have secondaries. It only concerns itself with the primary circuit. But then you run into issues in the fact that nobody I know of makes ECM rods/jets that you can mix and match. So if your engine demands more fuel, the ECM can only do so much. You may be able to trick the carb a little by widening the rod travel and goofing around with the rich side of the dwell signal slightly. But that only gets you so far. If you have issues after doing all that, again, tough t*tty. And I believe the 009 carburetor has a fixed rich stop that travels with the lean stop to keep your dwell window at 1/8" no matter what you do.

EVERYTHING has to work together. If not, you're going to have a tough time of it.

 

[john87442]

Ok this is great information also, 22 years ago I put a different cam in my 307 as much as I could with the parameters of air emissions and also bought a performance chip. However in regards to the vacuum and air/ fuel mixture or any other controlled ecm issue I was unaware of how or what was controlled or effected each other. So my engine is going to have a lumpy cam, 10:1 compression and not sure yet how much advance it will need. It sounds like I should not use the ecm at all and rely on a lockup kit for the 200r4 to keep the overdrive working. I should research more on everything the ecm controls. Thanks for the help! Always appreciate when you get involved.

 

[RabbitHoleSS]

If you dont wanna buy the kit, There should be a 4 pin plug on your transmission. Find the 1 that has 12v switched power from the ecm.Run a switch to ground out that 12v wire when u want to lockup the converter and connect the ground wire from that dame plug to a chassis ground.It's been like 10 years but I'm pretty sure thats how I did it as a teen on my cutlass with a 350/2004r swap. I had a switch right next to my shifter.

 

[69hurstolds]

The ECM controls your EFE on V6, rear carb vacuum break vacuum signal (who really cares unless you live near the North or South poles), ignition timing, EGR, ILC (on Y cars and other non-VIN 9 Oldses) and A.I.R. solenoid operations, certain A/C operations, carb mixture during idle through mid-range just short of secondary operations, transmission lock up, and cruise control among other things. It does this via sensors like coolant temperature, manifold vacuum/pressure, throttle position, and O2 (looking for higher temps for closed-loop). Everything working in unison to help with the engine running at peak efficiency and lowest emissions in various operating conditions.

That said, assuming you're running headers, and lumpy cam, etc., I'm going to surmise you'll likely need to be off the ECM. Which isn't hard, but it's almost like a sex change surgery to do it right. No going back once you cut it off. Meaning you'd have to disassemble/remove the ECM and supporting accessory wiring harnesses if you're going to make it a "show" car.

 

[Clone TIE Pilot]

Only the stock carburetor and distributor will work with the ECM. Many mechanics will try to talk you into removing the CCC system becausemost are no longer trained to work on them and don't want to learn besides the money they get from selling you extra parts. Its very hard to find a true professional.

As for exhaust headers, you can just weld an O2 sensor bung on any header you choose and use a 3 wire heated O2 sensor. You can also weld a stove pipe heater kif too fof the stock aircleaner for faster warmup.

 

[69hurstolds]

As for exhaust headers, you can just weld an O2 sensor bung on any header you choose and use a 3 wire heated O2 sensor.

You can try on an Olds. Probably won't do you much good. If headers are the only thing you change, then maybe. But not with a big cam too. O2 sensor will work, but it'll max out on the M/C solenoid and you won't have enough. Not to mention the vacuum signal that will muck things up.

My prediction- this car will be off the ECM. You can still tune the engine without it. You probably would still want an O2 bung on the exhaust so you can hook up a wideband O2 meter to help you get close for your new carb tuning. But the M/C solenoid? Nah. Don't see that in this particular car's future. Hope I'm proved wrong.

 

[john87442]

Thanks for all of that. This is a sunny day cruising around project, never going to see the track. I don’t have emissions checks so it’s long tube headers into duels. Wasn’t planning on catylitic conv. But I guess I’m relying more on the builder’s knowledge to supply what I was asking for. The conversation of overdrive or ecm function never came up and quite honestly it shows some of my ignorance. As I see it the ecm is gone and I’ll purchase a lockup kit for the 200r4. I know he said he’s going to get a hei distributor and I’m not too concerned about the a/c or cruise control.
But there’s a call to be made on Tuesday to get some clarification on what he has in mind…. It takes an act of god to actually catch him. Thanks for all the input hope this helps more than just me.