Another Conversion

[53 Catalina 292]

If you have the internals of a 7 wire big base distributor available, it is physically possible to mount them in the big base HEI 250 distributor. I did it last week, but haven't run it. It involved notching the base for the 4 wire harness, drilling mounting holes for the wider spacing of the ignition module - I gently used the mounting screws as taps - and another hole for a screw to replace the locating split pin for the cage (?) the pickup coil sits in. I let the "memory" of the pickup coil wires be my guide as to where that hole needed to be, (doesn't seem to be critical) and cut 3/16" brake tubing to space up from the distributor base to the locating hole of the cage (?) - I don't know what to call it - the first piece you put back on, after you've had it all apart. I did the same screw/ spacer arrangement for the mounting/grounding tab for the 4 wire harness just inside the distributor base. The three wire harness looks after itself. I put it in its notch in the base first, and worked from there. This leaves a gap where the vacuum advance went through the base, which I contemplate sealing with foil tape once the cap is on. I think it could work, if you haven't found the right one.

[53 Catalina 292]

Oops, sorry for all that blather, I missed your latest five posts somehow. Glad to see that you're making headway. What TBI system did you start with? I'm wanting to TBI my 69 292.

[r.e.c.enthusiasts]

Well its a the wire harness and all components are out of a 91 astro van. (ecu, sensors, wire harness, tbi) im still running thr old 1 bbl intake so i picked up a adapter plate online from 1bbl to gm tbi. The dizzy took almost 3 months to order factory but im glad i did. It is not modified at all. Mainly cause i wanted to get the wiring sorted out first. I think i need to do some eprom or something for proper tuning. As the astrovan is a 4.3 and mine is 4.1. However i think yours would probably be pretty much perfect for it?

[53 Catalina 292]

I think the 4.3 is 262 c.i., so your system has the capacity to fuel an engine 12 cubic inches bigger than the 250. Sounds close enough to me, in my vast ignorance. And the 305 c.i. system I have can supply 13 cubic inches bigger than my 292 (although mine is bored .060, giving a total of 298 or 299, I think - haven't done the math.) Also sounds close enough to me, in my vast ignorance. Your PROM, being from a 6 cylinder, seems to be what I would need to replace my 8 cylinder one with, though I don't even know if the PROM cares how many cylinders it's running, maybe just the displacement matters to it, and the distributor reports the number of cylinders. Know anything about that? Is there a number on your PROM that you can see, without much trouble?

[r.e.c.enthusiasts]

Hmm. Yea. Kinda feel retarded making that previous statement. But. Thats why im here as well. So as for the prom im not sure. But i will look at it when i get home Wednesday. Its still very accessible. (Uts the removable chip right? Lol)

[53 Catalina 292]

Hey, just being ignorant, that is, not in possession of all the facts, doesn't mean we're stupid, does it? Sir Winston Churchill, British Prime Minister, said to America, prior to its entry into World War II, "Give us the tools, and we'll finish the job." The tool we need is accurate pertinent information, which I'm confident the EFI GearHeads have. Somewhere. The answer to the question, "How do you eat an elephant?" being "One bite at a time.", I guess we make progress (learn) one question at a time. The PROM (for Programmable Read Only Memory, I believe) chip is the removable chip inside the PCM (Powertrain Control Module) a.k.a. ECM (Electronic etc.) ECU (...Unit) and "the aluminum box in a hard to access location inside the car that all the wires plug into." And I think when I read about "Calpak" it means the PROM. I welcome correction and clarification.

[r.e.c.enthusiasts]

Awesome. Yea the ecm has not been mounted yet so it will be easy to get to. Ill post that later today.