only thing wrong with above diagram is how the coil is shown. It shows as integral to the dist cap, when tbi is clearly not, and has 3 more connectors to pin out with separate coil and secondary ignition cable
CK5
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TBI won't fire up
- Thread starter Mastiff
- Start date
Yes, generally these things are wired up the same, the only real differences I can think of TBI-wise are the inlet air temp sensor in cars, and the way VSS was accomplished through the years and cars vs. trucks. Pretty sure TBI of all types stayed essentially the same until it was almost completely phased out in 1995.
I suppose you'd need to consider that the electronic transmissions also had a PCM vs. ECM, so that would have changed wiring significantly in those applications, but still probably not much at all for the engine side of things.
Really unfortunate GM didn't just put TPI in every vehicle with a 5 or 5.7l 1985-1991. Almost no difference in engine components. Repair would have been a breeze, and parts would have been super cheap. On the surface cost may have been a factor, but I can't believe running carbs, TBI, and TPI all at the same time was cheaper than having one engine do it all, especially when warranty work was factored in.
Edit: I definitely thought Wes was wrong about the caps/coils, but apparently that changed even in cars in 1987. If 1987 or later and FI, either TBI or TPI, it was a remote coil.
I suppose you'd need to consider that the electronic transmissions also had a PCM vs. ECM, so that would have changed wiring significantly in those applications, but still probably not much at all for the engine side of things.
Really unfortunate GM didn't just put TPI in every vehicle with a 5 or 5.7l 1985-1991. Almost no difference in engine components. Repair would have been a breeze, and parts would have been super cheap. On the surface cost may have been a factor, but I can't believe running carbs, TBI, and TPI all at the same time was cheaper than having one engine do it all, especially when warranty work was factored in.
Edit: I definitely thought Wes was wrong about the caps/coils, but apparently that changed even in cars in 1987. If 1987 or later and FI, either TBI or TPI, it was a remote coil.
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All I can think of for so many different induction systems. The Tune port injection was Bosh patents, many of the 84-87 tpi, crossfire, and the 3.8 Buick tpi (the 86 3.8l tpi had coil in cap dist) I worked on in 87 at gm was all Bosh. So they would have been paying Bosh a royalty even when after switched to full GM systems. I forget the exact 1st year for the Cadillac electronic injection but I will say 78, in 80 the C4 system 81 the CCC, 84 the crossfire injection, 85-86 tpi and tbi. This was lighting fast changes in and industry that hadn't changed much of anything since the 50's I mean electronic Ignition and voltage regulators in the 70's. I will say GM computers system were the best out of the big 3, esp after the protected the device quad drivers from shorting out if solenoid shorted. I think the trucks stayed ccc till the gmt400 was released mid 87, mostly to use up parts. Allow the suppliers change over time. The tbi was all GM no Bosh left overs, so no royalities. The engine in midest of this that was cool the Quad 4, crazy power in 2L simple controls, once you got past the timing chain. Was good thing I was young and could retian well cause there was a lot to retian, changed sometimes monthly
I have this cool diagram in my notes from way back. Not sure the source, maybe gearhead-efi. It shows the two relays with one of them tapping +12V from the key power at the coil like my current harness. The specific onnectors to the coil and distributor aren't made explicit though.
I like it. Stole it. So you can certainly do 2 relays, I think the second relay is mostly for the heated O2 sensors, and they used for a clean ignition 12v source since they had it for the O2 heaters.
I am not sure what original application is either, the pink with black should be feeding all the sensors and actuators. Ah I see in foot note IH scout with 454, this must be someones custom loom. nice documentation for end user
I am not sure what original application is either, the pink with black should be feeding all the sensors and actuators. Ah I see in foot note IH scout with 454, this must be someones custom loom. nice documentation for end user
The only thing I would avoid is having the coil connectors pointing up, as they could take in water over time. Standard practice is to make a drip loop in the wires. They come out of a horizontal connector and go down slightly so any condensing water drips off there and not at the connector seal.
I was talking about if I rotate the distributor base so the connectors face in a more convenient direction.
I've got one of those intakes, since they injected the Olds small block for the Cadillacs. I want to say 76 was the first year, but it's been awhile since Ive even thought about it. Bottom of my list of projects, but intend to use as much of the original setup as I can to port inject the Olds small block, with a BBC throttle body for air control. Need to have a thin adapter plate made (to still fit under the hood) for the TBI and open up the intake bores to match.
Its a race to see if that can get done before I'm too old to enjoy it. But way off topic lol.
76 is when the olds became the corporate motor, Caddy owners got all up in arms say they spending Caddy dollar on an olds engine, then the 4.2 aluminum with dfi came out 82 ish ? in both front and rwd models, and let not forget the 8 6 4 that eventually was modded to just 8. sorry for the High jack
As for clocking the dist I think you find the dia I posted has the best position. any where else the will components in the way or firewall
All my harness connections are coming in from passenger side. If I put it in the factory spot I'd probably need to extend the pigtails on the new connector to reach (4 black wires going to current oversize connector). Not a big deal, but that's why I'm thinking about it. And that oil pressure switch might be tight.
yeah looks like you've got big oil pressure sensor on DS too. Where ever you make things fit.
Where did you guys with conversions mount your coil? I've thought of 3 options, none of which I'm super happy about:
(1) fab up a mount that connects to the single vertical bolt holding throttle cable bracket, this bolt is solid but the whole thing would be subject to rotating
(2) fab up a mount that attaches to the throttle cable bracket itself. Would probably work but would look hacky
(3) mount to firewall. Would require some sort of insert or something since I wouldn't trust sheet metal screws for this over the long haul. No existing bolts/screws are close enough or up to the task
(1) fab up a mount that connects to the single vertical bolt holding throttle cable bracket, this bolt is solid but the whole thing would be subject to rotating
(2) fab up a mount that attaches to the throttle cable bracket itself. Would probably work but would look hacky
(3) mount to firewall. Would require some sort of insert or something since I wouldn't trust sheet metal screws for this over the long haul. No existing bolts/screws are close enough or up to the task
what under the rag in the pic between the fuel lines on the intake ?
Throttle body with air cleaner off.
yeah just behind the tbi between the fuel lines, what does the intake have right there.
Circled area? Nothing is there I think, except a vacuum port. The arrow is pointing at the cable bracket hold down bolt that might be candidate.
Here's a better view:
Is that a GM intake ? Or after market
Edelbrock performer from my Quadrajet days, with adapter.
yeah it won't have bolt bosses for a tbi coil
