Glad you brought that up, I started looking at the olds 307 electronic quad after Mr. Sony mentioned the front Inlet.
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Wait, you are trying to fix a Dual-jet problem by replacing it with a Q-jet? Why not just fix the Dual-jet? I once had a 1980 Firebird, 301, 4 barrel, automatic, 2:58 gears, ran like a dead dog. So I tore into the Q-jet trying everything I knew about Q-jets to get it to perform. Total waste of time. At the same time I also had a 1979 Firebird, 301, 2 barrel, automatic, 3:08 gears. It ran great. Drove me crazy for a long time until I finally pulled my head out of my butt and realized that the 301 with a dead rear could not use a 4 barrel Q-jet. What I did was take another 2 barrel manifold I had, swapped it onto the '80 301. I found a nice Dual-jet in a junkyard, cleaned it up, and bolted it on. Wowsers!! The car came alive, pulled strong from idle to WOT. So what happened? Although they say a Dual-jet is basically the front half of a Q-jet, that is not exactly true. Yes, it looks the same, but the bore is larger, and it comes fitted with much richer jets and metering rods. It can handle a much broader power range than the primary side of a Q-jet. So what it comes down to is a case of fitting the punishment to the crime. A small motor with a dead rear comes with a 2 barrel for a very good reason- that's all it needs. My advice is fix the Dual-jet and when you get the 350 going, then make that a 4 barrel.
one thing you need is a good reason to do it, you will end up spending a good bit of money and time for no improvement in performance or fuel economy
As said, gear swap first. The 267 is a turd like the Olds 260 I have but mine runs great for what it is with dual exhaust, 10" open breather lid in the stock air filter housing helps a lot. Exceptable acceleration with 2.78 gears. The Olds 307 CCC carb should be close enough to work decent, they had a lean calibration. When you pull the intake, look at your intake ports, pretty sure they are shrunk for economy like the Olds 260. I sold my SP2P intake or I would be trying the same thing and probably gain very little. Good thing I have an Olds 350 with a cam swap should be pushing 300+ HP, 2004R mildly built with 2500 stall and 3.90 posi will round it out nicely.
If you do decide to get a q-jet, check out Quadrajet Power. Small shop in the Texas hill country. I got mine from him. He supplied the core. Check out his Facebook page (you don't have to have Facebook to do this - I don't have Facebook ). He seems to be very knowledgeable and detail oriented. He likely has a core. I haven't run my carb yet but the experience was good.
Can you elaborate on this a little more? Is this in reference to the bigger 350 Chevy, or applies equally to my 267? It would seem like a carb tuned for a 307 or 4.1 v6 would be a little closer to my 267.
Would rejetting and meter rods fix up an Olds carb for a 350 when I get there?
Qjets are application and engine specific. Different little passages (forget name) inside, different, well everything. Even from year to year on the same motor they can be different. The BEST solution, if you truly want to go 4bbl (which by the sounds of everyone else is a waste for this motor unless you work your way from the back to the front of the vehicle). An Olds carb will run BEST on an Olds engine, especially the engine it came from. a 307 carb will run different on a 350 and vice versa. Both are 750cfm, but the passages inside are different and built to the spes and purpose of that engine. A 307 H/O will have a different carb (as well as CC) than a Delta 88 with the same/similar 307.
But they can be tuned and fiddled with with rejetting and new rods to work on different motors, but unless you have a solid formula to work with it's trial and error and simply put just not worth the time and effort until you get a new motor.
Forgot those existed. Haven't sat down to play with a carb for a long time. Never really had to to be honest. And yes, that.
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