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My eagle won't get off the ground!!

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86erfixer:
Hey guys, my 86 wagon has a 258 I recently took apart for a cam swap. Let me rewind. I bought this car from a friend last year. I completely rewired it as it had a fire under the hood at some point and almost everything was either totally unable to recognize or not even there at all. But I managed to make it run enough to feel comfortable with buying it. My friend's dad owned the car and recently passed. He drove it from ny to Mexico every few years. At some point he had work done to it, but we weren't sure what. What was obvious was the tri-y header and offy intake with a 4 bbl Holley. I had it running "ok" once servicing the axles and brakes. But it always had a lack of bottom end, top end, if it could get there, and didn't like to start, didn't like hills....at all! Just a mess. So I rebuilt the 390 Holley and it got better, but not great. Doing so I realized the car had a single plane intake. So I opted for a cam swap.

Fast forward a year. I finally got around to the cam. It's a k68-231-4 comp cams kit. When I pulled the head, I found .030" slugs and a nice looking head as far as valves go. Put it all together and wow, it's.......better? Ish! So then I made a financial mistake and bought the dual plane dual port offy intake, using the same 390 vac secondary carb but now with adjustable secondary springs. It's an honest improvement. The problem was at first, I didn't have enough throttle cable so I ran the carb backwards on the intake, big runners for primaries, small ones for secondaries. It did alright. Sure it was short term. Did ok on pull offs and low end but still not good enough. And it would not by any means run cold, w
Even with a manual choke, I'd have to wedge the choke plate totally shut. But it started fine warm. So I finally got a cable, and a spacer so the carb throttle bracket would clear the intake, and voila, wait what? Nothing got better. Almost worse. So, in any combination, the best vacuum I could pull at idle was about 16". The lowest idle I could get was about 900 or so, yes I checked 18 times for vac leaks!! I upgraded the duraspark to hei and adjustable advance which is unhooked bc it refuses to idle and if it doesn't it stumbles on Accel when it is hooked up. I've changed the plugs twice and wires, even tried "recurving" the distributor. The only way it's really happy is at about 16 degrees base timing. I can go back to four before it stalls but then I lose response, power and it stumbles way harder in turns and driveway/parking lot maneuvers.

So I have this awesome car, that sucks to drive and doesn't like to start when cold or pull down low and loves stalling and stumbling. But it's a cool car and I wanna fix it and daily drive it. I'm almost ready to buy a sniper Holley kit but ohh boy idk.....anybody have any ideas or experience with 4 bbl 258's???? I could really use your help!!!!

mo.eagles:
Are you still running a cat? Check your exhaust for restrictions. If you can't exhaust then you can't build a vacuum.

86erfixer:
I got the car without a cat. It's all 2" into a turbo muffler. Not of the glass pack variety.

AMC of Houston:
A hot cam usually needs more initial advance (16 degrees is not uncommon) and maybe about 34 degrees total with mechanical advance figured in (I have a Clifford-equipped Gremmie that needs that much).  Hot cam also means less vacuum.  Idling at 800 to 1000 rpm isn't that unusual either - altho I haven't yet looked up the specs on your cam.

86erfixer:
It's more radical than a run of the mill eagle can but not crazy. The high idle doesn't bother me a whole lot but I can't run vac advance without base timing set at like 4 degrees when it's manifold vacuum. And if I hook it up ported I get a stumble shortly off idle . Almost as if the Accel pump isn't working but I verified that it is and if I adjust the advance I can make it better, but not better enough to go away. Are you using the vacuum advance on ur gremlin?

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