1978 Caprice, the new on-going project! (Yes, I'm still alive!)

[gadget73]

Used carbs are only useful as a rebuildable core. I've frankly never had one that was worth using without an overhaul unless it came off a known running perfect engine a week prior. Any amount of sitting just turns them to shit.

[sly]

shiny!

[murphmobile2]

I'm officially running out of time before the snow moves in, and I need to get it drivable so I can get it ready for storage.

The "new" carb was put on yesterday and it was leaking gas from multiple spots and also had none of the proper throttle linkages, so I just said screw it and bought a new carb. Same model, Holley 4160, 600 cfm. It was only $269 after my discount through work. I'd like to keep with the 600, so that way I can also use it later down the road too.

After he put the new one on, it fired right up like it's supposed to, so I'll be picking it up this afternoon!

I didn't want to spend the money, but I need it running and I'm done messing with it.

Here's a quick shot of it that he sent me from last night...



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[88Vic]

Probably a 500 would be fine with the cam this 305 has. I had a 600 on my 350/290 in my C10 and it was enough for it. Would've rather had a Holley that I could tune, it was an Edelbrock Performer but it was fine for driving around.

[DerekTheGreat]

Yep. That book has a little calculation thing for how much carb you need. Doesn't take into account cam or anything, pretty much just displacement & RPM. Based on that my car should be running something like 550 IIRC. I bought that carb thinking it was a 650, when I decoded it after doing that math I was somewhat happier knowing it's actually a 600. Book states it's better to have a smaller carb than a bigger one.

[gadget73]

A 390 cfm would probably do quite nice on a 305. A common mistake with motors is going too big on the carby.

[DerekTheGreat]

If carbs are "bad" they can usually be rebuilt for much cheaper than a new one. I've got a 4160 Holley on my cammed 318 Plymouth, it's a 600cfm and that might be a tad too much. To me it's the poverty model as it doesn't have a metering block for the secondaries. It'll do just fine but you just get what you get in terms of flow, unless you want to drill and I don't recommend that. In your case while the carb is not on the car I would open that bad boy up to see what you've got in terms of main jets, power valve & the color of spring used for the secondaries. Do not take a carb that was running great on another engine and expect it to run great with your set up. You're going to have to mess around with accelerator pump cams, nozzles, main jets, idle mixture screws, secondary spring rates and the power valve to get the most out of it. The air horn (Thing the choke is mounted to) will have the serial number on it which will tell you exactly what you've got. If you don't already have a guide to help you along I can recommend at least one book that will get you up to speed, helped clear up much of my ignorance. You're going to want a vacuum gauge, Holley jet kit, accelerator pump cams, the quick change secondary spring kit, some power valves (once you figure out what kind of vacuum you get from your engine) and then some of those blue reusable float bowl gaskets and the little gaskets for the bolts that hold it on. You've got some fun ahead of you

[murphmobile2]

Well, had problems keeping it running and had been diagnosing it the past two weeks... Found out the carb I had was no good. Traded it off for another 4160 Holley, so we'll see how this one does.



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[DerekTheGreat]

The V belt nonsense in the late 70s had gotten pretty bad. Motors had way too many things to drive in a sane manner with so many different belts. It sure was easier when they finally went serpentine in the 80s.

This. Good god it was bad, wonder why it took so long for someone to think, "Gee, wouldn't it be nice to have one belt do everything?"

[88Vic]

From the pic above it looks like just the ps pulley is offset. I would think there's an aftermarket pulley out there that's further out to make it fit, something like a long snout pulley, or maybe pulley spacer. It'd be worth looking into, much less hassle to run 1 belt. I don't like the 2 belt setup on the lopo, if I were gonna keep my car I'd be removing the a/c and smog since a/c isn't working and just leave it with one.

[gadget73]

the offsets are all different so the multiple belts can pass each other. More likely he'd need a complete new set of brackets to make that work.

[88Vic]

Should be pretty easy to route a serpentine belt for wp, alt and p/s only on a small block, probably a diagram and belt length floating around out there somewhere. Might have to search on a hot rodder forum, ask those guys because it's a common setup for hot rods.

[gadget73]

The V belt nonsense in the late 70s had gotten pretty bad. Motors had way too many things to drive in a sane manner with so many different belts. It sure was easier when they finally went serpentine in the 80s.

[murphmobile2]

I think I'll fab up a bracket for it, I ran it without one for a while and didn't have any problems though. But, that also means nothing...

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[gadget73]

what are you doing for the missing power steering bracket? Those things tend to flex and make the belt jump or scream if the bracket that went to the exhaust manifold is missing. I believe you might be able to fake it if you make a spacer to go between the header and the bracket tho. They also tend to scream if the AC is missing since the second belt on the PS pump is the AC belt, unless you have alternate belt routing to get both belts on without the compressor.