Technical Upgrade from Rochester 2G to Edelbrock 1406 worth it?

Yea.. it is honestly.. my career has me super overloaded and I typically tend to spend some of my holiday time putting work related inventions together (last two holiday seasons ended in 2 patents)... it wouldn't be a good use of my time to rebuild the rochester unless its a 1 day thing even though I know its the cheaper option.

 

That's what I read elsewhere two, however would the secondaries kick in going uphill? That's where I feel its a bit limited the most...

Rerouting fuel line/ linkage mods, don't worry me. The air cleaner I have fits the edelbrock (had already tried this a while back when I had another sbc 350 with edelbrock 1406 but that car was sold).

What I worry about is all the intricate small pieces on a carb or worn linkages/shafts/etc that need to come out or be replaced... I tend to be good with really small intricate things when I have time and don't feel super rushed or pressured and I feel stressed and pressured almost always these days, even during the holidays when I have time off. I feel I could put a new intake/carb quicker than rebuilding a carb but could be wrong.

Very true! I asked several questions to the ebay seller who says very unlikely to need a rebuild at all as it was working good when pulled... (of course that could also be untrue and id be in the same situation). I saw some remanufactured Edelbrock 1406 carbs for $270 on ebay. hmmmmmm....

 

$300 in questionable used parts, plus gaskets and then the labor to install all of it, hoping it will run, much less run better. Much more precious time wasted if it doesn’t run better.
Have you looked at the possibility of finding a local carb guy and give him the $300 to get it done right? PM lumpy63 and see if he can recommend anyone down there.

 

Rebuilding the two barrel will take about an hour to remove and disassemble. A couple hours, overnight to clean. A couple hours next day to "rebuild" and reassemble.
This is not a big project.
I doubt you could do the intake swap, set timing, tune edelbrock any faster.

 

Totally valid points! I did think about exactly this and thought I would be upgrading performance going with the intake and edelbrock so it would be worth the extra time however if I end up with a carb in worse shape you’re right I would be better off paying someone to rebuild the 2g carb! I may look into that! I will ask lumpy63

what about a remanufactured edelbrock 1406 for $270 with some warranty? I saw one on eBay for that much.. I saw a performer edelbrock intake for $100 and I’m not sure those are often in bad condition? Do they warp easily?

 

The 2 jet in my sons 61 was rebuilt by a 17year old
Just saying

 

ah ok that doesn’t sound too bad! I’m willing to spend that much time and if it’s worse off because I did something wrong I don’t care about the money since it’s minimal

 

I'd take a stab at rebuilding the 2 barrel first. Usually dirt and varnish in them. Not hard to do, check out Youtube. You mentioned that you didn't know the actual condition or mileage on the engine. Have you checked for timing chain slop? Rotate the balancer back and forth, and see how much it rotates before you get the rotor turning. Distributor runs off of the cam, so you'll see delay if there's a lot of stretch in the chain. Feel bad to add this to your list, but thought I should mention it.

 

If you’ve got 18” of vacuum at idle and it runs good you probably don’t have major air leaks at the throttle shafts or a warped base, etc. Closing and resetting the idle screws is probably clearing debris in the bowl. I’m 73, and going thru carbs with kits is what I did when I was 16. I don’t do it much anymore, but since we’re talking about stuff almost as old as me it hasn’t changed any.

It’s a truck with a tired but good engine. It’s going to be sluggish going uphill until you do more than a carb and intake. Slightly less sluggish, maybe. Worth the time and money?

Just rebuild the carb. It’s not rocket science. Then go enjoy the surf and the Home Depot.

 

I know I could overhaul a 2GC in a fraction of the time it would take me to swap an intake and carb to a different setup. I speak from experience.

I started around age 14. They always ran better after I worked on them, too.

 

The only advice I could give would be to consider some of the OP's post, AND do a compression test on the engine:

Time is important to the OP. When is it less costly in time to replace a known carb that probably needs a rebuild with an unknown carb that probably needs a rebuild along with the time to change manifold, etc.?

The OP states the engine may be tired. Compression test??? A four barrel over a large two barrel would probably give some improvement in WOT on a fresh engine, but a tired engine?

The OP states he just uses the truck to drive around San Diego; no major loading is mentioned. How often is WOT necessary?

As far as reliability is concerned, the Rochester two barrel has a cast iron throttle body; throttle shaft wear and clearance is virtually never an issue with the Rochester.

The OP was concerned about cleaning chemicals. While Dawn dishwater soap may be slower than some, it works and is safe. If you go with the aluminum carb, be very careful of other chemicals. Higher consentrations of even Simple Green will react with the aluminum.

As far as rebuilding is concerned, the Rochester two barrel is one of the easiest carburetors ever made to rebuild.

The engine is sluggish going up hills. Again, tired engine???; but what about differential gear ratio? What about tire radii? As someone mentioned, the two barrel will flow more air at anything less than WOT than the four barrel. The four barrel could be much more sluggish going up a hill.

All I have seen in the thread that suggests the four barrel is the way to go, is that it would seem the OP might wish to do so.

In any event, enjoy the truck.

Jon

 

I had the intention to check the timing chain slop when I had the distributor cap off and was doing valve seals but forgot. I'll do this to get a feel for what that slop looks like.

 

Thanks, to be honest I don't have much comparison for what a tired and untired sbc 350 is like in its stock form. I could be saying its tired when maybe it isn't... I just know going uphill my foot is pretty far down on the pedal... some of the hills in san diego can be rather steep and the one I take to get back home is pretty steep.

I test drove a different C-10 some years ago which had a sbc 327 and 4 barrel edelbrock and I went up a hill about as steep as the one referenced above and remember pushing the pedal nearly to the floor and it went ok but thought it could use a bit more power... the owner said thats what to expect from a sbc 327 and a heavy c-10 longbed truck... hmmm

 

What is the total advance / total timing?

 

Thanks so much for all of this super awesome insight that is allowing me to learn more and consider important points from an expert!

I'll need to do a compression test. I honestly don't know what a stock 350 in a c-10 truck should feel like in its tired or untired state. I may be describing my engine as tired when in fact maybe it isn't. I don't have any reference to compare to. I have a sbc 350 in my chopped 50 ford that has headers, was rebuilt, a 4 barrel holley carb and not sure what kind of cam (if mild or stock/etc). I haven't had a chance to drive it much for a comparison though.

As far as WOT. I only tend to be pushing the pedal far and almost to where it bottoms out when going up a hill and I'm usually at about 45 mph in that state on a rather steep hill (not sure the inclination). I don't think I'm at WOT even if I floor the pedal because the travel on the pedal bottoms out and the carb throttle is maybe 75% of the way. I had tinkered with this and extended the pedal arm so it goes to near 100% when the pedal is floored but found it to be too sensitive so I put it back how I had it.

I have a TH350 and what appears to be a stock rear end and could be 3.73:1 , 3.07:1 or 4.11:1 ratio. I haven't had time to take the rear cover to actually check what the rear end ratio is.

I have P235 tires so 28.9 inch diameter.

I'm guessing the 4 barrel won't help me much unless im on the freeway? I try to avoid freeways like the plague in san diego, too stressful with this truck and my shoebox ford.

I'm seeing it may be better to rebuild the rochester and if it doesn't come out right it won't cost much and I can just have someone do it professionally.

 

I need to check that carefully at 3000 rpm using a tach and dialback/timing tape but I remember revving it quite a bit and being somewhere near the 36 deg mark when I last set the timing with about 14 deg btdc at idle and vac canister disconnected.

 

Rebuild the carb. It is no big deal.

 

Back to the not knowing if the engine is really tired or not just based on how it feels... the stock 1975 SBC 350 with smog gear was rated at 145 hp. I put an HEI in it, and set the initial timing to 14 btdc so maybe I made a little more HP, not sure. There is no smog gear in this engine.

Perhaps the longbed C10 being 4400 to 5000 lbs with only 145 hp would feel like it had a tired engine going up an estimated 15% grade hill?

I will have to do a compression test...

My 2009 Nissan Xterra has a curb weight of 4400 lbs but has a 260 hp 4.0L V6 and optimal gear ratio from factory.. it makes it up the same hill fine but I wouldn't say it feels super powerful doing it. Perhaps I'm more used to that and the truck feels sluggish because the 350 in it has a lot less hp and is old and perhaps the gearing.

 

Rebuilding the 2bl can't hurt.

Having to readjust things could be air bleeds , vents and such .

If it's not burning oil and has good compression it might have a worn cam .

Most trucks have a 4bbl and would not hurt if the rest of the engine checks out .

 

Thanks, could be worn cam if compression checks out. At the same time this is a smog era engine with the not so good cam, heads and domed pistons. Maybe I'm just feeling a motor with low HP going uphill.. although I wouldn't be surprised if there is wear in the cam or compression isn't good as this truck had so many hacked up things when I got it.

 

Like carbking mentioned above, it might be helpful to know what the rear axle ratio is. With higher gearing, some tall tires and a low stall stock torque converter, even with a 4bbl carb and intake it's likely to still feel a bit sluggish pulling up a grade with a load in the bed. Unless you really plant your foot in it and drop it down into 2nd gear . . .

 

https://www.youtube.com/results?search_query=rochester+2g+rebuild

 

I have never been disappointed by a 4bbl swap on a 2bbl engine. That being said, there is nothing worse than a used carb that someone screwed up. You just never know when buying used parts.
A good working pre emissions Q-jet would perform well on your truck but they are much more difficult to rebuild than the 2gc.

 

Please forgive my bluntness but you were already thoroughly encouraged to clean that carburetor in a previous thread, stop overthinking all this stuff and just hose it out really well with a couple cans of carb cleaner and blow out the holes with compressed air. Put the basic rebuild parts in it. Then you know you at least have a good clean carburetor and you can go from there. We can theoreticize all day about every single possibilty of worn parts. If I remember right you posted a picture of the inside of that 2bbl and it was brown. Do the basic de-gunking of what you have and then decide if you want to spend money on upgrades. I understand getting overwhelmed with intricate details but this stuff really isn't rocket science, crack the thing open and if you get stuck we'll help you. Somewhere online there's an exploded diagram of that carb that shows how all the pieces go together.

 

Take an hour to clean it and be done. If you're still not happy with it then you already have practice cleaning the used Edelbrock before installing it.

 

My brother-in-law (at the time) had a ‘78 or ‘79 Chevy 1/2 ton pickup. 350 and quadrajet carburetor.
He was often pulling a horse trailer, and needed more “oomph”. I didn’t want to deal with putting headers on it, cam swap, etc. I saw a used Performer in the paper for 50 bucks (this was late ‘90’s) picked it up for him and put it on with his original carburetor.
A few weeks later he called me and told me his truck (TH350) didn’t down shift and more pulling some hills, etc.
He wasn’t hotrodding, etc, but it (according to him) seemed to add enough torque to make him happy with it.
Will you get the same response? I dunno, could have been when I put the intake on just adjusting the timing was all that was needed, never checked it before the swap.

 

I used to sit at my kitchen table and assemble them on a place mat. Cleaning them is the key element to having them run right. In 1975, I bought a new one at a parts store for $36, it was worth it.

I had an adapter (and still do) to run the Holley 4412 in place of the 2GC on the stock cars, I ran one on the street in a pinch with a manual choke.

 

first of all you need to check the #s on your engine. i find it hard to believe that a 2gc is orig to a 350. but who knows what has been done to the since the engine trans were not even available un till 1969 Tom

 

Speed reading, Tom?