I know there were some here looking for how my carb swap turned out, so rather than having to dig through pages and pages in my 460 issues thread.... the swap went great!

The reason for the swap was because the stock Holley was flooding big time and instead of spending the cash and time to rebuild a 28 year old carb.... $320 bought me a brand new one. And worth every penny IMO.

Edelbrock Performer Series 750CFM Carb:
Edelbrock 1411 Edelbrock Performer Carburetors



Bolted the carb on right out of the box. Directions said no more than 6psi max fuel pressure and I was thinking the electronic in-tank fuel pumps I have are probably putting out more than that.... so I got a Holley 4.5-9psi fuel pressure regulator.


Holley 12-803 - Holley Fuel Pressure Regulators - Overview - SummitRacing.com





For the fuel supply, I ran 3/8" rubber fuel line. I ran from the fuel "diverter" valve (that sends excess fuel back to the tank) to an inline filter, then to the regulator, then to the carb.

Bolted on and truck runs great right out of the box. The only thing I had to adjust was the idle down a bit and the choke will have to be fine tuned on a colder day. The truck ran like crap, would not idle and was burning a TON of fuel with the bad stock carb. With the new one, it runs awesome, no more smoke, great throttle response, and idles like a purring kitten.

 

I will try to grab some pics of the install tonight. I can try to explain how I ran the vacuum since I am not using any of the emissions crap anymore. You also eliminate the choke hot air tubes, no need to plug the holes since it is a closed circuit inside the manifold. They just pull out. Top of intake mani, passenger side.

 

Looking forward to the pictures as well as a fuel mileage report. That's quite a bit of CFM capability so it will be interesting to compare your results with those lavatan is getting w/his 600 CFM on the 460.

 

Lots of people use 600 cfm carbs on 460's but if you think about it:

604 CFM on a 302 is 2 cfm per cubic inch
920 CFM on a 460 is 2 cfm per cubic inch

Just about everyone is running 600 cfm on 302's, yet how many people do you see running 900+ cfm on a 460? I'm beginning to think 750 cfm is in the ballpark.

 

Actually, that carb has secondaries that come on as far as the engine requires, so within reason you aren't going to over-carb. However, the smaller the CFM the smaller the primaries so the better the part-throttle response and metering, therefore potentially better MPG.

The other E'brock series, the Thunder, is the old Carter AVS, which stands for Air Valve Secondaries, and it has adjustable secondaries so you can easily tune when they come in. The Performer series is the AFB, which stands for Aluminum Four Barrel, and it was the go-to carb for many of us "back in the day". At least those of us who weren't into the Holley "stuff".

 

1. The carbs do self adjust somewhat, since most all are vacuum secondaries of one design or another. You can only force the engine to "see" the front 2 barrels, the engine won't open up the rear barrels if it's not ready for them.

2. The 460 in most trucks is a loafer. Low rpm grunt is it's main claim to fame. It doesn't need much carb because of this. A 302 is a little screamer. Not much of a truck engine, but it can be used if the gearing is right. It can use the 600 cfm because of the higher rpm it runs. The 460 can certainly use ALL of the 750cfm carb if it's personality is changed by engine changes and gearing changes.

 

The 460 came stock with a 600 CFM carb. The truck (since I have owned it) has not run with the Stock 600 CFM Holley, so I wont have anything to compare to, and it will be a couple weeks before the truck is street legal yet, but I will report some mileage numbers when I get it on the road.

 

Ok guys, as promised, I got some pics last night. They are taken with a cell and it was dark out, but they didnt turn out to bad.

New Carb:





Fuel routing: Just to the right of the distributor is the fuel bypass valve. This diverts unused fuel back to the tank since the pumps are always running. I ran hard pipe with flare and nut on one end out of there to make a nice 90* turn and then into the fuel hose and to the filter.



Then out of the filter and around the passenger side of the carb:



Then into the bottom and out one side (just plug the second outlet) of the fuel pressure regulator and into the carb. I mounted the regulator using the included bracket to the existing 2 bolts on top of the valve cover.



Here is a good shot of the plate on the top of the manifold below the carb (passenger side) that had two tubes connecting to the stock carb. They were hot air for the choke and are not used on this carb/choke. You can simply pull the tubes out of the plate and leave it because it is just a "loop" inside the manifold. (closed circuit) (no vacuum leak)



You can see in this picture the vacuum controlled thermostat houseing. It has three vacuum lines. One from the main vacuum port in the manifold, one to the distributor, and one from the timed port on the new carb. (front of carb, passenger side).



In the future, I plan to get a plain thermostat housing, and in that case, I will complete my simplification/elimination of all the vacuum crap and run from the timed port on the carb right to the distributor. I will also no longer have need for the main vacuum port in the intake manifold. Can plug that then too.


You can see here, the throttle linkage pops right on to the new carb. NOTE: this is a manual transmission. You automatic guys will need an extra little adapter for the transmission "kick down" not included.



Here you can see the block off place I made to eliminate the EGR valve. I used 1/2" aluminum plate and the gasket as a template. cut, trim, cut, trim, drill, and polish and install.



Lastly, The choke power and ground. Ground the choke to one of the 4 bolts holding down the carb. The instructions say NOT to use the existing choke power wire. (not enough juice?) But to find a new power source that is always hot when the ignition is on. I found a wire by the battery that fed the fuel pumps. Always hot when the ignition is on. Tapped in.



Good luck! and I will report some fuel mileage if I ever get to drive it.

 

The Carter AFB actually has mechanical secondaries with and air valve under the clusters. The air valve keeps the huge slug of air from leaning the mixture out too much. It's still not as nice a transition as the Holley vacuum actuation system. You probably don't really need the pressure regulator, your in-tank pumps are 6 psi if I remember correctly, they are centrifugal pumps, not gear pumps like EFI and are designed for a carburetor. If someone put EFI pumps in that would explain a lot of the flooding issues with the Holley.

I have used both types or carburetors and the best match I found for a 460 was the '69 428CJ 735cfm Holley. It is a 780cfm main body with special primary booster venturiis to step the primary air flow down to 345cfm.

 

The new fuel pumps I put in the tanks told me flow, but not pressure, so I wanted to be on the safe side. And the regulator was not that much coin. Good to know that I could eliminate it if I want though. Maybe I'll test with out it and see.

The reason the Holley was flooding was because it was simply shot. Needed a full rebuild. I was not confident doing it my self so the option was pay a local guy $200 to do it or send it to Holley and they would re-manufacture it for $300. Both options still leave me with an almost 30 year old carb/technology.

OOOORRRRR...... Spend $300 and about an hour to bolt this one one. Was the way to go in my case for sure.

 

Bump - Looks good. And apparently the width of the 460 resolves the throttle alignment problem created by the E'brock linkage setup. Bruno's experience with essentially that carb on a 351W had quite an angle at the throttle linkage.

About the vacuum connections to the dizzy, IIRC the temp control allowed manifold vacuum to the dizzy if the engine got hot, thereby increasing the idle speed and both the amount of coolant as well as air through the radiator. You might think about retaining that since it is already there - even though I agree with you that things look better w/o all of those hoses.

About the 30 year old technology, I hate to tell you but the E'brock design is every bit of that old. That carb is essentially the old Carter AFB, as I said earlier, and I think it came out in the late 50's. Having said that, I like the Carter designs better than Holley designs, so IMHO you did well in changing, you just didn't get a later design.

 

Thanks! I really cant wait to get this truck on the road.

I have this same setup on our 79 super cab as well. 460 with Edelbrock Performer 750 and an edelbrock intake mani that eliminates the egr and vacuum all together. It is running only the one vacuum line from the carb straight to the distributor. The only adjusting there was to get the choke to run high idle properly. Thermostat should control coolant temp/warm-up no? That is probably the most reliable starting motor (summer or winter) that we have. haha

 

Yes. The 'stat doesn't open until the operating temp is reached.

 

As far as carb technology, the Carter AFB and the Holley 4150 series came on the market in 1957, the 4180 was a later design for emissions. You haven't improved on the technology, just the age and wear.

 

Thanks for the info/pics.

Im still concerned about the 750 CFM, I think ill be going with the Edelbrock Thunder Series AVS Carburetors 650 CFM. It will have to wait until spring.