I'm rebuilding my worn out 460, going to a 466 with a comp cams xtreme 4X4 cam 34-243-5, weiand stealth intake, headers, 3 inch exhaust. and i'm kind of stuck on what carb to use, i've been told i should use around an 850 but the only 850's i can find are holly's and I wont use a holly. any sugestions?

 

Then use a Demon:



850 and that small cam might cause some slow air speed and a poor booster signal. So off idle response may not be as snappy as it can be, considering a reasonable compression ratio.

If you are running mud, then power is the name of the game, so you might stongly consider the Holley, or at least a Holley design / style. This is where the power is at.

 

So do you think I could get away with an 800 or what would you suggest? The engine is also getting balanced and i'll be porting the heads. 9.5 to 1 compession and a high volume fuel pump.

 

Which heads are you running? What size valves will it have? Rocker ratio etc. Home brew port jobs can be good and bad at the same time. I mean, it does not take much to ruin a set of heads. Strike water or move too much material in the bowl can ruin the quench area and you will have problems.
9.5:1 seems a little on the low side. Is there a reason why you are being this conservative? I would imagine that you could get away with more compression.
Add some compression and you will really wake a sleeping giant.

For carb selection, you can use advertised CFM ratings, but understand how the carbs are flow tested for total flow verification.

YouTube - Carburetor Flow Testing

Dry flow VS wet flow testing will net different figures. Many Holley uses, or even Demon users run big CFM numbers and come up with a poor running engine. UNderstand that the Demon is wet flow tested and will outflow standard carbs that are normaly dry flow tested. A 750 Demon will net over 900 (dry) CFM, which is how other manufacturers test their carbs.
This is also why sizing a Demon is fairly critical. While I dont believe that one can over carburate and engine, I do feel that a carb that is too large can lead to poor tuning and poor throttle response. Small is good, provided that you can run the big CFM numbers when the engine is at wide open throttle. Also understand that the engine does not run at WOT all of the time, and most vehicle will be under some sort of load and will have to be at part throttle for any given period of time.
For a basic 466 non roller motor with relatively stock heads, a small cam (not being critical, probably should have said conservative) and fairly low compression, I would stay within the 700 to 750 range, and would not exceed 750 if using a Demon.

You mentioned that you did not want to even consider the Holley style carb. Why is that?

 

Most people dislike Holleys. It seems to me, whenever there is a carburator problem its always been a Holley.

Edit:
Well I shouldn't say most people. But, there are some unhappy customers out there. (Like most things..)

 

i think the dislike is similar to the qjet's, they can be finicky to tune right, once they are they are awesome, but not alot of people have the patience to learn how and to tinker till its right, pull it out of the box and put it on seems to be what most people want.

 

I tend to agree, with the fact that most folks do not want to tinker. Unfortunately, these folks dont find or even desire to seek out the point where a slight tweek can make a difference.
Most just throw something together and hope that the driveability, power, and reliability just happen.
I run Demons, and I prefer them. I can say that I prefer them because I have used several combinations of other carbs, and have gone through the trials and errors, to determine what works well, and what simply gets by.
I dont, nor will I ever agree with the fact that a certain design is any more or less reliable, or dirveable than another. I am a guy that does not even run a choke horn.
Jump in any one of my piles of junk, and without hesitation, the things fire right up. Heak they even idle right away. Yes it takes a bit of tuning to get any carb this way, but remember that I have run just about every type and I have a little bit of experience with what has been successful.
I even have a couple of Predator carbs. Believe it or not they run pretty good. I just cant seem to get them diald in just right over a broad range. Darn things make some great top end power. However the narrow range of powe makes them less than desirable for my applications.
I an say that the Demons that I run, fit the bill, and qualify as a great carb, that is easy as pie to tune. I have left one carb alone for two seasons now, and not even touched a single adjustment screw. It just runs, and runs well.

 

I'm running lower compression because thats all that cam called for was 9.5-1. the truck is going to see the street as well as offroad, and will do some idleing in the bush so my thinking was that more compression is more heat. I have heard nothing but bad things about running a holley offroad, i have had good luck with my old 750 carter and my 600 edlebrock. You say that cam is a conservative cam? The machine shop that has my block said that cam might be a little too high strung for the street?

 

Demons or quickfuel good carb and decent priced. What ignition system are you gonna run. MSD is good stuff. I would up the compression but you would need 91 octane fuel all the time in summer maybe 88 in a non loaded situation. What is your elevation and climate. Sounds like nice 460 but I would run a solid cam for mud runner.

 

If you like the Demons you might want to buy some now to help them come out of Chapter 11 and survive.

 

people that dont like holleys because of having to tune them are just fooling themselves...first off the screws on the side are just for making it idle smooth...any other tuning to a holley (and most other carbs too) can only be properly done on a dyno with a wide band air fuel meter, then u can run it and change jets accordingly...i work in a speed shop and see guys ready to throw their Holleys in the trash for an edlebrock or whatever..after two pulls on the dyno we can iron out most kinks in the fuel system with ease.......if you want bolt on dependability, your best bet is a demon...but even when we sell those the vehicle has to go on the dyno to be dialed in...only occasionally does ANY motor run spot on without a couple dyno runs....

 

Where I live and play a handheld 02 meter works well. My situation is elevation changes like 4000' to 9000'. A dyno would be great if one was near me. I basically have to set up lean for when I play at higher elevations. My town is 3700' elevation and everything around is up from me.

 

Your altitude and terrain in Wyoming are much the same as mine are here in Nevada.Altitude changes can be a pain for tuning.I run Q jets on all of my rigs,but im kinda wierd.

 

That cam, while way on the conservitive side for a full out mud racer, is not that bad of a cam for a general purpose streetable 460 based motor. For fuel economy on the street run a 750 vacuum secondary. If you want a little more performance, do to a dp. If you want to race it, run a 850dp. My last motor was a stock bottom end 460 with ported D3 heads, stealth intake, Holley 850dp and the a Comp xtreme marine 7274h cam (similar cam just a little more duration and lobe seperation). The truck ran great, and to be honest I had to jet it way down to make it run right as out of the box the 850 was way rich with the 72/72 jets.

You don't say what heads you will be running, but assuming you have the typical D3's, with a zero decked block on a flat top piston, deck the heads .030 and you will be around 10.5:1. If you are concerend with a lot of idling time and not an all out race vehicle, just get yourself a Quickfuel 750 and call it good. If fuel consumption is not a concern and you want more power when you drop the hammer, then get a quickfuel 850. Or PM me, I might be selling my holley 850 because I need to step up to a 1050 Dommy

 

actually im running the stock 1985 iron heads... porting the exhaust side and they have been machined to run better springs. my compression is around 9.5-1. its not an all out race truck, its more of a street and offroad truck. im going to give the 800cfm edlebrock a try with a high volume fuel pump and see where that goes. i"ll be running stock igniton to.