Holley Truck Avenger 470

So where do we sit on this, too big for the 258??????

I already have the HEI and the clifford 4v intake if that matters.

Opinions needed,

High5

 

i did the calculation for the 258 and it needs 373cfm
http://www.4secondsflat.com/Carb_CFM_Calculator.html

 

12^3 cubic inches per cubic foot = 1728 ci/cf

258/2 cubic inches / rev = 129ci/rev (four stroke engine!)

470cf/min * 1720ci/cf / 129ci/rev = 6267 rpm

Typically it's a little lower than that because your volumetric efficiency isn't 100%, so even with 80% VE, that's 5013 rpm. But that's probably a false reduction, because the stock cam and cylinder head are way more restrictive than the carb at those revs.

The problem with big carburetors on small engines is that there either isn't enough air flow at low speed to give a good vacuum signal, or the secondaries barely open because the vacuum would be so low if they did open.

I think you'd be much better off with the 32/36 Weber on a stock engine, or the 38 Weber with the 4.0L head. The 2100 Motorcraft always gets mentioned too - I have one on mine, it's ok, but I'm going with TBI as soon as I have a place to work.

 

I have the 2100 currently, but I have bought a 4.0 head conversion and have read that I will need more carb when I put it on. I was just trying to figure out what to do when I install the head.

High5

 

I have the 470, but my motor is bored 30 over, not much, but unfortunately the motor isnt in the Jeep for prlly another week, but my buddy put one on his and he is havin no problems, of course he doesnt really give a rats a$$ about gas mileage

 

The problem with Holleys is you either love them or hate them. I hated mine for about a year until I finally figured out how to tune it. I'm using the 2 bbl PN 0-7448. I think it flows around 350 cfm. I re-jetted it for my altitude (6,200 ft) put in the spring loaded float valve, put in a bowl vent baffle (whistle) and dropped the power valve down to a 55, and am using a Holley fuel pressure regulator set to about 2.5 - 3 psi. To properly tune a Holley you need to know you manifold vacumn. Holleys are the most tunable carburetors you can buy, but you have to invest the time in learning how to get them to run well.

 

How do you find out the new liter size of an eng. after bored over during rebuild? I have a 304 that has been bored .040 over

 

pi * (bore/2)^2 * stroke * 8 = cid

Approximately 61 cid / liter, or cid * (2.54 cm/in)^3 * 1 liter / 1000 cm^3 = displacement in liters.

 

Good thread:
http://www.earlycj5.com/forums/showthread.php?t=36010&highlight=470+truck+avenger

 

My problem isn't with tuning. I have always encountered flooding under severe fore/aft angles. And a have an intense dislike for diaphragm power valves, which have a habit of blowing and leaking, causing idle problems. As for tunability, I prefer switching metering rods and vacuum piston springs from the outside to constantly draining and removing the bowl to make changes. This holds especially true for the power circuit. Jayhawkclint, I have to say that the 2GC is one of the best carbs out there(see, now I've managed to get on EVERYBODY'S poopy list) Many times on my long road of carb experimentation, I have wished I'd have stayed with it. It doesn't flow enough(wish they had used the V8 version with the corresponding intake) but had be the best running carb I have run on my V6.

 

Pretty sure I've NEVER said the 2G was a bad carb. Quite the contrary. But comparing a 2G to a Holley is like comparing apples to oranges. A reformed Chebby addict, I've earned a few scars wrenching on small blocks; 283 with 2G is right up there with the Dauntless and Jeep 4.0EFI as one of my favorite engines of all time. What I will say about the Holley, however, is that I believe the 2 barrel 350/500cfm and 4 barrel square bore line of carbs to be the most tunable on the market, if you're into tinkering - you can adjust every aspect of fuel delivery from the time you turn the key all the way through WOT. You might call it the Ford 9" of carbs; there is an adjustment or a part for anything you could possibly want to do with it.

I run the 470TA on my 225OF. Some people say "that's just a poor choice, way too big a carb." I don't agree. There was a learning curve, to be certain, but: the JEEP makes a nice brown plug, I get 18mpg on the highway, it starts easily with the electric choke and drives like a car, it does not flood off road, there are parts and quality gaskets readily available everywhere (the Holley blue gaskets just can't be beat), and the reliability has been good. Not saying this is the carb for everyone, but it has been a good carb for me.

 

No kidding!!!

I have since moved on to fuel injection and will never look back.

This thread was from two years ago!!

High5