Clifford Vs Offy

-
The Offy 4bbl intake manifold has provisions to bolt to a stock exhaust manifold and provide the carb heat.

The Clifford 4bbl intake does not have provisions for the carb heat and it can't be used with a stock exhaust manifold.
 
YES, you can use a clifford with a stock exhaust manifold!
The main difference between the clifford and the offie are the size of the plenum. The clifford has a much larger plenum and the runners start out much larger and taper down. The clifford is better for high rpm HP than the offie. The offie has a small plenum and the runners are small like a stock intake it is better if you are looking to have more low end torque.
SO do you want to do burn outs or drag race?
 
This is a bit off-topic, but have you considered the Super Six set-up? For a stock engine, it's a great upgrade from the 1 barrel intake.
 
70Valiant said:
YES, you can use a clifford with a stock exhaust manifold!
Click to expand...

Are you sure about that? The one Clifford 4bbl manifold I have seen does not have the gasket surface on the bottom or the bolt holes to attach a stock manifold to it, plus, Clifford says it can't be used with the stock exhaust either.

I had an Offy on my \6 with headers and a 390 cfm vacuum secondary 4bbl. This combination with a Comp 252S cam made for a good street combination.
 
I think I'm More of a burnout guy , than a High RPM Horsepower type.
Yes I am also looking at the Super Six Conversion. My main concern is that these manifolds are going for about the same amount as the 4bbl ones on-line, and can't produce as much HP. I don't really have a local yard that holds on to older cars here, most only go back as far as the late 80's if your lucky.

Sounds like an offy with Dutra Duals (For Carb Heat) is my plan at this point.

Robb
 
.

Sounds like an offy with Dutra Duals (For Carb Heat) is my plan at this point.

Sounds good.
Add a 390 Holley and your rolling nicely.
Next up would be the head.Bigger valves,shaved,ported.........
You are on the right track though.

Picture 263.jpg
 
Thats a clean slant 6 !

I though the Clifords manifold was a copy of the Hyper pack intake ?
 
My clifford does have a mounting suface on the under side but I was wrong it is for mounting a hot water heat sourse not an exhaust manifold. Sorry my bad.
Direct carb heat isn't really that important. If you are pulling heated air from around the headers on startup you should be fine. Between the heated air coming in to the aircleaner and the radiant heat of the headers mine warms up to operaing temperature very quickly. That is how I have had mine setup for winter driving for years. Right now I don't even have a choke. Once it starts I just hold the throttle at 1800rpm and count to 100 then off I go.
There is a super six setup for sale over at slantsix.org it includes Intake, exhaust, carb and aircleaner but no kickdown.
 
AdamR said:
Thats a clean slant 6 !

I though the Clifords manifold was a copy of the Hyper pack intake ?
Click to expand...
Thanks Adam,
This is Cliffords regular 4 bbl intake.They do make a copy of the original hyper-pac.The regular 4bbl has much better street manners.The long runners of the HP like to be opened up out on the highway.
 
The Clifford manifold is designed for use with headers only while the Offy 4bbl is designed to bolt up to the OEM exhaust manifold. Although I don't have any experience with the Clifford manifold, my understanding is that its passages are larger and better suited to higher RPMs. The Clifford also includes a provision for water heat, which they recommend for street use.

The Hyper-Pak intake manifold now manufactured by Clifford is a Doug Dutra reproduction. From what I've read about it so far, getting good driveability and/or power takes a bit of work.

On my 65 Barracuda, I started off with an Offy 4bbl intake and a 625 CFM AFB with headers. I found that no matter what I did with the accelerator pump shot, I would always have an off-idle bog. After some research, I found that I could just about eliminate it with a metering rod with an extremely rich power step. The problem turned out to be that my lack of intake heat caused the fuel to drop out of the airstream. The extremely rich power mixture made up for the fuel that puddled on the intake floor when I hit the gas. As a result, I built intake manifold heater to maintain a hot spot underneath the carburetor. With this heater, I experience absolutely no bog with the 750 CFM Quadrajet I'm currently running.

Gasoline produces a refrigeration effect as it vaporizes in the intake manifold. This means that the manifold becomes very cold on an engine with headers right after startup. The cylinder head supplies heat to the intake manifold once it is warm, but this is inefficient because the heat doesn't transfer all that well across the gasket and the heat travels through the intake runners. Ideally, there should be a hot spot under the carb to vaporize any fuel that drops out of the airstream as it makes the sharp 90° turn from the carb to the intake manifold.

DutraDualsHeaterJPG.jpg
 
I am running clifford headers with my clifford intake. As you can see from the pic the header pipes from 4,5,6 all run directly under the center of the intake. Within a few minutes of driving my intake is too hot to touch for more than a few seconds, even in cold weather. I believe your dual Dutra Duals do not heat the intake as well as the headers.
MVC-005F.JPG
 
I have the option of hooking the water up to my Clifford intake.I live in Cal and have never seen any reason to.Just takes a couple extra minutes to "fully" warm up.

Holy Cow !!!!!! 750 quadrajet.Sounds like to much carb.Some of the small blocks on here dont run that big a carb.

Have you ever tried a Holley 390 or a EDE 500?
Im sure as you know,thats what most of the /6 guys are running.

Picture 264.jpg
 
I have the Clifford with duel 2bbl and header
 

Attachments

  • 10448200_258815397575785_6884883661769522794_n.jpg
    59.1 KB · Views: 402
Huh????. Dude, did You just step out of a DeLorean w/a surface temp. of 1200degF??
This thread is 9 years old,and primarily looking for advice on which std. 4bbl. intake to
suit his needs.
Not that I'm not interested in your build, and how it runs, but..........
:glasses7:
 
Dang, I gotta start looking at the dates of these posts..........
 
If I come into money, I'd consider this. What other mods have you done? How is it to tune? How are the street manners?
 
You must log in or register to reply here.
-

Back
Top