Intake Manifold! Edelbrock or Offy? which is the best??

[Austrian455]

Hey fellas,

At the moment I´ve got two manifolds for my buick. A Edelbrock Performer and a Offenhauser Dual Quad.

If I´m going to use the Performer I would rebuild the stock 800CFM Q-Jet.

If I use the Offenhauser I don´t know which carbs I should use. I´ve got two 600 CFM Holley. Are two 600´s to much?
Has anyone experience with a dual quad set up?

What to do with the EGR. (It´s a 72).
I want to remove that stuff. But what about the EGR runners? On the Performer they are closed, on the Offy they are open.

What to do??:confused4:

[centurion 455 ragtop]

First off, what is your goal and what car is it going on. Being your on this site I would assume it is your Centurion.

What would be your use of the car.

Do you want to do a lot of cruising?
Daily driver?
Occassional driver?
Are you going to race it often?
Do you want the dual carbs for the "WOW" factor?

Emission Laws
Your yearly car inspection, do your have strict emission laws

Fuel Costs Concerns

Biggy here. If you use it as a daily driver dual carbs will drink a lot of fuel on local driving.
Or you don't mind that it will eat much more fuel.

Mechanically Skilled

Do you do your own tunning and work on your engine and car.

All of the above factors should be thought out first. The use of your car being the number one factor. Now if it's a cruiser and you want the lowest end of maintenance I see no problem with a single carb intake. The dual carb setup may end up being costly. But if you like to attend cruises or to some shows and pop the hood get the cool looks, well a dual setup on a big car is different and looks good. Performance wise, a single can equal or out perform a dual setup so in that question its a toss up. Take a look at Adams Coupe, a single carb and it runs great at the track.

Example on goals, being my setup.

I would love to have my Centurion run like a raped ape, like Adams coupe or Nick Rabi's convertible. Would love to race it on the track sometimes, and some street light action too. When I was re-building the engine (did it myself) I factored in uses. I tow my track car with it and I love to go on long trips with the top down with the kids or just cruising. And of course the rising fuel costs all played a roll on me retaining the 2.73 rear gears, and keeping it with a stock replacement carb. I decided on sticking with replacement low compression pistons. I did try a aftermarket single aluminum intake. It ended up making the engine on start ups cold with rough starts and fuel economy suffered. I since re-installed the factory intake. I did have the heads converted to the Stage 1 heads with slight port work, plus I had a mid range cam for higher torque at a lower rpm which is better for towing.

End result is cruising highway driving with the ac going I get about 17 mpg. Towing I get 10 mpg. Towing with the ac on...:Dou: just know its way under 10, I can actually watch the gas gauge going down! Loaded up I estimate the towing weight is close to or about 5,000 pounds. While cruising without the ac going and not towing I can use regular 87 octane fuel, it won't ping at all. But in the dog days of summer and when towing the higher octane is needed. Performance wise, well it's ok. After installing the better heads I can now fry the tires from a dead stop. It's no street brawler, but for it's size I would say it can hold its own.

So on closing my long winded reply. Figure out your use of the car and post some more info back to us. Therefore we can give you a better idea on things.

[Austrian455]

The car won´t be used as a daily driver. Yes, it´s for my 72 Centurion. I´m going to rebuild the engine with some TA Performance stuff (Stage 1 Heads, 11:1 Pistons, 494 stroker...).
But the rebuild has to wait till next year.
Main use of the car is cruisin the city and some highway use (1 time a month).
But I want the car to have 600 - 650 Hp after the rebuild. (The car has to run mid 12´s)
At the track or some traffic light action I don´t matter about the fuel.
At normal driving I´s like to get about 11 - 12 mpg.

All the work I do my self. I also rebuild engines......
No prob.

[Austrian455]

Another Question: Did you find out something about the police permit?
That would be very kind of you, Rick.

[Smartin]

Edelbrock Performer with a Qjet...

Or even an 800+ CFM squarebore carb

[Austrian455]

What s the reason for the Performer, Adam?

[Smartin]

There aren't many guys who run the offy dual quad, and there are a lot of reports that it actually does nothing for performance gains. The Performer is a great all-around intake manifold that will accept any carb you want to put on it.

You might also consider the TA SP1 intake. It is a single plane intake that has great street manners.

[centurion 455 ragtop]

Yep, I agree with Adam on that. Regarding the permit I do have a friend that is looking into it, but gave me no definites as he thinks it is too old and the records of it may be gone. I will check back with him this coming week.

[Austrian455]

But is the Edelbrock a good choice for a 600 Hp Engine? I don´t want to sell the Offy Intake and buy another one next year.

[Smartin]

The TA SP1 is the best intake for a 600hp engine.

If you want the stigma of having a "dual quad" engine, then go for the Offy...but you're not going to gain any performance, just a pain in the butt with tuning and linkage between the two carbs.

[gashog]

I was looking at the ta catalog and it would cost me about 10 g for upgrades to my engine.
I'm thinking of spending 4g on a blower and dual carbs and get the looks for half the price of the built ta motor package.

I vote for the dual carbs.