FRSTR90

Hey guys..

I am looking a for a Dual Quad set-up for my '73 that will fit under the stock hood. I am currently looking at Edelbrock's C-66-R Part#5421 hoping that it might fit under a stock hood as it is roughly .75 in taller than the stock manifold. However, the height of the air cleaner is roughly 3.5in from the where it sits on the carb. Is that too tall? Is anyone on the forum running dual quads under a stock hood? If you have a dual quad please share the with us what you have and the clearance that you have (even if you have an L88/High Rise hood).

Thanks..
John

vettesbydesign

John....I think that you are going to have clearance problems,bud.I don't remember seeing anyone here run a BB w/dual quads under a stock hood,but there was a guy,I THINK,who recently posted,and is running a SB w/dual quads.Try to find him,and see what type of clearance he has.
How is your father?Tell him,and your mom that we send warm wishes,and praying for your dad....all of you.
Kevin

GDaina

A member from Mass., haven't seen him post in a while, has custom painted late C3, think maybe a 79 big block and dual quads....wish I could remember his name....he also has a 67...

Mass vette or something similar...

HamadUP

I've been researching about intakes which will fit under stock BB hood for a while, I found that only two kinds of aftermarket intakes would fit, the Torker series from Edelbrock, and the street dominator from Holley (discontinued long time ago) and both were a single card, open plenum types. The only multi-carb intake that would fit is the GM tri-power.

vettesbydesign

I wonder if someone could grind the surfaces down on the carb mounting area so they were angled like the factory tri-power intakes?

63 340HP

Something to consider...

GM tested a prototype dual-quad big block intake in the late 60's that fit under the factory hood. It is a Winters foundry casting with a 0 - part number. The intake used two quadrajets on a single open plenum manifold. The front quadrajet was mounted backwards, placing the fuel inlets and all four primary venturi's in the center of the manifold and the large secondaries at the ends of the manifold (almost directly over the intake ports).

I have no idea how the throttle linkage worked, or how it performed. After looking the manifold over it would be hard to make a similar dual-plane with large enough ports to flow comparable airflow.

FRSTR90

Maybe I can find him on the forum directory?

I currently have a Torker 2-R, but I do not see the hood closing. This intake is about .25-.5 in. shorter than the Performer RPM. Maybe if I knew how tall the stock '73 air cleaner assembley is for a BB I could make some calculations and have a better idea. Maybe I can find an old street dominator?

FRSTR90

If I could have it machined down like half an inch that would be perfect, but based on the pics of the manifold. There doesn't look to be enough metal for that.

That would have been a neat little set-up! Too bad GM didn't come out with a lot of their prototype engines and stuff... From what Im told, there was a prototype DOHC Big Block. How cool would it have been to have one of those monsters sitting under the hood?

08vycpe

I know the OP is questioning the dual quad clearance for a BB in a '73. I have a SB '73 running dual quads on the original engine and things fit just fine with the stock cowl induction hood. I have the Edelbrock dual quad manifold/carbs/linkage package. The only issue I have is with the strock throttle cable which is way too long. You will need to buy and trim a lokar cable assembly.

baxsom

just to comment on a couple of posts here
the torker 2 will clear with a LT1 drop base air cleaner no problem
( i just took one off)

also the LS6 454 intake will fit under the stock hood as well but you are putting a rectangular port intake on an oval port head. (mixed opinions on this one)

FRSTR90

08vycpe,
Beautiful set up! Besides it looks like you have an extra 2-3 inches of room perhaps. I just wish I knew how much taller the flange is where the manifold rests on the block than a Small Block. That and with some calculations I could then determine whether or not I can get this to fit.

The Torker manifold I have is the Toker 2-R. I believe you are refering to the Torker II 2-O. My manifold is more like a Vic. Jr. with the carb sitting at a 45* angle from the block.

The LS6 would work well as it has rectangular ports, but the low-rise is going to greatly hurt my performance with a very expensive price tag. That is why I havent even thought about using it. I guess if I really have to, I will try to find one, but I'm not going to pay $400 for one either. That is just insane price tag for such a terrible manifold. I honestly cannot see why this manifold is so expensive. I know some are repo-ing the manifold. Which you would think bring the prices of these manifolds down, but it doesn't seem to have any affect on the market. Why people want this manifold beats me. All they are is an L88 manifold that has the runners sucken down into the oil valley. Unless you have a BB rect. port vette, I think one would be crazy to put one of these manifolds on. And, to further explain why the price is outrageous, about 95% all BB vettes I've ever seen are stock untouched originals and 99% of all vettes I've ever seen have been oval port BB! Rect. port BB in a vette is rather rare (435HP, L-88's, L-89's, LS-6s vs. the common 390HP, 400HP,LS-5's, LS-4's). One using an LS6 manifold in anything other than a vette is not very bright as you can get an Edelbrock Performer RPM manifold which is just like the L-88 manifold for half or 2/3rds of the price!

Sorry about my little rant! These LS-6 manifold prices are just ridiculous..

08vycpe

I just wish I knew how much taller the flange is where the manifold rests on the block than a Small Block.

If the engine mounts are in the same place for the BB and SB you might try measuring the height from the engine mount to the 45* mating surface on the engine block by placing a 45* block in place on the 45* angle of the engine block to manifold mating surface. (thus creating a horizontal surface to measure to.) You could then compare the same dimension on a SB to see the difference.

Or maybe you could place a piece of clay on the 45* angle block placed against the angle of the engine block/manifold surface and close the hood. Then measure the height of the compressed clay to see how much clearance you have to the hood. Put a piece of wax paper on top of the clay so it doesn't stick to the hood.

FRSTR90

Well I don't have the SB out yet... I was going to wait until I have the whole engine built, then remove the SB and put the BB in the same day. Who knows I might just take it out tomorrow for the heck of it!

Ironcross

I had considered a dual quad 427 for the street myself. I ran a crossram Edelbrock on a L72 427 in one of my drag boats. It ran very good. About the only company that has one to even consider is a newer low profile inline Edelbrock square port with a pair of 650`s using air cleaners off a 56 that are neat small aluminum types a couple of inches high.

FRSTR90

Wally,
That is actually the one I am considering.. I have an edelbrock 600 laying around. All I need is the manifold, an extra carb, new throttle linkage and cable. Tell me what are your thoughts.. Do you think it would work? If not, how about the old tarantula manifolds? Maybe I could have it machined down a half in.?

Edit: Scratch machining the manifold down idea.. Not enough metal to machine down and running the risk of damaging the manifold is really high.

Ironcross

I like quads and they work for me. no reason they wont work for you. I like the crossrams but they are too high for a Vette. I do recall in one of my catalogues there was a low dual quad intake available. Air cleaners are a problem sometimes but the tiny 56 Vette air cleaner should work that was placed on the Vette quads. I was considering a set of quads on my LS7 Camaro and my A990 Hemi Cudas engine came with the mag crossram and a pair of 770`s. I know they work...NHRA holds a Hemi Shootout with the AA/SA 68 Cudas with the same A990 engine I have and they run middle 8`s at over 150...Cant beat success,...

I may go to the Livernoise open house Sunday if I can get away and see if that in line intake is still available.....

Bowerss2

Edelbrock C26for SBC



doesnt help you much for your BBC, but i did have to fab a custom throttle cable, the stock one was way too long.

carbster09

There's a book on "hot rod" engine build ups and the guy that wrote the book had a BBC with dual quads under an L88 style hood. He was running a 496. The book was Hot Rod Engines or something similar. There are a few interesting builds. A couple of hemi's ... not that I would want to build a MOPAR, but its a neat engine.

Search amazon ..

carbster09

roscobbc

Some years back there was a series of magazine articles titled "Big Block from Hell". One of the final articles was testing out the 'then new' Edelbrock low rise dual quad with Edelbrock carbs - whilst it seemed to pick up a 'few' hp at certain revs there didn't seem to be any sigificant benefits - I fact I remember the testers actually giving up on the combination due to having difficulties in getting the carbs in tune across the whole rev range.

langg

I have the Edelbrock 2 x 4 setup on my BB 75. I went with the L88 hood for air cleaner clearance. With the oval air cleaner there is about 3/4 inch clearance at the front of the a/c. lots at the back. I have changed to cold-air intake since the avatar pic and have two 6 inch air cleaners.

One reason that I didn't try to fit everything under the stock hood was that I felt a tiny air cleaner might not effectively flow enough air to feed the 540 at moderate to high RPM.

Langg