I'm about to start a engine swap on my car and I am going to have to get a new intake/carb set up for the motor I'm transplanting. I've been a weekend mechanic all my adult life, but there is a question I have never asked that I need to know before I buy a new intake and carb.
In reading Edelbrocks web site, it seems single plane intakes make more horse's than other designs case's. And, correct me if I am mistaken, but single plane intakes are generally better suited for high RPM engines.
My question is what is the difference between a single and dual plane intake? If I understood more about single and dual plane intakes it would help a lot.
I realize the scope of this topic could get pretty technicial, but I'm just looking for a journeymans explanation.
Thanks

In a nutshell,
In a single plane, all four barrells feed all eight cylinders. A dual plane has two barrels (1-primary 1- secondary) feeding four cyls, two on either side. dual plane is better at low end torque and single will be better in the upper rpm range.

Please go to E-brock's site and pull up pic's of their RPM dual plane and Victor Jr. plane intakes and you will see the difference in them..

pdq67

single plane intakes works best at higher rpm.. In an RPM band of 3000+ rpm to 7500+ rpm

Where a dual plane will make more torque in the more used on streets RPM band of 1200+ to 6500 rpm

Don't these guys make it sound simple? They're absolutely right of course, but the problem is the blurring between true street and strip. The window of performance where either might be better is actually pretty fuzzy until SBC's hit upwards of 6500 rpms and on before every shift. At that point a single plane starts to take over. If you had a big inch SBC and a 5800 rpm peak say, either style may work better and the only real way to find out is to try them both!!!! Your 350 sounds rather pure street and as such certainly a dual plane should work best for you.

This topic is very simple. For a performance built street motor a high rise dual plane is what you want.

A single plane intake distributes the fuel more evenly at higher RPM. It has shorter runners which bring the powerband up.

A dual plane has longer runners and a split plenum.

Edelbrock rpm air-gap = the win.

Of course, pay attention to what you're doing.. I have about a half finger's width of space between the top of my drop top air cleaner and the hood, so be careful what you do there :)

I personally like the old Holley 300-36, true high-rise if there's room for it b/c it is like 1.25" taller than a stock Q-Jet intake.

I guess I like it b/c it is almost a copy of the original Z-28 intake!

To me, it just say's "SB-POWER" when I look one over AND I have a brand new one in it's box in my closet now for my next junk301 engine!!

And Summit's price is RIGHT, imho!!

It's rated at off-idle to 7,200 rpm!!

pdq67

This topic is very simple. For a performance built street motor a high rise dual plane is what you want.

Bottom line.

If you shift your small block anywhere in the 6000-6500 RPM range then what you want is one of the following.

Edelbrock Performer RPM
Edelbrock Performer RPM Air Gap
Weiand Stealth
Weiand Strealth Air Strike
Dart Kool Can
World Products Sportsman Daul Plane
Brodix HV1016
Holley Street Dominator 300-36 (Represent PDQ-Yo :p )

If you have a mild performance engine that you shift lower than 6000 then you need an intake like the Edelbrock Performer or the Weiand Action+.

It used to be that everyone with a street/strip engine ran a Edelbrock Victor JR, Weiand Team G or some similar single plane intake.

The modern day dual plane intake is truly a strong piece.It has earned it's way into countless vehicles through testing and constant improvement by manufacturers.Not to mention gearheads doing back to back tests and comparisons.The torque they add in the lower and mid rpm ranges can't be beat and the HP they develope in the higher rpm ranges described isn't far behind the single plane intake.Most of the time when someone tries a new dual plane after they had been running a small single plane they don't go back.

I shift at around 6,200 to 6,500. I run a modified Victor Jr.. I saw gains all around from when I had the Performer RPM. I wouldn't even think of running a Performer. A moderately built, higher than stock compression 400 will tolerate one size larger intake.

My old 307 really woke up over the Performer when I put an Edelbrock Scorpion intake on it. I got one in nice condition from a friend dirt cheap, and it was a good band aid until my 307 blew up. You would be amazed how well it worked on that engine. An RPM would have been better, but with what most people tend to suggest, the Scorpion shouldn't have worked at all on a lethargic 307.

I shift at around 6,200 to 6,500. I run a modified Victor Jr.. I saw gains all around from when I had the Performer RPM.
I'm still waiting for the aftermarket to do the extended runner mod to the single plane intakes.Hell all the places that work on them do it, it's not like it's a big secret or something.

I'm still waiting for the aftermarket to do the extended runner mod to the single plane intakes.Hell all the places that work on them do it, it's not like it's a big secret or something.

A lot of them do. The Edelbrock Super Victor has extended runners. So do the Dart single plane and Brodix intakes.

A lot of them do. The Edelbrock Super Victor has extended runners. So do the Dart single plane and Brodix intakes.

Yes, and they are all the large single plane's and they don't have much of an extended runner.The ones that really need the help down low are the smaller ones that would compete with the dual planes.You know, the Victor JR. and Team G 7530.

That is why I went with my Victor Jr.. Forming the runners was hard work. You should drill small holes to help locate the epoxy. Build them out in layers instead of one big piece.

As well as I wished Weiand would step up and make a direct copy of the Vizard modified single plane and sell it worth the money..

pdq67

In case anyone was wondering about the extended runners here is a picture of a manifold that has them built in from the start. http://www.worldcastings.com/prods_pages/add_info/061040_002_keyfetrs.htm

The problem is that Edelbrock is so popular that they just go in that direction instead.Don't get me wrong I'm sure the Super Victor is a good manifold, but have you heard of anyone even rtying the World Products Motown??? I'm sure another problem is that they don't pay some magazine to do a B.S. comparisson of it on a motor either.