7525 edelbrock rpm dual quad air flow.

[Little Mouse]

Has anyone tested this manifold to see how much air it can flow my guess might be 245 to 260 cfm. Can a dual plane like this have the runners opened up to flow more air. Heads i would like to buy could be in the 280 to 300 range. Who would be good to contact to increase its airflow.

[mag2555]

Let me ask you how much hp your looking to make, not much how much flow your looking for?
500 + hp in stock form can be had from that Intake I know for a fact.

[Little Mouse]

Would like to build a 377 use at least a competition port afr 195 or 210. Want it to make good power to 7500 rpm witbout the intake manifold being a restriction. Want to use two 1 inch spacers to increase the plenuim size use 600 edelbrocks. Yes it would be more expensive to go this rout but im willing to spend the money.

[mag2555]

So want to not have the power nose over until 7500, or your shifting there?

[Little Mouse]

Want it make power to 7500 shift around 7800.

[Frankshaft]

Want it make power to 7500 shift around 7800.

It won't. Neither head will support a 7500 rpm peak power rpm. That intake will be done WAAY before that.

[F-BIRD'88]

Use the larger 750cfm edelbrocks. It will make more power.
The intake is no problem especially when carb spacers are used.
But do not chince on then carb(s) size. Bigger is better.

[F-BIRD'88]

You'll want a BIG BIG duration solid roller cam to make power upstairs, for a usable "7500 rpm" redline. Plenty compression to go with it.
1-3/4 to 1-7/8 step headers.
There is difference between "power peak" rpm and usable red line where you buzz it a bit past the power peak rpm.
Thats called "AFTER POWER"... Done by generous cam duration, big carbs, big headers.
The 500's and 600's are for the streetcruisers. if you want rpm and power let it EAT.

[F-BIRD'88]

Do not carve out that plenum divider. Just use carb spacers to get more top end . Can be combo and or open or a combo of.
Pretend its a Big Block. Feed it to go fast.

[F-BIRD'88]

Is this motor going to be run on Racing Gas? This is a BIG plus to your success of wanting a high rev'er, as the higher compression ratio really helps the BIG BIG racing camshaft. 12 to 14 :1 compression 270-285 ish duration @.050" cam. You will need a racing torque converter and correct higher ratio gears to make full use of the extended powerband.... Like a SuperStocker.
Don't worry about the manifold and use the 2x750 carbs on it.

[randy331]

The intake is no problem especially when carb spacers are used.

No problem at all, as long as you don't mind giving up a pile of power.

Randy

[F-BIRD'88]

Before you run off buying S*&^HHY. Get your head around a 406CID small block. Building a 377 is a waste of a 4.125" bore block.
Build with a 3.75" stroke crank for a 406 CID. It WILL MAKE MORE POWER and MORE TORQUE and go faster. It WILL REV JUST AS HIGH.
It is a LOT easier to get the needed high compression ratio (12:1+) with 400 pistons than 377 pistons (huge dome)
Build a 406 CID small block and use that RPM dual quad intake on it.
It will be a BETTER faster motor in every way.

[Frankshaft]

Before you run off buying S*&^HHY. Get your head around a 406CID small block. Building a 377 is a waste of a 4.125" bore block.
Build with a 3.75" stroke crank for a 406 CID. It WILL MAKE MORE POWER and MORE TORQUE and go faster. It WILL REV JUST AS HIGH.
It is a LOT easier to get the needed high compression ratio (12:1+) with 400 pistons than 377 pistons (huge dome)
Build a 406 CID small block and use that RPM dual quad intake on it.
It will be a BETTER faster motor in every way.

Regardless, it WILL NOT make peak power, and yes, he said peak at 7500, shift 7800. That intake won't get close to that. Neither head mentioned on a 377 or 406 will make peak power at 7500, regardless of how big the cam is

[F-BIRD'88]

You are missing the point. It may well make DYNO Peak horsepower at say 6700rpm BUT if build as I outline it will have very good "AFTERPOWER" where
the horsepower does not decay ( AS) much past the peak rpm. This allows you to rev it and use the FULL extended power band, reving it well past the Peak rpm point. Shifting at 7000++rpm and buzzing thru the traps at 7500++rpm.

You got a good 4.125" bore block build a high reving high compression RACING 406 CID small block.

test that intake manifold in as cast stock form (with the spacers and BIG carbs FIRST before you get big ideas on carving it all up.
You can A-B compare against a single plane or a tunnel ram with those 2x 750 carbs.
You will not give up much in real terms.

We are talking about 2 to 3 MPH in the 1/4 and a few 1/10ths +/-

Building as a 406 CID (MY combo) will more than make up the difference. It will eat a 377.

You can also build a custom DUAL 4bbl carb adapter for a single plane racing intake (Like the good Holley strip dominator) to test the 2x750 eddies on and compare against the Dual plane RPM air gap dual quad manifold ( with spacers )

[Frankshaft]

You are missing the point. It may well make DYNO Peak horsepower at say 6700rpm BUT if build as I outline it will have very good "AFTERPOWER" where
the horsepower does not decay ( AS) much past the peak rpm. This allows you to rev it and use the FULL extended power band, reving it well past the Peak rpm point. Shifting at 7000++rpm and buzzing thru the traps at 7500++rpm.

You got a good 4.125" bore block build a high reving high compression RACING 406 CID small block.

test that intake manifold in as cast stock form (with the spacers and BIG carbs FIRST before you get big ideas on carving it all up.
You can A-B compare against a single plane or a tunnel ram with those 2x 750 carbs.
You will not give up much in real terms.

But 6700 isn't 7500 for peak, with a shift point of 7800. That's what the op wants. If he is going to run 2 carbs, run a real tunnel ram. Yes, he will give up a bunch. A real tunnel ram vs the car show intake, will be 70+ hp I would bet.