5L running like a bag of willies

[Immortality]

The banana manifold was designed to suit the low rpm engine, it works reasonably well for what it is, it has small long runners for that low down torque that Holden then killed with weak ass tune.

I don't see the need to have a flat boost curve, that is wasting boost/power. The faster a engine spins the more air it can handle, why limit that boost unless you are trying to make the engine have a torque/power curve like a NA engine. No one ever wants less power.....

 

[shane_3800]

The banana manifold was designed to suit the low rpm engine, it works reasonably well for what it is, it has small long runners for that low down torque that Holden then killed with weak ass tune.

I don't see the need to have a flat boost curve, that is wasting boost/power. The faster a engine spins the more air it can handle, why limit that boost unless you are trying to make the engine have a torque/power curve like a NA engine. No one ever wants less power.....

Yea, but think if you have a higher flowing manifold, you will have more low end and more top end with a flattish boost curve, giving a nice dyno curve.

 

[Immortality]

Low end is normally dictated by how much cylinder pressure the engine can handle, to much boost at low rpm causes excessive cylinder pressure and breaks **** and no one wants that where as a n/a style power curve on a boosted engine is also a waste, keep adding in boost and making more power until you reach peak rpm. Making a nice dyno graph is a waste of time unless that is how you make your money on youtube.

An expert on boost talking about boost curves and dyno graphs (time stamped)

 

[shane_3800]

Low end is normally dictated by how much cylinder pressure the engine can handle, to much boost at low rpm causes excessive cylinder pressure and breaks **** and no one wants that where as a n/a style power curve on a boosted engine is also a waste, keep adding in boost and making more power until you reach peak rpm. Making a nice dyno graph is a waste of time unless that is how you make your money on youtube.

An expert on boost talking about boost curves and dyno graphs (time stamped)

Yea but how can you argue a more restrictive manifold is better?
Even if low down boost was an issue, there are many ways to overcome that.
First would be to use a bigger pulley, then bleed less pressure off at the top, still you will have less restriction so the outcome will be more power.
Or you could tune the spark down low which would be bad because you will loose power.
Or you could use an electric controller to bleed off pressure there which would waste power and make the blower really inefficient.

No matter how many videos you post about high end drag engines which are a totally different beast, you can't tell me more restriction is going to make more power.
If that was the case then in racing everyone would be using restriction plates to gain more power.

 

[Immortality]

Where in my previous post did I mention anything about a restrictive intake manifold? Or a more restrictive manifold is better? You are trying to argue two different points. A boosted motor is a different beast to na and want different manifolds. Low rpm boost is not dictated by manifold flow, it comes down to your choice of boost adder and how you control it within the limits of what the long block will withstand. You don't run big boost at low rpm because that is how you break engine parts.

You said a flat boost curve gives a nice dyno graph, I said a nice dyno graph means nothing, you make as much power as you can with what you have. I posted the earlier video to show that you can make the boost curve/power curve suit your needs, the engine in question is irrelative.

The banana manifold is great for the stock 304, sure we could put a "less restrictive" manifold on it, lets say we put a TP single plain manifold on a otherwise stock 304 what will happen? It'll run like a total dog because the manifold is completely wrong for the engine even though it's less restrictive, the runners are way to big and short to work with the stock cam and compression and it'll be crap everywhere.

Restrictive is relative.

 

[shane_3800]

Where in my previous post did I mention anything about a restrictive intake manifold? Or a more restrictive manifold is better? You are trying to argue two different points. A boosted motor is a different beast to na and want different manifolds. Low rpm boost is not dictated by manifold flow, it comes down to your choice of boost adder and how you control it within the limits of what the long block will withstand. You don't run big boost at low rpm because that is how you break engine parts.

You said a flat boost curve gives a nice dyno graph, I said a nice dyno graph means nothing, you make as much power as you can with what you have. I posted the earlier video to show that you can make the boost curve/power curve suit your needs, the engine in question is irrelative.

The banana manifold is great for the stock 304, sure we could put a "less restrictive" manifold on it, lets say we put a TP single plain manifold on a otherwise stock 304 what will happen? It'll run like a total dog because the manifold is completely wrong for the engine even though it's less restrictive, the runners are way to big and short to work with the stock cam and compression and it'll be crap everywhere.

Restrictive is relative.

That statement about boosted engines needing different manifolds, does a few things.
It proves my point because a banana was never made on a boosted V8 VN or VS ect.
It also proves that you don't know much about manifold design.
It also shows me you don't understand engine dynamics.

All engines are boosted, N/A just means the engine is boosted by atmospheric pressure.
If you hooked up a gauge to an engine that was calibrated to absolute 0 pressure you would see that there would always be pressure in the intake.

I've said this before and I'll say it again.
If you double the pressure in the intake, as long as the fuel increases, the power will double.
This is a well knowen FACT, it has been replicated many times by many different engine builders and race teams.

There's no magic intake manifold that only works with a turbo and it won't work with N/A, if a manifold works properly for N/A it will work fine for boost.
Hence my objection to the banana because it's just poo, N/A, turbo, blower or nitrous.

 

[Immortality]

LOL.

You're full of **** as usual.

Go back to watching your hero Holdener and his perfect dyno graphs while the rest of us live in the real world.

 

[Nick Scali]

I'm sure the bananas aren't the best option for boost, but remember with a centrifugal supercharger I won't be making peak boost until 5000 RPM+

If I go a big manifold that flows more, I'll lose the benefits of the bananas down low when the centrifugal supercharger is only generating a few pounds of boost say sub 3000 RPM.

You can see in that video they took a twin throttle body manifold off a stock 304 with a centrifugal supercharger, and put the bananas back on, and it picked up a significant amount of power sub 3500 RPM over the same setup with the 'better' manifold - remember the way that supercharger does boost is its doing **** all down low, a few pounds.

I think with 8.4:1 compression (when it was new nearly 30 years ago), the unknown cam it has and the rest of it being stock, bananas are going to suit me fine with my centrifugal supercharger.

The torque power hi-rise twin would probably be better than bananas, then I need to buy the manifold plus buy a 4 barrel style throttle plate to suit it, and change the wiring for the idle control on the ECU to suit the new throttle body/plate.

It'll probably go close to 300KW/rears with bananas like the one in that video with the supercharger.

I think bananas are good when they're utilised correctly, I'm going to cost myself a few ponies up top but I'm happy to gain them down low in a compromise, without needing to spend a few thousand bucks on a manifold for a couple extra ponies up top above 5000 RPM, on a stock engine.

We're basically stock boat anchor + unknown cam + YT roller rockers + supercharger slapped on (future).

No one is arguing more restriction is better, we're arguing stock 304 + centrifugal supercharger, bananas will be good enough, or better than a big manifold (down low where you drive the car on the street)

 

[vc commodore]

I'm sure the bananas aren't the best option for boost, but remember with a centrifugal supercharger I won't be making peak boost until 5000 RPM+

If I go a big manifold that flows more, I'll lose the benefits of the bananas down low when the centrifugal supercharger is only generating a few pounds of boost say sub 3000 RPM.

You can see in that video they took a twin throttle body manifold off a stock 304 with a centrifugal supercharger, and put the bananas back on, and it picked up a significant amount of power sub 3500 RPM over the same setup with the 'better' manifold.

I think with 8.4:1 compression (when it was new nearly 30 years ago), the unknown cam it has and the rest of it being stock, bananas are going to suit me fine with my centrifugal supercharger.

The torque power hi-rise twin would probably be better than bananas, then I need to buy the manifold plus buy a 4 barrel style throttle plate to suit it, and change the wiring for the idle control on the ECU to suit the new throttle body/plate.

It'll probably go close to 300KW/rears with bananas like the one in that video with the supercharger.

I think bananas are good when they're utilised correctly, I'm going to cost myself a few ponies up top but I'm happy to gain them down low in a compromise.

The thing with @shane 3800, all his theories revolve around a motor spinning inbetween 5000 RPM and 10,000 RPM.....

He doesn't factor in a street motor that rarely sees 5000 RPM....

So if you are happy with the banana manifold and how your motor reacts with that manifold, stick with it...

 

[shane_3800]

I'm sure the bananas aren't the best option for boost, but remember with a centrifugal supercharger I won't be making peak boost until 5000 RPM+

If I go a big manifold that flows more, I'll lose the benefits of the bananas down low when the centrifugal supercharger is only generating a few pounds of boost say sub 3000 RPM.

You can see in that video they took a twin throttle body manifold off a stock 304 with a centrifugal supercharger, and put the bananas back on, and it picked up a significant amount of power sub 3500 RPM over the same setup with the 'better' manifold - remember the way that supercharger does boost is its doing **** all down low, a few pounds.

I think with 8.4:1 compression (when it was new nearly 30 years ago), the unknown cam it has and the rest of it being stock, bananas are going to suit me fine with my centrifugal supercharger.

The torque power hi-rise twin would probably be better than bananas, then I need to buy the manifold plus buy a 4 barrel style throttle plate to suit it, and change the wiring for the idle control on the ECU to suit the new throttle body/plate.

It'll probably go close to 300KW/rears with bananas like the one in that video with the supercharger.

I think bananas are good when they're utilised correctly, I'm going to cost myself a few ponies up top but I'm happy to gain them down low in a compromise, without needing to spend a few thousand bucks on a manifold for a couple extra ponies up top above 5000 RPM, on a stock engine.

We're basically stock boat anchor + unknown cam + YT roller rockers + supercharger slapped on (future).

No one is arguing more restriction is better, we're arguing stock 304 + centrifugal supercharger, bananas will be good enough, or better than a big manifold (down low where you drive the car on the street)

Yea I get all that, ultimately it is your car.
But like I said you can put a smaller pulley on and bleed a bit of boost up high, this is good for the street because you're not always at WOT 5000rpm plus.

The test you reference didn't change pulleys to account for the low end loss.

And I disagree with your last point, the dual plane should near on make the same torque down low with more cross section.