James B.

iTrader: (1)

Well, it's my own Server and on only U-Verse so upload isn't so great when several people are getting larger files at once. Right click as save-as

MikeGyver

iTrader: (5)

:thumbsup:

James B.

iTrader: (1)

Ran a few more sims for you to ponder. Try not to focus on peak power - that is a highly over-rated area of any dyno chart in my opinion. It's between 1500 and 3500 RPM it will spend most its time.
The only thing changed here was the intake manifold. The "tunnel-ram high-flow" is the closest simulation to a highly-ported OEM L29 manifold.

Y2KLimited

I'm a lil more partial to the bottle on my big block....

tyoneal

==============================
James:

Thank you for you help, again!

I'll get you some pictures asap. The pulley is a 3.35 or "335" as seen on the pulley.

Does this help?

I spoke with the tuner and they said the tunes usually boost about 10 psi, on 93 Octane, and 9.0 CR.

Looking at your graphs, it doesn't really look like there is a dimes worth of difference between a dual plane and a single plane.

If this is so why all the fuss about ever making a dual plane? Is this because the boost changes the relationship for both to practically 0, as the airflow would be a given under a boosted application?

I look forward to hearing from you and anyone else.

Thanks again,

Ty

James B.

iTrader: (1)

Dual plane manifolds and their smaller split runners have two advantages in a carbureted naturally aspirated setup - the split levels even out the intake pulses through the venturis in the carburetor (carbs need airflow to create the vacuum needed to deliver the fuel), and the smaller runner volumes keep velocities high enough at low RPM to increase torque.
The boost makes the runner much less relevant. We don't have to rely on the inertial velocity of a column of air on its way past the intake valve because we can push it with boost. This is why most blower manifold have very short runner of the even have them at all.
As far as splitting evening out the intake pulses, EFI mitigates the need which is why you find intake manifold for EFI all share the design of having symmetrical runners and common plenum.

If the ProCharger is being driven by same serpentine belt as everything else then the crank pulley is 7.5". If it's being driven by a second pulley that different in diameter from the oem crank pulley I'll need that diameter too. When I get back to my desk I'll try to work up some figures for the blower.

I am a little confused by the tuner saying the pulley makes 10PSI. Centrifugal blowers have a logarithmic boost curve right up until their redline. It's like saying an engine makes 400ft/lbs. torque. It is incomplete information unless we know the RPM it's making that torque at. Similarly, need to know exactly what boost yours makes at a very specific RPM at wide open throttle. If the pulley is for 10psi, is that 10psi at 4000? 5000? 8500RPM? You can see here what's missing.

As far as changing the manifold, I still feel that is totally unnecessary even though I realize that pretty much ruins my chances for scoring an awesome multiport single plane manifold second-hand. lol

tyoneal

James:

Thanks again for writing.

[QUOTE=James B.;5319029]Dual plane manifolds and their smaller split runners have two advantages in a carbureted naturally aspirated setup - the split levels even out the intake pulses through the venturis in the carburetor (carbs need airflow to create the vacuum needed to deliver the fuel), and the smaller runner volumes keep velocities high enough at low RPM to increase torque.

The boost makes the runner much less relevant. We don't have to rely on the inertial velocity of a column of air on its way past the intake valve because we can push it with boost. This is why most blower manifold have very short runner of the even have them at all.
As far as splitting evening out the intake pulses, EFI mitigates the need which is why you find intake manifold for EFI all share the design of having symmetrical runners and common plenum.

Thank you for the follow up with this, everything makes perfect sense.

If the ProCharger is being driven by same serpentine belt as everything else then the crank pulley is 7.5". If it's being driven by a second pulley that different in diameter from the oem crank pulley I'll need that diameter too. When I get back to my desk I'll try to work up some figures for the blower.

I'll get the width of the other pulley tomorrow.

I am a little confused by the tuner saying the pulley makes 10PSI. Centrifugal blowers have a logarithmic boost curve right up until their redline. It's like saying an engine makes 400ft/lbs. torque. It is incomplete information unless we know the RPM it's making that torque at. Similarly, need to know exactly what boost yours makes at a very specific RPM at wide open throttle. If the pulley is for 10psi, is that 10psi at 4000? 5000? 8500RPM? You can see here what's missing.

Your right I gave you only half the picture. By looking at the Dyno graphs I have, I can guarantee that max psi. occurs way too high in the rpm band. It starts at 4700, and max power is at 5700, and stays flat to 6400.

I guess this information would have been much better for your information, sorry about that I just didn't think this though. I must have been tired or something.

As I think of this, my gut tells me I need a MUCH bigger Super Charger that would reach max boost (10 psi) as early as possible in the RPM of the engine. Hypothetically, a 10 psi boost ramp up to 2000 RPM or earlier, then vent the extra boost up to 5500, then hit a rev. limiter at 5700. I think the 502 can gulp down at 5500 rpm. 1100+ cfm.

I wish they made a positive displacement Super Charger with an internal intercooler. That would kick the truck in the butt "post haste!"

Is this in the ball park?

As far as changing the manifold, I still feel that is totally unnecessary even though I realize that pretty much ruins my chances for scoring an awesome multiport single plane manifold second-hand. lol

Any chance you want to score a stock efi system from a BBC out of a '97 Suburban? lol

I look forward to hearing from you.

Ty

tyoneal

James:

I have some photos if you think they would help, however I've been trying to add pictures using the tools here and have not been successful.

I will keep at it.

Ty

Y2KLimited

just to throw some interesting CFM data into the mix the 502 ramjet comes with a 48mm L98 tpi style throttle body....and looking at the way the procharger bracket mounts off of the AC that intake manifold won't even be an option I had to move the AC compressor about 2 inches outward and 1.5 inches up if I remember right (which would put the compressor on the ABS module)

A F1 headunit has a 5.0 vs 4.1 internal gear ratio which will come in earlier and the impeller is a beautiful work of art, I guess with a waste gate after the intercooler you could bleed the excess off at 10 psi, but your next problem will be the 6 rib belt, it won't be happy with the 5.0 internal ratio and getting an 8 rib setup would probably want a stronger tensioner than stock, not to mention run into a few fitment issues if I remember right (I haven't had a procharged 5.7 since about 2002 in the tahoe so I could be wrong) on yeah now I remember the major headache the AC clutch...LS cars/trucks run a seperate ac belt and don't have to tackle that headache...

James B.

iTrader: (1)

Assuming a 5800 engine RPM limit imposed by the hard ceilings in the PCM, you can safely run down to a 2.88" pulley on the blower without overspinning it. At some point belt slippage is always eventually a consideration with smaller pulleys but I think at 3" you'd be fine.
In other word, you've got plenty of room to grow with your current blower!