Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

[Rick360]

I have PTS plates now then I tested them on DV's bench. I am confident my numbers are not inflated. Thanks for the offer Chad.

Thinking that two different flow benches that are "calibrated" using so-called "Calibration plates" will measure flow thru a head the same is absolutely wrong. Calibrating flowbenches in this manner, that are the same exact model, might get you within a few percent of each other. When the flowbenches are different design, you have no idea how close they will truly be.

Calibration plates can't have a Cd or a flow rating unless they are "calibrated" in a system. Then they will only flow that amount in that same system arrangement.

Rick

Rick, if you have a more accurate method to calibrate a flowbench I would be interested in the procedure. Thanks, Charlie

Put your "calibrated" plate on top of a test fixture and see what your bench says it flows compared to flat on top with no adapter. Why does it read different if the plate is "calibrated" for xxx flow at xx"wc? Shouldn't it always flow the same? Because EVERYTHING around an orifice affects the flow thru it. The size of the air box, the diameter and thickness of the hole the plate is positioned over, the distance to any other objects before and after the orifice. Therefore calibrating your bench to another bench of a different construction or design using an orifice mounted on top as is commonly done wont guarantee you anything about how they will measure heads.

One way to calibrate it properly is to have a calibrated system mounted on your bench that would normally include 2 straight pipes with a flow measurement device in the middle like an orifice, venturi or LFE. It would need some type of flow control above the adapter to adjust flow thru the system. Keep in mind with the same head that real cfm flow will vary from day-day even though the flowbench reads the same.

Since Superflow are pretty much the standard in the industry I flowed a head on a SF600 at Ron's Porting many years ago and saw the readings and the calibration sticker with my own eyes, then I flowed the head on my bench and adjusted my flow ranges to match. Does that guarantee that my bench matches the stated CFM? nope, but it gives me the best way to compare my numbers because I have no idea how close to actual CFM a SF is. When Speedtalk did the Flow-Around HEADS that my bench came in dead center of the range of benches.

Rick

[Rick360]

Don't take the bait, Chad. That guy will argue with a fence post.

I will not.

lol

Rick

[user-9274568]

How do you calibrate your bench Chad?
I have used sharp edged plates for mine but I have seen different flow results from benches calibrated with the same plates.
And usong them on top of a Superflow 600 did not work at all.

Erland

I have a few PTS plates. But I purchased a set of stainless calibrated plates that I use mostly.

I also use the Superflow formula for hole size.

As an example I have a 1.867 PTS plate marked 250cfm. I have it marked 245.4 per SF. I also have a 2.504 plate marked 450cfm. I have it marked 440.8 per SF.

I have a custom bench I built and it does not read the same as the SF. It sees the air different.

[Rick360]

Your doing it right! Just like everyone in this country. Just like Harold Bettis will tell you to do it.

Just keep following the herd.

Rick

LMFAO

So, does RON'S calibrate their bench like you do?

Superflow calibrated it, thats why I looked at the SF cal sticker myself. I was there.

Rick

[Rick360]

How do you calibrate your bench Chad?
I have used sharp edged plates for mine but I have seen different flow results from benches calibrated with the same plates.
And usong them on top of a Superflow 600 did not work at all.

Erland

Hmmmm, think about what Erland's saying here.

Rick

[user-9274568]

My calibrations for my SF are completely different than what is posted on my bench.

If a bench reads the same amount off from start to finish vs another bench, that is OK as they actually give you a % from bench to bench.

If your bench is 5 off and ends 15 off, you have problems with your bench.

[RevTheory]

Don't take the bait, Chad. That guy will argue with a fence post.

I will not.

lol

Rick

Nice

[user-9274568]

Prime example. SF600 with a Blue Box vs my PTS with a Performance Trends. The SF required a .60cd per calibration and the PTS required a .58cd per calibration. BUT, look at these curves and this is ALL that matters.

Same head, same fixture, off one bench on the other.

LIFT CD/PT
.200 137/138
.300 193/193
.400 244/242
.500 284/286
.600 317/317
.700 326/327
.800 334/338
.900 342/345
1.00 347/347

[Carnut1]

Rick, I agree the bore adapter will change the cfm. The book from superflow states remove bore adapter and mount plate directly to bench to calibrate. We should also calibrate through the swirl meter? That has to make a difference as well. Until we get a consensus I will calibrate according to Bettes and Superflow. Thanks, Charlie

[Erland Cox]

How do you calibrate your bench Chad?
I have used sharp edged plates for mine but I have seen different flow results from benches calibrated with the same plates.
And usong them on top of a Superflow 600 did not work at all.

Erland

I have a few PTS plates. But I purchased a set of stainless calibrated plates that I use mostly.

I also use the Superflow formula for hole size.

As an example I have a 1.867 PTS plate marked 250cfm. I have it marked 245.4 per SF. I also have a 2.504 plate marked 450cfm. I have it marked 440.8 per SF.

I have a custom bench I built and it does not read the same as the SF. It sees the air different.

Here is a 30+ year old drawing of my homebuilt bench.
It is a pitot bench and it is number 2 that I made after an 80:s article in Car Craft.
With the first bench I had not yet learned how to calculate the flow but with the second I had.
Here are some pictures and text i Swedish: http://www.topplocksverkstan.se/flodesbanken.html




Erland

[Rick360]

Rick, I agree the bore adapter will change the cfm. The book from superflow states remove bore adapter and mount plate directly to bench to calibrate. We should also calibrate through the swirl meter? That has to make a difference as well. Until we get a consensus I will calibrate according to Bettes and Superflow. Thanks, Charlie

That's because they know where their orifice should read on THEIR bench with it mounted there, but the orifice test is just to verify that it is working correctly. Nowhere in their manual does it say to change the ranges on THEIR bench based on an orifice you put there.

My point was that ALL of those things I mentioned DO AFFECT the flow thru an orifice. They have a 1/4" or 3/8" metal plate on top of their bench. When you have a home-built bench and it has 3/4" plywood you now have a different flow thru that "calibrated" orifice.

An orifice by itself CANNOT be calibrated to a flow.

Rick

[user-9274568]

Well, the calibration system you can rent from SuperFlow requires you to calibrate each hole. More than one plate is provided for each hole as well.

Each hole in a SF, DOES NOT see the same delta across it. Therefore each hole will and should have a different calibration. Another thing. SF used 10" of depression to calibrate from the factory.

The rotating disk in a SF bench is one of the crudest things I've seen.

[Carnut1]

Just keep following the herd.

Rick

LMFAO

So, does RON'S calibrate their bench like you do?

Superflow calibrated it, thats why I looked at the SF cal sticker myself. I was there.

Rick

Fyi superflow calibrates at 25"

[Rick360]

Fyi superflow calibrates at 25"

I think the SF300 ranges are at 25" but the SF600 is 28"

Rick

[user-9274568]

The 10" came from SF. The posted numbers are 25" on a SF300/600..

Any SF300/600 bench over 2000 is going to be different than the older units because the new Pro Benches were totally different with the same head. It was in the bench design. So SF tightened up those numbers.

The rotating disk is a sharp edge hole.