Port Energy Anomoly?

[digger]

Video 1 neither head is backing up in flow.

The flow drops sharply at 0.720” ?

[HQM383]

Video 1 neither head is backing up in flow.

The flow drops sharply at 0.720” ?

Sorry, yes it does. Missed that on the chart. Wasn't looking at this.

Screenshot_20240423-120900_Chrome.jpg

But does the thick blue line jump out as a lower hp producing head?

[HQM383]

No but the AFR has a smaller intake.

But by his measures the head with the smaller intake valve has the potential to move more air.

And it did at lower engine speeds.

I wonder whether it's the old flow bench doesn't pull as hard as a high revving engine causing the discrepency.

I hear what your saying but what flowbench would? Surely AFR done their due diligence to make sure this wouldn't happen, that a stock head had better hp potential.

Without knowing the ins and outs of the entire test I am dubious of the results. To be the "No BS" YouTube channel he should have spent at least an episode running through the test. What are the goals? What are the variables? What are the constants? How will the test be carried out? How will the data be collected? The list goes on.

Then there is lacking explanation as to why this head will only perform better than stock with tight lsa?

[WeingartnerRacing]

You cannot do test like this using a chassis dyno. It’s very hard to control engine temp, oil temp, trans temp, rear end test, and tire temp. All of these can make up the difference. The engine dyno is easier to control things.

I’m going to do a dyno test using stock 823 heads, afr enforcer ls3 heads( if they ever show up), promaxx small bore ls3, large bore ls3 promaxx heads, and maybe two others. Testing two cams a truck Norris and a much larger Texas speed.

[HQM383]

You cannot do test like this using a chassis dyno. It’s very hard to control engine temp, oil temp, trans temp, rear end test, and tire temp. All of these can make up the difference. The engine dyno is easier to control things.

I've seen 20hp disappear from strapping the car down harder to get more traction on the rollers.

[1980RS]

How many guys saw the HP disappear when they took off their oval port heads and swapped on a pair of Sq. Port heads on a 396 BBC back in the day.

[Chris_Hamilton]

Not saying DV did this but chassis dynos are extremely easy to manipulate. Years ago back when the Fox body Mustangs were all the rage and chassis dynos were relatively "new" there was a guy in New Jersey who had one in his Shop. He was in the Mustang magazines all the time. His business was selling and installing bolt on speed parts. Superchargers, exhausts, pulleys, etc. A friend of mine worked with this guy and said he would manipulate the dyno to show big gains to customers for every part he installed. He kept the records of each pull and would use that to help sell more parts to other customers. At this time in the Northeast and Mid Atlantic 5.0 Mustangs were all the rage with guys in their late teens and 20's, so business was booming.


Like HQM said above the main way they did it was by how hard they strapped the car down. Really hard stock, not as much after installing the part(s). No one had a clue. He made a ton of money for some years, especially considering he was a young guy in his early/mid 20's and really only knew how to take parts off and bolt them on.

[Tom68]

Unity video ties it together.
416ci
Cam is NLA BTR 239/254 .631/.610 114+3

They cut the AFR heads to 62cc, don't know if they were flowed before or after. 72cc from AFR ?

Wrong heads for that motor anyways.

[HQM383]

Unity video ties it together.
416ci
Cam is NLA BTR 239/254 .631/.610 114+3

They cut the AFR heads to 62cc, don't know if they were flowed before or after. 72cc from AFR ?

Wrong heads for that motor anyways.

Would have been good if pre dyno he said “DV thinks with the smaller intake valve the cam is wrong and won’t make as much power”. But instead he said “DV thinks 20hp more”.

[steve cowan]

Not that it means much but here is numbers by AFR,comparing flow numbers is not a great idea but they are not inflated by AFR.
my opinion is they have not achieved anything, they bolt another set of heads on the engine and it runs the same, WOW .
I have done that test more than once with same results.
I have said more than once,it does not matter what brand of AS CAST cylinder head you buy they still need work out of the box.i don't mean chasing flow I mean a smooth curve as Chad and TK have mentioned.
Will be interesting if the cam change does much at the track in the same car,rpm,gear etc.

Screenshot_20240423_181837_Chrome.jpg

[HQM383]

Richard Holdener doesn't have an opinion, he has a dyno. The 2.165/1.590-inch valve combo in this lsa test also responded favourably power wise to a 108* lsa

https://www.motortrend.com/how-to/1506- ... orsepower/

[pcnsd]

LOL

Nice first post!

Laugh all you want, it's 100% truth.

You crack me up

Troll

[hoffman900]

Not saying DV did this but chassis dynos are extremely easy to manipulate. Years ago back when the Fox body Mustangs were all the rage and chassis dynos were relatively "new" there was a guy in New Jersey who had one in his Shop. He was in the Mustang magazines all the time. His business was selling and installing bolt on speed parts. Superchargers, exhausts, pulleys, etc. A friend of mine worked with this guy and said he would manipulate the dyno to show big gains to customers for every part he installed. He kept the records of each pull and would use that to help sell more parts to other customers. At this time in the Northeast and Mid Atlantic 5.0 Mustangs were all the rage with guys in their late teens and 20's, so business was booming.


Like HQM said above the main way they did it was by how hard they strapped the car down. Really hard stock, not as much after installing the part(s). No one had a clue. He made a ton of money for some years, especially considering he was a young guy in his early/mid 20's and really only knew how to take parts off and bolt them on.

I know / have been to that (now defunct) shop a few times. We had no complaints but it was another application (not a Mustang, not bolting on parts) and he didn’t turn on the happy knob for us.

For the rest of this thread, I feel like I’m watching grown men conduct a middle school science fair project, in terms of controlling variables and understanding. Oof.

[RobZ28]

LOL

Nice first post!

Laugh all you want, it's 100% truth.

You crack me up

Not to stir the pot, but instead of criticizing other peoples efforts for an explanation, why dont you explain whats going on here? Wouldnt being useful instead of condescending be more prudent to your cause? Lets hear it.

[hoffman900]

Richard Holdener doesn't have an opinion, he has a dyno. The 2.165/1.590-inch valve combo in this lsa test also responded favourably power wise to a 108* lsa

https://www.motortrend.com/how-to/1506- ... orsepower/

It’s a wide open throttle dyno test from 3500-6500rpm, of course a tighter lobe separation is going to look good… for a street guy, they’re literally only testing just a little less than half the actual power range.

Like everyone sit back and take a look at what they’re actually measuring on the dyno.