|
01-22-2022, 09:17 PM | #21 | |
Senior Member
Join Date: Apr 2020
Location: Phila, PA
Posts: 619
Likes: 0
Liked 556 Times in 293 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
Quote:
Just a rough guess. Around 12.5 HP. Let me revise that to around 9.4 HP. Stan Last edited by Stan Weiss; 01-22-2022 at 09:28 PM. |
|
01-22-2022, 10:32 PM | #22 |
VIP Member
Join Date: Nov 2001
Location: The Lowcountry.
Posts: 2,661
Likes: 2,168
Liked 2,150 Times in 784 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
I'm not attempting to doubt Stan's calculation but if we average it through the spectrum of the most commonly used combinations it's going to be roughly 10.0.
So of course based on the original question on flow of the intake and efficiency of the reversion on the exhaust side and based on a 88% + cylinder seal I believe you better have your ducks in a row to compete with the big dogs. One of the keys is chassis efficiency for sure. If you can't run with big dogs, don't stay on the porch, find out why, it's not always $$$, it's dedication. |
Liked |
01-23-2022, 09:10 AM | #23 |
VIP Member
Join Date: Nov 2002
Location: Massapequa Park,NY
Posts: 1,212
Likes: 1,744
Liked 825 Times in 267 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
How did you come up with that number ?
__________________
1989 Camaro Iroc-Z I/SA B&B Auto Machine Shop. |
01-23-2022, 10:12 AM | #24 |
Live Reporter
Join Date: Oct 2004
Location: Hickory, Ky
Posts: 10,314
Likes: 1,669
Liked 9,550 Times in 1,982 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
You want to manage the air on the outside of the car as well. Case in point on the truck the bed was off to one side. We centered the bed behind the cab and it picked up a little in et and MPH. An easy way to cheat is to cheat the wind.
|
Liked |
01-23-2022, 11:20 AM | #25 |
Senior Member
Join Date: Apr 2020
Location: Phila, PA
Posts: 619
Likes: 0
Liked 556 Times in 293 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
I ran some 1/4 mile drag simulations. After I ran the first one I realized I had used to fast of a car and reran it. Both my numbers are still only guesses. It is possible Frank's number is correct. This number will vary based on the class with A/S being greater than U/S. What is the weight of the car and what does it run for both et and MPH? Stan |
01-23-2022, 11:24 AM | #26 | |
Senior Member
Join Date: Apr 2020
Location: Phila, PA
Posts: 619
Likes: 0
Liked 556 Times in 293 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
Quote:
Yes anything you can do to reduce Frontal Area or Coefficient of Drag (CD) will show up in reduced et and increased MPH. Stan |
|
01-23-2022, 01:36 PM | #27 |
Senior Member
Join Date: Dec 2001
Location: Elysburg, Pa
Posts: 696
Likes: 285
Liked 242 Times in 94 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
I have Chrysler's old formulas and graphs and I made my own with the info that I had back in the early 90s when I had my first machine shop. I'll scan them if I can find them but I seem to remember at 3,300 lbs a 12.20 et is about 10 hp per tenth, a 9.80 at the same weight is almost 17 hp per tenth. I broke it down from 9.50 to 16.0 and different weights can be used, a heavier car at the same et will require more hp per tenth.
|
Liked |
01-23-2022, 01:51 PM | #28 |
VIP Member
Join Date: Feb 2003
Location: Glendale, Arizona
Posts: 2,991
Likes: 693
Liked 1,457 Times in 543 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
In the 1980's when I was involved with IMSA and SCCA road racing with the Mazda Factory Team, we were applying an industrial spray-on wax to the car paint finish that was manufactured by either Dow or DuPont, called Microfill. The intent of the wax was to fill the microporosity of the paint, enhancing the airflow over the body surface of the car. As I was told at the time, Mazda had discovered some aero improvement in the wind tunnel by applying the wax. At the time, the cars were being painted with DuPont Imron Epoxy Paint.
Nowadays, there are many products that contain nanoparticles with a ceramic compound that may do the same. |
Liked |
01-23-2022, 02:14 PM | #29 |
Veteran Member
Join Date: Mar 2002
Location: Miles From Nowhere
Posts: 7,471
Likes: 2,645
Liked 4,566 Times in 1,730 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
So, lacquer primer...not so good, huh? :-(
( I was going to comment on the subject of this thread, but I don't want to stink it up, so I'll start a new one..Meanwhile, I've got to go and buff out my car for next weekend;-) )
__________________
We are lucky we don't get as much Government as we pay for..... Will Rogers |
Liked |
01-23-2022, 02:45 PM | #30 |
Senior Member
Join Date: Apr 2020
Location: Phila, PA
Posts: 619
Likes: 0
Liked 556 Times in 293 Posts
|
Re: Cylinder head flow - What is crucial in a stocker?
Remember aerodynamic drag HP loss is not linear. This graph shows what a change from 0.35 to 0.34 for CD does.
Stan Last edited by Stan Weiss; 01-23-2022 at 02:53 PM. |
|
|