Yellow Bullet Forums banner

1 - 20 of 62 Posts

·
Registered
Joined
·
1,682 Posts
Thanks for the videos Steve!
 

·
Registered
Joined
·
7,855 Posts
Holy 8lb-9oz sweet baby Jesus.......

One thing would be interesting in the tubing test also is what happens when there is a 90 right off the blower outlet like most cars have. I think that alone is 1psi on mine.....

Great job guys, that thing is making some beans!!!
 

·
Registered
Joined
·
884 Posts
Thanks for the new video Steve. It will be interesting to see if the 5" tubing will do much on that motor. I know when John Urist upped his tubing from 4" to 5"on his motor, he said that he didn't see much of an improvement. Will be interesting to see none the less :cool:
 

·
H&H Racing
Joined
·
10,919 Posts
Thanks for the vids and testing you put in steve...



Am I seeing the vids right? It took a modded bigger blower to make the same as a stock smaller vortech?
 

·
MFI on CH3OH
Joined
·
14,291 Posts
Think thats what im seeing as well. Also is the vortech making better average hp across the board as well ?
 

·
X275 Derby Winner!
Joined
·
2,839 Posts
Steve,
Thanks for sharing your data, and showing us the difference between the modded vs virgin blowers.
It seems like it would be a wise investment to those combo's that are "tapped out".
Have you done the blowers mods on a Vortech yet? I would like to see that data if available.
DonB.
 

·
Registered
Joined
·
2,122 Posts
So interesting.


Can anyone explain the physics behind the manifold pressure being 2lbs less than post intercooler pressure at 5940 rpm and 5lbs less at 7686 rpm?
Also the relationship behind pre intercooler pressure being 5lbs more than post at 5940 rpm and 2lbs difference at 7686 rpm. Pre to manifold boost seems to be 7lbs across the range.

My guess is that the 90 deg turns are having differing turbulence effects at various air speeds. It makes you wonder what real world passenger seat, dash or back seat A/W tubing arrangements have on boost loss/system resistance.

I'd love Steve to do a pump gas A/W with in car style tubes against pump gas with meth injection. We might not see what we expect to see.

According to HGTVPro.com, "a 4-inch diameter dryer vent may not exceed 25 feet in total distance because of the air flow a standard dryer produces. For each 90-degree turn in the pipe, add 5 feet to the distance measured in Step 2. For each 45-degree turn in the pipe add 2 1/2 feet to the distance measured in Step 2. For example, a 10-foot run of vent pipe with two 90-degree turns is equal to 20 feet of straight pipe."

http://www.wpb-radon.com/Piping_pressure_drop.html
Total system resistance is the airflow resistance of the pipe and all of the elbows. The resistance to airflow in each elbow is typically determined in equivalent straight feet of piping. In other words a sweep 90 degree elbow might have the same resistance to airflow as six feet of straight pipe.
Note:
1) You need to know the speed of the airflow (CFM) to make this calculation.
2) Pressure drop increases with airflow
3) Pressure drop decreases if pipe size increases but airflow stays the same
4) As pipe size increases the equivalent footage of pipe fittings increases
5) Elbows with hard edge turns have more than double the pressure drop of sweep turns.


Some cars with back seat A/W coolers have 15' of pipe with several 90 deg turns. Is the colder charge worth the boost/cfm loss?
 

·
Registered
Joined
·
2,122 Posts
Steve I think I just found out why those readings are like they are.

http://www.wpb-radon.com/Measuring_airflow.html

Airflow in a pipe is not uniform. When air enters a turn (elbow) airflow is most disrupted coming out of the turn. The general rule is make airflow measurements at least 2 pipe diameters before an elbow and at least 8-10 pipe diameters after an elbow. To most accurately measure airflow in a pipe that has no airflow vanes to make the airflow more uniform you would average multiple pitot measurements using the following pattern. Not trivial as you can see.



So whilst the pressure drop blower to manifold is a contact 7lbs the pre-post measurements are skewed due to the changes in air speed/turbulance at differing parts of the tube cross section. The measurement probe is in only one location.
 

·
KEVIN CAPS LOCK
Joined
·
80,376 Posts
THANK YOU STEVE
 

·
Registered
Joined
·
3,823 Posts

·
Registered
Joined
·
10,234 Posts
Impressive. may I ask what fuel you were running and ECU processor?

question, is the 136 the newer version that is to replace the 139mm unit?
 

·
Registered
Joined
·
1,682 Posts
Thanks Jake.... You Rock... When I see ya, we're gonna lift some 12oz weights.... On me..;)
Lol... He prefers Disaronno and Dr. Pepper. :p
 
1 - 20 of 62 Posts
Top