DragRaceResults.Com    Bracket Talk    Bracket Talk Forum  Hop To Forum Categories  Tech Talk - by Abruzzi    mechanical pump underdrive
Go
New
Find
Notify
Tools
Reply
  
mechanical pump underdrive
 Login/Join
 
DRR Top Comp
Picture of wideopen231
posted
Wondering if anyone on site has run a mechanical pump with an underdrive. If so results, how much change in flow vs speed and thoughts on it? I guess an overdrive would affect the same but the other side of the coin so to speak so input welcome too.




America home of free. Brought to you by 2nd amendment.
 
Posts: 4479 | Location: Greensboro NC | Registered: May 24, 2011Reply With QuoteReport This Post
DRR Sportsman
Picture of Dave Koehler
posted Hide Post
I will probably regret this but why?


Dave Koehler - Koehler Injection - http://www.koehlerinjection.com
Fuel Injection - Nitrous Charger - Nitrous Master Software - Balancing
99% of fuel injection problems are electric.
 
Posts: 361 | Location: Urbana, IL 61802 | Registered: December 03, 2003Reply With QuoteReport This Post
DRR Top Comp
Picture of wideopen231
posted Hide Post
quote:
Originally posted by Dave Koehler:
I will probably regret this but why?


Not sure what to regret? I was just wondering about a pump I have that is little bigger than need and if underdriving it some with drive I have would get it closer on flow instead of bypassing twice as much fuel as going to engine.

I have some old flow numbers from Ralph that show flows on few pumps with straight up drive and then under or over. Only 3 or 4 pumps have comparison numbers. Most seem to linear change. Just researching idea some as to what to expect if I decide to try.




America home of free. Brought to you by 2nd amendment.
 
Posts: 4479 | Location: Greensboro NC | Registered: May 24, 2011Reply With QuoteReport This Post
DRR Sportsman
Picture of Dave Koehler
posted Hide Post
Linear they are, give or take. 10% equals 10%.


Dave Koehler - Koehler Injection - http://www.koehlerinjection.com
Fuel Injection - Nitrous Charger - Nitrous Master Software - Balancing
99% of fuel injection problems are electric.
 
Posts: 361 | Location: Urbana, IL 61802 | Registered: December 03, 2003Reply With QuoteReport This Post
DRR Top Comp
Picture of wideopen231
posted Hide Post
Thanks




America home of free. Brought to you by 2nd amendment.
 
Posts: 4479 | Location: Greensboro NC | Registered: May 24, 2011Reply With QuoteReport This Post
DRR Pro
Picture of Alaskaracer
posted Hide Post
My Ron's pump is driven at 1/2 engine speed....but it's a different system than what you're running...


Mark Goulette
Owner/Driver of the Livin' The Dream Racing dragster
www.livinthedreamracing.com
"Speed kills but it's better than going slow!"
Authorized Amsoil Retailer
 
Posts: 1525 | Location: Back home in Alaska! | Registered: February 13, 2011Reply With QuoteReport This Post
DRR Top Comp
Picture of wideopen231
posted Hide Post
you mean same speed as cam? Which is normal speed for pump. Asking baout lower than normal spped to reduce pump output.

Have a larger than need pump and figure if get required size at lower rpm has to better for pump life too.

As dave said it runs linear for speed and flow.10% under will give 10% less flow. WHich is what I was thinking and just dbl checking.




America home of free. Brought to you by 2nd amendment.
 
Posts: 4479 | Location: Greensboro NC | Registered: May 24, 2011Reply With QuoteReport This Post



DRR Top Comp
Picture of Curly1
posted Hide Post
Most all pumps for MFI that I know of run half crank speed whether they run off cam (1/2 cranks speed) or pulleys off crank.


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
 
Posts: 4246 | Location: United States of Texas | Registered: April 02, 2011Reply With QuoteReport This Post
DRR Top Comp
Picture of wideopen231
posted Hide Post
Best thing about belt drive pump speed simple and cheap if you want to chnnge it.New pulley or pulley and belt.Lot cheaper than the drives from waterman that I am guessing were for fuel guys back in tha day,,Mine cam out of fuel funny parts inventory. Probably what caused me to think about this deal. Hate parts just sitting there wanting to be used.LOL Yea I know whole damn car doing that most of the time.




America home of free. Brought to you by 2nd amendment.
 
Posts: 4479 | Location: Greensboro NC | Registered: May 24, 2011Reply With QuoteReport This Post
  Powered by Social Strata  
 

DragRaceResults.Com    Bracket Talk    Bracket Talk Forum  Hop To Forum Categories  Tech Talk - by Abruzzi    mechanical pump underdrive

© DragRaceResults.com 2024