Jump to content


Photo
- - - - -

Too Much Of A Good Thing.


  • Please log in to reply
10 replies to this topic

#1 DeadSquare

DeadSquare

    Mini Mad

  • Members
  • PipPipPipPip
  • 203 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 07 June 2018 - 08:16 AM

Clive Trickey , the C.C.C. pagan god of mini tuning, used to recommend having the highest possible oil pressure.

 

Given that pressurising oil takes power, how much oil pressure is too little?



#2 nicklouse

nicklouse

    Moved Into The Garage

  • TMF+ Member
  • PipPipPipPipPipPipPipPipPipPipPip
  • 10,077 posts
  • Location: Not Yorkshire

Posted 07 June 2018 - 08:38 AM

ah this old nugget. much has to do with the oil used and the usage of the car.

 

pressure is made up by three things. the ability to pump. the ability of the parts to resist the pumping action and the spec of the oil.

 

that is to say on one engine you could have (numbers plucked from the sky) 70psi on a 20-50 and 40psi with a synthetic 5-40



#3 DeadSquare

DeadSquare

    Mini Mad

  • Members
  • PipPipPipPip
  • 203 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 07 June 2018 - 09:57 AM

Ponder this.  The "little end" has as much piston pressure as the "big end" but a much smaller surface area and NO oil pressure supply.



#4 Moke Spider

Moke Spider

    Crazy About Mini's

  • TMF Team
  • PipPipPipPipPipPipPipPipPipPip
  • 7,598 posts
  • Location: NSW
  • Local Club: South Australian Moke Club

Posted 07 June 2018 - 10:30 AM

Ponder this.  The "little end" has as much piston pressure as the "big end" but a much smaller surface area and NO oil pressure supply.

 

totally different kettle of fish and each doing a different job.



#5 nicklouse

nicklouse

    Moved Into The Garage

  • TMF+ Member
  • PipPipPipPipPipPipPipPipPipPipPip
  • 10,077 posts
  • Location: Not Yorkshire

Posted 07 June 2018 - 10:40 AM

Ponder this.  The "little end" has as much piston pressure as the "big end" but a much smaller surface area and NO oil pressure supply.

and that has nothing to do with your original ,and only, question.

 

ponder this then,

you could then guess that it gets all the lube it needs from getting splashed? so why do people run windage trays with no issues?

 

see above.



#6 DeadSquare

DeadSquare

    Mini Mad

  • Members
  • PipPipPipPip
  • 203 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 07 June 2018 - 11:46 AM

At the 1969 Mid Ohio CanAm, Bruce Mclaren did the last 10 or so laps with no oil pressure

 

 

Ponder this.  The "little end" has as much piston pressure as the "big end" but a much smaller surface area and NO oil pressure supply.

and that has nothing to do with your original ,and only, question.

 

ponder this then,

you could then guess that it gets all the lube it needs from getting splashed? so why do people run windage trays with no issues?

 

see above.

 

 

 

Talking of "splash",  I used to own a Marendaz that had been fitted with a 1919 2.63 Litre straight six Essex engine.

 

The big ends had "dippers" that "splashed" in the sump oil, and the block above the mains had grooves that encouraged oil to trickle down to the bearings.



#7 mini13

mini13

    Up Into Fourth

  • Members
  • PipPipPipPipPipPipPipPipPip
  • 2,967 posts

Posted 07 June 2018 - 12:18 PM

again, a totaly different situation,  what was the RPM range of the Marendaz,

 

hang on, what went in it?? 



#8 slidehammer

slidehammer

    Super Mini Mad

  • Members
  • PipPipPipPipPipPip
  • 676 posts
  • Location: Surrey
  • Local Club: LSMOC

Posted 07 June 2018 - 01:29 PM

I would say that over high oil pressure is both a waste of power (very slightly) and totally unnecessary and will promote oil leaks, Something which the A series needs no help with! I seem to remember David Vizzard having a totally different opinion on this, what you want is good consistent oil pressure. I would think around 75 psi cold and 35 psi warm at idle would be a good start point.


Edited by slidehammer, 07 June 2018 - 01:30 PM.


#9 DeadSquare

DeadSquare

    Mini Mad

  • Members
  • PipPipPipPip
  • 203 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 07 June 2018 - 01:55 PM

again, a totaly different situation,  what was the RPM range of the Marendaz,

 

hang on, what went in it?? 

 

It motored at 2,500 to 3,000 Rpm, but 4,500 to 5,000 overtaking.

 

The later Essex Terraplane was the "Jag" of the american 1930's



#10 Moke Spider

Moke Spider

    Crazy About Mini's

  • TMF Team
  • PipPipPipPipPipPipPipPipPipPip
  • 7,598 posts
  • Location: NSW
  • Local Club: South Australian Moke Club

Posted 07 June 2018 - 06:06 PM

There's some info on Oil Pressure here;-

 

http://www.theminifo...07866-oil-pump/



#11 DeadSquare

DeadSquare

    Mini Mad

  • Members
  • PipPipPipPip
  • 203 posts
  • Location: Herefordshire
  • Local Club: Herefordshire Motor Club

Posted 07 June 2018 - 07:08 PM

There's some info on Oil Pressure here;-

 

http://www.theminifo...07866-oil-pump/

 

 

Very interesting read,  thank you for directing me to it






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

Mini Spares