QUESTION
I have heard you offer a high volume oil pump for the 907 series motor.
Do you have any further specs that you could offer on that?
I inadvertently scratched the bore that the oil pump shaft resides in.
I have been driving myself a bit nuts going over my fluid dynamics textbooks to try and figure out if the scratches will make a significant difference on pump performance.
J.H. - USA
ANSWER
Unfortunately Lotus Marques does not offer a 907 high volume pump
Several years ago a turbo Esprit was sent to us from a Melbourne Ferrari specialist who failed to correctly diagnose an excessive oil pressure problem
This problem was solved by Lotus Marques building a simple test rig to investigate the 907/910 oil pump characteristics
This not only diagnosed a faulty pressure relief valve but also provide a comprehensive understanding of the flow characteristics
As a matter of interest the internal pump components 907, 911, 910, 912 are identical and I suggest are more than adequate for all applications
If you have very minor surfaces scratches I would suggest this would have a negligible affect on pump pressure/performance
I say this as over the years we have seen engines running with fluctuating oil pressure and when investigated the outer annulus has been broken in several pieces
The other noticeable change has been in the clearances in the oil pump component clearances
I investigated this many years ago after Lotus increased the rotor/annulus/body clearance specification
This was brought about by changing from (early) CNC internal components to sintered metallurgy
The sintered (later) components produced a distorted (slightly oval ) outer annulus
Lotus "fixed" this manufacturing problem by increasing the clearance
I wrote to the Lotus Factory expressing my concerns at the time and I am still waiting for a reply
If you have any concerns about the condition of your oil pump components then be aware the pump is the heart of the engine
There are no compromises when it comes to oil pumps so I suggest you install all new components (new rotors and annulus are available)
If the bore of the pump housing is damaged then I suggest you get it sleeved - a custom bronze bush would be a good solution
Copyright © 2021 Lotus Marques
I have heard you offer a high volume oil pump for the 907 series motor.
Do you have any further specs that you could offer on that?
I inadvertently scratched the bore that the oil pump shaft resides in.
I have been driving myself a bit nuts going over my fluid dynamics textbooks to try and figure out if the scratches will make a significant difference on pump performance.
J.H. - USA
ANSWER
Unfortunately Lotus Marques does not offer a 907 high volume pump
Several years ago a turbo Esprit was sent to us from a Melbourne Ferrari specialist who failed to correctly diagnose an excessive oil pressure problem
This problem was solved by Lotus Marques building a simple test rig to investigate the 907/910 oil pump characteristics
This not only diagnosed a faulty pressure relief valve but also provide a comprehensive understanding of the flow characteristics
As a matter of interest the internal pump components 907, 911, 910, 912 are identical and I suggest are more than adequate for all applications
If you have very minor surfaces scratches I would suggest this would have a negligible affect on pump pressure/performance
I say this as over the years we have seen engines running with fluctuating oil pressure and when investigated the outer annulus has been broken in several pieces
The other noticeable change has been in the clearances in the oil pump component clearances
I investigated this many years ago after Lotus increased the rotor/annulus/body clearance specification
This was brought about by changing from (early) CNC internal components to sintered metallurgy
The sintered (later) components produced a distorted (slightly oval ) outer annulus
Lotus "fixed" this manufacturing problem by increasing the clearance
I wrote to the Lotus Factory expressing my concerns at the time and I am still waiting for a reply
If you have any concerns about the condition of your oil pump components then be aware the pump is the heart of the engine
There are no compromises when it comes to oil pumps so I suggest you install all new components (new rotors and annulus are available)
If the bore of the pump housing is damaged then I suggest you get it sleeved - a custom bronze bush would be a good solution
Copyright © 2021 Lotus Marques
