Battle of the 915 transmission coolers RSR vs Euro

[Blackbyrd]

Does any one have a flow Chart of Which 915 factory oil pump pumps the most oil ? Or oil pressure ?

I ask because I have a few 915 RSR trans spray bar kits + the 911RS version (with out cooler) and wanted to use one for my 923 (912e) transmission (don’t ask lol)

The RSR nose cone spray bar/cooler has the side fittings to go to a cooler




But would it be a better idea to use the later 84-86 euro trans cooler ?
And the 911RS spray bar kit (with out fittings for oil cooler)

Does that Euro cooler flow more than the RSR spray bar version ?

I would prefer the RSr version that I own now vs the euro one that I sold years ago an don’t own a complete one ... granted I will remove the loop accordion and add a cooler






I ask this because I want to run a oil cooler to my 923/915 Trans but, I want the cooler to go to the front of the car. The 934/911RSR ect had a trombone cooler upfront and pumped oil.

Just wondering if this will work (I’m using a very small cooler)

Did not want the cooler next to the trans or mounted to the rear of the car like I’ve seen others
Not do I want aftermarket parts.


Advice appreciated

[Matt Monson]

I wouldn’t try to run oil to a front mounted gearbox cooler without an inline electric pump.

Do you have pictures or pet diagrams of this system? I’ve never heard of it before, and quite honestly doubt that it’s required at all.

[Bill Verburg]

After a short search the only reference I have is wrt the late 915/67 RoW cooler dropping the fluid temp by 20°C and increasing the fill to 3.1L

[Blackbyrd]

You wouldn’t run one with out an electric pump (another potential fail point) but the factory sure did on several occasions.
911R 911RSR and even on the SCRS to name a few

There isn’t a PET diagram for many areas of the car specially for race cars
Maybe in a paper hand manual ? All the RSR parts manuals I’ve seen are mostly text.very few photos
Heck pet removes items when NLA or omits pages altogether.

Although I do have the SCRS parts manual and that doesn’t state the oil pressure.



A lot of the things we do to theses cars aren’t required but we still do them.


I’ve search the forum and no mention of trans oil fluid pressure, I may have to do a physical test to see what kind of oil pressure comes out of that factory 911RSR 915 mechanical oil pump.
Just trying to make sure the system is working.

The later cars ditched the oil cooler going to the front, and instead I see the cooler in the engine bay, not trying to go that route.

[faapgar]

The gears on the RSR tailcover are adequate for the internal spraybar.We used a Tilton electric pump and and ran lines to a cooler in LF fender.Used a helicopter cooler that was 8 wide x 4 high and 2 deep with schrouded air forced through.Used 2 spray points on top of box.One above gears 3 & 4.The other above R & Pinion.Fluid temp stayed around 180-190.Simple but effective.I should have aTilton and cooler.It was a Harrison cooler made in NY.Fred

[Blackbyrd]

Thank you for your input faapgar
Remember they made two versions of the spray bar kit
(Luckily I own both) #1 The RS version Just sprays inside #2 RSR sprays the inside and has fittings for an external oil cooler.

The 3rd one I do t have complete is the one also pictured above that loops the oil (84-86)

I don’t want to run a noisy, heavy pump that could be a fail point.

The factory did not run a electric pump for their mechanical transmission oil system, so was trying to stay with that route. Trying to figure out the oil pressure these pumps run at
As they clearly ran them to trombones and oil coolers.

[Bill Verburg]

As far as I can see in the SC/RS manual they ran either the same side cooler as the 915/67 or a small radiator, both used the same side cover mechanical pump

[Blackbyrd]

Yes Bill that is correct

Curious to see what the difference between oil pressure is
When it comes to the SCRS vs the nose cone (tail end) 911RSR cooler/spray bar kit

Pump
Size they don’t look that different

My other idea was just to run the spray bar kit (closed circuit non oil cooler type)
And then run the European cooler w/ an external oil cooler but that wouldn’t be the correct look for this particular car.