"radiator" for gearbox

[845ste]

ciao a tutti,

I thought my gtr has perhaps need a radiator for the gearbox g52, because I use to 90% on track.

I noticed that even now if you do not have a decanter, oil goes everywhere in the engine compartment.

do you think you need a radiator?
anyone here uses it?
grazie
ste

[F.C.]

845ste said:

ciao a tutti,

I thought my gtr has perhaps need a radiator for the gearbox g52, because I use to 90% on track.

I noticed that even now if you do not have a decanter, oil goes everywhere in the engine compartment.

do you think you need a radiator?
anyone here uses it?
grazie
ste

I fitted a (I think Tilton) oil pump and small 9 row cooler mounted with a scoop to pick up air from beneath the car.
I have a thermostatic switch incorporated into to my transaxle oil temp gauge that switches on at any pre-set temperature.
Is it needed?
I'd rather not find out the hard way

ETS I have a Weldon pump fitted not Tilton.

Edited by F.C. on Sunday 2nd October 01:47

[Steve_D]

I would start by purchasing an infra red temperature sensor and testing the temperature of the casing after coming off track.
In preparation for these tests paint some small areas of the casing with matt black paint as the test gun does not work well on shiny surfaces.

A quick Google search suggests a temperature of 150-175 degrees C would be normal.

Steve

[Storer]

A track day where you probably only do 20 mins in every hour should be no issue.
If you are 'racing' then you have the wrong transmission.

I have a catch tank on my G50-52 that returns to the transmission. The breather pipe goes to a small bottle with a vent that catches the tiny amount blown out of the main catch tank.


Paul

[F.C.]

Steve_D said:

I would start by purchasing an infra red temperature sensor and testing the temperature of the casing after coming off track.
In preparation for these tests paint some small areas of the casing with matt black paint as the test gun does not work well on shiny surfaces.

A quick Google search suggests a temperature of 150-175 degrees C would be normal.

Steve

I have my pump set for 165, it does chime in every now and then if driven on road for 45 minutes or more, temps drop quite quickly.

[GTR-P]

I highly recommend a transmission oil cooler if you are primarily tracking your GTR and you are using a higher horsepower engine and sticky track day tyres. Many of the Porsche race folks that are required to use the G series transaxles warn that the fatigue resistance of the gears diminishes by as much as 30% once the oil temps are in the 130-150C range. (The actual temperature of the gear itself is much higher and starts to affect the heat treatment of the material)
In my case, not running an oil cooler resulted in a spectacular 3rd gear failure. (see picture). I was using a fully rebuilt G50-52 with the usual upgrades such as the billet side plate and shift forks. I had all the provisions for an oil cooler but foolishly failed to implement it. I worked with Roger at California Motorsports to source replacement motorsport gears (2nd and 3rd gear) along with steel synchronizers and new bearings etc as required. I found that rebuilding a G50 is surprisingly easy with only 3 bolts holding the gear clusters together. (I did have to fabricate a couple of simple tools to make disassembly and reassembly easier and I purchased an inexpensive toaster oven to heat the gears so it easily fits over the splined shafts).
I sent my empty trans. case to California Motorsports where they installed their internal spray bar cooling system. This provides (cooled) pressurized oil directly to all forward gears including the ring gear via nozzles positioned at each gear. I added a Tilton pump, heat exchanger with thermostatically controlled fan and an oil filter. The hot oil pressure is about 2 bar using Mobile 1 Delvac synthetic 75W90 oil. (At the least, I recommend that an oil cooler and pump be used to provide some gear temp reductions) l
My trans. oil temps now remain at about 100C during a 20min track session on a moderately hot day. I turned the pump off in order to see what the temp would otherwise be and it climbed to 130C + before I turned the pump on again. I only need to use the pump during track days.
I also added a few pictures showing how I mounted the pump, heat exchanger and oil filter.
I hope that this helps you decide if adding an oil cooler is right for you.

[GTR-P]

[GTR-P]

[845ste]

many thanks to all for the answers.
I do track day max 30 min.
But in northern Italy very hot.

I noticed that the engine oil (with radiator but no fan) does not exceed 120/130 ° C in summer in small circuit: but temp of gear???

I thought of putting an electric pump and a small cooler, because the G52 is not predisposed for a mechanical pump.??
I think even I, who for a few hours notice, where needed far more.

nevertheless i have 75/140W gear-oil.
i have 600cv and semislick toyo.
what do you think?
thanks

Edited by 845ste on Sunday 2nd October 21:05

[GTR-P]

For engine oil temperature, I think that 130C is little too high in my opinion (I have a track tuned LS7 with the help of a company in America called Katech Performance). Oil is also a cooling medium and you have to wonder what the temperatures at the main and rod bearings are. As everything heats up, clearances also reduce a bit. In my case, I have also seen close to 130C for track day oil temperatures when running consistently hard. So far, I have replaced the older side grill mesh with the newer EVO style. It did not help very much. I then added a cooling fan for the Oil cooler. It helped bring the maximum temperatures down a little bit. What it did do is take longer for the oil temperature to reach its equilibrium point of about 125C. It also helped to reduce the oil temperature down much faster when backing off a bit and shifting at lower RPMS. My next plan is to install side scoops to direct in more air. (I currently only have the side grills installed in my GTR.) If the oil temperatures still max out in the 125C range after the side scoop installation, I will think about installing a slightly larger oil cooler.

Depending on your track, it may also be advisable to install a larger dry sump tank if one is fitted. In my case, I was seeing oil pressures drop to about 1 Bar at a particular location on the track. (I have a mechanical oil pressure gauge that reads almost instantly). A few years ago, I upgraded my Peterson tank from the Ultima supplied 2 US gal tank to Peterson’s 2.5 US gal tank. (The 2.5 US Gal tank is taller but has the same diameter).
With the larger tank, the GTR can hold about 8.8L of oil while still keeping the oil level about 30mm below the baffle plate if all of the oil is flushed out of the engine. After that upgrade, I have had no more issues with low oil pressure at that track location. (FYI, I also used an ARE dry sump pan and Katech high scavenge oil pump prior to the discovery of the issue.)
The taller sump fits in the stock location. I positioned it as high as possible while still being able to remove the oil cap. (Pictures below)

[GTR-P]

[deadscoob]

Nice looking car P

The side openings do very little, you need scoops to got good air in.

Biggest improvements with the Evo mesh is the clam top and rear ventsi imo

[V8Dom]

F.C. said:

I fitted a (I think Tilton) oil pump and small 9 row cooler mounted with a scoop to pick up air from beneath the car.
I have a thermostatic switch incorporated into to my transaxle oil temp gauge that switches on at any pre-set temperature.
Is it needed?
I'd rather not find out the hard way

ETS I have a Weldon pump fitted not Tilton.

Edited by F.C. on Sunday 2nd October 01:47

matter of interest where do you run an oil temp sensor on a g50?

[ROWDYRENAULT]

My only caveat on this would be beware of running a cooler without a thermostat. whether on the track or certainly the road, oil that is too cold will do as much or more damage as not. lee

[UltimaCH]

ROWDYRENAULT said:

My only caveat on this would be beware of running a cooler without a thermostat. whether on the track or certainly the road, oil that is too cold will do as much or more damage as not. lee

Would agree with that 100% specially if the Ultima is used on the road.

[BogBeast]

Steve_D said:

I would start by purchasing an infra red temperature sensor and testing the temperature of the casing after coming off track.
In preparation for these tests paint some small areas of the casing with matt black paint as the test gun does not work well on shiny surfaces.

A quick Google search suggests a temperature of 150-175 degrees C would be normal.

Steve

A bit more money, but I bought one of these on an Amazon Black Friday

http://www.flir.co.uk/flirone/ios-android/

Very 'illuminating' ('scuse the pun), I used already identified 2 blown double glazed windows and computer PSU that was faulty. No doubt it will be useful for when I finally finish my FI install...

It has a spot temp measure option and it is withing a couple of degrees of my IR sensor (however accurate that is..)

[845ste]

very thanks GTR-P
Today I removed oil (75/140) by the change seems mud!
very necessary to a radiator and a pump.
Now I'm looking for in italy, an electric pump with filter but diffcult to find with these characteristics: 12v
5bar
3l/min, minimum
metal gear
uninterrupted continuous functioning
in USA there is Tilton or Weldon

Edited by 845ste on Wednesday 5th October 20:36

[F.C.]

845ste said:

very thanks GTR-P
Today I removed oil (75/140) by the change seems mud!
very necessary to a radiator and a pump.
Now I'm looking for in italy, an electric pump with filter but diffcult to find with these characteristics: 12v
5bar
3l/min, minimum
metal gear
uninterrupted continuous functioning
in USA there is Tilton or Weldon

Edited by 845ste on Wednesday 5th October 20:36

I have a Weldon unit fitted and have had no problems at all for a few years now.

[deadscoob]

What sort of temps does it hold on track FC?

This is on my jobs for Christmas.

[F.C.]

deadscoob said:

What sort of temps does it hold on track FC?

This is on my jobs for Christmas.

Don't know really not been on track long enough, but seems to keep in the thermostatically controlled window around 165° allowing for hysteresis that gives a window of 165°(pump start) down to 155 ish when the pump stops. I haven't seen it climb any higher.

ETS after reading GTRP's post above I may be looking to reduce that temperature range significantly I will research further into this.

Edited by F.C. on Thursday 6th October 17:24