Gearbox Cooling

The Oily Bits S1 Specific Topics
1

Has anyone experience with gearbox cooling of Exige S1?

  • where to take oil
  • where to reenter oil
  • which oil pump
  • which filter
  • oil-air or oil-water whats best?

We have a Honda 6-speed JDM gearbox with Cusco LSD 1,5.

2

I have always monitored gearbox temps and it is interesting how some gearboxes get hot and others dont. All of the gearboxes I had on my K series engine (standard and close ratio PG1’s and Quaife 6 speed sequential) got very very hot. I have seen over 150 degrees after only a few track sessions.

However the audi gearbox that has to handle over twice as much power stays stable at about 86 degrees.

On my K series gearboxes I actually had the caseing drilled, so I took the oil out at the bottom and sprayed it back in so it shot directly on the main shaft gears. But the easiest it to take it out of the drain hole and spray it back in the fill hole.

I used a small oil / water laminova and a small oil pump, that unfortunatly are no longer available. The oil pump i used had a strainer on the intake side and that was the only filter i had in the system, and it worked fine.

I had to have the cooler running all of the time and that kept the temperature at about 110 degrees.

The other advantage is you have more oil in the system as your cooler and pipework wil add an extra half litre or so.

Sean…

3

Just to add to this Sean and John are just about to do a laminova based oil cooler solution for me on my Toyota gearbox with a new pump from the USA so watch this space to see how it goes.

4

I have always run a similar set up to what Sean has already mentioned on my PG1, though with an oil to air cooler instead. I used the Mocal pump with -6 lines. I think one major thing to remember is to have a temperature switch in there somewhere as without it if you try to pump cold oil you just end up pressurising the gearbox, and if the standard breather cannot deal with it and you will push oil out of any available seal.

5

Good shout on the temperature related switch. I normally just switched mine on after a few laps. The Quaife box did have a seperate breather and catch tank system though.

6

Hi Sean

very short and kompetent answer.
due to the 1,5 lsd i expect temperatures over 100�
sometime i have the feeling, that gearswitch gets unprecise with evry racelap.
With the big pro-alloy cooler and the mugen thermostat we could lower the engine temps from 90� to 80� C and oil temps by 10� from 130� to 120�. Every little helps. To be honest i hope to lower tems of the inner tripods, that are a well known weak point of the Honda conversions.

I will put a seperate temp-sensor on the gearbox and datalog it at Magny Cours next week.

Peter