TNTRacing - XRCosworth

[pablo]

We had a couple of guests with us at Oulton Park. Jap-Slapper and his lad James. Was really great to finally meet you and I don't think I've ever been asked so many questions about the car, was really good talking to you and I hope you enjoyed the day even though we broke the car

[jap.slapper]

It was a good day out for us mate thanks. James loves motorsport so for him to have the opportunity to get up close to some interesting track builds and see what's going on really got him excited.

With regards to you guys breaking the box, well as I said that's just part and parcel of the game isn't it. Shit breaks, it's a pain in the butt however I'm sure you'll find a way to get it running for the next round even if it means turning the boost right down and running with the spare box. Maybe that way having set safe alright'ish laps during qualifying and the final, go all out on the last run of the day (and if you have to get towed back to the pits again, such is life).

If you don't run you're guaranteed zero points, however if you do run on low boost/stock box and bag second then you at least have a fighting chance with those points in the bag heading into the final round as there's always the chance that your closest competitor will fail to make the final round through mechanical issue/scrutineering discrepancy etc.

[pablo]

Time to get things moving with the gearbox. The plan is..

1. Get the spare box stripped down
2 Have internals shot peened
3. Have internals cryo'd

Whilst going through everything with Alan we realised that we still had the original 29yr old gearbox mount on the car. So that's being changed for a poly one to match the engine mounts.

[jap.slapper]

How is it coming along?

[pablo]

Slowly but surely. The gearbox has now been stripped down, shot peened and is away being Cryo'd as we speak. It should be back with the gearbox company either Thursday or Friday this week to be rebuilt. Then it's another couple of days before we get it back.

[jap.slapper]

Is there anything else that can be done to increase the robustness of the gearbox?
Alternately are there any other cheap OEM boxes that can be used with that engine in the future?
I presume 3rd is the achilles heel due to the way it engages

[pablo]

This is it fo0r the standard oem gearbox and yes 3rd is the weak link. There is no other oem box that we can use. The options from here are either a skyline box conversion which Alan knows more about than me or we go to a big toothed gear kit of which there are several options. These start from around £1500.

[Monster]

Well if you need a skyline box I know a man with a good one Pabs

Guessing 3rd is the weak point as it's where it gets a long slug of torque. Seem to recall ron at RK saying the position of that gear in the box also made it vulnerable, something about being furthest away so more potential for movement but I might be making that up as gearboxes confuse the fook out me

[pablo]

It's something that me and Alan really need to sit down and sort out soon. The skyline conversion is something that we could not do ourselves as there is a fair bit of fabrication work to be done, but is defo one of the better options. We're sat ready to up the power to near 500 but I have concerns over the box so will probably do a 2 stage upgrade.

[jap.slapper]

Out of curiosity have you got a transmission temp sensor fitted? I've been looking at transmission coolers (for autos) and trying to determine whether fitting one to a manual box would be beneficial.
The general consensus being no due to auto box fluid being of thinner consistency and being subjected to increased heat under load (towing etc.) by the torque converter where as the manual fluid, being thicker and not being heated by a torque converter generally maintains a lower temp and remains thicker.
The exception being where the vehicle was being used for arduous competition conditions in extreme environments (desert rallies) where the temps were really high even when not under load.

The benefits in this case was immediately noticeable. A thinner fluid was required to enable an auxiliary pump to push the fluid through an externally mounted cooler/radiator.

I think this was also a consideration under non extreme conditions, the fluid used as standard in manual boxes is generally too thick to be pumped through and would potentially be cooled below optimum temp.

I suppose what I'm thinking is that maybe your gearbox temps need to be monitored on track so as to avoid putting it under load when the fluid is not up to temp (out lap) and/or putting under load when it is too hot.

Is there currently sufficient cooling effect from air moving around the gearbox case in the cars current form or does the front bumper and splitter setup deprive the cooling effect in favour of some front aero?