Howdy,

 

After some general advice. 2014 FG Mk2 XR6 Turbo, Auto.

 

My car was last tuned with 3.46 diff gears (stupid idea to change the diff ratio I know).

 

On Monday 23rd July I'm having a new diff put in with factory 2.73 ratio.

 

Question - will I need to get my car re-tuned?

 

From a time saving perspective I'm hoping not, but boost will come on way lower in the rev range than with the 3.46 gears. I estimate in Gears 1, 2 and 3 probably over 1000rpm earlier.

 

Any thoughts would be much appreciated.

I wouldn't have thought so.  Most important thing is, is the speedo reading correctly. 

Thanks.

 

I'm having the axel ratio changed in some dealership level tool.

Why are you changing the diff ratio back? I'm guessing ZF auto?

Correct, 3.46 with the ZF was horrible to drive.

Oh ok, I was just curious as I've got a BF with the ZF and changed mine to 3.46 LSD. What didn't you like about it?

1st would be crap, but the rest should be ok. that's unless you have big power, then it would just be wheel spin.

1st is crap anyway haha

1-4th were crap.

 

400kwish

Well there you go. 

 

Its goes the more power you have the higher the ratio you need .  So with 500rwkw, I could go from 3.73 to 3.46 or 2.73.

 

Going the other way just makes wheel spin. BUT if you have say 240rwkw then going from 3.46 to 3.73 would give better acceleration.