another which diff would be best?

[ray007]

hi all,

 

im installing a VVti TT engine and a 6 speed box in my aerotop. i was wondering if i should use the auto tt diff or the TT6 diff? ive been told that the auto tt diff would give me better acceleration but will compensate for top speed which i dont mind.

 

Another prob i have is that i have a choice of using the w58 or the v161 for the conversion. Personally ive had a TT6 and also an na-tt bpu running on a 5 speed and i much prefered the 5speed? what do guys think i should do? i will be running full bpu mods and 550cc injectors with AEM fic unit etc.

 

cheers

[Homer]

The v161 normaly uses the small casing 6spd diff. An auto TT diff would be a direct replacement but due to a shorter ratio the peak speed in each gear will be reduced but acceleration improved.

 

The v161 is has a better set of gear ratios than the v160 (IMO). The w58 and NA diff will be a potential weak point in the system so if you plan for hard use it would be best to avoid if possible.

 

I've heard a few others say they prefer the 5spd ratios to the 6spd, but from the stats they don't look like they'd be ideal if you do a lot of motorway miles.

[ray007]

The v161 normaly uses the small casing 6spd diff. An auto TT diff would be a direct replacement but due to a shorter ratio the peak speed in each gear will be reduced but acceleration improved.

 

The v161 is has a better set of gear ratios than the v160 (IMO). The w58 and NA diff will be a potential weak point in the system so if you plan for hard use it would be best to avoid if possible.

 

I've heard a few others say they prefer the 5spd ratios to the 6spd, but from the stats they don't look like they'd be ideal if you do a lot of motorway miles.

 

cheers mate your always a great help

[Terminator]

Pretty much covered above, higher ratio diff also give a better fuel economy. If you check out the gear ratio calculator in tech, you can see the result of the options. I would advise trying the sorter ratio combinations by sitting in a gear at cruising speed but in a higher gear to see if you can live with the higher rpm. on long journeys. You can check out your new cruising rpm before fitting an Auto diff, as the new level might fall at a resonant point in your exhaust system, which could make long cruises uncomfortable.

 

It really boils down to what your intend use is going to be. If you can live with the rpm, the auto diff is a very quick way to improve acceleration, you loose a little top speed, but still have enough to be invited to attend one of Her Majesty's institution for a while, if used inappropriately.

 

As said before don't build in weakness to your car by fitting the N/A based items

[ray007]

Pretty much covered above, higher ratio diff also give a better fuel economy. If you check out the gear ratio calculator in tech, you can see the result of the options. I would advise trying the sorter ratio combinations by sitting in a gear at cruising speed but in a higher gear to see if you can live with the higher rpm. on long journeys. You can check out your new cruising rpm before fitting an Auto diff, as the new level might fall at a resonant point in your exhaust system, which could make long cruises uncomfortable.

 

It really boils down to what your intend use is going to be. If you can live with the rpm, the auto diff is a very quick way to improve acceleration, you loose a little top speed, but still have enough to be invited to attend one of Her Majesty's institution for a while, if used inappropriately.

 

As said before don't build in weakness to your car by fitting the N/A based items

 

thanks mate, i think im gana go for the v161 and auto tt diff. Im after quick acceleration, cant really do much high speeds in London and i think i can live with the high revs, only down side is i have the droaning Blitz nur spec exhaust!!