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Result Of Changing R33 Diff Ratio

buzzboy
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buzzboy Enthusiast

buzzboy

Posted
Posted

Hi all

a few weeks ago ,I read that changing diff ratio's can make your car a lot more responsive down low - my goal is to have a very responsive car – not so worried about top end power and speed . The car is only for street use

A recent thread (http://www.skylinesaustralia.com/forums/Rb25det-Mines-R34-G-t270448.html&hl=mines) suggested changing to a 4.636 but I'm thinking maybe a 4.375???.

After speaking to few people in the know they all think it will be insane to change the diff ratio as I will never get any traction in 1st and 2nd.

To give you a better idea about traction issues - currently i have bridgestone 235/40zr18 91y on the front and falken grbrs tune 2 265/35zr18 on the back with some very hard coil over suspension. Car is sitting on about 200rwkw

any advice would be excellent and comments from anyone who had made the change

thanks

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https://www.sau.com.au/forums/topic/273445-result-of-changing-r33-diff-ratio/
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Pal Veteran

Pal

Posted
Posted (edited)

im still running my auto diff ( 4.3) after i had done a manual conversion a few years ago. slowly modded my car up to just over 230rwkw and not really having traction problems in a straight line. put it off balance (going around corners) and you got a bit of a problem. its still up to your right foot. if you dont want to spin, dont put you foot down. personally i think it would be a waste of time and was thinking of putting a manual diff in. my speedo is 9 km to fast at 100 km/h and putting on about 250rpm on where a manual would be. have run down the quarter mile and always have problems getting off the line, where as my fellow skyliners with there manual diffs get off so much cleaner. hope this helps

Edited by Pal
Birds Grand Master

Birds

Posted
Posted

It's always a compromise between responsiveness and traction. I say short ratios are best left to auto cars being run down the strip. I would only put a short ratio diff in a manual street car if it had no guts at all and I wanted a cheap way to get it off the line quickly. Your fuel economy will suffer and the frequent gear changes will also annoy you. Better off opting for more power/torque and you'll soon be at the limits of your current diff's ratio / your tyres, as far as traction goes.

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