R34gtr Front Diff Changeover

[poolheaters]

Hi All

We have just purchased an R33 GTR Vspec race car that has had a new engine fitted a couple of years ago but never run. While getting everything sorted we noticed the engine was fitted with a brand new sump/front diff. Thought we better check further and found the front diff is R34GTR and 3.54:1 ratio, no good with the 4.1:1 rear.

We now need to change the front diff urgently, the car has to leave for interstate competition in a week.

Can this be done in the car without pulling the engine out?

Is it easier to drop out the front subframe and change the whole sump assembly?

Are both R33 and R34 front diffs R160 type (ie: can I use the same housing)?

And finally can anyone recommend someone in Brisbane experienced to do this?

Thanks in advance for your help.

Paul

[blind_elk]

Which I D I O T set that up?

It should be possible to do the swap without removing the engine or the sump. A hoist will help.

[Swiper the Fox]

its a 1.5hr job for an experienced operator.

thats what it took to do mine in the car.

but its a 32

[Duncan]

the ratio is determined by the pinion, all of the f160 have the same teeth on the crown. so you can't just change the centre.

Like Paul said a diff shop can do it in a couple of hours. we just change the whole sump/diff but that is when the engine is already out. they are interchangeable between 32/33/34.

very glad you checked the ratio - good choice. What is the event you are heading to, Targa Tas? If so there is a long thread in the motorsport section with all of the targa competitors.

[poolheaters]

the ratio is determined by the pinion, all of the f160 have the same teeth on the crown. so you can't just change the centre.

Like Paul said a diff shop can do it in a couple of hours. we just change the whole sump/diff but that is when the engine is already out. they are interchangeable between 32/33/34.

very glad you checked the ratio - good choice. What is the event you are heading to, Targa Tas? If so there is a long thread in the motorsport section with all of the targa competitors.

Thanks for the info so far all. And yes, heading off to Targa if we can get this thing fixed in time...

Story of the entry here http://www.tarmac-mag.com.au/news_detail.php?newsid=115

I also thought changing the whole sump may be easier, but do not want to take the engine out so maybe just doing the diff will be the better option? Either that or try and do the whole sump etc by dropping out the crossmember?

Both crown wheel & pinions are different, R33 is 37/9 and R34 is 39/11

I'll be making many calls in the morning to see who might be able to do it in time..

[tangomatt]

Hi Paul

I hope that everything worked out well for you in the end. This thread caught my attention because I did a search for 'front diff'. I am after a R34 GTR front diff and sump. I was wondering if you had swapped the 34 one back to a 33, would you then have the 34 front diff and sump assembly lying about for sale? If so, I am in urgent need of a R34 GTR sump, diff assembly.

Cheers

Matt

[Duncan]

if he doesnt....i do. what do you need? diff gear, diff centre and/or sump