Fu&*king Diff

[180 wanabe]

After getting dicked around for close to 2 months I finaly got my diff!

with the last sprint day of the year on 2morow I thought I would give my workshop a call and see if I could bribe them with a carton of beer to stay back and install it for me so I could try it out 2morow

well my so called drop in replacement isint quite that

I ordered a QDL10L which states it is a drop in replacement for 350Z autos with open diff. Well my V35 should be mechanicaly the same as a US spec poverty pac 350Z auto running an open diff

Anyhow I picked up the diff and went to the workshop and waited around 3 hours as they finished off a job that didint go according to plan but finished it none the less.

Now it was my turn the old diff came out everything seemed to be going to plan

The new diff centre was put into the diff housing everything bolted back in with things looking normal... and then dasiaster struck

One of the drive shafts was too long to go back in!!! IM THINKING WTF THIS IS THE DROP IN REPLACEMENT

After lots of banging and screwing around I told the guys to call it a night. One of them suggested cutting the longer drive shaft down in the morning which should do the trick

after scouring the net when I got home I came across an install guide for a G35 with a viscous diff, the guide states that the longer drive shaft needs to be cut down 1.7"

The instructions that came with the diff were minimal to say the best, basicaly just saying to install the diff as you would the OEM one

now the thing I dont get is my car has an open diff being an auto so WHY THE HELL is one drive shaft too long just like in the viscous install guide which is going to require a chop down of 1.7"

so angry

Worst of all there are no part numbers on the box that I got so I have no idea what diff I have recieved although it looks the same as the QFD10L which also looks the same as the QDD13L which is the replacement for the viscous diff

[omp]

Bloody hell mate, sounds like a lot of assing about! Hopefully it works out for you.

[jawrgy]

New to mods but how will the diff improve the cars performance?

[blk94r33]

Not experienced with V35's. But when the drive shaft is cut down:

-Where will the material be removed from? The shaft/flange assembly that goes into the diff I assume?

-How does the shaft/flange couple to the center (to stop it moving around/"falling out")? Spring loaded C-Clip? Will this be kept when it's cut down?

Sounds like a massive head-ache...

[180 wanabe]

Ok had somewhat of a win today

Got the guys to cut off the excess stub axel and get the diff in the car, the other option was to get a stub axel from a wrecked 350z "was quoted 200 wrecker in bris"

ill post a link to a complete guide on how to install the diff, mind you this is for a G35 with the viscous diff

http://www.tune2win.com/index.php/diy_tech...r_installation/

The above picture shows what needed to be cut to make it all fit

Anyhow after everything that went on over the last 24 hours I managed to throw on my race rims/tyres and make it to QR @ 2:30, just to kick sand in my face the rain started to piss down on the way. Fortunately my Toyo R888s are still fairly new and had plenty of depth in the grooves so I didint end up aquaplaning the whole way there.

The track day was 1/2 over but I still managed to get 2 sessions out on the track before the end of the day

On the 1st session the track was 80% dry however I didint go all out like I would on a normal sunny day, my 1st couple of laps were fine then I started to get fuel surge issues around turn 1 and 2 on my 3rd lap. My petrol gauge must have been playing silly buggers with me as it was half way between 1/2 and 1/4 when I went out but was telling me it was empty by the time I pulled in.

I quickly went off to the newman down the road and reluctantly put 25L of E10 98 octane as the only other petrol they had was regular unleaded.

By the time I got back and was about to roll up for my 2nd run the rain started to piss down and the track was drenched. I took it super easy as I watched a couple of cars in front of me spin out or slide off the track. This run however was not all in vein. With the track slippery as, and my tyres not exactly being the best ones given the conditions. I got to at least see how the new diff made the car behave in low grip situations

Unlike the open diff which would easily light up one of the rear wheels in the dry let alone the wet I definitely had more traction. Going sideways around corners is much easier to control now as throttle input has a much more direct effect on where the car is going when drifting.

The 1st run netted me times in the low 103s however the fuel surge issue forced me to exit just as the tyres were starting to come up to temp. Anyway given that I was only driving at 75% of what I normally would because the track was partially wet I’m pretty happy. Im sure on a nice sunny day times in the 102s will be easy enough. Still aiming for a low 101

[scarf]

Glad it got sorted and a very intersting post.

To put your times in perspective what would an evo/ sti run with a driver of similar ability?

[180 wanabe]

Glad it got sorted and a very intersting post.

To put your times in perspective what would an evo/ sti run with a driver of similar ability?

Dont know of any times for them personaly but this site has a heap of times on lots of cars

http://www.timeattack.com.au/about/about/sprint-track.html

slower evos from that link are in the 106s the fastest one is 53.96! that thing must bloody fly

quickest R35 GTR is 57.12

[fcruz3r]

very interesting post. are they any reliability issues with cutting off the outer set of sprockets on the drive shaft?

[Cra-Z-Boy]

very interesting post. are they any reliability issues with cutting off the outer set of sprockets on the drive shaft?

yes, it will now put more load on the smaller splines that now have a much smaller surface area .

It also runs the risk of being out of balance...just to name a few.

Edited December 2, 2010 by Cra-Z-Boy

[180 wanabe]

yes, it will now put more load on the smaller splines that now have a much smaller surface area .

It also runs the risk of being out of balance...just to name a few.

I dont see what the problem is as the other shaft is the same size as the now cut down long shaft, also has the same amount of surface area for the splines

I could have purchased a shaft that was the size I required from a wrecked 350z but I could not see the point as it was going to look exactly the same as the cut down one

The other thing to mention is that my cars throwing down 170rwkw not 300rwkw

Ill be sure to post up if something pops but I doubt it will particually when quaife themselves give instructions saying to do it

[Daleo]

yes, it will now put more load on the smaller splines that now have a much smaller surface area .

It also runs the risk of being out of balance...just to name a few.

#1; possibly, but only if you are driving through a splined shaft length that is less than the Diameter of the shaft + 12%.

This is also the rule of thumb with thread depth for bolts and width of nuts.

#2; I can't see any way cutting the end off the spline (which is concentric, and therefore balanced anyway) would effect the balance of the shaft at all.

Feel free to explain it to me if there's something I've missed.

Cheers, Dale.

Edited December 2, 2010 by Daleo