a few diff questions, i know there is tech stuff but i want a bit more specific info please

so they are weak??
how weak with 100hp at the wheels?

what breaks?

are the 1000 diffs shorter the 1200 and by how much?

maybe even a weight comparison between the 145 and 165?

ben

My personal opinion is yes they are weak but also no. My first one took over a year before it broke to be replaced by one which lasted less than two weeks of even less spirited driving. It depends on the condition of it. How many k's how much flogging its had over the years.

Its the sharp jolts that kill them. Clutch dumps, hard shifts.(thats what broke mine, gun it in first in a straight line and hit second hard for some sideways movement). Id say hard street duties would be worse than racing as it is more sharp driveline impacts than a smooth flowing circuit car.

Weight. The ute diff is quite abit heavier. Dont know the actuall difference but id say about 15kg heavier. Lowered the rear of the car slightly more due to the larger axle tubes and did cause my car to axle tramp if traction is low in a straight line(both wheels spinning) only slow spinning though. If it really breaks traction no worries.

H145 for me it was spider gears that kept breaking although im sure if you welded it and it was your daily driver axles would then break.

Yes 1000 diffs are shorter. How much i dont know. By changing the mounting points on the housing a h165 will fit a 1000 with flares or by running front wheel drive offset rims.

With a 100hp at the wheels in a street car say goodbye to the ol h145.

i am really keen to keep the weight down so i would rather weld up a 145 with alloy nose then go to the 165 espesially as i have done a 4 link conversion so its not a case of just bolt it in!!

if the centre is weak then i can try to convert the centres or is this not possible? or can i get the side and planetary gears (165) in the 145 carrier?

are the axles on a different spline? if not will the 145 side gears accept the 165 axles? and where so they break if they do? at the spline i would imagine?


thanks for your quick reply

ben

Early mid 60,s datsun bluebirds have aluminium 165 housings (10kg lighter than cast iron ) and use same axles as a 1200 ute
I have used this set up in my race 1000 for about 8 years doing many sprints and hill climbs (big burn outs to heat the tyre,s ) and only broken one axle
my rear gaurds are flared to fit the wider diff housing

H165 is much bigger so it doesnt have a chance of fitting the h145 housing. Dont know for sure about the splines. H165 axles are a fair bit thicker too and have much larger bearings. Work out your driving style and what you need it for then decide. H165 is definately the better if your a bit of a thrasher and the h145 is better if you want to keep weight down but are prepared not to flog the living hell out of it.

My H145 with alloy centre is barely able to handle me 98hp
I have once centre with a broken axle
2 centres have stretched the alloy housing.... so I had to fit the 4.11 centre out of my white coupe recently to keep the racecar going
I'll be looking for something stronger very very soon

I have a worked A15 with an H145 and drive it enthusiastically, its still going after 5 years, the gearbox is more of a worry than the diff.

If I wanted to really launch the car and go for it 100% I could destroy the diff and the box in an afternoon, its all down to what you want to do with the car.

If you want to go drag racing the H145 isnt for you.

You could put an H150 centre in from a 120Y, I knew a guy who broke 2 H145s then went H150 and it survived more than 2 years of harsh punishment before he sold the car.

I have a little 1200 coupe rally car and we give it a very hard time all the time on dirt and tarmac with lots of burn outs and clutch dumps and she has been fine. The A14 with twin dellortos puts out 79hp at the wheels so its not awsome power but enough to have some serious fun with. and a new assy (when we need it) will be either free or $20...

all good answers
i used to give the car absolute hell and i never had a problem but it never had any power

i was guessign about 100hp at the wheels but that was from twin sus so if u only make 79 hp on dellortos then i guess this may have been optimistic

i have made a 4 link for the 145 and i have a few alloy housings and the car HAS to stay under 700kg so i guess then i am on the right track

check preload and wipe and a new set of bearings and i should be fine if i drive it well (smooth)
the car should be light so it should take a bit of stress off

i have a 60a 5 speed, r they a bit weak too? i didnt think that they were too bad


thanks again


ben

http://groups.yahoo.com/group/datsunb10/

The change from first to second can take its toll on the 60a,but again it depends on your driving style.