Rover Sports Register Forum

Hi all, as above really, what's my mph per 1000 rpm in top in my 1935 14? Anything above 40/45 seems rather urgent.

I worked out that my 1947 16hp done around 17mph per 1000rpm
Not sure how relevant that is to your 1935 14hp

Hi,
I've had a few of this model, unfortunately the very low 5.2 rear diff. and 17" wheels at 1000 rpm
gives you little more than a brisk walking pace.
I my opinion the same year 12 hp model is a livelier drive.
fitting a higher ratio diff. makes the car 100% better, I used a 4.3 P4 one.
cheers Jeff. Lee

Will later diff fit straight into 1935/14 P1 housing and half shafts?

Hi, the diffs after the war up to p5s and early 4x4 with 10 splines are interchangeable.
The only Straight Swop option for your 1935 6 spline 5.2 diff. would be a 4.88 6 spline out of a 12hp (there's one on eBay)
On my 1936 14hp (rod brakes) I changed the axle for a 1946 10hp then fitted a P4 diff. and had prop-shaft extended 1-3/8". this distance varies on model.
On post war P2s the track was widened 2" to 54" on all models except the 10hp
Its this 10hp 52" narrow axle you need as its the same width as the 30s models, then you will have a great choice of diff. ratios.
By the way I've done a few diff. changes and the 1936 Sports Saloon is the worse due to the 2 seat squabs and metal frame over diff. instead of
the usual large removable steel pan.
I consider this upgrade to be well worth doing and have always been delighted with the difference it makes to the drive.
I've just bought a 3.9 P4 diff. which will fit straight into my 1946 16 Sports.
cheers Jeff. Lee.

Jefflee, many thanks for the comprehensive reply, it's encouraging to see that there are different options.
Just a thought, I have a spare diff in a pile of spares and wonder if it could be rebuilt with higher gear,s maybe P4, still using the 6 spline half shaft parts?

Hi, the diff. casing is very different to the post war models, there a few company's rebuilding landy diffs.
Perhaps with a little engineering work one of these could fit an up rated crown wheel & pinion to your diff.
It would be interesting if someone could do this, but I intend upgrading my 37 20hp and have already acquired
a 1947 10hp axle to swap and once changed I can then swop/change diff ratios at will.
cheers Jeff.

My spare has this number on it, what one is it "ROVER 06739

Hi, If you count the number of teeth on the crown wheel / 47 teeth = 14hp 5.22-1 OR 44 teeth = 12hp. and speed14 4.88 TO 1.
cheers Jeff.

It's 44/9=4.88, but it has 10 splines where the half shafts fit.