Roadster Axles

[peterj7]

I have a Fiat engined Roadster with a Marina 1.8 rear axle (3.63 :1; (14" wheels)).
I have started to get the dreaded axle whine on the over-run. Does anyone know what my options are for a new Diff. or alternative axles?
Do MGB axles fit? are new parts avilable to rebuild the diff?

Peter

[amalgamated users from prior forum]

Re: Roadster Axles

Message originally posted by: tom ainsworth
my fiat engined marlin has the complete fiat drive train
131 engine, gb shaft and axle/diff
maybe find a fiat 131 or perhaps one of the older estates?
maybe lancia delta integrale back end?

[lil_red_roadster]

Re: Roadster Axles

The complete axle from the 4-speed TR7 axle is a good swap - it comes in 2 flavours, 3.63 or 3.27, the latter being from the automatic. Alternatively the 5-speed TR7 axle (Salisbury type) also has same track and wheel PCD. This comes in 3.9 or 3.08 flavours. The Dolomite Sprint axle is also a good candidate. The MGB axle (early banjo or later tube-type) might be a little narrower on the track but is strong enough - watch out though as the wheel PCD is 4.5" rather than 3.75" - you could get around "mismatched wheel syndrome" by fitting the Marina van (575) front hubs. I believe the Marina van axle and early MGB banjo axle are closely related.

[peterj7]

Re: Roadster Axles

Thanks guys, I'll look into the TR7 options. I am reluctant to go the fiat drive train route since I took the remains of the Argenta donor including the axle to the scappie and spent several days on my Myford making the fiat gearbox to Marina propshaft addaptor!

[amalgamated users from prior forum]

Re: Roadster Axles

Message originally posted by: Ben Caswell.
If you dont want to change the axle you can drop the half shafts out and just change the diff. you have a choice of diffs from
MARINA 1.3 =4.1
1.8 =3.636
Triumph Dolly 1850 =3.27 in the auto
=3.63 manual
and RWD Toledo 1500 =3.89
" " 1300 =4.1
Hope this helps

[petermads]

Re: Roadster Axles

Long time since a posting on this subject. I have a just- deceased Marina rear axle with bolt-on wire adaptors. Yes I know expensive but an indulgence and look great. Can anyone tell me definitely that an MGB axle will fit a Marina roadster? There will be permutations with disc or wire wheels, but apart from that, any problems?

[ggrum]

Re: Roadster Axles

Out of interest my 3.63:1 Marina rear axle driven by a 130hp Alfa engine whines slightly under power but is quiet on the over-run which I imagine is the more usual situation. Its been doing it for years now but never seems to get any worse unless of course my hearing is deteriorating (quite likely due to too many pub rock bands in the past!). I was once told by a member of the Marina owners club that it can be quite difficult to find a Marina axle that doesn't whine a bit. I think we are more aware of it in the Roadster because we are virtually sitting on top of it.

[lil_red_roadster]

Re: Roadster Axles

Triumph never used to worry about whining diffs...the cars were so often stationery due to seized engines...

Anyway...having gratuitously insulted all Triumph afficianados I'll move on...

It's interesting that we give the Marina axle such a hard time...I found some interesting comments from a Caterham fan who reckons a Marina/Ital axle ought to be good for up to 190bhp...there are also some useful tips on building a more robust axle.

Here's the link

http://www.pistonheads.com/gassing/topic.asp?h=0&t=792159&mid=0&nmt=Which%20axle%20in fo