The Triumph Dolomite Club - Discussion Forum

You want a real good 20/50, or even 20/60 if you can find it. Millers or Valvoline seem to be popular with serious users.

Smart money says the spin on filter actually flows worse (maybe up to 40% worse) than the original cartridge filter!

Steve

Depends on driving style.
People who potter about to car shows and breakfast meets etc, any old "classic" 20/50 will suffice.
Start driving the car harder and there are better options.
Valvoline VR1 was OK, but I have fould Millers CSS20-60 to be excellent at maintaining viscosity and oil pressure (though that is not the be-all) Also heard very good things about Penrite oils from a chap wo regularly uses 7000rpm in his TR6 (yes, he has a steel crank!)

The only actual benefits of a spin on filter on a Sprint or 1850 are a slightly cleaner filter change and you don't have to worry about avoiding the cheap filters with cardboard ring spacers (as opposed to a raised metal lip) which can come adrift with expensive consequences.

The 1500 and 1300 however benefits as their filters don't hang downwards as the Sprint and 1850 do, so can drain down giving a 'dry' start; the spin on conversion on these can either turn the filter through 90º so that it does hang down and doesn't drain, or if the adaptor kept the filter in the same orientation, spin on ones with an anti-drain valve can be used.

Personally, I'd keep the £50 or so the adaptor costs and keep it standard. The quality of the adaptors is variable too, with a large number that leak, though when this is reported to some retailers they claim its not a problem they've experienced before...

It's the difference in construction of the adapters. A spin on conversion isn't a bad idea at first but at the slant four it's a forced construction just to be able to use a modern type filter. It's restrictive and not an improvement. On the big six engines the spin on is really an improvement but that adapter doesn't restrict and is constructed differently.

Jeroen

new to this wrote:
P.s. any other mods improvements i can make while i have my Sprint engine apart ?

You have a day of two?

Jeroen

I run the re-launched Duckhams Q 20W-50 in both my Sprint engines and they seem happy on it, but like folks says just choose a good quality one.

new to this wrote: ↑Sun Mar 27, 2022 10:00 pm

P.s. any other mods improvements i can make while i have my Sprint engine apart ?

Measure the bores and bearing journals for wear and bore/grind if necessary. Check the oil pump for wear and blueprint it, If you have to buy a new one, blueprint that one (quality of available replacements is highly suspect, you can't just "fit and forget") get the flywheel lightened and all the moving parts, crank, rods, pistons, flywheel, clutch cover and pulley balanced. Get the valves seats 3 angle cut. Check the head is the same depth at both ends, if it's OK give it a light skim. Check the jackshaft bearings carefully, (and before you spend ANY money) a problem here is as good as a death sentence to the block!

All the above is just to produce a GOOD standard engine. If you want to go faster, then the sky is the limit.

Steve