Just had my Xflow rebuilt and was wondering what oil you guys recommend (the car will only be used for trackdays).

Crossflow is an old school engine design I would think a good quality full mineral 20W50
Even the Halfords classic would be fine just change at very regular intervals

Crossflow is an old school engine design I would think a good quality full mineral 20W50
Even the Halfords classic would be fine just change at very regular intervals

I have used Valvoline racing oil in mine which I used in the racing Ducati motor bikes I raced all those years ago.
Changed every 5000
miles, IE once a year, it comes out the engine nearly as clean as It went in.
Regards Denis

I use this VR1 - 1600 crossflow - VALVOLINE VR1 RACING Motor Oil SAE 20/50 5L | eBay

Valvoline VR1 in the new car.

In last years car I ran Miller CSS Classic Sport Semi Synthetic.

I would say both are very good indeed.

Thanks. I think I will go with Valvoline VR1

If you've had new rings as part of your rebuild, you definitely want a mineral oil to start with. Modern synthetics are too slippery and can stop the rings from bedding in.

I use Kendall liquid titanium 20/50 SAE for my engine, i used to use valvoline.

HI,
Valvoline VR1.
I just had a race engine rebuilt and an ex formula ford guy recommend this oil.
Euro car parts stock it , as well as Allied Motorsports etc.
Hope this helps.
Chris.

The main thing is to change it very regularly. Older engines have wider gaps so they contaminate and burn their oil more quickly. don't use synthetic. Stick with a good mineral based oil.

HI , Valvoline VR1 All the time, its about £25.00 per 5 ltrs, but worth it. If your racing, change every other meeting, or track day use, you are doing many more miles so after each one.

The xflo engine needs a highly detergent oil (ie one classified as suitable for use in diesel engines) early in its history the Kent engine was notorious for running big end bearings because the oil ways clogged up and couldn't supply enough oil to the bearings. 20w/50 oils are the also last thing you want to use. The main reason modern engines last much longer than 1960's and 1970's engines is because the modern lubricants at lower temperatures.
If you worry about gauge oil pressure when hot by all means use a modern 10w/50 or even 5w/50 this will give better protection at both the low and high ends of the temperature scale.

The oil pressure shown on the gauge is not the oil pressure within the bearing that holds the bearing surfaces apart that is generated within bearing by hydrodynamic action. The oil pumped into the bearing has two functions to supply enough oil to enable hydrodynamic lubrication to occur and to cool the bearing.

Gauge oil pressure is function of three main variables (1) bearing clearance (2) oil flow rate (3) oil viscosity.
Gauge oil pressure is a useful diagnostic symptom not an end in itself.
Increasing the gauge pressure by using a higher viscosity oil actually reduces the volume of oil that reaches the bearing and cools it therefore the bearing run hotter.

BT,

So if i get this right, my xflow runs at 60psi when cold, but 30 when hot, and you beleive this is ok? and when VERY hot, it could be down nearer 20psi

To me, this was an engine about to give up, hence todays delivery from Burtons ford, to build up a new engine!!!!