The Jensen Owners' Club

kees wrote: ↑Mon Jan 04, 2021 7:38 amHotchkiss Anjou.

Close but no cigar!

Photos of the Image wheel that was based on the wheel from eBay:

https://www.joc.org.uk/forum/viewtopic. ... 6&start=80" onclick="window.open(this.href);return false;

https://www.joc.org.uk/forum/viewtopic.php?f=11&t=30678" onclick="window.open(this.href);return false;

Probably the most common gasket compressed thickness would be 0.040". So it is straight forward to go with zero deck height (pistons flush with deck) and 0.040" head gaskets, which gives a good quench height of 0.040". You could use the same approach with any gasket between 0.039 to 0...

I'd say 0.040" to 0.045" is a good range for quench height.

If you are going to skim the block to square it up, then you might as well ensure that the quench height is optimised. - It will increase the compression ratio which will help with energy efficiency and power as well as giving you more options when it comes to camshaft selection - It will improve qu...

You used to be able too buy some templates for the ideal port shape. Some one I know bought a set of heads that had already been ported and he reckoned the engine was a lot more free revving. If you are after a little more efficiency from your engine getting the compression close to 10 to 1 is a go...

An extreme example of how port mismatches may not make much of a difference relates to the Big Block Chevrolet (BBC). A square port inlet manifold has been proven to work very well on an oval port head. See the image to get an idea of the degree of port mismatch. http://www.usmuscle.com.au/Forum/att...

Pocket porting is well and truly worth the effort, but port matching commonly yields little to no improvement.

Why would you need to run 98 RON unless you have a modified engine? I have run my Mk. 3 on NZ 91 RON for 16 years with no issues and I have a slightly increased comp. ratio (9.2:1 if I remember right!). I was actually thinking of the B motors that had a 10:1 compression ratio vs 8.2:1 for the RB mo...

That makes more sense.

Wouldn't most of you use 98 RON anyway? It won't be good if even the 98 RON has 5% ethanol in it.

Surely nobody runs a Jensen on 91 RON fuel?

A cool video showing the difference viscosity makes:
https://www.tec-science.com/wp-content/ ... cosity.mp4