carburettor spacer

[Biggles1957]

I'm going to fit an Hif38 and see that you can get both alloy and 'plastic' spacer blocks - I wondered which was best to use? I know the older type plastic ones can crack and leak with age but if the idea is to insulate from heat then surely the alloy ones aren't very effective at that? Also there are different thicknesses....

[liammonty]

I've been using a plastic one (from Minispares) for the past 14 years without any trouble.