Have a raceline water rail on the car, been running with an expansion tank in the system. But it has developed "issues" so last night removed it from the system, and the overflow from the water rail cap now goes to a vented overflow bottle.
The cap I changed to a 13psi one I had (the original was a motorcraft 100??seemed very hard )
Does this sound about right? I presune any water expelled when hot gets sucked back when it cools?
Cheers
Clive

Can of worms springs to mind... 'developed issue', interesting, what issues were you having in the first place?

I had issues with mine and worked round them although I blame the water rail and not the expansion bottle.
ATM my rail and bottle co-exist happily but the engine doesn't get up to temperature

Steve

The issue was a crack, small but there
TBH would prefer a header just so it is easy to see the water level, but about to do a 2000mile "round britain" drive this weekend (yep, 2000miles, 48hrs) so a bit shortof time to get a replacement together.