I had them on my totally std 1600 with no supressor and it caused resets. However, this was on a totally knackered (ie from a scrap yard soaked in water) set of plug leads. I changed the leads to new ford and fitted the supressor and had no problem.

I had them on my ST engine until Richie robbed them lol, but that uses a peak and hold driver board so won't generate any noise.

On Richie's car, there is no supressor and it works very well. All ECU grounds inc sensors ground to the inner wing where the battery grounds. You should ideally be running your CPS wire away from any others, and especially away from injectors and plugs/leads.

What CPS wire are you using? I use microphone cable, it is very flexible, and double shielded. On Gary's Fiesta I had some slight noise issues, possibly to do with his 780cc low z injectors. The Gotech CPS wire didn't look to clever so i ran another using microphone cable and it's absolutely perfect as 12.8 @ 123 proves!

Rick