thanks for the reply
its just a few people are trying it in the uk that i know of.i was gonna give it a go as i have a spare set,and a bit of time on my hands.
i know the head port sizes ,thats why i said i would taper the lim down to that size .
but if theres not much to be gained or possible loses ,theres no point.

2001 mondeo st24 rsap saloon,piper x cone filter,pro flow 75mm maf,cta,svt tb,silicone engine hoses,ecotec valve,twin cat back zorst,17 inch bsa 214 alloys,lowered 40 mm,st200 full interior