try meercat exhausts in ayr, they do the rb drag car apparently
it sounds like it will have to be a custom exhaust as the diametre you want is so large
im going to a 4inch job too (going single)
the garage it is in at the mo recons he can make a good 4inch exhaust but if i dont like the look of it i will be going to meercat
Thanks AlexH, i'm waiting for a resonse from Meercat (emailed them the other day with my requirements). Not sure if Invoauto just did the backbox for RK or the whole thing may do a bit more investigation into that one. Anymore for anymore?