G'day from Oz- I am building a RHD C4 vette for the salt (and less ballast, for circut sprints). Have had to move the seat and steering column about 3" to the centre, to stay inside the inner plane of the roll cage. After the header collectors, the exhaust goes to the rear via 2 x 3" pipes- it will solve clearance problems, if I can use a short section of oval tube, 4" x 2" near the rear of the gearbox.
QUERY If I am careful to blend the change in cross section to minimise turbulence, can I tap into the collective pool of wisdom for advice on whether the change from 3" tube (7sq in.) to 4" x 2" oval (about 8sq in.) for about 12" in length, then back to 3" pipe, will have any substantial negative effect on exhaust gas flow?
thanks, Denis