Originally Posted by
Maximo
my modified Roma would give you nearly 10 (if not 10 ) pretty easily ! using a much bigger insert no less.............. A huge issue is setup, pipe and manifold...small inserts don't always pay off with increasing mileage and in some cases can make it worse...for a .25 a 7 mm is too small and is choking the engine and making it work harder....
Even stock Roma was too much power for me even with a 7mm. With a 9mm insert and 9886/41001, it was absolutely insane. I think it'll either hang or beat my os .28xz . Roma was also putting more stress on my drivetrain especially clutch bearing. With the Roma I learned you need to use metal shield clutch bearing otherwise the torque and speed melts the rubber shield. With the 9mm on the Roma it took out TKO clutch bearing after 4 tanks. Now I slapped in a .21 and will be running the Roma on my GT.