I use a Dynamite aluminum horn on my T4 as well, not so much for the strength (although that's a definate plus) but for the added speed. I'm using a Futaba metal-gear servo with...I can't remember...well, more torque than I need, and this Dynamite horn has a hole that's "1 more" than the stock plastic horn. So I played the geometry game, took a little dual-rate out of my radio to compensate, and now I've got better steering response.
First tried it on my GT2 and loved it
Faster Than Factory
On The EDGE Racing, est. 2001 - Home of the 524, the Silverado Slammer E-MAX6X6, and the Sand Dollar prerunner
Mike Budzien | facebook.com/OTE.TheMissile | RIVCO Products | The RC Corral | iRacing.com