what is teh diameter of the stock 2000 tiburon exhaust? anybody know?

 

The stock exhaust piping on all tiburons is 1.75*
or 1 3/4.

 

then say if one is staying N/A, with 4-1 headers, GT cam, SR CAI, Barney BBTB, eventually a port n polished head and bored IM, what is the size and accessories (high flow cat/no cat, how many mufflers, resonators)for the best combination of power, without the loss of torque due to too much backpressure loss? i hear 2.5 for NA cars. correct?

 

actually back pressure gives you more torque on the low end and less hp on the high end.

And a bigger exhaust will give you more hp on the high end and less torque on the lowend so its a trade off.

the whole idea of a 4cyc needing some back pressure is still a controvery. I think it spawns from the honda vacuum motors. They are 1.6L with now low end torque so backpressure for them is good.

The Hyundai engine make some decent low end torque, so losing a bet witha free flowing exhaust wont kill ya.