depends on the size of the turbo/s that you will be running. a driveable (not HP monster/drag) car running twins will come onto boost a lot quicker than a bigger single due to having to spin up less mass. but then of course you can also get into custom sized exhaust housings to accelerate the exhaust gasses so the bigger turbo spools better, but then becomes a restriction in high rev ranges (though probably not a big restriction). a good comparison is between the 1jz and 7m. motor differences aside, the ct12a's spool a lot better than the ct26 on the 7m, getting the car onto boost sooner, which gives the 1jz a deceptive feel to the power delivery due to it being smooth. where as the ct26 takes a bit longer to spool, and when it does, it snaps onto boost, giving more of a feel of acceleration due to more force of suddenly coming on.
a lot of the time the reason people convert to single turbo is simplicity of plumbing. with a single turbo setup, you have more room to put things just where you want them, whereas with a twin setup, things get cramped up real quick.
hope that helps.
|