Boost supporting mods for the street

[JDM_Import]

Originally Posted by 86TOYO2k17

I run radium dual catch cans. Although crankcase side really isn’t needed. Just DD/spirited driving. I wouldn’t track this kit without E85 and/or WMI and a oil cooler. This kit is a rolling furnace otherwise.
This kit doesn’t make the highest peak boost/HP/torque numbers. But it makes some of the best numbers off the line/below 4K so traction can be an issue. Although to be fair I have a 4.56fd swap that doesn’t help traction. Looking at a 3.909 swap when I can find a good deal on one.

Im aware this kit makes more grunt down low hence why I chose the 210. I find it more benifitial since I daily my car and mostly street driving is done under 5k rpms. Honestly Ive never considered changing final gears but Ive heard guys changing them and getting more torque. Whats the difference between 3.9 vs 4.56? Correct me if Im wrong but from my understanding changing final gearing your sacrificing top speed for wheel torque?

[86TOYO2k17]

Originally Posted by JDM_Import

Im aware this kit makes more grunt down low hence why I chose the 210. I find it more benifitial since I daily my car and mostly street driving is done under 5k rpms. Honestly Ive never considered changing final gears but Ive heard guys changing them and getting more torque. Whats the difference between 3.9 vs 4.56? Correct me if Im wrong but from my understanding changing final gearing your sacrificing top speed for wheel torque?

Yes, pretty much. The difference between gear ratio (in this case 16.5%) is the difference in top speed per gear, as well as the torque multiplication from gearing. One will do 93mph and the other 80mph in the same gear at same RPM. But the second one will have 16.5% more torque to the wheels in each gear. although you lose that advantage momentarily when you have to shift to the next gear both wasting shifting time as well as losing wheel torque from the gearing and the first one can ride out in same gear longer. You really need to choose a FD specifically for your intended use of the car and know why you want an FD swap for in order to choose which ratio is best.
But generally a shorter FD (higher number) will pull and feel more aggressively. with FI though going higher isn't really needed, and a lot of times people go longer (lower number)