3S-GTE in a KE70 - I would say is an overkill, 3S-GTE 4th Gen is stock 280hp - Will your KE70 withstand that?
More power asks for further upgrades too - Strengthening the chassis, better braking, better handling, so on so forth. If you're trying to juice out more power out of a motor, you're not only putting yourself in danger but other people on the road as well.
So think wisely, you're only 20 - I've driven and kept KE70 as well, I think 128bhp is more than enough for it or a Blacktop would do the job.
If you're looking at turbo'd motor, go for 4E-FTE it can easily give you over 200bhp with a turbo upgrade.
Just my thoughts - Good luck with the sale.
