Just an observation...

[UberSilver]

So me and my Yaris come in at 2500lb. So all I need is 250hp to get a nice 1:10 ratio If I had no concern about mpg, a rotary out of a RX8 would do it.

But I do like the near 40 mpg I get, so I'll leave it alone. Plus my bike is 1:3.5 with me on it. And thats my extreme fun ride.

Originally Posted by Captain Slow

Yeah, I really don't have a problem with the $ per hp cost of modifying this little car. Sure there are less cheap eBay versions of stuff around but still lots of good quality parts.

Take into account the fact that the 1990 Mazda Miata made 115hp and weighed around 2100lbs...that puts the Yaris (especially modified) solidly into Miata quickness territory. I owned 2 Miatas and neither were 'fast" but they certainly surprised a lot of people too.

Power to weight ratios mean a hell of a lot in the real world. Below 1:21 means 1 horsepower for every 21 pounds of weight.

Yaris (unmodified) 1:21
Yaris (I/H/E) 1:17.9
Miata (1.6L) 1:18.3
Honda Fit (2013) 1:21.3
Mazda 2 (2012) 1:23.1
Nissan Versa 1:21.6
1996 Civic hb 1:21.2
1998 Mustang v6 1:20.4
1992 240sx 1:17.7

Take a long look at that list, the Yaris has one of the best power to weight ratios of any recent hatchback (other than special models like Civic Si, etc...) even when in stock form. Very impressive.

Imagine with some lightweight wheels and pulleys, remove the rear seats and spare tire, intake, exhaust, header, MI manifold, 1ZZ tb and a free flowing midpipe...I think the Yaris could easily hit 1:15 or 1:16.