I had this page bookmarked from awhile back and although not a tremendous HP increase it is a good bit over stock for the price ....

I would kinda like to know if they heads work stock units or if they had been worked .

The std bore JE pistons are just 220.00 a set from my source and the Honda ring sets are but 32.00 each . Moriwaki Stage I cams that use the stock springs are 599.00 from Big Valley Honda so if you already have the exhaust and jet kit thats not a bad price for a winter redue with some good performance gain . The JE pistons are 11.6.1 compression.

Compression = torque 8)

http://www.hpower.com.au/

 

Here is a German website where the builder has taken and built a 1120cc VTR . Click on " tuning " and scroll down to see the chart

http://www.thiel-motoren.de/Start.htm

My general translation of the page goes like this :

Stage I
Portwork and valve job with jet kit and airbox mods = + 10hp

Stage II
Like stage I but with cams + 5PS and 2 lbs torque

Stage III
Akroprovic exhaust = another 7ps

Stage IV
All of the above plus the sleeved piston kit to 1120cc and it made 130ps and 125 newton meters of torque