gli = d15b7 = 1493cc
b18 = 1834cc

so that is more than 15%


(1 493 / 100) x 115 = 1716.95cc.....

1716cc is the largest increase in capacity you can go without engineering.

Look at a B16a engine perhaps , or spend more to engineer correct front and rear brakes to suit this larger engine capactiy increase.