Просто добавьте множитель к значениям кадра в функции setImage на AFItemView.m
- (void)setImage:(UIImage *)newImage originalImageHeight:(CGFloat)imageHeight reflectionFraction:(CGFloat)reflectionFraction {
float multiplier = 1.5;
[imageView setImage:newImage];
verticalPosition = imageHeight * reflectionFraction / 2;
originalImageHeight = imageHeight;
self.frame = CGRectMake(0, 0, newImage.size.width*multiplier, newImage.size.height*multiplier);
}