Thanks. My engine is a well modified 1.6K Series with QEDs throttle bodies and carbon trumpets. I’m not sure of size, but will check. I’m happy to go with a sausage box filter, I just thought they were a lot more expensive, did just the same job as some basic sponge only and can be a faf fitting the frame! I also didn’t want to start cutting holes in the bonnet to accommodate, as my trumpets are rather biggish. Do you have any recommendations then? Ta.