Car: 9th Gen 1.4 Petrol SE + Navi
Join Date: 13th March 2017
Location: Essex, UK
Thanked 299 Times in 269 Posts
I can't see any real way to extract much extra power for £1000; Induction and exhaust could happen, but you're still NA - They'd improve responsiveness and perhaps net you an extra few HP, but nothing massive; Even if you bung on an Ebay Turbo for £1000, you've got no budget room to improve brakes / chassis.
A curveball suggestion would be using the money to take some instruction; Carlimits, High performance course etc. - You'll see a big improvement in abilities, and that applies to every car you drive.