A slant pun is similar to a slant rhyme in that it is an imperfect pun. Basically it's when you make a kind of pun, but it's bad but you still want to count it as a pun
*looking at a picture of castle ruins that feature your friends*
"You kinda ruin the right side though, might wanna get that cropped out"
The word "ruin" would be the slant pun.
A well known Six Cylinder engine found in Chrysler products such as Dodge Dart and Plymouth Valiant. They come in 170, 198 and 225 cubic inches. The Slant in the name comes from the 30-degree from vertical angle the cylinders are inclined at. They are very reliable.
Dad's 1976 valiant is a huge POS. The trunk, floors, fenders and rear quarter panels are rusted though despite being a southern car. It corners horrible due to torsion bar suspension. That said it's 225 Slant-6 in it ten thousand times better than the car Chrysler built for it.