do they affect your car overall? i do lot's of highway driving, so will this affect mileage or anything?

 

I honestly don't see how... Unless your cap is broken or defective. What do you think?

 

well they have a higher pressure rating so i thought maybe somehow it could affect something somewhere

 

The advantage of a higher psi radiator cap, is it raises the boiling point of the coolant. I believe it is somewhere around 3* for every 1psi increase. The stock radiator cap is all you need on the prelude, since they only run about 170-180* stock. The only engines that need a high psi cap, are engines running above 220-230. (methanol sprint car engines, etc)

 

thanks. so it's pretty much a barely noticeable engine dress up mod?

 

haha yep