Do they exist for my '91 Prelude SR with a B21A1 ??
It seems like I can only find short ram or CAI intakes for
'92+ 'Ludes (4th & 5th gen.). Am I looking hard enough ??

 

If all else fails, make your own intake

 

you can get a weapon r intake for the 3rd gen, or you can use one from an accord or civic. you just have to either relocate you battery, or you can just cut down the piping and put the filter wherever you want. if you get one for another make, just plug the second larger hole in the intake with a rubber plug or something and you are set to go.

 

Are there any performance gains to be had simply by removing the resonator box from the intake just behind the radiator??

Also , there seems to be a strange vent which points at the battery which sprouts out from the air inlet tube, just behind the hood... I'm assuming this serves to to reduce noise levels ??

 

remove all the plastic tubes and crap that goes to the oem intake. you may not notice any performance increase, but you will be able to get a lot more air into the intake, which will give better gas mileage and a little bit more hp. probably 2-3 hp, so nothing really noticable.