I have a 1993 Honda Prelude Si with an F22B1 I want to put headers and a new exhaust system on it. My question is can I order headers for a '93 Prelude SI or do I have to order headers for an Accord?

 

first things first, we have 4 cylinder engines; so only 1 header. not plural.

just search for one for a prelude si with an F22 in it. but honestly, all H & F series headers will bolt up, i'm unsure of the downpipe clearance though if you use an H22 or H23 header on an F@@. shouldn't be much different though.

EDIT: or not, i got confused

 

First of all, not all H and F series headers are interchangeable.
Matter of fact, H22 headers will not and would not fit onto the accord f-series motors.
If you do more research, you will know!

I would just search for accord's header.

 

This is BAD info.

All H and F series headers will NOT fit, make sure you get a header for your engine or for an H23, but an H22 exhaust flange will not line up. If you look on eBay (which I assume is where you will get your header), you will find numerous examples that fit both the SI and S model Prelude.

 

If I get a header for the H23A engine will the downpipe fit or would I have to customize it?

 

i know my stock downpipe does not fit my header at the collector.. this is on a H22 though

 

You should be fine with a Prelude SOHC header and downpipe.