What is the max hp that the stock fuel filter can support?
Anyone know? Would i have any issues around 400hp?

 

Anything under 400whp you should be good. That being said, 400whp is the range at witch some people would suggest that you should start upgrading the entire fuel system. Including higher flowing fuel pump, larger hose/tubing diameter and reducing any flow obstructions....ie 90° angles or bends, banjo fittings and/or reducers. The straighter the flow the better the return on holding the required fuel pressure.

 

I have the walbro pump that I haven't had the time to install. AEM RAil with aem fpr, RC 550cc. stock filter and fuel lines.

Any advise on changing the pump?

I was just thinking about changing the filter because the engine is out of the car again.

 

Only advice I can think of on changing the pump is too be careful when you drop the tank. Don't let those tank straps hit you in the face on the way down. Also check all of your lines while your under there. If any of them look like they are starting to rust/rot. Now would be the time to change them.

If you have the motor out now would be the time to swap to an AN sized filter and bigger AN or stainless steel fuel lines.