MyFX4Project

Starting to build a 5.4 for my 2002 FX4. I've got a 2003 expy windsor 5.4 block and PI heads that have had a 5 angle valve job with new valves, springs, rocker arms, stock cams (for now). I have all the parts for the short block.

I know the first thing I need to do is get the block cleaned and have the cylinder walls bored. I just need some help with how much to bore it, what pistons are ok to use and where to get the bearings and what kind. Il be using the stock crank so ill take that to the machine shop with me to have it checked out. Ill be putting cams in it too and I'm thinking some stage 2 cams but not sure what to look for.

This is my first ever engine build from scratch. I am very familiar with how they work and go together etc so assembling it isn't any concern, its finding the right parts to achieve the best results. If I can find a supercharger off a lightning ill highly consider throwing it on too so I want the engine to be built to hold if the opportunity arises.

I'll be happy if I'm in the 300-350 hp range. I don't need any more than that.

Let me hear your thoughts!!!

F-ReV

Can't wait to see this build 300-350hp is reasonable without a supercharger, and shouldn't be a problem. I personally think you should keep it N/A

jferg92

I wouldn't leave the stock bottom end. Get a factory lightning crank (forged). Check out modmaxracing for a rotating mass pkg. it has your choice if forged crank, rods, pistons etc

MyFX4Project

I'm nit leaving the stock bottom end, possibly just the crank lol thanks for that website though! That'll help me a lot. I'm thinking flat top pistons. I need to save a little bit if I'm gonna spend 1400 on just the bottom end. Still need cams and block work haha

jferg92

Gonna bore 20 over?

Jacob.P93

X2 man 20 over make her a 350 LOL. save up some more and do it right so you have no worries and a super reliable motor and you don't have to take her back apart after you get her in. And going forged would give you better reliability if your running her high rpm and would afford you the option of going boosted IF you wanted to man.

MyFX4Project

Very true. Like I daid I'm not going for a 450hp motor or anything crazy, just want it to be fresh with a little more umph than a stock 5.4. I might swing by the machine shop tomorrow and talk to my guy about what he thinks.

Jacob.P93

Double post sorry.

Jacob.P93

Yeah he would be a good source of info and he can inspect whatever you want to put back in and give you a for sure rather than me just rambling. I think it's gonna be awesome! I think 350 is easily doable ad with lt heads cams and bored over you could be pushing 400. And still be reliable as all get out.

MyFX4Project

Stop talking numbers... you're getting me excited lol gotta save up some more money too before I do anything. I'd rather not blow all of it on an engine I don't need haha