DOHC 5.4v High Compression NA

[Black_Mamba]

Alright so gunna go with the navi block, for sure doing the 5.4 dohc swap to my 02. Wanna bring up a new thread cause all the research I've been doing is from threads 3-5 yrs ago and havent found too many recent ones. I've read all the forums and posts and seen about birdman and his swap and am ready to do mine. Im probably going to go with the cobra c heads cause I dont want to be limited to the options for the navis heads in respect of intakes and exhaust manifolds. I realize the c heads will need to be ported to match up to my block, thats fine i would of ported the navi heads anyways. Will the c heads properly feed my 5.4? also, do all coolant passage ways match up? thatd be great if they do. I don't want to blow this engine, actually interested in seeing how high NA numbers I can get with it. I wont be doing any sleeving, only boring that will be going on is so i can freshen it in with slightly oversized pistons. I do want to increase compression tho...actually as high as I can go. Any suggestions? I know I will have to run 93 octane, thats alright. I am planning on doing manley rods and not too sure about crank yet...but ive heard to go with the diamond pistons...apparantley they sell a high compression one off the shelf. Cams I will probably go with the 98 cobra cams. Anyone know what types of numbers I will be able to make with this setup? Im open to intake options and also header options, Im not too worried about those yet. Thanks guys

 

[Ford>Chevy]

Making good power with a NA 5.4 DOHC requires efficient combination of parts. Most importantly, this comes with the H/C/I (Heads, Cam, Intake). Port Matching the heads to the intake also decreases restriction in airflow which also increases efficiency. As for compression, I would go with 11:1 if you are doing a strict na build. Definitely get a forged crank as I'm pretty sure you will need to spin that 5.4 pretty high to achieve good numbers. 5.4s don't like RPM because of the increased stroke, but with the right parts, higher rpm can be achieved (7-7.2k I think). That is why people sleeve 5.4's instead of stroke them. They are already stroked enough. I would talk to na svt. He knows all about these na builds. He could tell you what you need and he can probably spec out a cam depending on what you want to do with the build. Good Luck.

 

[Blkkbgt]

Along with talking to NA SVT I would head over to corral. There is a nice NA hp and tq list in the DOHC section as well as a ton of info. There is an Australian guy over there that has found a cheap way to stroke a 5.4, I can't wait to see his numbers.