5.4 2v Swap Basics (as of 2022)
- Thread starter garrittpwl
- Start date
Depends if you want forced induction or naturally aspirated. Forced induced, yes. Naturally aspirated, possible. This all depends on how the shortblock is built
I was thinking naturally aspirated and 2 valve heads (Trick Flow) would keep the assembly smaller, simpler, and a little less expensive. I assume better rods, longer duration cams, and at least 11-1 compression would be essential.
The heads will uncork the top end for sure. One of the down falls of the 5.4l and its aftermarket piston selection (97%) the same as a 4.6l. You want to look for a piston compression height of 1.330"ish range. The normal piston compression height for a 5.4l and all other 4.6l pistons comp height is 1.220" and the same for stock pistons as well. The piston is a tad under .100" of the deck surface. Youll want the piston to meet the engine deck surface at least zero. This helps power production.
You are correct! Which in tail follows front cover, timing chain and intake modifications. Its not impossible to do and works well. If you are ready to build a special engine. Keep in mind the same horsepower output can be achieved from a 4.6l. The torque output of the 5.4l is fantastic, but horsepower remains the same achievable potential from a 4.6l
Intake options and under the hood fitment mostly. The 3v heads have their faults but mostly due to neglected maintenance. Great hp can be had and the theory is great
From what I know, there are lock out kits for 3v.
The 5.4l swap is a fun swap, but this engine power range is low end pulling grunt. It makes for a very fun driver. Strong 5th gear driving power but the horsepower potential can still be had with a 4.6l. Their is no need for a low rear gear ratio above 3:55.
The 5.4l swap is a fun swap, but this engine power range is low end pulling grunt. It makes for a very fun driver. Strong 5th gear driving power but the horsepower potential can still be had with a 4.6l. Their is no need for a low rear gear ratio above 3:55.
Snorky
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Modular head shop has forged 5.4 zero deck forged pistons with 2 valve piston reliefs. They're about as expensive as any other forged piston. Check it out
After having done the swap to a 2v 5.4l and driving it.....its ridiculously strong at low rpm's. And this is where the engine geometry favors its output. Long story short.....in quick quartermile drag racing there has yet been a 5.4l engine to out do what the 4.6l is doing. Not to sway you away from the swap, because its hotrodding at its best. Its fun!
The added front end weight of the 5.4l can be offset some by relocating the batt to the trunk, aftermarket K-member helps weight and opening up room for headers if you go that route. Speaking of headers. Do yourself a favor and do not attempt long tube headers on a 5.4l with a stock K-member.....you will hate your life afterwards. Be sure 100% with your 5.4l build before installing.....removing valve covers or just working on the engine in general is difficult do to its big size.
The added front end weight of the 5.4l can be offset some by relocating the batt to the trunk, aftermarket K-member helps weight and opening up room for headers if you go that route. Speaking of headers. Do yourself a favor and do not attempt long tube headers on a 5.4l with a stock K-member.....you will hate your life afterwards. Be sure 100% with your 5.4l build before installing.....removing valve covers or just working on the engine in general is difficult do to its big size.
My last builds was a high compression npi 2v. I wanted to see how the 5.4l 2v would respond with zero deck pistons, so I sourced a set of 1.330 comp height pistons that made the static compression 18:1 and I ran E85. It ran ran great, but was a tad bit to snotty. After running it a bit, I realized high oil consumption. Pulling it all apart I found the 2nd piston ring was fluttering. To make things quick, I just reinstalled stock flat top pistons, significantly reducing the comp ratio and being a little more gas friendly and more importantly piston to wall clearances. The high comp piston I was using was sized for propane fuel racing, which in turn is a different shape and size. I didnt know that then, but I learned. Anyway, long story short, running the npi ported heads, comp274 cams, edelbrock intake I had to set the rev limit to 6500rpm and the power was great. My guess-ta-mation of power by racing other know cars was in the 350rwhp range.
Well, I think that is more than sufficient for a fun daily driver like I am thinking about. 350rwhp is about 400 crank hp, right? 6500 rpm seems plenty high for my purposes. I don't need a 1/4 miler. How was the lope with the 274 cam, do you think you could run a/c (Arizona)?
Absolutely! The 5.4l torque will not be affected by a/c with any cam. The lope is fantastic!
