PI Intake on 5.4?

Dbabb

New Member
Nov 3, 2020
1
0
1
28
Washington
I think the fuel injector issue is only a problem on the earlier, round ev1 style injector. I'd think it would run great with a pi intake manifold from a 4.6. At the rpms a 5.4 makes it's power, going to short in runner is just going to kill power where you will be driving most the time. You could always go the P71c1 route and cut up a Victor Jr as well.
I was wondering if you or someone else has any experience with the 4.6l pi intake swap to a 5.4? I recently purchased the 4.6-5.4 intake adapters and have the newer skinny injectors but I’m in a 03 F150. Only reason being is ford stopped manufacturing the 5.4l manifold due to the manufacturing covid supplies and no one has a new ford style manifold and Don’t want to wait around for the golden “99 5.4l pi intake” to pop up on eBay. Pic n pull gets robbed before the vehicles even enter the yard. Junkyards don’t know if they have a 98 or 99 nor can they tell the difference from F150 and a pinto. So I’m resulting to a 4.6 truck or mustang intake. Thinking of the GT 4.6 pi manifold because it doesn’t see to have that much shorter runners looking at the two. They seem pretty close. So any advice would be greatly appreciate it!
 

Mad Mod

New Member
Jul 5, 2020
12
0
1
Okoboji Iowa
Hello, I just saw your message. If youre interested in swapping to a 4.6 manifold, you run into a couple issues but the stock pi intake manifold from any 99-11 crown vic, which are dime a dozen, make for a fantastic option. Its a big step up from a truck manifold for power 4000rpms up but there will be a tradeoff for a loss of low speed power below 3k. The only real problems swapping is you need to adapt stock 5.4 fuel rails or swap to 4.6 rails, cruise control linkage will not work without modification, vaccum fittings on the plenum are different which is fairly simple, and youd require a new zip tube(cai). All said and done, the PI manifold will be better than stock and support more power. The adapter plates add to an already too long of runner length and is not optimal but better. Ive seen good use with plates and a victor jr. That manifold could use the xtra runner length but for an engine that cant handle 6500rpms, a short runner isnt ideal. If youre interested, I could source you either a 99 pi 5.4 manifold or a 99-11 PI 4.6 manifold.