edit

 

So you need a pi truck intake, elbow and throttle body, which should not be too hard to find, maybe some other minor tweaks as well.

The Lightning came with dished pistons so your compression will be lower.

 

the throttle body and elbows are different?

 

I duuno. Here's Neal's build thread, 99' pi truck with lots of good pics.
https://www.f150online.com/forums/v8...d-up-pics.html

 

Wow! that was a really inspiring (and really long thread)!!! thank you for posting i will definitely bee getting some ideas from it as i move forward.

 

Yea, Neil just sold those heads recently. Kick myself, I should of jumped on those lol.

As far as porting the aluminum. I've done my 98 myself. Just a light port and knife. Didn't remove the divider, -knifed it. Took out enough that I had to port match the lower to the upper afterwards. Didn't dyno or notice any differences. The ONLY thing that I've noticed over the years is that the throttle body (polished) and upper does not get dirty. However, I'd like to believe it did it more good than that, but that's as far as I went with it at this point.

Porting was accomplished with a worm drive. I believe user ONELOWF pointed in the right direction acquiring that tool in the past. It's kick *** and very strong!

Turbulence. -In case your unaware, -it's not so much the casting flaws anyway in this case, -since the part passageways are more than sufficient in diameter. P&P just adds to everything else here. It's the damn transitions(if plates are corped) and that lower intake as you mentioned. Smooth transitions (plates), -no bottle necking or tripping. As for that lower, - I'd like to see a correct OR actual simulation of how that all comes together lol. I can imagine, but can't.. Uknow? Soo, -there's always been some question on this end.

Interesting thread

 

Also, as far as headers, -

You want Long Tubes period. No other. They fair VERY well with the modular 5four. Dyno proven w/same 5four engine days apart. Comparison trial was from factory to shorties, then shorties to LT's. NO gains first trial. 2nd showed 30 hp 35 torque gains.

One important aspect to LT's is to make sure that have a 3" collector. Some OBX sets do not. Pacesetter sets are the longest w/large 3" slip fit collectors. OBX can now be purchased w/3" collectors. Still, the OBX is new in this style so I don't have much info about them. The OBX hasn't had fitment issues like the Pacesetters have had in the past when installed on some 4.6L 4x4 models. As far as I know, no issues with either makes when installed on the 5fours. The angle and taller deck height of the 5four makes for proper fitment. That's the way it's been in the past.

Personally, I like the Pacesetters. I've been running them since 05 without an issue. I welded my High Flow converters directly to. I had customized these converters a little. I cut out and removed the 2.5 flange on one side. Welded in a 3.0 flange in its place. So the cat slid over the collector to be welded. This gave me plenty of room for the rest of the Y. It's very tight down there with the 4x4 models. - It can be handled fairly easily and IMO, it's a good transition point if you choose to run a 2.5 Y. The cats hold up.

 

I'll fight... I mean bite lol. 3" is way over kill for these motors. Unless you are pushing 600+ rwhp wouldn't worry about getting 3" collectors. 1 5/8" primaries with 2.5" collectors is a good match for anything that will be street driven. The only time I would think of getting 1.75" primaries and 3" collectors would be an all out race built vehicle with minimum 600+ hp.

As well obx headers will not work on 4.6L trucks. Look up user Jackal (think that it is how it was spelt anyway) He did alot of work to make them work.

I actually started to research headers IN DEPTH once upon a time. I got to the point where they were talking about the length of Primaries depending on tq curve, then at the rpm, then collector size, angles of the bends of each primary. Then to the size of the primaries, then to the collectors. It got to the point where I said screw and just bought the obx's they'll be good enough. Anyway my point is that you will never have any benefit from the 1.75/3 over the 1.625/2.5" headers

 

so porting is a waste of time but polishing will help keep things clean and will help with performance in the long term? im still trying wrap my head around how it works. i need to pull the manifolds apart and get my fingers in there i wish there was a simulation of the manifolds in action. it seems to be an ingenious system. i just wish there was more i could to to improve it. it is an extremely tall manifold at that... anyways lol

i agree with you on the headers. i have always like the longtubes (i wrapped them and put em on a 91 'burb with 3" true duals. that things sounded like a sports car and accelerated as smooth as silk ) i will eventually do the long tubes and do 2.5 trues all the way down (i already have the cat delete). i bought it originally with one of the really good flowmaster (2 outlet) and it sounds really nice. ill probably wait until it goes out or maybe after i pay for the next semester (and the engine).

on that manifold, i keep thinking of ways to improve it (custom, modded lower, p&p etc.) but it seems like it isnt worth it. i think i will have to look further up the intake and on the exhaust to get what i want.

 

No fighting, if you know what your saying lol.The 4 primary's converge to one, then converge to 2.5 thru the converter. IF don't think that's a BETTER transition, then I don't know what to tell yuh. That's transition to the the Y, -nothing more.

Your talking about an off road set up. Where they run a 3" Y. That's ONLY done because those trucks are set up to run WFO. In other scenario's, -the 1/4 mile, drags or whatnot are set up to promote the higher end. Those builds usually have all they need down low to begin with, well enough so that improving the top end nets better times. Unless your going for a wheely record of some sort. I've seen that as well lol.

Nope, I'm speaking of a usable hp/tq set up. On that is suited for stock/modest builds. More-less for the DD and when she has to gidit..Smooth transition into a 2.5 and out. HF converters do this well. Which is most likley why OBX finally got on the band wagon... They probably did some actual testing or saw it for themselves,- somewhere.

 

I quit lol.

 

I'll put it this way, it may be easier. You can rip the exhaust off ANY gas engine and you won't lose hp or torque ANYWHERE in the power-band.

The ONLY time that's a loser is thru programming. It's been that way for decades and still is. It's just today everything is managed thru software, chips or whatnots (AF's). Tuners have a much different job today, then say 20 years ago.

BTW-Modular Mustang just proved that AGAIN, not to long ago. I don't know why, but they felt the need.

 

maybe i dont understand what you mean by "knifed". are you saying you took out the walls going across the lower manifold but left the one through the center? and you didnt seem any performance/fuel eco from doing it? I might be better off upgrading to a bigger throttle body and elbow with a CIA?


or is this what you mean by knifing:

http://www.v6f150.com/showthread.php...-Throttle-body

(filing the edge of the throttle plate)