Make payments with PayPal - it's fast, free and secure! registry | CVN on Facebook | tech | news | email login Make payments with PayPal - it's fast, free and secure!

Welcome to CVN - Your Panther platform headquarters!

Custom Search

Topic Options
#4075926 - 08/29/20 09:04 AM Rebuild questions
BigAl281 Offline

Registered: 05/19/20
Posts: 15
I'll try to keep this as short as possible since I know many of these questions have probably been asked dozens of times. I appreciate anybody willing to provide answers.

I have a 2000 Grand Marquis with 112k. Just bought er in January, and I reckon she could use some extra power. Also there's oil in the coolant, the intake and valve covers are leaking, and the alternator is dying a slow painful death.

I am likely going to get the following:
-Largest camshafts I can fit without PTV interference & cam followers
-Gasket and seal kit
-Timing chain, tensioners, guides, adjustable sprockets with maybe Nick at MHS doing the cam timing?
-Water pump and belt while I'm at it
-Intake(PI or possibly aftermarket if anyone knows of any good ones for less than $500)
-Ported heads(to PI or not to PI, that is the question)
-Lash adjusters, upgraded valve springs
-Alternator(Unimportant to performance)
-Spark Plugs(Does this have the dreaded spark plug breaking issue or is that just the 3v?)
-Bigger junkyard throttle body and MAF (70mm and 80mm?)
-11.25?inch torque converter

Yes I'm getting gears here in the spring. I currently have the elcheapo walker H-pipe and a couple of glasspacks and a bunch of holes drilled into the bottom half of the airbox. I plan to upgrade both in the future. Eventually. When I "need" to. I am never getting underdrive pulleys.

My questions are:
Am I wasting money getting PI heads if I plan to have them ported? I believe I read that NPI heads are only like $500 to have them done up all spicy compared to $800-1000 for PI heads. The odds are 95% that this will be done on junkyard heads either way because I don't have the convenience to have my car unusable for many weeks while the heads are getting worked on. I've also heard that the ported NPI heads flow better than ported PI heads. If so then the choice seems obvious to me. Either way I'd like to have my heads flow as well as absolutely possible to support other companion mods and future mods.

What are the odds that I'll need new valve guides? If the chance is high how much would I benefit from oversize valves? Is it worth the extra couple hundos to get the oversize valves or should I skip it?

What is the largest cam thatll fit? 262 intake duration? How large for exhaust? Max lift?

Intake manifold-any nice aftermarket ones out there less than $500? Would prefer to not lose a bunch of down low torque either

Is there anything tricky involved with pulling the engine out? Should I leave the trans attached when doing it?

IF okay IF I can get a 5.4 from picknpull for under $200 which as far as I can tell is entirely feasable...why not? Is it not 100% plug and play other than just slapping the 4.6 oil pan on it and figuring out the intake situation with either spacers or special hood? Oh yeah and something about the 8 bolt flex plate...cant I just snatch up a specific torque converter from the junkyard?Please tell me it's that simple.

Speaking of torque converters if I stick with the 4.6 can't I get the smaller(11.25 inch, correct me if I'm wrong please) torque converter from basically any Police interceptor that's newer than mine? There's plenty in the junkyards. How high can these handle revving up to?

I will obviously need a tuner...right?? SCT xcal4 still the king with these old modulars? I plan to have it dyno tuned rather than mail tuned and wouldn't mind spending extra money on a better tuner if there were any measureable benefits. Do I even need a tuner at all still if I'm getting it dyno tuned?

I'm sure I'll remember more questions at another point in time but for now I think that's all I got. Please let me know if you have any answers to these questions. Also let me know if my goal of 300whp is ridiculous or what. Thank you all in advance.

#4076052 - 08/30/20 03:39 PM Re: Rebuild questions [Re: BigAl281]
Lance01 Offline

Registered: 04/02/18
Posts: 389
Loc: Pa
Personally I would just fix whatever is causing the oil and water to mix and avoid doing anything else that you mentioned. At 112k miles she's just a baby and you have many years of trouble free driving provided that you do the proper maintenance. 4.6 don't make a lot of power but they're very durable and reliable.

As far as upgrades the Jmod and rear end gears is the best bang for your buck if you're looking for more preformance. 88grandmarq on this forum sells and nice jmod kit.

I have a 04 police interceptor and I can tell you that she is still a dog meaning that she isn't a go fast car even with all the upgrades compared to your car. She does shine best in high speed freeway cruising.

Anyway, I'm saving you the hassle from doing all that work and you're still going to only go like 15-16 seconds in the quarter Fix the slush box and get 3:73 or 3:55 gears.

You want to go fast in a Ford get a Mustang such as a 03 Cobra. Panthers can go fast too but they need to be highly modified and supercharged ($$$$).

#4076056 - 08/30/20 04:23 PM Re: Rebuild questions [Re: BigAl281]

Registered: 08/05/13
Posts: 41
Loc: UA

Edited by MIHAYLA (08/30/20 04:24 PM)

#4076076 - 08/30/20 11:11 PM Re: Rebuild questions [Re: BigAl281]
BigAl281 Offline

Registered: 05/19/20
Posts: 15
Im planning on putting in 3.73s or 4.10s on it within a year. I know that alone will make the car much faster. I havent looked into the availability of t45s or tr3650s at the junkyards yet but I suspect I probably wont find one...still they have em on ebay all day long for under $1k if I remember right plus they'll probably need some extra love and cash put into them. If my money is right when the time comes id like to do the 5 speed at the same time as gears. Ive already read up about all the extra bits ill need like the aluminum driveshaft w/yoke, a clutch pedal from pierre, etc. If I dont end up doing the 5 speed though Ill Jmod her next time I change out the tranny fluid at 140k(just gave her the first change at 108k, service plug still in the pan).

Before this car I had a 2005 lincoln LS with 280hp and 3.55 gearing, under 7 second 0-60. So I realize that my grandma-rquis will never be "fast" but I want it to at least be as fast as my old car. And even if this lessens the reliablity a bit...idk if you've ever read up on the lincoln ls but lets just say that between 140k and 180k miles that car racked up over $10k in repairs(was still paying shops back then) and lost $3k in value by the time she was pulled away to the junkyard.
I do appreciate the input though. I know the panther platform is still a dog even with lots of mods. I cant help myself though. I dont believe I have an oil cooler so that leads me to suspect a blown head gasket. I could be wrong but rather than properly diagnosing it I think ill take the excuse ive been looking for to tear apart the top end and give er a few extra ponies while Im at it.

I guess Ill try to narrow down my questions to these:

-Will a set of ported NPI heads, PI intake, a set comp262s, and 3.73/4.10 gears make this dog faster than my old dog? I know 300 horses at the wheels is very bout 300 at the crank is that more realistic? I cant take getting beaten by any more prius's and camrys. And Im doing gears but I want more power too.

-Am I missing anything about the 5.4 swap? Figure out the oil pan and oil pickup tube, decide between 5.4 intake w/modded hood or 4.6 intake w/spacers, and change to the 8 bolt torque converter?

Basically I have a couple grand and I want some extra power under the hood. Yes im eventually doing the gears and ill mess with the tranny and Ill put on some better suspension and maybe brakes and eventually tires. But for now its as simple as I have money and I want mo power.

Again I appreciate any and all input.
"I wanna go fast!"
-Rick Bob

#4076126 - 08/31/20 03:29 PM Re: Rebuild questions [Re: BigAl281]

Registered: 08/05/13
Posts: 41
Loc: UA
I'm afraid the forum conversations won't give you enough experience. Enough to satisfy your ambitions. Therefore, it is worth studying someone else's experience or buying a finished product.

#4076154 - 08/31/20 07:27 PM Re: Rebuild questions [Re: BigAl281]
bluejay_32 Online   content

Registered: 08/28/16
Posts: 8179
Loc: wny
You'd probably get better answers in the Modular High Performance section than in 4.6 Powertrains.

Edited by bluejay_32 (08/31/20 07:28 PM)
2008 Grand Marquis - bought 7/29/16 - 60,210 mi
Inaugural CVNw POTM - December 2018 slug
CVN POTM - February 2019 joy

Originally Posted By IPreferDIY
Sounds like time-wasting gossip to me.


Who's Online
5 registered (ChrisM_NY, StankBacon, bluejay_32, Svtmedic, 1 invisible), 45 Guests and 304 Spiders online.
Key: Admin, Global Mod, Mod
Email Login
EMail Login Name
 New users, sign up!
Top Posters (30 Days)
bluejay_32 226
Old_Guy_Stu 120
a_d_a_m 99
DudeAbides 91
Ponyguy 72
CrystalPistol 45
Moby_Vic 44
Davidzq 43
ClayBelt 43
Bangster 37
Member Spotlight
Member Since: 12/28/10
Posts: 227

Copyright 2000-2015 by and Steve Spaulding. All Rights Reserved.
The photographs, graphics and data contained in this Web site are the properties of the contributors, or and may not be used without expressed written consent. is not affiliated with the Ford motor company.

Happily consuming the fuel saved by Prius owners!