New Guy. 1991 LTD Crown Victoria

[westernmcd]

Hello all. New user of the site. I have been looking for some reliable information on upgrading a 1991 LTD Crown Victoria from a complete turd to something a little more fun to drive. Was my grandmothers car, 80K miles always garaged and never driven in the rain. It still looks brand new. LOPO 5.0 150HP and 2.73 gears, good gas mileage and smooth ride, just lacks power. I am not looking to get crazy and build a 12 second car, but would like to gain 75 ponies if possible. I know the HO 5.0's of that era were around the 225HP mark. From what I've gathered from some research, the main difference between the HO and LOPO is the heads and camshaft and these can be swapped out of a Lincoln Mark7 or Mustang of similar vintage. I have noticed that the Intake and throttle body are reversed in these cars compared to the Crown Vic and swapping those looks to be a pain.
Is there any difference in the intake? Can I use my old one and upgrade the throttle body only?
Are the E7 heads and camshaft out of a HO motor a good choice? I get the impression they are easy enough to come by at Pick-a-parts.
I understand that an ECM out of a Lincoln Mark 7 would need to be used and it would keep the cruise control function on my car.
I looked into having my rearend rebuilt with Limited Slip and 3.55 gears. Pricey, around $1400. I can cut, weld, fabricate most anything. If I can't find one that is compatible, changing spring/shock mount locations is no too big of a deal. Are there other stock rearends that are the same width/bolt pattern with a more favorable gear ratio? I'm not opposed to changing to rear discs, but would rather not.
Tranny shifts at pretty low RPM's, is there an easy upgrade to the AOD to improve?
Spoke with a gentleman at an exhaust shop and he was trying to talk me into a Y-pipe back, 2-1/2 single exhaust as opposed to duals. I'm thinking I want to find some headers that work and do a complete true dual exhaust.
I have money, but not looking to spend my retirement on building a hot rod out of grandmas car. I see myself being able to justify around $2500-$3000 for upgrades.
What are the items that are the biggest bang for my buck?
It runs perfectly right now, hard to tear into something that isn't broke.
Are there bolt-on upgrades that improve performance? Not finding any CAI's advertised for this car, what is compatible?
Any merit in the six-liter tune up I've read about? Is that something that would even make a difference before HO upgrade?
Long-winded, I know, but any advice I can get will be appreciated.

[DerekTheGreat]

TLDR: Sell it and buy a '90-'92 Lincoln Mark VII LSC.

Like you said, it's hard to tear into something that isn't broken and that is exactly the spot my '88 Town Car is in. I originally bought a wrecked '91 Mark VII to swap into my Townie and well, I ended up fixing and keeping the VII cause they're cool That and I couldn't fathom the idea of making my Townie into Frankenstein's monster.. 1/42 made like it in 88..

However, if you must go there then yes, just either swap an HO from 87 & up in there or use your block by swapping all the stuff over. Bullet points:

-The pistons are different though. Believe HO equipped 302's got flat tops while we LoPo's (NoPo) got dished stuff.

-The intake will need to be reversed and you'll have to have your EGR spacer bored out to 60mm and swap the throttle linkage from a NoPo throttle body over to an HO throttle body. Actually, 87VIC (David) is selling a few Lightening spacers & TB's with panther linkage and those will work.

-NoPo & HO lower intakes are the same. Uppers are different, NoPo is 40mm, HO is 60mm.

-You will need the Mark VII computer for sure.

-Might even need to swap the fuel pump which is a chore I've heard, not sure the NoPo fuel pump will keep up.

-You can swap a disc brake rear end from a 92-97 panther in with minimal work, if it's a K code it'll have 3.55's and posi. Might need to be verified on the year and K code from some other peeps on here.

-As for the slushbox, you need the valve body (or is it just the governor?) from a Mustang or maybe even a Mark VII if they're the same. Probably are since HO status. Needs to be verified by senior tech members here though. I do know Lincolns have longer tailshafts than Mercury or Ford transmissions.

-I am not aware of simple performance upgrades. Biggest bang for your buck will be the rear end. If you want, you can just do the upper intake & TB swap to HO stuff. Heard it improves throttle response and what not. I have stuff to do it, haven't gotten around to it as I need the EGR spacer yet.

-Use 1990 Lincoln Town Car air box in place of crappy '86-91 Ford unit.

-Welcome to the site. I'm pro box and like to see more box people one here

[VicCrownVic]

Welcome!
Not too many members out on the west coast, but you have come to the right place.
My personal knowledge on the upgrade subject is quite limited, but I have to throw in.
Those more knowledgeable will be along soon (not everyone is on here everyday; give 'em a few days and you'll be flooded with info).

...
-The intake will need to be reversed and you'll have to have your EGR spacer bored out to 60mm and swap the throttle linkage from a NoPo throttle body over to an HO throttle body. Actually, 87VIC (David) is selling a few Lightening spacers & TB's with panther linkage and those will work.
...

^Yeah, all the work has been done for the TB that 87gtVIC has; good option.

...
-Might even need to swap the fuel pump which is a chore I've heard, not sure the NoPo fuel pump will keep up.
...

^Since he has a '91 CV it really isn't bad compared to the pre '90 boxes. You should be able to swap the fuel pump without dropping the tank on a '90+, and the higher output pumps are the same physical size as the stock pump so the stock hanger can be used. I couldn't tell you if it's needed though.

...
-Use 1990 Lincoln Town Car air box in place of crappy '86-91 Ford unit.
...

^That or I believe the air box and tube off of some of the Crown Vics made during this century have larger diameter tube and inlet on the air box. 87gtVIC, as well as a ton of other members can shed some light on that topic.

That about exhausts my limited knowledge. Lets see some pics!

[DerekTheGreat]

...That about exhausts my limited knowledge. Lets see some pics!

Limited knowledge my ass! Your humility is commendable though.

[87gtVIC]

The intake being on the other side is no bother. The stock upper for both the HO cars and your lopo will fit either way. Its all of the throttle, and TV linkage stuff that determines which way the intake faces. You can without any issue swap on a mustang HO upper intake (87 and up Mustang…has a H.O. stamped under the intake plenum plaque) onto your lower intake. What you run into with that though is EGR spacer and throttle body issues. The mustang stuff WILL NOT swap right on. Our EGR spacers have special mounts where the throttle linkages bolt up to that ARE NOT present on the mustang ones. Kinda forces us to bore out the stock spacer to match larger intake/throttle body. OR pick up a lightning egr spacer which already has the proper mounts for the throttle linkages to bolt too. The throttle bodies from mustang/similar will also NOT bolt right in place. The actual throttle linkage arm would need to be removed and swapped for one from your vehicle/similar panther.

I do not see any gain by just upgrading throttle body.

If you can find e7 heads already rebuilt and for cheap I would put them in with a stock HO camshaft. Otherwise I would get some GT 40 heads. I went straight aluminum heads so I don’t know much about the gt40 versus the gt 40p heads.

I cannot comment about cruise still working or not. I have an 87 crown vic which has a standalone cruise computer so I kinda got lucky and did not have to learn about how to retain cruise.

You can swap in mustang hi rev governor. That will raise the shift points. ONLY do this if you go full HO. Otherwise the engine will wind up for no reason.

I too would go full dual exhaust.

Don’t bother with a cold air intake set up. Just pick up an air box and zip tube from any newer crown Victoria. Couple that with a 1990 Lincoln town car radiator shroud and coolant overflow tank and washer fluid reservoir and you will have more than enough air.

[sxcpotatoes]

Go full dual exhaust but maybe don't go true duals if you're going with louder mufflers like cherry bomb glass packs, you want/need that x-pipe or H-pipe crossover or it can drone like a MF at certain highway speeds causing inner ear interference and dizziness even!

If you're doing all the work yourself your budget is very reasonable, but it may be easier just to find a GT40 motor from an Explorer/Mountaineer, put on BBK headers and a tune you can approach 275-325 easy. Properly set up rears can be expensive, but you can directly swap in a '92-'97 disc brake rear end with the gear ratio you want already installed and do the front big brake upgrade too.

My first car was an '88 LTD like yours (highway gears etc). I didn't know about the better performance steps so I did true duals with glass packs and 1000w stereo w/4 12" speakers, kept it to 55mph and got 28.5mpg on a 424 mile trip down to visit family in WV down and back on the same tank of gas. More power and better gears will almost always mean less gas mileage though, once you start messing with it dependability can go out the window for awhile too so hope you have a backup vehicle.

[sly]

+1 dual exhaust, 3.55 limited slip rear.

That by itself will make it a demon from a stop to about 35mph. If you want midrange to high end, you'll have to do the cam swap and better upper intake/injectors and switch to a MAF computer (add 3 wires to the computer to add the MAF IIRC). Explorer intake, Explorer cam, Cobra cam, or similar (I think the preferred one around here is the XE258? and you'll need the roller version) with power range from about 2000-6000 and some GT40 heads with good valve springs and you should be up in the 270 or so hp range.

Or LS swap it

[westernmcd]

Just ran into a gentleman at work with a motor and trans out of a 93 T-bird. Said it was a runner when he got it about ten years ago for a Mercury Cougar build project that he went another direction with. It's all there, motor, trans, wiring harness and ECM. He wants to clear up some room in the garage I can get the entire shooting match for $300. Seems cheap enough to acquire some HO parts plus a tranny as long as it will work out. Told me it has E7 heads, HO cam, HO intake. He also said he has some orange top injectors I could have. He wasn't certain about needing to replace the fuel pump, but thought it was a good idea.
He also recommended finding some headers and going true dual exhaust.
Is it worth putting some time and money into this T-Bird motor and swapping the entire thing into my car?
Better off to salvage the heads/cam/intake, have the heads ported/polished, rebuilt and install on my motor?
Still a little confused on the intake. If It is reversed, with the air inlet on the passenger side, it will run into the AC tubing. If I am understanding 87GTVIC, the lower is universal and the upper can be installed either direction?
Is there any issue with the T-Bird intake working?
I'm in absolutely no hurry, mostly because car runs and drives very nicely.
I want start where it makes the most sense and it seems that the rearend gearing is the best place.
Already replaced the stock rims/hub caps and 20 year old whitewalls with some 17" aluminum rims and 235/55/17 tires. Ordered neutral offset rims so the tires fill the wheel wells out a bit more.
Replaced all the shocks and had the shop look at all the ball joints/tie rod ends and wheel bearings. Everything is ship shape and brakes are good so I can start in on making more power.
I will get some pics up as soon as one my kids comes home from college and shows me how.

[gadget73]

Mark VII ECM from 88-92 is integrated cruse. It will retain the cruise on a 91 with no problems.


Don't bother with the Tbird wiring harness, use the factory one with a Mark VII ECM. It fits and works with no modifications at all. The Tbird wiring will not lay right at all.

93 Tbird motor I think has the stupid bendy upper intake. Swap that for a standard one and it fits in there like a glove. The bendy one won't reverse. The regular HO one reverses no problem. If you don't spin it, the air intake stuff is into the AC plumbing and the battery is in the way. It just doesn't fit in there nice at all. If you put it so it looks like the factory motor it all lays in there neat as you could want.

Stock fuel pump will work fine.

[pantera77]

Just get an Explorer/Mountaineer engine, HO swaps are a waste of time

[gadget73]

Fair point. Explorer heads and intake are far better. 93 Tbird motor should have the Cobra cam which is actually a lot better than the HO stick in a heavy car. Cam from that engine + Explorer motor with better valve springs makes a fine combo. Or stuff Explorer heads and intake on the Tbird motor, whatever you prefer. Either way the HO heads and intake have absolutely no special qualities. Sucks less than the stock stuff but it still sucks.

[Mainemantom]

Unless your transmission is bad, don't use the T-bird transmission. 93 was not a good year.

[Rodentkiller]

Do yourself a favor don't even try to hot rod your CV what you have is a very comfortable car not meant to hot rod. You do not need the headache just enjoy the car, I own one and I enjoy the comfort of the car I speak from experiance being the former owner of a stock hot rod, I could not drive that hot rod out of the county until the transmission went kaput and i junked out the car. Instead spend the money on a killer sterio system and have a ball when you can stuff six friends in the car to go for a cruse.

[westernmcd]

All good info.

[DerekTheGreat]

Yeah I keep forgetting about the Exploader motor... Would a Mark VII computer run that with no issues? Can't remember if they uses the 351/HO firing order too