5.0L Upgrades.....Best bang for my buck(or two)!

First of all, I know a lot of you are going to laugh when I tell you what 5.0L vehicle I would like to ‘upgrade’. Are you ready.......................It's a 1988 Grand Marquis Wagon (aka Colony Park) with the 5.0L engine, go ahead I know HaHaHa. But anywho, I'm assuming that the motor in both my wagon and the mustang of the same year are somewhat similar with more performance going to the ones in the mustang. Does anyone know the differences? If not it's no big deal, I was just curious.

Now I'm not looking to make this into a 10 second drag car or street sleeper by any means. I'm just looking to get a little extra power out of it without going nuts on it. I use it for towing all kinds of stuff and load it up with any number of things, sometimes while I'm towing. I've come to like it quite a bit despite all of my friends constantly giving me, a 23 year old, crap about driving a 'grocery getter', but it suits me well for what I do. It also has some sentimental value as I purchased it from my grandfather (who is no longer with us) who gave me a deal I couldn't pass up. I hope you get my point because I'm expecting to get flamed big time on this for posting it in a mustang forum. The Grand Marquis forum was looking a bit........well....... sleepy, which didn't surprise me so I came here. (No offense Grand Marquis people!)

Some of the ideas I had were: headers, dual exhaust (remove cats?), adding a mass air meter, different intake plenum, performance chip, you know 'bolt on' stuff like that. Things that I could find used but still do the job, cause I'm not looking for a show car (or wagon) here. If I'm nuts for trying this because I won't tell the difference in performance even if I do all this just let me know. That's why I'm posting it here before I do anything and I figured with all the mustang parts around, especially for the 5.0L I might get away somewhat cheap. I can do all this work myself so it's just the parts I need to buy.

Any information would be much appreciated!

Thanks,
Justin

MY 2 Cents, i would do what everyone does to any car they want to go faster. Ya know, get some better flowing mufflers, have a muffler shop bend you some tubing to match your car. After that weld it up, and look towards the intake side of your car, go to home depot and get some metal tubing (you know that stuff they use on clothes dryers, it is flexible and tolerates some heat) and slap that on with some cone filter as an intake. Who knows what that will get you in terms of power but atleast it will sound better, and have somethin shiny under the hood...LOL.

GEARS! I don't know if this a feasible upgrade for your particular car, but it's a popular upgrade for stangers, give's the best bang for your buck according to 99% of people who get them, it's my next upgrade... Another would be underdrive pulley's. I'm not sure if they'd fit right, but they're cheap and give a small noticeable gain (Maybe I just wanted to feel faster.)

im not sure if gears would fit him, of course they would make you go faster especially when towing, but with all that extra towing weight and the high rpms youd be cruising at, you wont get very good gas mileage.

Actually I think gears would suit him ver well, even with the towing. The extra torque from gears will help get ALL that weight moving of his car and the towed vehicle. As long as he doesn't go too steep like 4.10's he'll be fine with something like 3.55's.

I never thought of gears? Does anyone have any clue what's in there from the factory? If I would change them what is the 'tallest' gear I could go to with still being able to take it on the freeway on long trips(70-75 mph)? I know you cant have it both ways but what would be a happy medium?

Thanks,
Justin

Evem with it being auto you seem like you want more than bearable highway gearing I'd go 3.73.

gears, exh.,pulleys

I dont know a whole lot about late '80s Mercs, but I suspce it has a no-HO engine in there, meaning something like 180-200hp, non-HO firing order, cast pistons, etc. A decent upgrade would be an HO '87-93 Mustang engne. If thats too much for now, then consider gears as they will probably make the largest initial improvement with such a heavy car. The common concensusamong 'stangers is 3.73s minimum for an AOD transmission and 3.55-3.73s for a T5. Wat you choose depends on how much highway driving you do and how much perfprmance you want.

Remember that question about 'what does my 5.0 have for output’; you guessed it I had to find out. Like speedfreak said, 180-200 hp is what I would have guessed it to be. After much searching I have concluded that it's only got about 150 HP and 230 FT/LBS of torque. I can't be driving something that weak!!! Although I must say for having only that much it does pull pretty hard with a full load, but you can never have enough......HaHaHa

If, I was to get a mustang motor in stock form what is the year and model to look for and would it bolt in for the most part? I can see where this is going for me, so much for the bolt on stuff.......

Thanks,
Justin

If, I was to get a mustang motor in stock form what is the year and model to look for and would it bolt in for the most part? I can see where this is going for me, so much for the bolt on stuff.......

Thanks,
Justin

Any of the years I mentioned. If you dont mind hypereutectic pistons, then include the model years '93-95. All 302s from 1968 to 2001 or whenever they stopped producing them, not including the Boss 302, are interchangeable and have interchangeable parts. Same bellhousing pattern, and engine mounting points. '87-95 make 225hp factory with lots of room to grow. With that heavy car and towing in mind, you might at least consider a 351W or a 351W based stroker(which will also bolt to the same engine mounts and trans as a 302, but fit is another story).

That or a 460....

I think the 460 would be going way too far, but would a 351W out of a truck bolt up to my trans? What was the output of the 351W, because I just got done putting a steering column in a 91' F250 with the 351W and it hauled some pretty good tail when I took it for a test drive? If I would go that route are we talking computer and wiring harness swap?

Thanks,
Justin

OK I just found a picture of a 5.0 out of a mustang GT and why is the intake turned 180* compared to my setup? Might that be a problem?

Thanks,
Justin

I think the 460 would be going way too far, but would a 351W out of a truck bolt up to my trans? What was the output of the 351W, because I just got done putting a steering column in a 91' F250 with the 351W and it hauled some pretty good tail when I took it for a test drive? If I would go that route are we talking computer and wiring harness swap?

I just mentioned the 460 jokingly. It would be a really in-depth swap needing either a C6 trans or an adapter for yours(which probably could not handle the big block torque). It would definitely move, though.

Since you have a 302 already, yes a 351W will bolt up in place of it. It is a little taller and a little wider than a 302, so you would have to make sure it would clear shock towers, steering columns, and brake boosters. I'm unsure of the exact output, but I do know they made alot more torque than a 302. It sounds like you want to keep the EFI and that poses some challenges. It will help if you convert to mass air, but using electronics on a 5.8L that are programmed for a 5.0L will probably still require either a chip or reprogramming of the ECU. A Mustang's engine will still be easier, which brings me to the post below the one I quoted;

Dont worry about your upper intake opening being pointed att he driver's side in relation to a 5.0 Mustang's passenger side. The bolt pattern is symmetrical and you can turn the Mustang's intake around to fit your car.

I was hoping you could do that, now all I have to do is find a mustang motor. I'm going to pass on the 351W idea although it would be pretty cool combo; it's just a lot more than I want to do. Besides I can't find anyone that has attempted something like that with a car like mine and don't feel like trying, a mustang is a different story. I think the mustang 5.0 will be more than enough power, especially if I do all the bolt-on stuff. I'm having the transmission rebuilt real soon and I'm wondering if the mustang and the marquis differs at all, I'm guessing yes. Where can I find a GOOD mustang motor with decent miles on it? I did find one on e-bay with 77k out of a 93' GT. Besides the pistons, which I don't think will matter in my case, is there anything else I need to look out for?

I really appreciate all the info you've given me so far, I've learned a lot (+8

Thanks,
Justin

I was hoping you could do that, now all I have to do is find a mustang motor. I'm going to pass on the 351W idea although it would be pretty cool combo; it's just a lot more than I want to do. Besides I can't find anyone that has attempted something like that with a car like mine and don't feel like trying, a mustang is a different story. I think the mustang 5.0 will be more than enough power, especially if I do all the bolt-on stuff. I'm having the transmission rebuilt real soon and I'm wondering if the mustang and the marquis differs at all, I'm guessing yes. Where can I find a GOOD mustang motor with decent miles on it? I did find one on e-bay with 77k out of a 93' GT. Besides the pistons, which I don't think will matter in my case, is there anything else I need to look out for?

I'm not sure, but the '80s fullsize Ford assenger cars might have been available with a 351W...

If you think your Merc is peppy with 150hp, then a 75hp boost from a stock 5.0 HO should make you really grin. Full exhaust(2.5" with headers), a good air filter, 73mm+ MAF, and 65-70mm TB will get you somewhere around 20-25 on top of that. As far as the transmissions go, I dont know what the Merc or if its the same as a Fox3 chassis's AOD. With an engine out of a 'stang, you'll need the computer too(if for no other reason than to do the mass air swap), distributor, and snagging the flexplate and torque converter wouldnt hurt provided they will work with your trans. As for getting the engine, look locally first. Dont get one covered with dirt and oil. From my experience and observation, the dirtier a 5.0 engine is, the more miles or abuse it has seen.

Another consideration is an enigne out of a '96-2000(2001?) V8 Exlorer. They already have GT-40 or GT-40P heads and the equivalent to a Cobra intake. '98+ engines do not have EGR passages, so keep that in mind if you have emissions testing.

What does the 'p' stand for after the the GT-40 notation. You were right about my marquis coming with a 351W, I found one at a boneyard, but I don't think the made too may of them. Too bad the intake had been taken off and rained in for years(Rust in Pieces). Do you know what the Exploders were rated at?

Thanks,
Justin

It was actually a Country Squire(same difference) that had the 351W but it was earlier 80's.

I dont know what the P stands for, but I take it to mean that you'll need to have Thermactor holes drilled(if you want to stay 50-state legal) and special headers to clear the sparkplugs(none of which are smog legal). Regular GT-40 heads bolt on in place of nearly any 302 heads with pedestal valvetrain whereas the GT-40P will bolt on, but need the special considerations above.

The 96-97 V8 Explorers have GT-40 heads while later than that used GT-40Ps. They were rated around 210hp @ 4600rpm, but that is largely due to the cam. Put a Mustang or nearly any aftermarket cam in there and you're looking at a 40-60hp gain.

Is that what you were getting at earlier in the post when you mentioned about the EGR valve delete. As far as the emissions I have it titled in a non-testing county, (shhhh don't tell anyone!) So emissions is not a concern. I actually looked at a 99' Exploder 5.0L this morning when I was at the boneyard, but I lost interest when they wanted $1,400.00 for the motor w/ 37k miles. I think I'm just going to take it slow and see what comes my way. I'll let you know if I come across anything.

Thanks again for all the info!

Thanks,
Justin