5.0 build in 1990 Grand Marquis

[86VickyLX]

Ah, ok. You just want the car running now right?
Do you know what's wrong with it?

[1987cp]

If the goal is only to get it running and driving and there's nearly no money available to do so, then possibly the best move would be to get it going as cheaply and simply as possible (possible translation: fix what's wrong and leave it at that), and see what you can do for a performance build a few years down the line. Just a thought.

[N A]

"...Do you know what's wrong with it?

Yes, a few weeks after having the crankshaft bearings replaced, it let go on the highway at 60 mph. Every light on the dash came on, the motor died and I had a trail of 5W30 behind me.

I'll get it running again. I'm looking at possibly Spring or Summer 2012. I'm not rushing it.

[1987cp]

"having the crankshaft bearings replaced"? I hope that doesn't mean you tore the whole engine down and replaced only the crankshaft bearings ....

So sounds like the main thing is getting yourself a servicable shortblock. Thankfully, that's both cheap and easy.

[86VickyLX]

"having the crankshaft bearings replaced"? I hope that doesn't mean you tore the whole engine down and replaced only the crankshaft bearings ....

So sounds like the main thing is getting yourself a servicable shortblock. Thankfully, that's both cheap and easy.

I'm thinking crank kit.

And with the trail of oil, been there done that. Luckily I was able to pull over and shut it off with the engine still holding a half a quart of oil in it. Engine ran, but developed a knock, however oil pressure was fairly decent still.

[N A]

The bearings issue was on the 302 motor. I haven't found a 351 yet.

[1987cp]

If all you want is reliability, a rering on your existing engine might be the way to go ....... I reringed my '87 302 at 140k miles, and even with lots and lots of sitting, it's still in very decent shape.

[N A]

I want power.

[MjRock441]

Inexpensive Performance Upgrades

Hello, all. Just found this site and have been enjoying it quite a bit. I have a 1990 Mercury GM with the 5.0 power train. I've done the exhaust (No cats, low restriction mufflers), installed a cold air intake (Built from spare parts in the garage, complete with heat shied and small hood scoop). Had the AOD rebuilt a bit beefier than stock (It'll bark second at 3/4 throttle).

So, I have a couple of questions about the next inexpensive performance mod..... What about throttle body spacers and mass air flow sensors? Would modifying these be any help? I was also wondering if a hotter ignition would help at all. I plan on replacing it next anyway (it's the original) before it goes out, so what are the pros and cons of a hotter one?

The A/C doesn't work, so I removed that belt, as well as the exhaust recirculating pump belt.

Any other ideas? The budget is very tight.... but I would appreciate any input you guys could give!

Thanks,

Mj

[johnunit]

with a stock intake and heads, messing with the MAF doesn't do much. The ignition system (in good condition, new ford wires, etc.) is also pretty good stock.

I've heard mixed results on spacers.

If you can, I'd put on some headers (ideally aftermarket and paired with 2.5 inch exhaust). Anything shorty and unequal length for 79-95 mustangs will work, including the stock mustang headers, but you will need to modify the downpipes. The mustang headers don't quite exit where the stock panther manifolds do. You may also have to change the O2 sensor wires, but a more EFI-savvy person will have to fill in the details on that.

Do you know what rear gears you have? If it's not a limited slip (tag on the diffcover will have an L in the code) I'd look at adding that, and if your gear ratio is numerically lower than 3.27 I'd certainly look at getting higher numerical rear gears.


IMO the restriction point on these engines is (in order) low compression and poorly flowing heads, crappy exhaust manifolds, very mild cam. Then for the rest of your drivetrain the numerically low rear end gears and low stall-speed torque converter also hurt your get up and go.

I'd also not consider your exhaust "done" or optimized because you have no converters and some free-flowing mufflers. The 2 inch stock stuff is still a restriction, especially once you open other stuff up and if you have crush-bent replacement piping. Not a huge priority but something to consider.



Oh, and welcome to the site! I hope you enjoy it and stick around to post more pics and info about your car.

[1990LTD]

Will probably have to extent the o2 wires. Not a big deal, just measure twice and cut once so there's not a lot of slack to let the wires burn on the pipes.


I don't know if a throttle body spacer will do any good. I know guys use 1/2" intake manifold spacers but I think the main benefit of those is heat dissipation though. I would install 5.0 HO upper intake/TB/bored EGR spacer If I were you, as a start. A MAF swap may not be necessary at this point.

[johnunit]

I think the manifold spacers (inbetween the upper and lower) are also for clearance for taller valve covers, no?

[86VickyLX]

Hello, all. Just found this site and have been enjoying it quite a bit. I have a 1990 Mercury GM with the 5.0 power train. I've done the exhaust (No cats, low restriction mufflers), installed a cold air intake (Built from spare parts in the garage, complete with heat shied and small hood scoop). Had the AOD rebuilt a bit beefier than stock (It'll bark second at 3/4 throttle).

So, I have a couple of questions about the next inexpensive performance mod..... What about throttle body spacers and mass air flow sensors? Would modifying these be any help? I was also wondering if a hotter ignition would help at all. I plan on replacing it next anyway (it's the original) before it goes out, so what are the pros and cons of a hotter one?

The A/C doesn't work, so I removed that belt, as well as the exhaust recirculating pump belt.

Any other ideas? The budget is very tight.... but I would appreciate any input you guys could give!

Thanks,

Mj

There's no exhaust recirculating belt. There's an air pump, but that doesn't do anything with exhaust gasses.

You don't have a mass air sensor (unless that car came from California).
Throttle body spacer? You could use an intake spacer. 1/2" will be the thickest you could go. Unless you mod the hood more.

Original sometimes can be better than aftermarket. TFI modules are one big thing that come to mind. Coil you could upgrade. Some 9mm Ford Racing wires.

As for engine performance, an HO conversion would be good. Heads, Cam, upper intake, injectors, and computer. Or better yet an explorer 5.0 swap.

[1990LTD]

I think the manifold spacers (inbetween the upper and lower) are also for clearance for taller valve covers, no?

that too! i have a 1" spacer that i would very much like to cut into 2 1/2" spacers

[86VickyLX]

that too! i have a 1" spacer that i would very much like to cut into 2 1/2" spacers

I don't know if that would work... Try it