1992 Mercury Grand Marquis

[pivichot]

I believe I have introduced my 1992 Mercury Grand Marquis before but I am gonna do a 302 swap in it and would like to give a history of it before.
I bought this car on October 10, 2010. It had a damaged AOD transmission, the usual TV cable. I bought a used AOD from craigslist for about 60 bucks. Used that to rebuild mines.
Here is a picture of when I bought the car.


The transmission was rebuilt with a haynes manual. Although it is not the best I also used a video series from youtube from the user bah53 to get an idea on how to rebuild it. The car had several problems so I had to fix that and the paint was also damaged. So I decided to go with rustoleum flat black. I was quoted 3000 for a gloss black paint job and being this was a 700 dollar car I didn't see it as being worth it. So rustoleum was just 30 dollar a gallon and it couldn't get worst.
The fender had to be replaced since they were rotted at the bottom.


After That I decided to put a basic car alarm since after I painted it someone scratched the paint with a piece of stone. That was at my Highschool. I got angry.


Recently I just replaced my stock 15 inch rims with 16 inch interceptor wheels or the basic wheels for a crown victoria. Also I used Mountaineer hub caps.


So, finally after a year I am starting to save up since I need to repair other stuff on the car to finally replace the engine and drivetrain.
1.For the engine I will be going with a 302 engine. Would go with a 351 but fuel mileage might be an issue. So I am planning on upgrading cams, Intake , Ignition, and exhaust. But right now I am not sure if I should search for a used engine and build it or just buy a new one. I want to leave this engine ready for in case if I just want to supercharge it or put nitrous.
2. For the transmission I will use 4r70w parts to increase the ratio. But will also change valve body to make it be able to change gears manually. I know I could go with a manual but I do city driving and I don't want to worry about changing gears and pressing the clutch. So I am going to prep the AOD
3. Rear differential I will go with either 3.55 or 3.73. 4.10 will not be a good idea since it will accelerate faster but will be limited to a certain amount of speed. will also rebuild the differential completely.
4. For the ECU I will megasquirt in case If I ever want to tune it for supercharging it.
5. I will upgrade the front suspension with 98+ parts. The rear brakes will be replaced with vented brakes and new brake lines will be installed.
There will be more updates to be done. But now the collection of parts begin. Every time I buy these parts I will post. This won't begin until around September or October. But I am finally beginning to do it.

[sly]

awesome. Another 5.0 aero!

explorer engine is the usual cheap way to do it (upgrade parts in that as needed like valve springs and swap in an HO cam). if you can find it, the 92 t-bird engine has the cam stamped GT that was used in the cobra (this is also a good swap in part on the explorer engine). Other than that, sky's the limit with new engines.

[pivichot]

I already know I will have to buy a 86 or more modern engine. Now the question is whether I should buy a new long block or buy a used engine from a junkyard to rebuild. There are a lot of things I want to do but I also have to go with suspension, differential, and transmission. I know that now in September I am most likely buy 600 dollar in parts. With that I know I can find a used 302 (to rebuild) and several other stuff such as 98+ suspension. Are forged internals good for a daily driver? I want to build the engine well, so if in the future I want to either add nitrous or a supercharger so it can withstand it. Also are there basic performance mods beside the gt40p heads? I am planning it to take it once every month or two to the local drag strip just to run it for fun. I will also port and polish the heads while rebuilding the engine.

[sly]

it all depends on your budget and how much you plan to do yourself. crate engines start around 3 grand for a long block and go up from there. The 306 (bored and refreshed 302) is probably the best bang for the buck in a "new" crate engine format. If you're lucky and can find a 92 thunderbird and get that engine and it's not totally whipped, that would be the best bang for your buck period because it's a junkyard engine. But you'll probably need to give it a good teardown and refresh yourself.

as for forged internals, they are pretty much required if you plan to boost or spray much at all. Stock setups can usually handle a 100 shot or 6psi of boost for drag strip runs, but if you do lots of runs in one day or take it to a track day, you may be in for trouble as the non-forged pistons may not end up in good shape. Also, the block will need reinforcing if you plan on pushing more than 400hp IIRC, and is generally a good idea for anything over 350hp on a stock block. Dart blocks don't have that issue, but they're kinda spendy.

Now if you're planning to build it up yourself... an explorer GT40/GT40p is a good place to start. You can generally get 300hp easy out of those with a good port and polish and decent headers/exhaust and tubular intake. Mass air setup tends to work better, but with tuning, speed density can handle it just fine. and with an aggressive tune, you might see as much as 350hp natural (may require 24# injectors if it leans out at higher RPMs).

It all depends on what you want to achieve in the end.

[88Vic]

You can use an 85 block as well, if you can find one, the 85 GT 5spd had a roller cam and was slightly bigger than the 86-95 cams. A buddy of mine has an 85 GT enigne in his 2 door Fairmont, and with headers, 2.5" exhaust and Flowmasters, you can hear the cam lope a tiny bit. You'd be better off just getting an E cam though, not too big so it's still got some low end to it and more top end than stock HO cam. If you don't care about top end the stock Explorer cam is great for daily driving.

[pivichot]

well, my budget is around 4000 to 5000. It can be seen as my first project car. I am planning on first going with the front suspension since either way I will need ball joints and tie end rods within the year. So that would be around 200 at the local junkyard or less plus other parts such as brake calipers and bushings. I am planning around 400 on the front suspension plus alignment. The transmission I have rebuilt it before but now I am going to do use the 4r70w for the wide ratio plus a manual valve body. That I am planning to be max 1000. The rear differential Will be new gears which are less than 200, new axle and bearings while I am at it, but also want to put a trac lok in it. Around 600 for the differential.Those are around 2000. I will need a new fuel tank because it holds too much pressure. Also while I am at it will replace fuel lines since mines are almost rotted. Also new fuel pump. An ecu and MSD 6a box whill run around 500. I am going to do my own wiring. then afterwards the engine. The engine will be the last thing since I have no space to keep a block. Once I have money saved then I will buy the engine. Also I will need to do new brake lines. IT is a long project which I want to complete if possible within two years. I mean I could also do the swap first with an engine from a junkyard and then build that one and go from there. Right now I am researching more information about the megasquirt ecu because I want to keep sequential injection and not batch fire.

[pivichot]

Quick question. How much can a stock crank hold in terms of power? Because for less than 1000 I can prep a short block with forged piston and connecting rod while keeping the stock crank shaft. I am planning to running max of 350 hp is possible. I won't go with a 100 shot of nitrous. It would be 75 or less and only for drag racing once every two months.
Also any suggestions on camshafts? Which would be a good one for a daily driver? I know that an explorer cam. But any other that I might look at? Edelbrock maybe?

[MrMarquis]

I like the flat black with red rocker panel trim. Looks good together!

[sly]

stock crank can handle about 400 IIRC... the cast pistons... not so much... the block ... maybe... 350 is the safe zone for sure. Though 300 would be safer if you plan to spray. 351 based swap would be much better for anything in the 400 ballpark (350 base and 400+ with spray). The block just works better.

[pivichot]

Should I stick with an Automatic or go with a Manual transmission? because I know that an automatic steals hp because of the torque converter.

[gadget73]

your call. Can you drive a stick and are you willing and able to do the work to convert it? Would the manual make it more of a problem to actually use the car? Little point in changing it all over if you'll end up not driving the car because its annoying for you to deal with. If you have a working transmission now, I'd run what you have and convert it later if you want to. Makes it somewhat easier to do only one major project at a time. Putting a 302 in is enough of a project. No need to complicate it further right now.

[pivichot]

Well my plans are to first rent a car with a manual transmission to see if I would like to convert it. Never driven a manual but my mother actually knows how to so will most likely learn from her. I want this to be a fun car to drive. Not saying right now it isn't. I use this car to drive to my college. I driver early in the morning and late at night. Rarely will see any traffic jam. Not saying it won't happen. I will be willing to do the work. I would do the whole project in a summer. What I mean by that I will install everything in 2 and a half months. I will actually go prepping everything up before the summer then. I could go doing everything at a time and if I want to do the swap wait until the AOD goes out. I would most likely do everything to get all the wiring out of the way and route everything correctly. Reason being that If I want to go with a manual I need to be careful if the exhaust gets in the way.
Also now the car, the ac stopped working. The system is brand new. It seems to be the variable orifice tube since it is still full of gas but not cooling enough. The refrigerant is not low and I don't believe it is the compressor. Will be taking it to a shop to have if evacuated so I can fix it tomorrow or Friday. Will be replacing it with a fix orifice tube.

[pivichot]

Which are the manual transmission which can fit the small block configuration? Is it the T-5?

[sxcpotatoes]

Yep, T-5 is the way to go, I've seen those with unknown history going for around $250 here on CL.

[pivichot]

I guess I have a problem with the AC. I believed it was the orifice tube and it seems to have been clogged. The Ac system I personally installed it with the oil required and all new parts including evaporator and condenser and brand new lines.