So...someone suggested an HO swap. Worth it?

[ootdega]

Someone suggested an HO swap for my 89 5.0 EFI SO before I make any plans for a supercharger any time in the distant future. I've looked into it and seen the thread on it here, but I have some questions that aren't addressed there.

My first concern is reliability. The engine I have runs like a Swiss watch with zero problems and has gone vroom every single time I turn the key. I don't want to compromise that just for performance.

My second concern is efficiency. I was told it would improve mileage. I can see how that would make sense but I want to confirm this.

My third concern was going to be cost, but after a little Ebaying it appears I should be able to afford one part at a time without too much of a problem. Installation is another story.

So then I'd just need to know everything I'd need and/or want to do to make it work. So far I know I will need:

E7 piston heads
HO camshaft
HO throttle body
19 lb fuel injectors
63mm EGR
Swap throttle body linkage arms (I have no idea what this means)
Better intake

And I've HEARD I should also:

Convert the fuel injection system to SEFI. If so, how?
Get an HO transmission. What am I looking for? I would like to keep the four-speed EAOD setup.
Upgrade the oil pump. Completely blind on this one.
Upgrade the stall converter. Whatever that is.
Upgrade the radiator. If so, what should I look for?
I've also heard some buzz about rear gears. Buncha numbers and decimals. What's that all about?

I've already replaced the fuel pump with a much better one and that alone gave it some fangs, so I don't think I'll have to worry about that. The gauges are fine as well, since I don't plan on driving like a moron and I just had it replaced this year.



Now, I want to give it a stronger heart, but I don't want to take away its soul. I would like to keep whatever parts I can, but I'll improve anything that can be. Believe it or not, all the performance stuff I want to do to it is purely for practicality. The speed is just a nice side-effect.

My budget is very limited and this is all very long-term stuff, but if I have a list I can make plans. I want to keep this thing as long as I possibly can, so I consider all of this an investment. This is what I drive every day, so I want to get the most out of it.

Thank you for your time.

[L1011tristar17]

I am also looking to do the same swap in the next four years (no supercharger though). I've done a bit of research so I might be able to answer some questions.

The HO will be just as reliable as the stock 302 you have right now. It has a lot of the same architecture. A lot of people claim that the HO gets better efficiency because it can "breathe" better. If you don't already have dual exhausts, I would plan on getting them before the swap. A HO swap with a single exhaust set-up would be pointless. The HO swap is among the cheapest you can do since minimal modifications are required and a lot of parts from your Mercury can be reused. You can get a lot of parts from a junkyard or a wrecked parts car, or you could spend more coin and buy new stuff. Mustang 302 parts are plentiful.

Your fuel injection system is already SEFI. All Ford full-size cars after 1986 came that way. You can use the stock AOD although a lot of members who have done the swap will probably recommend a good stall converter or shift kit to help it keep up with the engine. If your transmission is already on its last legs, budget on a replacement as an HO motor might finish it off. Not sure about the oil pump and radiator.

Since your car is already running fine as is, I would start looking for an HO motor anyways, buy it, and spend time inspecting it and replacing gaskets and sensors. Then once the motor in your car finally goes out, you already have a fresh motor to drop in.

Also, don't forget an intake spacer and new engine computer. The HO won't run right with a Lopo computer.

[sly]

easiest is to just swap the whole motor in (build it outside the car and swap in). Depending on how much boost you want to eventually run, will decide what level of pistons you want to use. The HO pistons will do well up to about 10 or 12 pounds IIRC which is great for what most people want. If you use an complete HO engine, you will only need the bored out EGR spacer to allow for the cables to be mounted properly and the properly setup throttle body (linkage arm is the lever that the cables connect to). If you use an Explorer motor... you'll have to modify the fuel rail setup as well since the fuel pressure regulator ends up under the egr spacer causing interference.

as for the ignition, you already have SEFI... you just have the speed density version instead of the mass air flow version. You will need to modify the wire harness to the engine computer and 3 wires and possibly move 1. I'd have to go back and look at the pinout charts to see which again.

The transmission isn't as big a deal. You can use the one you have now and it'll work fine, just shifting early at WOT. You would need the shift governor replaced is all. A higher stall (like 2400) torque converter will really help the butt dyno feel and help with moving off the line.

The oil pump will come with the HO engine if you use a complete engine. Otherwise, just get one for a early 90s mustang.

The radiator will work fine, but upgrading it to a two core would be helpful.

+1 stock fuel pump in good working order will be fine

You best option would be to fine a low mileage HO engine from anything other than a mustang and use that as a base to build the swap.

[ootdega]

I am also looking to do the same swap in the next four years (no supercharger though). I've done a bit of research so I might be able to answer some questions.

The HO will be just as reliable as the stock 302 you have right now. It has a lot of the same architecture. A lot of people claim that the HO gets better efficiency because it can "breathe" better. If you don't already have dual exhausts, I would plan on getting them before the swap. A HO swap with a single exhaust set-up would be pointless. The HO swap is among the cheapest you can do since minimal modifications are required and a lot of parts from your Mercury can be reused. You can get a lot of parts from a junkyard or a wrecked parts car, or you could spend more coin and buy new stuff. Mustang 302 parts are plentiful.

Your fuel injection system is already SEFI. All Ford full-size cars after 1986 came that way. You can use the stock AOD although a lot of members who have done the swap will probably recommend a good stall converter or shift kit to help it keep up with the engine. If your transmission is already on its last legs, budget on a replacement as an HO motor might finish it off. Not sure about the oil pump and radiator.

Since your car is already running fine as is, I would start looking for an HO motor anyways, buy it, and spend time inspecting it and replacing gaskets and sensors. Then once the motor in your car finally goes out, you already have a fresh motor to drop in.

Also, don't forget an intake spacer and new engine computer. The HO won't run right with a Lopo computer.

I dunno, I really don't see this thing going out anytime soon, if ever. It'd probably take extreme effort and sabotage on my part to do it in. If it'll improve efficiency then the sooner I do it the cheaper it'll be.

But you cleared up a lot of things. I forgot about the computer and I'm glad I won't have to bother with the injection timing. The transmission seems to be happy as can be, so I'll just have to find out about stall converters.

I was told that the thing had essentially been sitting in a garage for about 10 years before the person bought it to sell, so that would explain why its drivetrain is gentle as a kitten but I've had to replace a lot of auxiliary parts.

[ootdega]

easiest is to just swap the whole motor in (build it outside the car and swap in). Depending on how much boost you want to eventually run, will decide what level of pistons you want to use. The HO pistons will do well up to about 10 or 12 pounds IIRC which is great for what most people want. If you use an complete HO engine, you will only need the bored out EGR spacer to allow for the cables to be mounted properly and the properly setup throttle body (linkage arm is the lever that the cables connect to). If you use an Explorer motor... you'll have to modify the fuel rail setup as well since the fuel pressure regulator ends up under the egr spacer causing interference.

as for the ignition, you already have SEFI... you just have the speed density version instead of the mass air flow version. You will need to modify the wire harness to the engine computer and 3 wires and possibly move 1. I'd have to go back and look at the pinout charts to see which again.

The transmission isn't as big a deal. You can use the one you have now and it'll work fine, just shifting early at WOT. You would need the shift governor replaced is all. A higher stall (like 2400) torque converter will really help the butt dyno feel and help with moving off the line.

The oil pump will come with the HO engine if you use a complete engine. Otherwise, just get one for a early 90s mustang.

The radiator will work fine, but upgrading it to a two core would be helpful.

+1 stock fuel pump in good working order will be fine

You best option would be to fine a low mileage HO engine from anything other than a mustang and use that as a base to build the swap.

I thought I read about the wiring somewhere. That's definitely not something I would be able to do myself.

Unfortunately an entire engine block wouldn't be an option. I don't have the resources or space to store one. This engine is in great condition, so I think it'd be the option with the least guesswork either way.

I'll remember to avoid getting any parts off a Mustang that recieve a lot of friction though. That's good advice.

[sxcpotatoes]

Trust me, you want the entire HO motor, block and all. Get it from a Lincoln Mark VII (7) if you're worried about someone having abused it, there are plenty of complete motors around here for $4-600 at junkyards with warranty, they bolt right in after you flip the intake (and replace the timing chain/gears and water pump just to freshen everything up).

You get the better pistons and everything that will be more capable of handling boost. New computer (tho I haven't done one personally, is essentially switching pins on the plug into the unit up by the brake pedal.

You will need a snap/screw oil cap as there won't be free space to rotate the regular oil cap off with the flipped intake.

[sly]

you can use a D9S engine computer and Mark VII engine from 89-91 Mark VII and it would be plug and play direct swap. no wiring required. This would entail an engine with E7 heads and HO upper intake and cam. The fewer mods the better for that setup and it should work right out of the box.

[zoomie]

can also use the mustang DA-1, little easier for tuning and is speed density, some people like mass air, but im a speed density guy.

[87gtVIC]

You will need a snap/screw oil cap as there won't be free space to rotate the regular oil cap off with the flipped intake.

This is simply because of the valve covers that HO engines came with. You can easily install your stock panther valve covers in place of the aluminum covers and your oil fill cap will clear just fine like stock.

[gadget73]

Thing is, if you don't swap in a complete engine, you need to remove the existing one to completely tear it down in order to replace the pistons with forged ones. This is not needed without a supercharger, but I would not supercharge anything with those stock pistons. I wouldn't stab new pistons into a block without it going to the machine shop for measurement and honing or boring as appropriate, and new bearings. The amount of downtime this involves makes rebuilding the existing engine only make sense if you can afford to be without the car for about a month, just to allow for shop time and such.

Im not so sure I'd go speed density with boost either. Its not designed to deal with positive manifold pressure. It has been done, but it involves what amounts to a hack to make it all behave. Its called a Fuel Management Unit, and involves a bunch of check valves to make sure the MAP never sees pressure, and it essentially over-rides the stock regulator to crank the fuel pressure when in boost mode. Basically, most people quit using that stuff when mass air became available. Without boost, SD works very well and requires basically zero work to make it all play. Swap the computer and you're good.

[ootdega]

Thing is, if you don't swap in a complete engine, you need to remove the existing one to completely tear it down in order to replace the pistons with forged ones. This is not needed without a supercharger, but I would not supercharge anything with those stock pistons. I wouldn't stab new pistons into a block without it going to the machine shop for measurement and honing or boring as appropriate, and new bearings. The amount of downtime this involves makes rebuilding the existing engine only make sense if you can afford to be without the car for about a month, just to allow for shop time and such.

Im not so sure I'd go speed density with boost either. Its not designed to deal with positive manifold pressure. It has been done, but it involves what amounts to a hack to make it all behave. Its called a Fuel Management Unit, and involves a bunch of check valves to make sure the MAP never sees pressure, and it essentially over-rides the stock regulator to crank the fuel pressure when in boost mode. Basically, most people quit using that stuff when mass air became available. Without boost, SD works very well and requires basically zero work to make it all play. Swap the computer and you're good.

I don't have any method of transporting or storing an entire engine. This car's all I've got. The suspension could handle 500 pounds with a little extra air, but the trunk most certainly cannot. One of these days I'll reinforce the trunk, but it is not this day.

Plus, I know this engine runs flawlessly. I wouldn't have that with a junkyard block. I'd rather be a month without it than have to be worried that the engine is going to work at all. Along with that, I can buy one part at a time and have an easier time doing so. Once I have everything I need, I can make plans to be without it until it's finished. Shop time will be....expensive, but I have to make do with what I've got. If all goes as planned, these things will end up paying for themselves.

Mass air sounds perfectly fine. The fewer things that can break, the better. I don't want super speed, I just want better efficiency and power.

I need the least possible number of variables. As long as I know what I need I can go from there.

[sly]

in that case... don't worry about modding it until you can do it all at once (and maybe pay someone else to do it). Start out with the dual exhaust, upgrade the rear gears to at least 3.27 or 3.55 (this will increase city mileage if you keep your foot out of it and make highway driving much more enjoyable and probably net 1mpg on that end too). You can do those mods without touching the engine and they will still be helpful when you do the HO conversion.

[L1011tristar17]

For transporting the engine, you could look at renting a small truck. U-Haul comes to mind as well as hardware stores (Lowes, Home Depot, etc.) I also read that some dealerships loan out their loaner trucks for a fee. As far as engine storage goes, storing the miscellaneous parts will probably take up more room than the assembled engine on a stand would.

[L1011tristar17]

in that case... don't worry about modding it until you can do it all at once (and maybe pay someone else to do it). Start out with the dual exhaust, upgrade the rear gears to at least 3.27 or 3.55 (this will increase city mileage if you keep your foot out of it and make highway driving much more enjoyable and probably net 1mpg on that end too). You can do those mods without touching the engine and they will still be helpful when you do the HO conversion.

+1 exactly. Start small first. Swapping in an aero axle will give you rear disc brakes and better gearing. When it comes time to replace the front suspension, do the big brake swap. 3G alternator conversion is nice too and a very easy project.

[ootdega]

in that case... don't worry about modding it until you can do it all at once (and maybe pay someone else to do it). Start out with the dual exhaust, upgrade the rear gears to at least 3.27 or 3.55 (this will increase city mileage if you keep your foot out of it and make highway driving much more enjoyable and probably net 1mpg on that end too). You can do those mods without touching the engine and they will still be helpful when you do the HO conversion.

Something like this?

http://www.ebay.com/itm/Ford-8-8-inch-rear-end-gear-3-55-/291016583034?pt=Motors_Car_Truck_Parts_Accessories&hash=item43c1f0a77a&vxp=mtr

For transporting the engine, you could look at renting a small truck. U-Haul comes to mind as well as hardware stores (Lowes, Home Depot, etc.) I also read that some dealerships loan out their loaner trucks for a fee. As far as engine storage goes, storing the miscellaneous parts will probably take up more room than the assembled engine on a stand would.

Possibly, but I wouldn't have to put it all in one place and it wouldn't be 500 pounds.

+1 exactly. Start small first. Swapping in an aero axle will give you rear disc brakes and better gearing. When it comes time to replace the front suspension, do the big brake swap. 3G alternator conversion is nice too and a very easy project.

I've already replaced the entirety of the brakes when they pretty much died a couple months after I got it. I don't know what they replaced them with, I wasn't really paying attention, but I'll keep the disc upgrade in mind. I've also had the alternator replaced and I don't know what they replaced that with either. They did have to later modify the cable harness to get it to clamp properly and it works a lot better than the last one, so it might be a 3G. No idea how to tell though. I really didn't start paying attention to all these things until I started planning for the long-term.