New Project - Mustang

So being the avid Ford enthusiast, I went out and purchased a rough Mustang for a good price, a California emissions 1999 Mustang GT with 160K miles on it.  You could say this was a "barn find" because it was literally found in a barn, but its not in that great of condition.  The previous owners didn't take good care of it, but they were an older couple so the vehicle is completely stock - stock exhaust and not even a cold air intake on it...

Why was it so cheap? Well once the engine warmed up you understood why. A loud ticking knocking noise was evident after about 2 minutes of run time. Now we know why it was stored in the barn for a few years.  After closer inspection it seemed the noise was coming from the front cover area so  I drove it home and figured oh well.

Once I got it into the garage, I tore apart the front end. I'm pretty comfortable with modular timing systems if you didn't notice. Ah yes, an easy find - a bad timing tensioner on the right bank. Since I was there, I decided to order up a set of Comp Cams 262AH. The cheapest I found them was on Amazon, but they come and go as far as availability.  I figured "why not!".  I also ordered all new Ford timing components.

That's when things went kind of south for me.  The cams installed with ease, but I noticed all my timing components were wrong even though I looked them up by VIN. Based on my year, I should of had a Windsor block but mine was a Romeo. I didn't think much about it and just got the stuff that fit the Romeo block. Everything was honky dory for awhile.

A few mods later, a buddy of mine wanted to run my car.  He drives a self turbocharged Honda Civic pushing maybe 5psi of boost. I figured what the heck, Ill run him. We raced from a dig and from a rolling 20 and in both cases the Mustang barely won but that poor old 4.6L gave its all - I now had a rod knock.  I spun a rod bearing.  I get it home, rip the engine out, and tear it down and find something rather bizarre.

The block had been changed. I did have a Romeo block, and based on the casting numbers, it was out of a 1997 F150.  The heads were the original Windsors that came with the car.  That created some unique set of problems and advantages.  Since it was a NPI block with PI heads, it created a compression ratio of around 10.5 to 1.  I should have been running premium, but I wasn't aware. The other issue was that those 262ah grind cams were not to be used with a NPI block.  Every single piston had marks from kissing the intake valves.  Apparently its a wide spread issue with the NPI blocks but doesn't bend the valves because the intake valve actually hits the piston on its way down.  The fix is regrinding stock valves and removing the lip or going with aftermarket valves.

So I decided to take this project in a new direction and install a different engine. Read on to continue...

5.4L Drop In Swap

I'v been back and forth on what I want to do.  I had access to a free 4.6L long block out of a 1995 Thunderbird. That would be a downgrade from what I have before.  Even if I used my PI cylinder heads, I didn't know the condition of the engine and didn't want to end up with the same as what I had before.  I came across a heck of a deal on a complete engine out of a 2009 Mustang with 60K miles. It had a spun rod bearing.  I eventually talked him into taking just $150 for it.

I tore the engine down, it was going to need a crankshaft and a complete bearing set but otherwise the block and cylinder walls were in excellent shape.  I was excited to have an aluminum block 4.6L 3 valve that I was going to throw my 2 valve heads onto.  With my heads, it would put me at a slightly high 11.5 to 1 compression ratio.  I was also concerned if my heads would physically work with the 3 valve block.  I found a buyer for both cylinder head/cam combos at $300, sold the valve covers for $50 BUT then someone offered my something I couldn't refuse.  I ended up selling the WAP 4.6L aluminum block for $400.  I feel like I made out like a bandit here. {loadposition adcontent}

Because of my mass profit, and my parts discount because of my employment at a Ford dealer, I decided to take advantage of an opportunity.  Ford produced a limited run of brand new 5.4L short blocks.  The short blocks come assembled, including new pistons, rods, bearings, caps, oil pump, an oil pan. I scored my engine for under a grand.  With my heads, I would be pushing 11 to 1 compression ratio.  The best part being the additional valve clearance because of the extra .120" piston to deck height over the 4.6L.  Remember, I am running the Comp 262ah. I suppose I should contact them about degreeing the cams for a better center-line.

There are many disadvantages with going for a 5.4 in a Mustang.  A bit a physics lesson awaits.  The 4.6L is pretty square as far as bore x stroke. The 5.4L is basically a stroked 4.6L with the same size bore.  The single biggest concern with a larger stroke engine is piston velocity. The piston has to move faster to cover a longer distance in the same amount of time. Historically, engines with a larger stroke to bore ratio are used in trucks because of the need for more torque and low rpm situations.  An advantage of a bigger stroke is higher burning efficiency and less of a chance for pre-ignition and detonation. Big bore and short stroke are better suited for high RPM situations because of the lower piston velocity and better flow from the valves due to less shrouding. The 4.6L being almost square already have the higher RPM disadvantage here, but the 5.4L only makes it worse.

Aside from those physical disadvantages, intake and exhaust selection is lacking. The truck intakes are all aimed at torque production and are too huge to fit under a Mustang hood easily. As far as 2 valve setups, I will be using a set of adapters to install the 4.6L intake on my 5.4L.  A now defunct company called HPS made an aluminum intake natively for a 5.4L in a Mustang.  For those trying the 4 valve route, MMR makes adapters to installed a new coyote intake on Navigator 4v heads. No one mass produces a set of headers that fit this set up.

Many have been down this road before. Most say its not worth the effort to remove an otherwise good engine to do this swap. Obviously my reasoning is that I do not have a good engine. Comparing truck output specs to the original engine is pointless as is evidenced by comparing a 2004 Mustang 4.6L to a 2004 F150 4.6L. At the same time, those that have done it say its definitely worth it for a street car. The extra torque alone will be extremely noticeable. I'd say keep the gearing down to stock or at least under a 3.73 as the 5.4L doesn't like to rev as much as a the 4.6L. That goes for cam selection as well. What good does a stage 2 or 3 cam do for you if you can't consistently rev it out anyway? I always felt they were too high for a stock internal 4.6L, but they are definitely too high for a 5.4L. You'd kill all that newly found torque.

Lets get to building...

Building Begins

A few things worried me about using 2 valve heads on this brand new 3 valve block. The first of which is simple, the oil pump. A 3 valve oil pump is extremely high output otherwise comparatively speaking. I decided to trade out the new 3 valve pump and install the 4 valve Cobra pump. That pump also has a guard build into it to help prevent slinging the oil up the chain.

Reading on casting spec changes on the 3 valve blocks, they raised the head bolt threads inside of the block so that the thicker 3 valve head could still use the same head bolts. It looks as if they raised the floor of the head bolts as well, but it did clear when torqued with the 2 valve heads on it. Everything else lines up as normal.

Clearly the 5.4L oil pan was not going to fit my New Edge stock K member, but since I had a 3 valve 4.6L oil pan around I'd figure I would give it a go. Not quite sure on the fitment yet, but it is bolted up to the engine on the stand. Based on loose measurements, it looks like it will barely fit. It holds a quart more. The motor mounts are in the same locations. {loadposition adcontent}

Swapping to the 3 valve 4.6L oil pan created an issue of it's own. On the WAP 4.6L blocks, Ford installed a windage tray that bolts to studded mains. 2 valve 4.6L and 3 valve 5.4L have baffles in the pan instead. Even if I purchased studded mains, I do not believe the 4.6L 3 valve tray would fit. I ended up purchasing a GT500 oil pan gasket/windage tray combo. It had to be slightly modified to fit the 3 valve pickup tube, I drilled a few extra holes for drainage since the head oil drain holes don't line up. A little more trimming off the front was needed to get it to sit down. At the time, I wasn't sure the pan would fit the stock K-member but it did without issue. The sway bar is pretty close to the drain plug so changing oil isn't as easy anymore, but the pan does hold an extra quart of oil.

With the heads off, I purchased some reground stock MHS intake valves (previously purchased when planning on the 4.6L build), so I pulled the cylinder heads apart and cleaned them up. I took part in a home remedy port and polish job. I should rephrase that a bit. I cleaned up some casting marks, slightly port matched, lightly polished the intake side, and cleaned up the bowl area. I figured screw it and gave the guides a slight taper. Then I lapped in the new intake and old exhaust valves and replaced the valve seals.

Since the engine has a 8 bolt crankshaft, I ordered a new Exedy Stage 2 clutch as well as a Fidanza Flywheel. A few other misc stuff was ordered as well. Exhaust manifold studs and nuts, head gasket set, that sort of thing.

The Build

Once I had everything prepped and the heads put together, it was time to assemble the engine on the stand. I wanted to buy a set of ARP Head Studs but it wasn't really in my budget for this project.  Instead I bought the 3 Valve Ford Performance Head changing kit. Before you ask, yes it will work in my situation. I put the heads in, put the camshafts in, and then set up the timing chains. Nothing different than the usual. I purchased a 3 valve timing chain set to use with my 2 valve heads and it worked flawlessly like my previous mock ups with the worn out junk 5.4L that I used as a core. After setting the chains, I pre-lubed all the lobes and roller rockers and installed them all.

A hugely important part of this swap is the use of the adapter plates. I originally installed these plates with the supplied gasket on the bottom of the plate mated to the cylinder head. That created a problem later when installing the ford intake gaskets on top of the plates. I ended up removing the paper gaskets and buying another set of Ford intake gaskets. More problems encountered and described later.

When I go to reinstall all of the spark plugs, some serious bad luck happens. One of the spark plugs would not get tight and just ripped the threads right out of the head. Luckily, I knew how to repair blown out plugs on 2 valve engines. A slight delay, but fixed right up. {loadposition adcontent}

A small problem I ran into was that I ordered a 3 valve 5.4L dipstick and tube. The 3 valve is set up differently and the bolt doesn't line up with the hole and the tube doesn't fit well through the exhaust manifolds. I got it to fit OK with some finesse. In hindsight, I should have ordered a 2 valve dipstick tube but I was worried that the tube length would be different effecting measurable amount. I also decided not to mess with EGR so I plugged up the tube coming off the manifold and cut the tube off the EGR valve so that I could temporary still mount the valve to the intake plenum to stop the vacuum leak.

Aside from this, I pushed forward: time to set the engine into the car. It was such a tight fit that I removed the transmission to make my life easier. It still was a bare to get in. There is hardly no room on the sides, no room between the AC lines and brake booster accumulator. I forced it in by tilting the engine and using a pry bar to help guide the motor mount studs into the hole. I had already previously installed a X-pipe and wideband 02 sensor, so I had to make a few adjustments to those but everything went together with a little bit a fight.

The rest of the assembly was a breeze and not different than a regular 4.6L until the alternator. The alternator needed to have a custom bracket made to attach to the intake that sat approximately 4 inchs higher (higher deck height plus intake spacers). Temporary ran the alternator without the custom bracket. When the engine was being filled with coolant, I ran into another problem with air pockets. Just like the last issue, the intake sitting 4 inches higher meant the thermostat sat 4 inches higher - higher than the degas bottle. Even using vacuum assisted fill would not get all the air out of the system. The only way it worked for me was to jack the front of the car as high as possible, take the degas bottle off and sit it as high as possible, the vacuum bleed the system. It worked but it was a bit of a pain. In hindsight, the intake spacers had tapped holes in the coolant passages that I would have installed raised tubes allowing for air bleed. I had to cut a large section of the underhood support that would hit the intake plenum.

I do all my own custom tuning using Quarterhorse and TunerPro. Not many adjustments were needed to start the vehicle. I already had a custom tune built for my slightly bigger injectors (Taurus EV6 21lbers instead of the factory EV1 19lb). I did retard the timing a bit for the higher compression ratio. After driving the 5.4L around a bit, I went ahead and purchased a TrickFlow Intake Plenum, 75mm TB, and cold air intake which added a little more air volume, but I think the PI heads and Ford Racing OEM intake are the major restrictions.

While tuning for WOT, I discovered leaning out at about 4500-up. The redline was set at 5800RPM. Turns out the fuel injectors weren't big enough. I purchased some 24lb Ford Racing injectors and tuned them. Now still a little lean on the top end but much closer. My fuel pressure would drop dramatically in WOT. I replaced it with a GT500 pump and now we are all good.

##The NExt Project" alt="The Next Project" class="system-pagebreak" />The story was short on the 1999 Black 5.4 GT Mustang. I ended up selling it. I wanted the cash to pay for something else so someone made a offer on it and I let it go. The guy brought it back to me a few times to get change the tune. I got my quarterhorse back out of it and gave him a F3 chip as part of the deal. He actually put a supercharger on it, a Saleen M90 4.6L supercharger kit that he got for a good price. I was rather unimpressed. That supercharger was too small for a 5.4L. It gave it some great mid-range power, but it drops off fast after about 4500 rpm. I believe the supercharger is becoming a restriction at that speed, as it can't feed the beast enough air.

He actually paid a professional shop to tune it before he brought it to me. It was in bad shape when it arrived. Only dyno'd 280hp to the wheels. Turns out they had vacuum leaks everywhere on the used kit, the belt routed wrong, and the bypass valve was broken in the open position, the intercooler was bad. Lots of little things. Then this supercharger was put on top of a 11 to 1 compression 5.4L running on premium - I had to pull 10 degrees of timing or more across the board to stop the spark knock. Poor car. I think his next adventure is converting the car to run on E85. He'll need to get bigger injectors, but the extra fuel and octane will allow me to put more timing in and keep cylinder temperatures down a bit.

As far as me, I purchased a new Mustang. Well, new to me. A guy brought by one to the shop and needed engine work, decided to sell it. That car got a Saleen supercharger put on, which was underwhelming. Eventually I put together a low-budget 4.6L 4 Valve DOHC engine similar to the Cobra models with the use of 2001 Cobra Heads, 97 Mark VIII block, and 2004 Mach 1 intake. If you liked this post, you should come over and read about the $300 Mustang Project.