| 99 Headswap |
| I have swapped out the cylinder heads, cams, and intake manifold out of my 1998 Mustang GT and replaced them with that of a 1999 Mustang GT. I have received a lot of email with questions about the headswap. Below is a list of the most frequently asked questions as well as information on how you can follow in my foot steps. |
| Why upgrade 96-98 GT's with 99+ cylinder heads? |
| Because the cylinder heads in the 96-98 cars flow very very poorly. This is a major bottle neck with any other performance addition to a 2v 4.6. Once you have free flowing heads on your motor every other mod you do with benefit you even more and more. Heads should be considered the corner stone of building a motor. Ford upgraded the cylinder heads in 1999+ 2v 4.6l's to flow better than GT40 heads. Bolting on a set of 99+ heads onto a 96-98 motor will add at least 40hp and even more if they are ported. It is almost garaunted to drop your 1/4 mile time by a full second. Some people have even dropped as much as 1.3 seconds from the headswap. |
| What all do I need to swap 99 cylinder heads onto a 96-98 block? |
| In order to swap the heads on you will need not only the heads, but the cams, the intake manifold, gaskets, bolts, and various other parts. I have provided a parts list with everything you need. I had a guy who works at the local ford dealership install everything on my car on the side. 96-98 cars have two temperator sensor connectors on the intake manifold, 99+ cars only have one. You will need a T-fitting to connect these together once you complete the headswap.If you decide to do this on your own you will not need any special tools and from what I've heard it isn't a very hard task, it is just more time consuming and involved than swap heads on an older pushrod motor such as a 302. |
| Are 99 cylinder heads the best heads on the market for the 2v 4.6l? |
| As of right now, the only cylinder heads on the market are the Ford Motorsport Heads AKA SVO Heads. The Ford Motorsport heads flow slightly better than the 99 heads. I say they flow better when comparing out of the box Motorsport heads to out of the box 99 heads and when comparing ported Motorsport heads to ported 99 heads. The downside to the Ford Motorsport heads is they are very expensive ($900 each) and do not include cams like the 99 cylinder heads do. |
| How much did you pay for your 99 heads and where did you get them? |
| For the 99 heads and everything else needed for the installation I paid about $1000. The heads themselves (which includes cams) where $250 each. At the time I bought them they were still cheap. The price is on the rise now since ford has found out so many people are buying them instead of their SVO/Motorsport heads. I bought them from Universal Ford in Baltimore, MD. Their phone number is 410-655-2000 *8 for the parts department. |
| Are you running with the stock computer now that you have the 99 heads on? |
| Yes, I still have the stock computer. My car runs fine and does not have a check engine light or anything of that sort. I am going to have a new tune done on my car to see if I can get some extra horsepower out of it. |
| Where did you get your heads ported at? |
| I got my heads ported at Heads Up performance in North Carolina. They charged me $600 for a "street port" as they called it. Their phone number is 910-738-9449 and address 900 Hardin Rd Lumberton, NC; 28358. They also had a "racing port" for the 99 heads, but that was not recommended for a daily driven car. |
| Are there any negative side effects to the 99 headswap that you have come across? |
| I have been running the car for 15k miles since having the heads installed and the only bad side effect to them is the car tends to overheat when sitting in traffic for too long. This is due to the computer not turning on the fan at a low enough tempurator to satisfy the extra power the engine is making. This will not be a problem for someone who does not sit in heavy traffic, but for those who do you need only to have a new computer burnt that turns the fan on at a lower temp or wire in a manual fan switch to manually turn the fan on when you want it on. |
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