V-6 Headers

The end as finally come to a project I started 5 years ago. As some of you know I had imported a set of header for a (KF) 2.0L Astina from a South African manufacture, after it was realized that none of the headers available for the MX-6/ 626/ Probe GT could be easily adapted to physically fit under the body of a MX-3. The major obstacle is that the is more that 8" of additional room between the firewall and engine block in a (GE) chassis car. This also means that it is almost impossible to remove the OEM exhaust manifold and install the rear header while the engine is still in the car. Earlier in the winter I lost the timing belt in my engine due to the hydraulic belt tensioner failing. Since I had planned to install a fresher engine in the car. I decided to swap the engine out at this time rather than replace the just timing belt. Unfortunately I didn't have the facilities to do the work myself so I farmed to work out to Advanced EFI a shop that had the reputation to be the best in the area for import swaps which turned out to be a bad decision as the work progressed. They operate more like a chop shop, than a garage, meaning they knew how to get an engine out of a car fast but had a lot of problems putting one back in. So a simple plug and play engine swap that was started in March stretched out until mid July before I took the car back then had to spend another 3 weeks at night and weekend working on the car to undo the many safety hazzards that I found while trying to figure out why certain things didn't work. 

  Getting back to fabricating the headers. Since the engine was out, this would be a good time to installed the headers and have all the jigsaw puzzle of pieces of pipe welded together. The Steve and his guys at Advance EFI in there infinite wisdom decided to throw out all the sections of pipe I had bend and cut to make the pipes equal length from both banks of cylinders. I only found this out when I picked up the car and found that they decided to take a short cut and ran the secondary pipe directly into the collector. Modifying the header isn't as simple as just cutting out the extra lenght of tubing and welding it back together. They had no clue what they were doing. For the header to work at it's full potential the collector pipes should be equal length. Cutting a section out of both pipes the one coming of the rear bank of cylinders would be very short where the one off the front bank would be extra long. Needless to say the exhaust pulse frequency cause a back flow of gas up the opposite side. The engine had no power and felt like there was a potato wedged in the tip of the muffler and the car sounded like a sheep having this baaaa-ahahahah exhast sound when accellerating. Have made several calculation and CAD drawing prior to having the headers installed I knew exactly what the problem was as soon as I fired up the engine.

Fortunately my friend Rico has a portable MIG. I had to order several sections of mandrel bent J-pipes and cut, piece together and weld a them together to remanufacture the lower portion of the header myself. After 7 hours of welding and grinding I was ready to bolt back in my new equal length headers. While I was at it I had some additional tubing swagged welded in an A.R.bell into the primary pipes to keep all the gases flowing the right direction. I have driven other cars with the KL-ZE engine but now that my new KL-ZE can breath correctly I freaked out a few people including myself when I found that I could be rolling at 30-40 kph in 1st gear let off the throttle then drop the hammer hard that I could break both TOYO T1-S tires loose at the same time. (For some reason both side of my differential has become locked together a while back). As my calculation predicted the engine would become a bit of a dog of the line up to about 6000rpm then take off like a rocket to redline. Further wrapping the header tubing with Thermal wrap seems to enhance power even more by retaining heat in the pipes keeping the gas velocities high and keeping the heat out of the engine compartment.

What made all the work worth while was I was in the merge lane to get onto the highway while I was making some of my first test runs. I started to accelerate hard and it was only then I noticed a Integra R beside me. I assume he was trying to cut infront of me to get on the highway at the time. There was still a lot of room and distance to the exit and I moved over a little anyway to make sure there was enough room for two car in case he didn't decide to back off and fall in behind me. At about the same time I hit about 6000rpm and he went from beside me to my blind spot. Watching him in my mirrors I started to realize our distance was remaining constant but after a shift but I would keep opening up the gap as soon as I approched 6000rpm. What really made me laugh was when was when I was out for coffee with friends and a kid at the next table was say he was with his friend in his Integra R and some guy in a blue "Turbo" MX-3 with a big wing kept pulling away from them. One of the guys I was sitting with turned around and said that there is no turbo or NOS in that car. When the other group asked how he knew. My friend pointed at me and said that's my car. At which point I had to show them that the boost gauge on the gauge pod was not connected to anything.