Firstly….Happy Easter to all! I hope you get to spend some quality time with your family – remember how precious they are.
It has been a busy Easter break for us, so I have slotted in a couple of hours wherever I could to make some more progress. Now that the front and intermediate pipework is pretty well done, I started on the balance pipe. The balance pipe links both sides of the dual exhaust system, improving efficiency as well as reducing noise levels and giving it deeper, smoother note.
The balance pipe needs to join both downpipes approximately the same distance along the pipe from the manifold. The first thing I did was mark every 50mm along each pipe along the centreline measuring back from the front flange.
I re-fitted the pipes to the car, along with the muffler and intermediate pipes so I could start to measure the crossover pipe position and dimensions. Fitting a balance pipe to a vehicle with an X frame chassis is a bit of a challenge as there is nowhere for the pipe to cross where it doesn’t hang down below the chassis rails. After playing around for a few minutes, 380mm was the distance which looked the best.
I then made the two pieces of pipe to join into the main pipe. I decided to use 2″ pipe rather than 2 1/4″ for the balance pipe as it will be a little bit easier to work with.
I tacked up the first couples of pieces to give an idea of what the pipe would look like.
I then removed the front pipes so I could cut the holes for the balance pipe before I could finalize the balance pipe. I started by drilling a series of holes, and then proceeded to snip the small pieces of metal left using some side cutters. I used a carbide burr in an electric die grinder to then round out the hole.
Once the holes were complete I re-fitted the front pipes to the car and finished off the balance pipe. This was tricky as I needed to make sure the pipe does not introduce and stress to the system.
I cut the finished balance pipe where I wanted to split it (for removal), an then joined it again using a band clamp. This enabled me to tack the assembled balance pipe to the front pipes on the car, and then remove them for full welding.
Once I had welded the pipes and cleaned them up I decided to I give them a first coat of paint. Preparation involved sanding the pipework with 80 grit paper followed by a wipe with acetone. The paint I am using is made by KBS Coatings, and is called XTC Xtreme Temp Coating – I chose Cast Iron Grey rather than Black. The coating needs to dry for 8 hours before I can give it a second coat, and then another 8 hours before you can heat it up.
You can see below what the pipes will look like with the balance pipe installed. The balance pipe crosses over just in front of the transmission crossmember (under the bell housing).
Tomorrow I hope to coat the rest of the pipework in preparation for final fitting.