Got Boost? Part 1

Overview
It's been a long time since I updated the site. In the last few months, I've been really busy with the family. My son is walking now and he's getting into everything! He's a lot of fun, but he's kept us plenty busy.

Boost is still a ways out, but I thought I'd start off by installing my ef-1 Z21 camshafts. They are a pretty substantial upgrade over the stock Integra camshafts. They feature a bit more duration and a bit more lift. They are technically "all motor" cams, but ef-1 (Rocket is the head man...see their site) says they'll work great with boost as well. Before I got started with the cam install, I had to swap in a new exhaust manifold and downpipe. An unfortunate accident with the impact wrench claimed the life of my previous manifold (I had previously used the D16A6 manifold and downpipe).

Here is a look at the D16A1 exhaust manifold. This is the factory manifold for this engine. I did not use it the first time around because the downpipe for it was not easily useable.



This is all that was useable of the downpipe. The junkyard had used a giant pair of snippers to cut the exhaust apart. Everything behind this point was crushed.



Here's the test-fit of the new downpipe. I saved the rear flange from the D16A6 setup and had to weld it on at a slight angle to things to line up correctly.



After tack-welding everything while it was on the car, I finished it on the bench.



Here is the finished product on the car. I love my gas welder. For jobs like this, it is an awesome tool.



Fast forward to the cam install. Here is a look at the old cams on their way out of the engine.



Here's the ef-1 intake cam (bottom) next to the stock Integra intake cam (top). The ef-1 cam showed about .3mm more lift, but I'm not entirely sure that my method of measurement was very accurate.



It's hard to really see a difference in the profiles, but here is a picture anyway. The stock intake cam is on the left and the ef-1 intake cam is on the right.



Here's a close-up of the exhaust cam lobes. You can see that the ef-1's base circle is a lot smaller. They had to remove a lot of material off of the stock cam lobes to achieve the lift and duration that they were after. The ef-1 cams are based on ZC cores. The D16A1 cams will not work. They are too small.



This pain in the butt problem reared it's head again. When the cams are locked at TDC (via a 5mm dowel pin through the cam plate and into the camshaft), the cam gears do not line up perfectly. So, do you set the cams at TDC using the dowels or do you use the gears?



As you can see, the Integra camshafts do not have this problem. When the cams are locked at TDC, the gears do line up perfectly. I've always set the cams at TDC by using the gears, so that is what I did. The camshafts felt like they made less power than the stock ones! I suspected that they weren't timed correctly, so I tore things apart again.



I started to wonder if I should have timed the cams by locking them at TDC via the 5mm dowels. After talking to a couple of people that had been down this road (Thanks to Paul D and The Acid Beaver!) and doing this little experiment, I was confident that I had it figured out. This picture shows that when the cams are locked at TDC via the dowels, the slots on the back of the cams (for both the ZC and Integra cams) were in the same place.



Here are the re-marked gears...ahhh, what a mess. The original markings from AEM for SOHC Civics. The new marks that I had previously scribed made the gears work for the 86-89 Integra cams. The newest marks (I did them with an orange paint marker) make the gears work for the JDM ZC cams. Notice that the intake cam marks are the same for the Integra and ZC. However, the exhaust cam is off by 1 tooth. So, my initial install had the exhaust cam off by 1 tooth.



So how do the cams run? They make power!! I haven't played too much with the cam gear settings yet, but I can already tell you that these cams are gonna be fun!




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