Downpipe

In the past few days I finished the welds on the downpipe so that everything matches up quite nicely. The welds aren't pretty but I think they will be strong enough. I erred on the side of strength versus appearance.

Tough to tell from the picture, but the downpipe is now orientated pretty much straight down from the driver side exhaust outlet. In my previous posts I explained how the stock ABA downpipe was having issues being too far towards the passenger side, so I'm optimistic this will solve the problem. I'm still a bit nervous the whole thing will have too much depth to fit in front of the firewall.

I also cut mostly new gaskets myself with the exception of the actual turbo onto the manifold. I decided to go gasket-less on this. Hopefully it doesn't prove to be a mistake, but a lot of my research showed that people that did use gaskets kept blowing them. I'd rather have a small leak not using a gasket than a big hole where a blown gasket used to be.

I plan to pull the oil pan off the 16v motor to tap the oil return into - the oil pans should be the same size and thus easily interchangeable. For the coolant lines, I'm thinking about using the heater core coolant lines. I could simply tap into the line going into or out of of the heater core. The only problem is the heater core lines are much bigger than the nipples currently on the turbo. The turbo nipples are currently reducing to the line, so I might be able to find alternative ones that expand to the proper size for the heater core.

Turbo and manifold - first look

I eventually gave in and made a deal with the guy on the Vortex for the BBM throttle body adapter. While I still feel it is quite expensive (the most expensive part on the motor so far) I believe my amateur attempts at welding something that sophisticated would have failed, or at least taken a long time to complete. After thinking about it for a while I decided I'd rather not have the entire project sitting idle while I debated whether I could make a CNC machined part out of a Dremel, scrap metal and amateur welding skills. This is something what it should look like:

Since I am now pretty comfortable the motor runs as it should in naturally aspirated form, its time to get going on the turbo. The first step was to piece everything together and get a rough idea of how it will fit. When I was choosing the manifold, I wanted something that kept everything at right angles since I thought it would keep things simple, and the downpipe I acquired already had a right angle on the wastegate from the turbo exhaust flange, so I thought it might get lucky and it could actually fit. It may turn out that this was a bad mistake. Since the turbo is sticking straight out from the cylinder head, it requires more room than it may have require more room than if I bought a manifold with an angled flange. My rough measurements suggest it may just squeeze in place - but if I could do it over I would buy an angled flange.

I then rebuilt the turbo charger itself to realign the charge pipe. Its original position would have pointed straight back into the exhaust manifold, so I realigned it such that the charge pipe points straight up parallel to the cylinder head. This configuration should allow for easy intake and charged piping.

Piecing everything together I began to think about how I would run the wastegate's boost line and the coolant and oil lines.

For the boost line, there is already a nipple on the charged side of the compressor that I could simply run to the waste gate, however, this would leave me with no control over boost aside from the pre-set spring included in the wastegate, which I am not sure what its set at. This leaves me a choice of running it as described as a temporary solution to get things running, or perhaps warrants the search for a boost controller on the forums somewhere. Ideally I'd find an inexpensive boost controller that I could run the lines for before everything gets installed to avoid any difficulties working in the tight spaces later.

For the oil lines, I can run the oil intake straight from the oil filter housing. There are two spare bolts on the filter housing I could screw a threaded adapter into - unfortunately I stripped both the bolts out trying to remove them, which means I'm now likely committed to a thread removal tool - I'll see if I can find one to borrow. The oil return line will need to be tapped into the oil pan.

Last is coolant lines, for which I have no idea how I am going to run. One option would be to tap the side of the cylinder head. I'd rather not take this approach since an error would be catastrophic to the whole project. Off the top of my head - I'm thinking an adapter on the flanges - both in and out, is the best solution for this.

It Runs!

Happy to say I finally got it started! After the distributor modification, I couldn't get it to start for a few tries. The first thing I did was test the spark plugs, and realized that they weren't working. I should have guessed this would be a problem since I was using the original plugs from the 16v head as I received them, and who knows how old or what kind of shape they were in. I replaced the plugs with the ones from the ABA head, since I knew those were working properly, tested again and was able to observe a nice blue spark when the engine cranked.

Replacing the plugs wasn't enough to fix the problem - after a bit more tinkering I realized that the distributor wasn't firing cylinder 1 at TDC (which - as I understand, is proper timing). I reordered the plug wires from the distributor and it fired up!

Getting it in a state to run required quite a bit of annoying tinkering -

- the original fuel lines didn't fit the fuel rail. I bought the proper sized fuel lines but then also had to deal with reducing down to the connecting points which lead to the fuel tank. The guy at Parts Source helped me out with a variety of brass fitting to get me to the required reduction. After installing these fittings, however, fuel began to leak from the thread on the fittings - I had to buy gasoline thread tape at the Home Depot before the problem was finally fixed several hours later.

- the downpipe for the 16v didn't quite match up to Catalytic converter. Again, this was a huge headache for multiple reasons. First of all, I had to crawl under the car (still with walking boot on foot due to ankle injury) which I absolutely hate doing. Then I had to try and pull apart the exhaust joints as best I could to give me some wiggle room which required me to heat them with a blow torch for a few minutes and smash them with a hammer until they finally gave in. Then I was able to wiggle the CC reasonably close to the downpipe but realized that the real problem was in the fact the downpipe was slightly closer to the passenger side then desired. This caused the O2 sensor on the catalytic converter to hit the heat shield. My ghetto solution to this was to bend the plug on the O2 sensor away from the heat shield as carefully as possible to avoid damage to the wiring which allowed additional clearance to get 2 of 3 bolts on the CC up to the downpipe. I left it at that, since as I will discuss later, the whole thing is going to come apart again anyway.

- the MAF sensor was previously on the passenger side - as you can see in the picture - I extended the wiring over to the driver side as a temporary solution, since again, I intend to pull everything apart again eventually.

- The PCV valve is rigged up from a generic PCV valve purchased at parts source connected to a hose attached to the lower intake manifold. I did some searching and apparently this hose is intended to act as a breather for the crankcase. This solution should last permanently.

- The Fuel pressure regulator vacuum line is currently running to the cold start mechanism on the 16v head, which I will eventually block off.

-The majority of the other vacuum lines are tee'd off the brake booster line at the back of the manifold which again should be a permanent solution.

- The intake is the most annoying problem due to the odd shape of the 16v intake. To get it running, I simply stretched the ABA intake over the 16v TB. I ran the ISV plumbing into its original location on the ABA intake manifold, and used a rag or ducktape to block off all remaining openings. Stretching the intake over the 16v was a real test of patience. This solution was enough to get it started and idling properly, but ass discussed earlier, the 16v throttle body does not have the required sensor for the ABA ECU. When testing the throttle, however, I had no throttle response (which at the time I assumed was due to not having a throttle position sensor). To test this thory, I tried connecting the TPS to the original ABA throttle body on the side, and manually opening both the 16v and ABA throttle bodies while the engine was running to achieve throttle response. While this worked moderately, it was still pretty sluggish, and at the time, I figured my method of testing this was simply too crude to work. I then decided I would need to find a way to rig the ABA throttle body to the 16v intake manifold or find a way to get a 16v throttle body with appropriate sensors.

- Apparently a 16v Passat TB with AUTO transmission would work sensor wise. Unfortunately I'm not allowed into junk yards because of my boot, and I wasn't able to find a Passat with automatic transmission anyway, and apparently there are hood clearance issues with this solution as well. I decided instead to rig the ABA TB to the 16v manifold. In theory this is simple, but the 16v manifold has an odd shaped opening making difficult, if not impossible to get any type of coupling attached to the manifold. Additionally, the intake requires a sharp 90 turn to clear the coolant expansion reservoir further complicating the problem. My solution required many hours of tinkering with various pieces of scrap tubing, couplers, etc, as well as a piece of flanged exhaust piping I was able to connect to the ABA throttle body, and some expansion pieces. I finally rigged something up, again, just for the purposes of trying to get the engine revving properly in response to the throttle, which involved my odd contraption of piping rigged up to the ABA throttle body, attached to the ABA manifold, which I again stretched over the 16v intake manifold flange.

- After doing all this, I still had no throttle response - even with the ABA throttle body and a functioning TPS. That said, the motor still idled reasonably strong. Because the throttle was now downstream of the ABA intake, the motor vacuum sucks up the rubber ABA intake - which was funny to see. Frustrated, I began to google randomly my issue, and the MAF came across as a possible solution. To test I simply pulled the MAF sensor, and it revved up beautifully! I must add that it sounds awesome, and much stronger than the old 8v head. So I was happy that I was able to diagnose the revving problem, though a little bit sad it had to be the MAF, which is ridiculously expense. I'm optimistic that there is a problem with my MAF rewiring, or perhaps that the MAF might just be dirty, and that there is nothing wrong with the sensor itself.

So that was basically the path I took to get the motor performing properly. Obviously, there is quite a bit of frankenstein, and at times, sloppy solutions to get things running in the garage. The reason for this is that I purchased a variety of turbo parts from members of the VWVortex community and ebay. These included a turbnetics T3/T4 turbo, turbonetics wastegate, air-air IC and various piping, blitz BOV, and various other components. I also sourced a downpipe, and bought a manifold off of EBay. Everyone has an opinion on the ebay parts - but I have to say, this manifold looks to be pretty well constructed, and of unexpectedly good quality for $50. Now that the motor is running properly, the next steps will be to weld up the downpipe so its fits the manifold, wastegate, and turbo flange properly. Once I'm comfortable with that, I'll pull the head again to install the turbo. I'll also need to pull the oil pan to tap an oil return line.

I'll still need to find a permanent solution to my intake problems. BBM sells an adapter for using the ABA throttle body on 16v motors, however its ridiculously expensive. I asked around the VWvortex for anyone looking to sell this part, and found one guy with one he doesn't need, but he still wants $150 for it, which  I think is ridiculous for a simple adapter. I doubt he'll sell the part to anyone else any time soon, so I'll sit on that for a while.

Ultimately, I think I might try to weld up and fabricate my own adapter - materials wise it would be considerably cheaper than $150. Also, I'll likely need to make weld modifications to the down-pipe, and will have lots of inter-cooler piping that could use some welds as well, as well as body work down the road.

As winter closes in - that's pretty much where I'm at.