We finally were able to hit it again today. The proper turbo housings came in earlier in the week, and I put those on yesterday.
Before I get started, let me just say that I have a 4r70 transmission in the car, and it is far bigger than a 3650 or 6060, and as such, I expect there to be tighter fitment and may need some alterations to make things fit.
Also, one of my requirements during this process is ensuring I am able to service the transmission (i.e. remove the pan) without having the remove the turbos; I may have to remove the driver-side exhaust pipe to get to the shifter cable and bracket, but that is acceptable.
Today the plan was to get my hot side mounted or at least ready to go, with minimal remaining alterations. I've run into some clearance issues with my 4r70, and needed to do a little "material removal" in a couple places on the transmission housing. After a little grinding and test fitment, we could see where the turbo should sit and be mounted, and tried to fit up the exhaust pipe to the turbo; I have concerns where the two meet regarding clearance for the shifter lever and bolt on the transmission, so wanted to connect it up and get it aligned right. Well, the pipes didn't fit right (angles are off, very obvious), so I couldn't get them connected. But also, It seems that I might need to move the entire assembly forward a little, to give the room needed for the shifter lever, or angle it all a little differently. A small change in the downpipe from the manifold will likely be needed to get things where they will sit and clear everything just fine (or, the flange on the pipe is not correct as it sits and does not properly mate up with the exhaust manifold), and then the exhaust pipe will have to be modified to fit.
Next we tried the passenger side. Well, there's a couple things sticking out that will need to be removed to give the pipe more room, so we didn't get very far in figuring out exactly how close or far off we are. But, I can already tell, there is an issue with the O2 sensor bung and how it does not line up where it needs to be, assuming the turbos will otherwise bolt up where it will need to go. Again though, I need to do a little grinding on the trans to make a little room.
We then moved on to doing the same fitments on Leo's car, starting with the passenger side. After monkeying around with it, and getting things aligned where the exhaust pipe would line up, it was clear that there was an issue with the exhaust manifold flange, in that it will not seal up/sit properly where the turbo should sit; if the turbo is put into a position so that the flange sits right, the inlet of the turbo will be clear the k-member, not by a long shot. But, putting the turbo where it should go, according to the pics, and aligning the exhaust pipe with it, we clearly have an issue at the exhaust manifold connection (bad angle for proper fitment).
OK, so we try the driver side. Zip bam boom, fits right up in there, flange fits great, good and uniform fit. Perfect! Then we put up the exhaust pipe to it; the angle on the end is way off, will not fit, not even close. Then we realize, it's about the same as it was on my car. OK so that pipe end wont work and has to be repaired.
So we then start to think and compare pipes, shapes, ends, angles, etc, and realize that everything may things are different, ever so slightly, but enough to see, and with fitment as critical as it is in many places, things are off enough to make proper fitment impossible. This is where having 2 sets of everything is, once again, really helping up. We laid the exhaust pipes side by side, holding them at the same angles in relation to each other, so that we could compare bends and, more importantly, the angles of the inlet flanges. They are quite different, enough so that one pipe definitely wont fit, and the other one might not fit either (although, one of the passenger pipes seemed to align close on Leo's car, but we can't be sure yet).
We then compared the pipes connecting to the exhaust manifolds. Again, both sides different from each other. We know that the driver-side pipe on Leo's car is right, at least for his car, and comparing it to mine, the flange at the manifold on mine is at a different angle, which we saw when trying to fit it up. For passenger side, Leo's we know is off, and mine is at a different angle so it might be ok, don't know; but also, the O2 bungs are in different positions on that pipe, in the area where fitment is close as it is; the bung it mine may be so far off that it can't be used as-is.
We can understand if something does not fit right not alight perfectly on my car, that was expected to be a possibility going into this project. But there is no excuse for why things don't fit Leo's car perfectly and bolt right in place. THAT is what's really sad here.
No doubt we'll get it straightened out and resolved; things will fit, there is room; but the piping must be precise for everything to fit and bolt up properly, and we're not seeing that in some of the pieces right now.
We don't really know if we're putting things in the right place, but after working with the driver side on Leo's car and seeing how well the downpipe flange and angle matched up to the exhaust manifold, when things fit right (and there's room, which there is in most cars), things fall into place quickly and easily. We are not going to force something at an angle where fitment is not right, or where a massive exhaust leak could occur simply because the flange angle is wrong. These will be installed properly. When done, these will be kick-ass setups, no doubt! But in the meantime, we struggle getting the hot-side into place.
Pics:
- clearancing the bottom lip on driver side of trans housing:
fits better now:
turbine outlet is a little close to the trans, and may interfere with the shifter (of course I could use a shorter pin on the shifter, and may need to):
Examples of driver-side exhaust outlet section-to-turbine-outlet, flange-to-flange connection alignment angle issues. These are on Leo's car, but there were very similar issues on mine; these are more of the "closer-fitting" angles, or where pipes should otherwise run and lay in place:
this one may seem a little extreme, but, that's the way it is; the turbo can be raised up some, but not that much to mate up to the pipe:
closer comparison of the two driver-side exhaust pipes: even these are put together different from each other, just looking at the pieces welded together. But look at the flange faces more than anything; and these are the best/closest to getting them parallel with each other!:
(this first one really shows how different the two ends are
passenger side downpipe from manifolds. The one I'm pointing to is from my car; Leo's is way off on the flared flange. The turbo assemblies and pipes are sitting nearly identical, and the angle of the pic shows how different the flange-end is from each other: you can see the inside of the one I'm pointing to, yet the other one is angled differently. The O2 bungs are located in different positions, too (the one I pointed to may not work at all where it is located). Look at the "ring" on the left one; that is where fitment was reasonable (on Leo's car), and indicates how far off-center that end is from where it needs to be.
that's where we are right now.
