got absolutely shat on by the weather over the weekend, garage had a bit of flooding but I was ready for that from experience so everything was already up off the ground. Poor old triumph took a bit of a bath from a leaky roof but no damage done.
I went on another sikk modz tangent because the CA18DET inlet manifold arrived. Port spacing is unnaturally similar, both Mitsi and Nissan even decided to go with the same PSSP PSSP layout so I get the injector bosses in the correct ports. It's quite a strange design, the primary ports get ALL the fuel, the secondary is air only. The DASH engine opens it's secondary inlet valves around 2500 rpm if I recall, things might get a bit strange for a millisecond there as the injector has to double it's output, and God only knows how the charge will mix. Lucky the injectors are so close to the head that the air won't have much of a head start. In retrospect the factory setup is even worse with the injectors way upstream where Mitsubishi originally lazily wedged them in a hollowed out carburetor back in '82 and called it a day. The DASH engine activates the valves at the rockers a la VTEC, the Nissan deactivation system is a bit more agricultural with a TVIS style butterfly which had already been removed from this manifold. The old butterfly shaft bearing hole might be a good place for a vacuum signal.
The coolant port was never going to work so that got trimmed off and went into the bin. Unfortunately the mount hole positions are a bit shit, there's only about 4 studs along the top of the manifold, and two of them are DIRECTLY under the injector bosses. I thought I had a solution by flipping the manifold upside down but that ended up misaligning the other ones even more. Decided in the end I'll pull those studs and countersink those holes on the flange. That'll allow it to be secure, and prevent it from fouling on the injector bosses. The only real downside is that that means the flange will have to go on first, then the rest of the manifold be assembled up against it, rather than it being a nice complete unit. The injector slots in the top of the port may be a problem too, right now they'd effectively be firing into a wall, I only have the thickness of the 7mm flange to try and relieve that. Might end up making a second flange to double the thickness and give me some more room to play with.
Drilled and tapped the flange to suit, couldn't find my tap handle amongst the mess so did the bugger in the vice. The manifold spacing is extremely close to how it wouldve been on the Nissan engine. I could've just about used the factory upper manifold too. The flange will require a little bit more reshaping and probably some hysol/devcon to help build up the larger CA primary ports to match the smaller mitsi ones. The secondary ports are pretty bloody good and will only need a tickle.
Instead I went with quad throttles for the cool factor, they line up so well, the width is perfect, I could've actually just shaved the eyebrows and gotten away without an adaptor plate, if not for (again) the unfortunate position of the mount lugs, one of the three hanging out in the middle of nowhere, and a second one over an existing, larger threaded hole. Thought about back drilling and tapping the throttle bodies so I could bolt them up however I liked but don't actually want to permanently modify them - as we all know they're the second most overpriced engine component on earth (after the RFB 300zx airflow meter) so if the whole thing comes to naught I'd like to be able to on-sell them
Offered the throttle bodies up, became vaguely aware that it was beginning to look like a bit of a tower of shit tbh. I'll give it a clean up and a paint perhaps. By the time the (outlandishly large) 4AGE plenum goes on it'll be quite a big unit hanging off the side, I wonder if I can brace it a bit better. This is assuming I even use it. The 4AGE inlet I bought didn't come with a TPS but the starion one bolted up perfectly after a minute with a flat file lolol. I believe they work opposite the factory toyota ones but it looks like Tunerstudio has provisions for that.
Next project might be cleaning up the bench