Well z-heads, I was imagining a "wow this is the best money spent no flaws" style write-up but it appears that the 123 Ignition distributor has impressed and disappointed me in equal measure. Am I being harsh? Well, at this price point 123 set the expectation bar rather high. Out of the box you get what you see below. Well packaged and at first glance looks well made. The bracket for L28 is a very nicely machined bit of kit. The installation instructions need more work and while there is a video online, it's a bit amateur and more importantly lacks the necessary installation shots. Here's a link to the instructions http://www.123ignition.nl/files/manuals/123manual_TUNEPLUS.pdf And the low budget installation video: So to install, I took out the plugs and turned engine to the end of the compression cycle on cyl 1 I.e. TDC (don't forget there are two TDCs). Taking the cap off the original dizzy, the arm was pointing directly at the radiator panel. I kept the 280zx base. You install the base plate on the new dizzy taking care to ensure it's the right way up for the dizzy base, otherwise it's near impossible to get an Allen key on it. You don't want it tight at this point. The rubber o-ring had to be moved out of the notches and put right up against the base plate to accommodate the 280zx base which has a reamed out bit exactly for the O-ring. Next up you screw the dizzy on and connect the red and blue power wires but not the black which is the coil negative that gets switched on/off during operation. Our dizzys spin anti-clockwise, so you have to turn the distributor body clockwise until the green LED just comes on. It can be seen through the aluminium ring's holes. This is a nice feature as you can orientate the dizzy to where you want it to be. Would have been useful to have in the instructions that the LED goes on and off several times at different points in the rotation, so you don't have to accept the first "on position". After that, you can tighten the base plate clip with an Allen key and the dizzy is set up. At this point I would recommend noting the position of the rotor against the cap. Also it's worth cranking the engine without the cap on to see the arm moving anti-clockwise. While setting up, it became uncommunicative a few times and it had to be reset by joining the red and blue wires. Note that unlike the original dizzy, the spring clips holding the cap on, are simply not strong enough to hold the cap down while unplugging the HT leads. In fact, I had to bend both a little on the first install to ensure the cap didn't wobble BEFORE I had started putting HT leads on. Beware that on the cap, there is a "1" which I was dumb enough to use as my no.1 HT lead position. Don't bank on it!!!! Before cranking the engine, make sure you see how the rotor aligns with which point on the cap. The marked no.1 position on my install turned out to be no.4. Given the firing order 153624, the timing on cranking was in fact 120 degrees - 10 degrees base retarded. First symptom is a condition known as "car no-starty"! Imagine this: WOT and cranking - the mix gets compressed but not ignited, then as the exhaust valve opens, it gets a spark, ignites and gets pushed into the exhaust as the piston is coming back up. Downside: Goodbye baffles in the "turbo" back box! Upside: Hello Sean's lovely straight through muffler. Four neighbours rushed out of their houses to make sure I was alright - promptly followed by my cross wife telling me off for making too much noise! In fact 3 weeks later the neighbours down the road were still debating who would have set off a shotgun in our road! A bit of trouble shooing later and re-orientation of the leads, she fired up. Checked it over with the timing light to be sure and it was dead on. Upside: I learned that my rev counter is a little optimistic and has a 10% error rate. I love the fact that I can play with the ignition timing without so much as opening the bonnet. And no timing light!! Downside: you become a total geek with HOURS of fun on the dual carriageway, testing, pulling over, adjusting, testing etc. Setting the vac curve requires a bit of driving first to identify how much vac is being generated at different parts of the rev range on light throttle / fast idle. The MAP gauge is quite useful for that but tiny on the screen when driving. I dialled back the factory settings to zero, monitored vac at idle (1000 rpm for my 270 degree cam), monitored Vac at motorway cruising range 2000 - 4000 and I didn't bother with anything above. Then I added 12 degrees total vac advance - 280zx dizzy was adding 25 degrees which scares the life out of me! The car simply would not run as smoothly as before and felt like it was intermittently missing. So bad in fact that stoping after a run up the dual carriageway it kept stalling below 1200rpm and failing to start again. I finally got it going before the battery got too low. Having wasted a tonne of time messing with carbs, putting in new plugs, cleaning all contacts again with no better outcome, I decided to rip it out and put in the trusty old dizzy. That is when I discovered an issue which focussed me on the negative points: The electrode on the Beru branded cap that comes with it had "fallen" out. The spare cap had the same issue but worse as the pointy bit was missing off the electrode altogether so I couldn't even put it back in. At least with the first cap I was able to force the electrode back into the spring. A spare cap costing £30 on a £400+ Dizzy should not have this issue, end of! Replacing the Beru cap and rotor with a Bosch equivalent made a HUGE difference. The oil pump drive shaft mating point is too loose causing slack on the rotor arm. A bit of gasket paper had to be used to take up the slack but why am I having to do this on a £400+ bit of kit? Some may contend that the shafts on older cars may be worn. I would contend that an item designed for classic cars should have catered for this with a simple spring loaded insert which I will be making myself. The 40 year old 280zx dizzy on the same oil pump shaft has not got this issue so I suspect they just got their measurements wrong. I sent feedback to the app developers about the ability to see the curve without being Bluetooth connected to the dizzy and being able to switch between curves for different fuel types or track v road use or simply experimenting. They appear to have actioned that now and I'm sure I wasn't the first to ask. Also it would be massively useful to have some data logging for post drive analysis showing revs, vac, timing, speed. Tuning: I set her up with 10 degrees 500rpm 19 degrees 800 rpm (anti- stall) 17 degrees 1000 RPM 35 degrees 3200 RPM 38 degrees 8000 RPM Here's what the app screen looks like Something else that I thought I may feel on the road but can't tell the difference is adding 4 more degrees on the build up to 8000rpm, one for the RR. Here's a table I stole from another Z car site which may be useful for those thinking of replicating their original dizzy curves ... The Bluetooth connection on the app can't quite keep up with real-time events so the readings are slightly behind the times but we can forgive that. Extra functionality The immobiliser is quite interesting. The car starts but as soon as it hits 300-400 rpm it shuts down. The rev limiter is the best I've experienced. It cuts off 60% of the spark randomly across cyls and is silky smooth. It does confuse the rev counter something silly though - the needle jumps all over the place. There is an engine temp dial but I'm not convinced it's true engine temp or could it be under bonnet temp? With my water temp gauge 2/3rds across it was showing engine temp at 80 degrees. To be checked with my laser temp sensor. Interestingly my flamethrower coil takes 2.5-3amps according to the gauges which is double what I was expecting. In summary: The good: fully programmable curve, lots of functionality to play with such as the immobiliser and rev limiter. The bad: at this price point the build quality on cap springs, the cap itself as well as a less than snug fit to the oil pump drive shaft, lets the side down. Installation instructions need more detail for the "average" user or frankly any mechanic not familiar with THIS dizzy. I will continue to add to / edit this post with experiences as I get used to it.