D M R H - (MY COSMO)

. . . My personal Cosmo . . .

JAN-05

The Cosmo instruments are well laid out for the conservative 90's driver but by todays standards, you cant have a car like this & not know the boost levels your running. Personally, my thoughts are the dash design doesn't lend itself well to additional gauges mounted on it with the exception of a pod mounted steering column unit that blends in reasonably well. The other choice was a little more flamboyant & expensive but the end results are really worth it.

A few years back I wired a digital gauge into a Cosmo & recalled the brand when it came time doing my own. The Dakota Digital range of gauges was sourced direct from the USA it must be said that they have advanced a lot since 1998 when I had first seen them. The idea here is to give the digital boost gauge that factory standard look so as not to ruin the flowing design of the dash area. Made in the USA, meant a return to 19th century measurement of PSI but that is a minor issue & a scale my grand parents can educate me on. So the first thing to do is the removal of the top dash section & finding a place to mount your gauge.

Drilling a hole into the plastic dash frame was done with a 40mm hole saw. Apologies here as I have no "drilling-the-hole" shot of my boost gauge job. In the above picture, another Cosmo owner wanted his boost gauge on the right side of the instrument cluster & I wanted mine on the passenger side to add to the active displays on that side. It’s just a matter of choice. Securing into place was done with some Silastic & note how the Perspex cover has been removed, as the Cosmo Perspex will supplement that.

Mazda painted a matt-black colour onto the inside of the dash perspex. For any of the digital instruments to display the area around them was simply not painted. So for my application the perspex was masked up around the new gauge position & the paint rubbed back with thinners until you could see straight through.

The remote boost sensor locates in a different position requiring a hose from the intake manifold to be plumbed into its internal MAP sensor. You can see here its mounted above the left side "kick panel". Quite simply, it requires power & a single "data" line to go to the gauge. Note how far the kick panel mounting bracket sticks out, there was plenty of space for this module. Running the vacum hose through the firewall meant cutting a channel into the main engine harness rubber-bung that plugs the large hole in the firewall.

Setting of the high-level warning & calibrations is done at the remote module by shorting wires in a certain combination. I have set the high-level to 15-PSI meaning the display will flash quickly if it exceeds that mark. Those in-the-know would know that anything over 1-Bar is asking for trouble on these twin turbo's.

You can see here the end result looks very factory standard & most comments are from people asking if it actually is standard. It blends in reasonably well with the other gauge colours & responds quickly. The only (minor) problem is the inability to watch it when your concentrating on the road ahead when the your right foot is planted. Perhaps a steering column pod gauge would be better after all...... So I am 80% satisfied which is good enough.

Since its installation I have found the boost on the 20B to be quite different to what was expected. The Cosmo pulls like a freight train but the readings tell the real story. The 20B peaks boost at 0.83-Bar on the 1st turbo, then after 3500rpm when the 2nd turbo kicks in, boost drops to 0.52-Bar through to redline. At time of writing, I am unsure of the reasons why & have had little spare time to investigate (the joys of family, work & a 30's lifestyles). My suspicions are wastegate control so thats the first area I will be looking at. Next choice after that will be a Blitz boost controller as their "Dual-stage" unit works the twin turbo's well. A steady 0.9-Bar is the goal.

As well as the boost gauge, I got rid of the 1/2-DIN spacer above the recent stereo install with something any car can't be without these days. Drink holders. Mazda didn't start installing these until after the Cosmo started production & due to added costs, even the series-II failed to get some. Thankfully the Japanese-spec series-I MPV received a 1/2-DIN twin cup holder as an (afterthought??) option & after the Japanese Cosmo guys started installing them it was time to follow suit.

Some minor modification was required to get the unit fitting perfectly but once in there the unit looks like it was a factory item. It opens with no fuss & the only issue is the angle. The Cosmo dash is slightly sloped & the MPV dash must have been straight hence the difference which is only minor & doesn't cause any issue with the practicality of its function. ..........Place mouse over pic to view the screen. Or click for a larger version.