July 2017

Power Steering "Pukage"

I continue to have fluid puking out of the reservoir.  I haven't added fluid and the dipstick is still in the normal range.  I'm assuming I have a suction leak at the pump that's causing foaming, but I had my wife cycle the wheel vigorously at idle and I'm not seeing much in the way of bubbles coming up through the reservoir.  Possibly the issue exists at higher RPM only.  In any case, I decided to go ahead with the planned MR2 EHPS conversion rather than throw any time and money at the stock system.

This is a costly upgrade, but one of the biggest HP bumps you can get for the $$.  Reports vary, but the stock pump seems to pull 1-2 HP unloaded. During heavy steering, read slaloms & sweepers, it pulls 4-7 HP.  The pump can also be relocated to the right rear of the car where DP cars typically need the weight.  The MR2 pump is on the way and I'll dig into the project right after the Packwood tour next week. Fortunately, the leak rate is low enough that I can clean it up between runs without it spreading down into the suspension and onto the ground.

Crank Case Venting

While researching the EHPS line requirements in the rule book, I came across the catch can requirement.  Not sure how I missed this.

Section B. Inspection Requirements. Subsection 10.
No excessive fuel, oil, water, or brake fluid leaks should be observed. For all Prepared and Modified category vehicles, engine crankcase vents and radiator overflow/breather lines must terminate in containers of at least one quart capacity. These containers cannot be vented into the driver/passenger compartment. Crankcase, oiling system, breather, or catch tank evacuation systems that are in any way connected to the ex- haust system are prohibited. Vent tanks are not required with systems which are completely closed (i.e., have no venting to the atmosphere). 

Up until now, I've had the PCV capped off and a small filter directly on the driver side of the valve cover.  A lot of prepared class Miata's have this exact setup, but reading this leads me to believe it's not legal.  I wouldn't protest anyone over it, but I want to be good to the rules, especially inspection requirements.
I decided to add a catch can. I also decided that not using PCV wasn't such a good idea. The system prevents oil contamination by vacuuming out fuel, combustion, and water vapor from the crank case.  Not having much time before the tour, I had to quickly come up with  a solution.  I ordered a basic catch can from Summit Racing.  The mounting solution was to bolt a homemade aluminum bracket to the existing unused stock air box mounting point.  I hate adding more weight here especially since the EHPS will probably go here as well for the rest of the year and then move to the trunk over the winter.

Needing a quick solution, I had some aluminum left over from making other light weight bracketing. I folded this material into triangular boxes and riveted it up

Not the prettiest, but very rigid and very light.  Mounting was easy enough.  I added some large holes, which turned out ugly as hell, to allow socket access.

I fired up the car and warmed it up with the PCV still capped.  I want to see if there's any effect on AFRs, MAP, and Idle.  Since I'm running open loop MAP it shouldn't have any effect other than the fact that I'm adding some hot gas to the intake downstream if the IAT sensor.  After reconnecting the PCV, my numbers were re-checked and they were essentially unchanged. I saw a tiny shift in MAP and AFR as expected and about a 30 RPM increase in warm idle.

Packwood National Tour

The Packwood Tour event was awesome as usual.  I learned a lot.  Basically I ran out of guts where I should have kept the hammer down in a lot of spots. My times were way off the pace Saturday.  Sunday was better, but I'm still off the pace. My idle is still having issues when the car is hot, but I can get it restarted now if it stalls.  Time to work on the EHPS conversion.

EHPS Conversion

My power steering is an issue.  It constantly pukes fluid and I want to get some weight off the left front and move it to the right rear.  I'm currently running a diaper on my reservoir to catch the leakage.  I considered de-powering the rack, but with the wide tires, I decided that electro-hydraulic power steering was the route to go.