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David I just bought one of their complete kits, gauge (red display) and probe, used the 1/8 NPT (TC-KEGT-NPT ) probe and drilled and tapped the manifold about 130mm in front of where it comes out of the turbo,right on the bend. I'll stick a pic up in my album. I had a NPT tap but they also sell a probe with a 1/4 BSP fitting as well. Very easy to drill and tap the manifold it's about 3/16" thick.

I drilled and tapped the inlet manifold to fit the boost gauge as well, just did it right on top towards the front.

David pics are up, think it might be less than 130mm from turbo looking at the pic, was just above the number cast onto the manifold anyway.

Peter  interesting  topic but could you tell me if the fitting instructions for the probe stated  the exhaust manifold is a prefered point and I ask this because with all the trucks I have had any thing to do with the probe has been fitted on the outlet side of the turbo in the exhaust to muffler section within 6inches of the turbo. I have refrained from fitting a pyerometer to mine because I could see I would probably have to fit a new exhaust line and this one will probanbly last a fair while but might not take to kindly to drilling and then welding the probe holder in place .

Cheers Dave 

Dave I was told to mount the probe within six inches of the turbo outlet which in the Oka's case is a cast manifold which is then connected to the exhaust.

Any further away from the turbo and there is too much temperature drop to make the readings meaningfull.    As it is the combustion temps seen post turbo would still be far less then the cylinder temps.

Peter you have got it spot on I misinterpreted your explanation and to be honest I forgot about the cast manifold on the outlet side, your fit should be fine .

Cheers Dave

>> All I can say is if you are wondering about any effect on your Oka, take the aircleaner lid off and try it, some report big differences, some not, then remove the aircleaner and take it for a short run in a "clean" area and see what a difference it makes <<

I finally got to do that yesterday. A friend has a PerformanceBox, which we attached to the windscreen and in our limited time available, did four runs along a flat stretch of freeway. The standing start was achieved from the emergency lane, and despite light rain, two of OKA's more questionable joys were employed: we didn't suffer any wheelspin, and we didn't break the speed limit.

The first two runs, one north and one south but in virtually no wind, were in standard trim. Times from zero to 400m were 30.44 seconds at 74.3km/h, and 33.22 seconds at 66.5km/h.

For the second two runs the air cleaner lid was removed and the large air cleaner taken out. There was immediately heaps of induction noise that I don't normally have, so evidently the sealing that I do have is good (although I don't have a rubber seal on the outer lid). Times were 30.68 seconds at 71.7km/h, and 30.00 seconds at 74.86km/h.

Make of that what you will!

Hal

I would really like to see someone try the same thing with the outer in place and the inner filter removed. I have been thinking that the inner filter was the Achilles heel as it has a much smaller surface area for the air to move through.

The Oka is the only 4wd that I am aware of that uses a safety filter, it is normally limited to earthmoving machinery and large trucks but in these vehicles the filter assy is sized appropriately but on the Oka it seems to be a bit marginal.

Pete

Hal reported --

"The first two runs, one north and one south but in virtually no wind, were in standard trim. Times from zero to 400m were 30.44 seconds at 74.3km/h, and 33.22 seconds at 66.5km/h.

For the second two runs the air cleaner lid was removed and the large air cleaner taken out. ...Times were 30.68 seconds at 71.7km/h, and 30.00 seconds at 74.86km/h."

Second run may have been little wind, but either a fair breeze or different driving techniques in the first test. Wind direction must have swapped between the tests as well.

Maybe inconsistent driving technique might explain all of it ;-))))

Still,  if you do a straight average of each set of two runs, for the 400m, time was 1.5 seconds less and final speed was 2kmph faster without the filter - not earth shattering but hardly trivial either.