[Tom Vaught]

TEST

Originally Posted by RAIV-Z

Hey Tom, great info. As always the devil is in the details.
1) OIL DRAIN NEEDS TO BE ABOVE THE OIL LEVEL AT ALL TIMES.

• Right. Tough part is to estimate how high the oil level at the front of the pan will be when you deploy the chutes and start braking.

X When you deploy the Chutes and are braking you are: OFF THE GAS, the By-Pass valves are open, the Throttle is closed. The Turbo is in a low load condition on the Compressor Wheel and the Ball Bearing CHRAs can survive under that mode for a bit of time even if the oil is covering the drain tubes. No need to estimate oil level then.

Typical oil drains are installed in Pontiac engine vehicles:
a) 1.0" down from the oil pan rail

• Should I assume this measurement is with a stock style pan?

b) 2.0" inches forward of the first oil pan bolt on the pan. (The timing cover bolts do not count).

• Is this also assuming a stock style pan? The Moroso 2 Piece pan will have the oil level ~5.7 inches below the oil pan rail.

X You have windage in the oil pan, even with a windage tray. The higher up the oil drain is
the more it is out of the crank windage blast. Sometimes a drain that high is tough to do so people weld a "open at the top/open at the bottom "baffle" to block some of the windage effect of the crankshaft. If the hole is a 7/8" drain hole then the "baffle needs to be at least a 1.25" square piece of flat stock shielding the 7/8" hole so windage does not block the air bubbles/oil returning to the pan. Two Turbos, two baffles, and two drains into the pan.

2) The Oil Drain Angle should not be less than 30 degrees downward at all times. Use a carpenter’s level and a protractor. If the angle is too "FLAT" you need a scavenge pump. Hopefully one that will not fail. No valleys in the oil line at all as "a valley" will trap oil and then the Turbo cannot "breathe" and will push oil past the seals on the turbo shaft.

• Got it, mocking up the lines this week.

3) Drain length cannon exceed 18 inches in a downward horizontal direction unless steel line is used with a smooth inner surface. No Corrugated tube crap.

• I believe we’re ok on the overall length, is there a recommended minimum downward angle?

X Like I said above, if the oil pan flange is assumed horizontal and at "0" degrees then the angle from the turbo to the drain inlet needs to be at a greater angle than 30 degrees.

4) Drain lines should be 150% larger than the drain hole size coming out of the Turbocharger.

• Planning on using ¾ lines on each turbo.
X Fine 3/4" id Teflon lines (aeroquip) of steel hard lines work well with a small flex bellows.

5) Minimum of -4 feed line with no restrictors or regulation devices that can stick and restrict oil to the turbos. A .120" oil restriction is allowed right at each turbo inlet fitting to help with high pressure oiling systems.

• Sent a note to Turbonetics asking about oil pressure recommendations/limits for their “ceramic ball bearing” turbos. No response. Also unable to find any related information on their site either.

X The feed line/pressure info above was given to me by Bob Keller who owned Turbonetics for 40+ years. TV

Thanks
Ed