hellbents10

iTrader: (10)

A couple inches away is ok, weld on a npt bung and run a couple feet of copper tubing, then you can go to silicone or nylon for the run to the boost/air pressure gauge.

Wilde Racing

iTrader: (26)

thread from the dead again, but why would it matter where the gauge is mounted? Take my STS truck for example. I have a back pressure gauge mounted in the rear 02 sensor port, why would it read any differently if it were closer to the turbo?

cbr600rx7

iTrader: (12)

Great read.

Vetal

iTrader: (3)

Does intercooler affect exhaust backpressure too? If I have very small restrictive turbo, will better intercooler help with backpressure and power?

engineermike

Oddly enough, adding an intercooler when you don't have one will not lower exhaust pressure, but upgrading to a less restrictive intercooler will lower exhaust pressure.

Edit: Now that I think of it, a 0-restriction intercooler will actually add a tiny bit of exhaust pressure due to increased mass flow through the compressor and the corresponding drive pressure needed by the turbine.

Vetal

iTrader: (3)

On the other hand, it would require less drive pressure if pushing same amount of air requires less work for compressor, right?

engineermike

If it's the same amount of air at the same boost pressure, then it's the same drive pressure. However, adding an intercooler adds restriction to the cold side and also increases air mass flow rate, both of which increase compressor required hp and, thus, exhaust drive pressure.

Vetal

iTrader: (3)

I was talking about switching to less restrictive intercooler, that should in theory lessen drive pressure for the same HP

engineermike

True, but less drive pressure does result in more hp for the same boost.

Oddly enough, something like a maf delete or bigger throttle body actually helps power on a turbo car by lowering drive pressure. It's counterintuitive but the end result is still more power. It works different on a supercharged or na engine.