The Alchemist

iTrader: (19)

Of course the analytical scientist in me had to analyze the data I generated on the dyno and forecast what my boost should have been.... so a little Excel and I have this...



As you can see, my boost was pretty smooth and linear till about 4800-5000 rpm then it became a mess, which from playing with the pressure on the air compressor, sounds about right. When I turned it up to about 14-15psi is when the air just starts blowing out of both the iat sensor and the bypass valve really loudly.

stevieturbo

The leak out the air temp sensor wouldnt make any difference, in the overall scheme of things it would be tiny.

The valve could well be a different story though. And because your test cant take account of pressure drop vs flow across the intercooler core....good chance you have less pressure holding it shut in normal use, than you would do with a static test.
So it probably leaks more.

The Alchemist

iTrader: (19)

Well, the way I look at it is that in an centrifugal supercharger setup, air is power, and any air leaking, is air that's not being used to make more power. I know it's hard to quantitate exactly how much air is being pushed out of the valve and IAT sensor, but it's a fair amount, and I'm excited to get them fixed.

ajrothm

Also check the volute on the Procharger and make sure it is not leaking thru any of the bolt holes that you are NOT using. You should have set screws (Allen screws with no heads) screwed into those holes to prevent boost leaks.

When you pressure up your system, soapy water the head unit and look for leaks. You'll definitely find some. Slight as they may be, there will be leaks. Mine leaks slightly between the volute and gear case. Also check your blow off valve. Even with pressure applied to the top side of the valve, my original Procharger BOV leaked some.

Once again, probably nothing measurable but... I'll take what I can get.

RONSBLACK1998TA

I used a stock IAT sensor from a turbo buick grand national. I had a welded bung on my charge tube just before the throttle body. That was done previously by the person I bought it from. Never had an issue. Also if the sensor ever goes bad, it's easy to find a replacement.

The Alchemist

iTrader: (19)

Well, I discovered the blue rubber weather pack seal on my IAT sensor is missing. So it's not only leaking out the rubber grommit, it's also leaking out the sensor itself as you can hear in the video when I take the plug off. That won't be an issue with the new sensor since it's a sealed unit. Again, any air leak is lost power potential.

I never thought about the extra bolt holes in the head unit. I have two open ones that I need to get sealed I guess. I pressure tested the system after the blower, so next time I'll test it with the hat off and pressurize the blower itself. The leaks out of the bypass valve and iat sensor were so loud, I couldn't here any other leaks. Once I get those two items fixed (parts will be here tomorrow, then off to my buddy to weld), I'll then repeat the test and see if anything else is leaking.

Exactly. The way I look at it, is if the blower is working to move the air, it should be ingested by the motor to make power. It's not like in a turbo setup where you chose how much boost you want to make and then push out the rest, I'm greedy, I want every last cfm of air to go into the cylinders to make power.

MillsMotorvation

Yes any leaks are not good, but I know the little ones are not that bad. The less leaks the less the unit got to work.