A big blue trail of smoke perpetually follows my car now. Turbo could use a rebuild, but I'm going to upgrade instead.

After a lot of map searching, I've come up with this - it's a T3/T04E 46 trim. I'm planning on 14.7 psi, but will be stuck around 8-10psi until my engine is built. What does everyone think of the following?



Give me your thoughts, thanks.



- Interior FAQ -
J-Body of Michigan -

Oh come on.. Blue smoke is good.

+10 hp for every second the smoke lingers around after you've left.







Club Vantage :: importfighter.ca :: RIP Trux0r...

Oh man, if only. Add that onto what I was pushing at 8psi and that gives me like 500 whp, hahahaha

I've been searching around and it's difficult to find for a decent price, so I'm going to go with a T3/T04E 57 trim. Not too much difference - it'll take a little longer to spool.





- Interior FAQ -
J-Body of Michigan -

Damn. I thought this had something to do with clubbing pups.

I have no idea how to read those graphs... But they look cool







Club Vantage :: importfighter.ca :: RIP Trux0r...

Kevin: Good one.

Jeremy: They're compressor maps. The map itself is similar to a map with elevation lines. The concentric "rings" here are different levels of efficiency for the turbo, with the center being it's most efficient range (in terms of amount of heat produced, to put it bluntly).

On the bottom you have airflow measured in pounds per minute. Using a mathematical formula you can calculate what kind of airflow an engine at any given volumetric efficiency.

On the left, you have a pressure ratio. 14.7psi is atmospheric pressure at sea level. Measured as a ratio, this is 1. To find the ratio you take (atm+additional psi)/atm.

So if you want 10psi, you add 10 to 14.7 (and get 24.7). 24.7/14.7 = 1.68 approx. Therefore, the pressure ratio for 10psi is 1.68.

So I took a horizontal line from 1.68, and drew it across to intersect with values for my airflow at 3500, 4500, and 5500 rpm. Turns out that upon further inspection, that 57 trim should be more efficient at 14.7psi, because my car loses 2000 rpm per shift (6500-4500).

fun

get Corky Bell's book, Maximum Boost. It explains much better than I can.



- Interior FAQ -
J-Body of Michigan -

That's actually a pretty good explanation... I get it now...

So the 57 trim turbo would be more efficient at higher RPMs at 14.7psi? Am I reading that right?







Club Vantage :: importfighter.ca :: RIP Trux0r...

bingo

glad to hear my explanation made some iota of sense.



- Interior FAQ -
J-Body of Michigan -

Hey guys... just wanted to give you an update.

My new turbo is on the way. I decided to go with the T3/T04E hybrid, 57 trim w/ a .63 AR turbine.

Pictures when it gets here!



- Interior FAQ -
J-Body of Michigan -

^^That seems like a much better choice should give you boost at about 3500 or so



1989 Turbo Trans Am #82, 2007 Cobalt SS G85