2 questions, please answer based on fact/personal experience rather than theory.

1. What is the difference between s5 T2 and N/A trannys? Are there any different trannys among the N/As?

2. Does negative vacuum indicate what kind of life your engine has left? If so, what should it read on the negative part of a standard boost gauge (psi or bar). (found a thread with avg. readings, but because of porting, it seems readings were affected)

Thanks,

Jack

 

vacuum is the opposite of pressure. Pressure is positive and vacuum is negative. So, negative vacuum isn't the right term. Negative vacuum is boost.

Vacuum is like reserve power meter. As long as you have vacuum, you will be able to make more power, until you reach zero on the gauge (zero being no vacuum or no boost pressure.) Then the engine is taking in as much air as it can. Once you add a device like a turbo, you can force in more air than the engine can inhale on its own. Hence, forced induction. This, as you know, starts at zero and goes up from there.

Vacuum can't indicate the life expectancy of the engine, but it can tell you its current condition. If the gauge fluctuates at idle, or if its too low, are just a couple signs of a defect in the engine.

 

reminds me ed, you never broughtthat gauge over...

 

What kind of numbers are you guys seeing as "Normal" on your gauges? In normal driving I'm pulling around 10hg in most gears under 3KRPM. (With a high of 15hg under 3KRPM)

I know for a fact my 6ports dont work. (One is stuck open, one stuck shut.) I'm pretty sure that would affect it.

 

Definately, engine is able to suck hella more air with the 6 ports open...

 

The T2 tranny can handle almost twice the torque.
You can spot them by the bottom access plate.

 

sorry, vacuum reading at idle is what i want... when warm of course

 

Warm engine, no loads, at sea level, 750RPM: 15-18"Hg.

For example: TII 90,000 miles, compression 85/90

 

mine sits at 13-15... that ok?

 

Didn't you say you were chasing a vac leak reciently?

One indicator - When you shutdown, it should take slightly more than 1 second for the vac to equalize.

 

nope... no vac leaks.... that i know of

 

My Vac gauge is plugged in AFTER the TB. (This is an N/A)

That should help people read my numbers a bit more :-p

 

IMO anything above 13" i would probably consider normal.