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300rwhp
06-20-2002, 06:39 PM
ok i have a bunch of questions

when your in neutral and rev it up does the boost go up or not
if it does why
if not why
how do blow off valves work
how do you turn up the boost(adjustable boost controller)

thanks

redline
06-20-2002, 07:49 PM
Originally posted by 300rwhp
ok i have a bunch of questions

when your in neutral and rev it up does the boost go up or not
if it does why
if not why


The answer yes and no and it depands on turbo size and engine load.


how do blow off valves work

It basicly a spring / valve. when it gets a vaccum signal it opens

more from www.howstuffworks.com


how do you turn up the boost(adjustable boost controller)

thanks

server differnet ways depanding on the type of wastegate and boost controller but go to the how stuff works web site for more detail

max_boost
06-20-2002, 07:58 PM
Originally posted by redline


The answer yes and no and it depands on turbo size and engine load.

[b]

It basicly a spring / valve. when it gets a vaccum signal it opens

more from www.howstuffworks.com

[b]

server differnet ways depanding on the type of wastegate and boost controller but go to the how stuff works web site for more detail

Turbos are ass:thumbsup:

B18C
06-20-2002, 11:26 PM
Originally posted by max_boost


Turbos are ass:thumbsup:

Welcome to my bandwagon :rofl:

Audi Kid
06-20-2002, 11:53 PM
redline knows to much abought cars :)

Big_Six_Boy
06-21-2002, 11:31 AM
Originally posted by 300rwhp
ok i have a bunch of questions

when your in neutral and rev it up does the boost go up or not
if it does why
if not why
how do blow off valves work
how do you turn up the boost(adjustable boost controller)

thanks

Q1: Probably.

Q2: Why? Cause the activation of the turbo is based on pressure from the exhaust manifold. However, the RPM at which the turbo kicks in varies depending on the size of your turbo. Smaller turbo's kick in sooner and don't suffer from lag so much. This is because smaller turbos have smaller fans, and smaller fans are easier to spin.

Q3: Blow-off valves relieve the excess pressure in the turbo. You don't want to overspin the turbo (150,000+ rpms), so you let some pressure escape (usually during shifts)

Q4: Boost controller? Never used one.. no idea. Sorry. Rage?

rage2
06-21-2002, 12:26 PM
Originally posted by 300rwhp
ok i have a bunch of questions

when your in neutral and rev it up does the boost go up or not
if it does why
if not why
how do blow off valves work
how do you turn up the boost(adjustable boost controller)

thanks

Can't believe I missed this thread...

1. Depends on the turbo size. On MrX's car with a smaller turbo, it'll build a bit of boost when there's no engine load (revving in neutral). On my car, with a big phat turbo, you'll never see any boost in neutral.

2. Blow off valves relieve excess pressure on the intake side when you close the throttle. Without a blow off valve (or cycling valve), when you let off the throttle on shifts or braking, the throttle body closes, so the massive amounts of air the turbo is still compressing slams into a "wall". The blow off valve vents that excess pressure to the atmosphere, and a cycling valve cycles the pressure back through the system before the throttle body. This way, there's not a huge surge of pressure on the turbo which will kill it pretty quickly. You would use a blow off valve if the air measuring device (MAP sensor) is AFTER the throttle body. You would use a cycling valve if the air is already measured at the turbo (MAF, barn door).

3. You turn the knob =). What the boost controller does is control the wastegate, which determines how much exhaust gas/energy is sent to the hot side of the turbo. The more boost you want, the more exhaust energy is routed to the hot side.

A lot of people think a blow off valve controls boost pressure. The wastegate actually controls the boost pressure and turbo speed. You don't want to overspeed the turbo. The blow off valve is to relieve excess pressure that's already built up in the turbo system when you close the throttle.

nookmumracing
06-22-2002, 03:50 PM
Well put rage2!!!!!How's the 944 these days?

Peace

rage2
06-22-2002, 08:15 PM
944's running good. Surprisingly, the engine is the most reliable part of the car right now =).

A-arms, ball joints, wideband O2 sensor, and 911 Twin Turbo brakes are being installed right now.

4wheeldrift
06-22-2002, 09:18 PM
Gonna try the 944 at solo 2, or keep running the slk poser? :D

rage2
06-22-2002, 11:26 PM
With 0 power under 4000rpm, and above that the throttle's like an on off switch, it'll be a bitch and a half to drive around an AutoX course. I might bring it out for an exhibition run someday =).

speedracer
06-22-2002, 11:40 PM
Originally posted by rage2
With 0 power under 4000rpm

Don't need no stinkin' power...it's all mad skillz! :thumbsup: