REFLECTOR: Turbo concerns

[Scott Derrick]

You definitely have something not working in your turbo setup. I'm 
assuming you measuring upper deck pressure?  Ala intake pressure after 
the intercooler and servo?

problems.

1.) turbo is not spinning freely due to internal obstruction(I've seen 
rags), bad or incorrectly installed bearings, bent fan, etc.  It should 
spin very freely by hand, take a long time to come to a stop. Blow a 
vacuum cleaner through the turbo and see how she spins, with an open 
turbo(no back pressure) it should spin up very fast with a large 
canister style vacuum.

2.) waste-gate opening prematurely. In your case immediately. Can you 
see the waste-gate operation when the engine is running? Make bright 
marks on the moving parts to make this easier.  Note its position before 
start, then at idle, then a varying degrees of throttle position. It 
should be completely closed until close to mid throttle. At least the 
tio520 operated in that manner.

3.) pop-off opening too soon.  Tie a rag or something to the opening 
that will flutter around when it opens. Do this at the same time your 
observing the wastegate.

4.) If all the above are OK, its possible your intercooler is 
restricting flow. remove the intercooler and run without it.

Scott


-------- Original Message --------
Subject: REFLECTOR: Turbo concerns
From: Chris Barber <cbarber at texasattorney.net>
To: REFLECTOR <reflector at tvbf.org>
Date: 08/20/2012 07:18 PM

>
> As I have mentioned I have had what I think are incongruent readings regarding my manifold pressure (mp)and engine rpm. It seems I am getting quite low mp as I add power to higher rpm.
>
> I am not well versed in this area but my thought is that as I add power, even with slight boost (currently using a 3 lb spring in my wastegate) eventually my mp should raise a bit more.
>
> Today I did some static test. I recorded engine RPM with the  turbo hooked up and recorded the mp at 1000 rpm increments. Then I removed the turbo plumbing from my intake and recorded the same info My results currently confuse me.
>
> With the turbo hooked up I am getting
>
> RPM.   MP inches
> 2000 - 14.0
> 3000 - 15.5
> 4000 - 19.3
> 5000 - 21.6
> 5700 - 24.5 (topped out)
>
> With the turbo removed.
>
> 2000 - 15.8
> 3000 - 15.3
> 4000 - 19.7
> 5000 - 24.8
> 5833 - 29.8
>
> Is this indicative of restriction in my plumbing? Perhaps in the inter cooler? A dirty air filter? A bad pop off valve or a leak not allowing the air pressure getting to the intake. Or????
>
> I am uncertain what other permitters I need to check and provide. I am just starting my diagnosis in my Phase One testing. I only have 1.6 hours in the air so far. I value ya'll's direction and input.
>
> Heck, perhaps this is working properly but it just doesn't seem right/comfortable.
>
> Thanks folks.
>
> Chris Barber
> Houston
> Velocity SE
> Rotary 13b turbo (?) :-)
>
> Sent from my iPhone 4
> _______________________________________________
> To change your email address, visit http://www.tvbf.org/mailman/listinfo/reflector
>
> Visit the gallery!  www.tvbf.org/gallery
> user:pw = tvbf:jamaicangoose
> Check new archives: www.tvbf.org/pipermail
> Check old archives: http://www.tvbf.org/archives/velocity/maillist.html
>

-- 
Man must evolve for all human conflict a method which rejects revenge, 
aggression and retaliation. The foundation of such a method is love.
Martin Luther King Jr.