[s-cars] Rebuilding turbos

[Eric Phillips]

> Date: Mon, 15 May 2006 23:44:32 -0400
> From: Eric_R_Kissell at whirlpool.com
> Subject: Re: [s-cars] Rebuilding turbos
>
> Marc,
>
> I have never used a rebuilt turbo. In fact, I have never killed a turbo.
> When I have upgraded, I have installed used turbos.
>
> In fact, I have a used RS2 turbo waiting to install. Maybe I will get
> around to it towards the end of the month.
>
> I do not recall if you said, but is your car chipped? Are you more than a
> mile above sea level?
>
> I would think a K24 in a stock application should last more than 200k miles
> unless someone blew a hose and overspun it or something.

Hi, Eric (you're the other Eric, LOL.)

I have been contemplating the future, and I understand that sometimes,
turbos require replacement.  We are lucky in that our turbos are easy
to access and replace, if necessary.  Not only that, we have a lot of
choices of how to go, in the case we want to hit the slippery slope.
Mild, wild, Happersized stroker plum crazy, etc.

After doing some small amount of research, it seems that folks are
suggesting the head and EM are at their limits with the stock unit.
If you go up in size at all, you need an RS2 EM.  Considering the
bulletproof nature of the rest of the mechanicals, this seems
incongruous to me.  I spoke to Javad at 034Motorsports, and he seems
to think this concern is "B.S."  Now, I will allow that he is trying
to sell stuff.  But like all other low-volume producers, aimed at a
very small market, he can't just shoot from the lip.

In my circumstance, I have a MRC Stage 2 chip and an Apikol FMIC, and
it seems that there is a little room for a small upgrade in airflow.
Such that in the course of a turbo rebuild or replacement, one could
take a small step up without getting into a lean condition at high
RPM, or exceeding the limits of the fuel pump, injectors or MAF.  Or,
more importantly, burned exhaust valves.

I had a Scirocco once - I put on a GTI EM, a modified TB and IM, and a
bigger exhaust.  Within 100 miles of doing all that, I burned the
exhaust valve on #4.  Had the head rebuilt, and it served for another
120k miles before I sold the car.  Obviously, the work didn't cause
the problem.  The problem already existed, and the additional work
pushed it over the edge.  Or it was coincidence.

My experience with that car colors my judgement here, and it might be
that I'm coming to the wrong conclusions.  Other folks on this list
have MUCH more experience than I, and I have to respect that.

I do not know how to get definitive answers on this question -
obviously there are some bad experiences with just replacing the turbo
with a higher-flow unit.  What's the cut-off?  What "higher" is "too
high"?  I don't know.  And I'm not sure anyone else does, either.

But when it comes time, I want to have all the info in hand.  And make
a choice based on as many facts as possible.  Since this list has been
such a blessing in other aspects, I hope that Marc and I can get the
solid scoop on this.

Eric