Low cost options while doing PM on 5ktq (was 10V T pics)

Mon Sep 24 13:30:30 EDT 2001

Here's my delayed but thourough reply to the answers to the questions I
posed earlier...

I received a fair number of great replies and suggestions regarding my
question(s) on doing some additional mods while I'll be performing some
preventative maintenance(turbo etc.) and repair on a leaky manifold gasket.
Since I'll be pulling eveything out on the manifold side, I like to kill
many birds with one stone.

I was inquiring about relatively low cost improvements with repect to flow,
water injection, etc.

Here is some recap, not necessarily in order.

> Of course, everything I've been seeing seems to cost too much.  What mods
> are available for under $1K, if even that much.  I'm not looking to blow
> things out to 400HP+, but getting my 250-300 solid HP without detonation
> risk would be a worthwhile objective.
<< 
 I'd like to know what can be done water injection wise, or  extra fueling.
 Now would be the time if I needed to modify the intake manifold, etc.>>

[Old racing saying " Speed cost$- How fast can you AFFORD to go!?"]  Not
fast enough that I want to pay what I could for a new car.

>That is why it seems water injection should be within reach of budget and
time.

This still seems to be the way to go for me - has anyone done this.  BTDT
suggestions, etc.

More suggestions and my reponses:

#1- better IC will last until the limit of the K-26 $250-400 ( get good with
a mig- parts are $250)

I have not been able to locate a single pass IC for what I consider to be
reasonable cost.  That said, does anyone have one?  Yes I have a MIG welder.

#2- chip and wastegate spring- $300
This has been done and at far less than $300:
http://www.homestead.com/Ben_Swann/qlcc.html
Right now I have things set for 18PSI(combined mods) and now I have reached
the "limit".

#2a- add a compressor by-pass ( if not done all ready) hose and part $50

This is one of the things I plan to do while I'm at it.

#3- send the cam off to Elgin for a re-grind $250

A definate option, especially since Elgin already has a cam to grind for me
and is awaiting my instructions.  Can you expound on the recommended grind.
Why?  I was going to have another 272 Cam ground for another N/A project,
but if getting a cam for the turbo will result in improved performance, that
would be money well spent.

#4- mild port match and polish head/CC/intake $250
I wasn't planning to yank the head this go around, but will certainly clean
up accesible casting flash, etc.  I was considering new lifters - definatley
if a cam goes in.  My last P&P job took a long time, so I didn't want to go
there.

#5-extrude hone the intake & ex.  $600+ ( maybe even the turbine and
compressor housings)

I can do some DIY, but again, don't want to spend too much money or time
esp. if gains are minimal.  What else is involved here.

[Get ya 275 HP and run OK. The CIS is done after that and DO NOT run high
boost
without using the best pump gas you can get ( or AV 100LL) or race gas.]  

This is why I feel water injection is a good option - you dont need to add
gas, just a little water sprayed at proper time and points, and get a pretty
good gain, at least that is what I understand.

[I think to the 300hp range, water injection is unecessary, of course,
adding 
an extra injector or two can help take the edge off of running lean, but 
shouldn't be used to make up large amount of fuel, unless an injector for 
each runner is used (IMO).]

BTDT??? I would like to do this.  How, without spending too much time $$.
How much would it cost to do it right?

[Also, with experience from tuning my car, I am finding that detonation is 
really a timing problem, not a fuel problem.  In my car, I can tune it so 
lean that at 18psi it won't even accelerate, but advance the timing 4
degrees 
and rampant detonation.  I think it is a myth that detonation can be 
prevented with extra fuel-granted, you can dump so much raw fuel in the
comb. 
chamber that nothing will burn, and a richer mixture can help cool the 
combustion chamber and EGT, but if that spark is just a few degrees too
soon, 
it can trigger pre-detonation very easily.

Javad
80tq.com]

I have tightened up on the knock sensor some.  Where can I get a new one for
not too much$$$.  I'm sure my connections are tight, but, sometimes I get
ping and I shouldn't if the knock sensor function is working properly.

[From: JShadzi at aol.com
Date: Sun, 23 Sep 2001 22:12:24 EDT
Subject: Re: boost hoses
To: robert at s-cars.org, lee at wheelman.com, quattro at audifans.com

Yes, proportional, but hardly linear, flow decreases at boost/pressure rises

(just like a fuel pump), and the misconception exists in that fact.  In my 
own car running a K26 (currently), the car is actually faster at 14psi then 
at 18psi- where the inefficient K26 begins heating the intake charge beyond 
the ability of the intercooler.

Javad]

I think I understand what you are saying here - make the engine flow better
and it will accomodate the boost better?

<< Does anyone know at what point the exhaust manifold
 becomes overly restrictive?>>

On the 10v, it is commonly accepted that 275-300hp is the max. realistic
flow 
through the stock MC exh. manifold, frankly, I can't imagine the two-piece
is 
any better, marginal at best.  Also, the k26 is questionable for 300hp too, 
more like 250 efficiently.  They are still both poor examples of a cast, 
restrictive, unequal length manifolds.  Granted, for the stock hp levels, it

is more than good enough.  I am currently working on a five into one tube 
header for 80tq.

I have extra manifold and I don't mind making the holes bigger. I sure don't
want to shell out for some fancy header.

 <<For under $1k, I would look at the manifold first,
 as I will whenever I can afford to take my car over
 the 300hp mark (I'm shooting for 350-375 as a goal).
 Of course, my car is a 3B, so that's not relevant to
 the discussion other than raising the point about the
 exhaust manifold and it being possibly overly restrictive.>>

[Sure, I think it is also commonly accepted that the 3B manifold is also
good 
to 300hp, the RS2 to about 400hp.]

 <<How much flow improvement comes from the '91 200t 2-piece
 manifold, if any?>>

Right, like I said, marginal at best.  I think Jeff Goggin's make shift flow

bench showed about 5-10%, but functionally, the manifold is not much 
different, it just the ONLY option from the factory..

 <<Did you look into MB 6.9 CIS injectors and metering head?>>

What about this - I don't see how it would really make any difference.
Aren't fuel pressures going to be the same at injection delivery point?

Oh, no one mentioned anything about a rising rate fuel pressure regulator.
Yes/No?

 <<How about using a hybrid turbo of some sort to flow more
 air while trying not to have eons of turbo lag? IMHO, the
 K26 boost threshold is unacceptable.>>

[I agree, the K26 is bad, but I feel it is an efficiency issue foremost.  
Problem is, trying the mix and match old, in-efficent turbos does not seem 
that productive to me.  I will be using a Garrett T3/T04E, which is also 
available with the K26 hot side housing for under $800, and only needs some 
adapting of oil and water lines.]

I was going to have a spare K26 rebuilt for around $350.  Is there a better
unit available for not much more?  I mean $600, maybe $800 is reasonable, if
it will definately be an improvement also taking into account longevity.
Also, it sounded like the Garrett requires some retroffiting in addition to
shelling out the dough.

 <<Have you already installed a higher-flow downpipe? Exhaust?>>

[I will be fabricating a 3" downpipe and already have a 3" exh., amazing 
upgrades for the turbo cars (esp. the exh)

Javad
80tq.com]

I just have a difficult time swallowing the replacement of a perfectly good
exhaust - is this thing really the bottle neck.  Also, the work I'll be
doing won't be near the exhaust.  Someone did suggest replacing the cat
though - I wasn't going to go there either, but if it is restricting at the
peril of other components, maybe I need to address now.

Averall, my justification for keeping the costs down so much is that I could
be spending this money on a newer 200 or A6 or ??  Love this wagon though,
so I plan to keep.  However, part of that love is how inexpensive it has
been to operate and maintain - I mean really - this is directed at all of
those who complain about Type$$ issues.  For me it is more of a priority to
maintain the inexpensive but good transportation.  Anything I can do to
improve performance without coasting a couple of house payments, well that
is the icing on the cake.

Thanks everyone  for the help and advice.  I am trying to line everything up
to take the car OOS in the next month or so.  Sorry about the apparently
long rant, but I want to get accross the point of my objectives.

Regards,

Ben
http://www.homestead.com/Ben_Swann/myaudi.html