[urq] Urq, WX, Head Problems, etc.

[Steve Eiche]

Those 75lb or even 65lb injectors are way too big. I think the guys 
running 600+ on 20Vt MIGHT use them, but I can't imagine using them on 
even a pretty highly tuned 10V.  How did you arrive at needing those 
values? The 46lb injectors should be much more than you need for 350 hp 
at the wheels.  Getting those big ones to idle properly and go closed 
loop properly will likely be a challenge.

If you are going for 300+ you should be running individual coils or a 
high performance aftermarket ignition, like an MSD at the very least. 
Otherwise, I will bet that you will be pulling that engine apart again.

Steve

Stephen Redford wrote:
>  
>  
> -----------  Steve , I am running the M.S. with their Spark program.    
> We did , in fact , get detonation with that program with the original 
> 7;1 stock pistons,  Apparently on one of the first dyno runs with the 
> new header, turbo and intercooler,etc.  The Boosst Controller =not a 
> manual- was hooked up wrong and somewhere in the mid rpm range boost 
> spiked to 27 or 29 Lbs.  before the shop owner could shut it down.   
> Burned pistons and total engine rebuild is the result, that is why the 
> new pistons are 8.5;1.   Closer to other Audi's stock ratios    The 
> injectors were from O34, part of a kit which I did not use. They were 
> Ford truck  46lbs.  Shop  owner was sure the injectors were at fault , 
> so I had them  checked... They were dead on spec.  The shop owner said 
> he had been running a very high - near max somewhere -  Duty cycle .   I 
> have decided to get some Siemens 65 or 75 lb. injectors for the rebuild 
> .  I am looking forward to a better result this time.  We are shooting 
> for approx.  300++ at the wheels.   The turbo is rated for 396 from 
> Blouch Turbo.   The shop owner told me that some part of the very latest 
> version of Mega Squirt does not run some part of a 5cyl. engine.  So 
> this is the latest minus one or two editions, but it does have the spark 
> code.   Thanks for your input!  Thanks to all who have replied   ...Stephen
>  
> 
>     ----- Original Message -----
>     *From:* Steve Eiche <mailto:seiche at shadetreesoftware.com>
>     *To:* shr42 at msn.com <mailto:shr42 at msn.com> ; urq at audifans.com
>     <mailto:urq at audifans.com>
>     *Sent:* Saturday, May 19, 2007 9:29 AM
>     *Subject:* Re: [urq] Urq, WX, Head Problems, etc.
> 
>     Are you still running the MAC-02 for timing?  The reason that I ask is
>     that IME, you will need some serious retuning of the ignition maps with
>     increased boost and 8.5:1 compression or you are going to have big
>     detonation problems.  The stock system is all wrong for that
>     configuration. You will get it to run OK off boost, and on when it is
>     cold, but once the intake temps get high the stock maps can't handle it
>     and even to tune it properly you need to sacrifice some performance to
>     keep it safe.  You will also likely have pinging at ~3k RPM on the
>     transition to boost that will need to be taken care of.
> 
>     Hopefully you have the Megasquirt 'n Spark so you have a better
>     ignition
>     system and control.
> 
>     Steve
> 
> 
> 
>     ------ I have been having some work done on my '85urq.   While on the
>     dyno, after parts had been replaced and fab'd, etc. ,  there was
>     detonation..  The engine is now apart.  Pistons have been purchased,
>     (Wisco) and the head and block or at the machinist.   The machinist
>     says
>     that the valves and guides are out of tolerance and need replacement .
>       Also , the cam journals are not properly aligned and must be rebored,
>     (approx. extra  $190.). The shop mechanic handling everything suggested
>     a new head or equivalent .     What would be an equivalent replacement
>     head and approx.  cost to make it fit...?    I am thinking that I would
>     be better off just continuing with the existing head repair, even
>     though
>     the machinist says it might now go thru another  rebuild as it has
>     already been worked on previously.   So the present repair , he
>     suggests
>     , would likely be the last one...   I have already had a front mount
>     intercooler installed , bought a new turbo, had a tube header made, new
>     down pipe, EFI (Megasquirt) and new Ron Davis Radiator, and other
>     related details.   I had thought of getting a 3B engine and having him
>     install it, but that would probably cost a lot more and many or most of
>     the current parts would not fit.    I sure would appreciate some
>     suggestions and "how to's" to make my decision.   Another head might
>     need new valves and guides and new lifters and would cost to ship, from
>     wherever and cost to be disassembled , manifolds might not fit, etc. ,
>        So I am thinking ;  just repair what I have and get the car on the
>     road.   Thanks in Advance,    Stephen Redford  '85Urq  Seattle
> 
> !DSPAM:1002,464f4fd4875151295562001!