[s-cars] Your TT posting

[colin cohen]

Yes it is legal and we do that running different sizes.  But I take your point as I have run rain Hoosiers on the rear of my A4 in wet track/drizzle conditions with some success.  But its hard to manage a whole lot of tires especially when you there are long tows involved.  So what we need to do is find a compound split that is effective by trial and error and then leave those rears on the car until they expire.  We find the rears last 8 to 10 sessions as compared with 2 or 3 from the fronts.  On my A4 the rears will last the whole season !  They also spend a bunch of time airborne !

The ducting on the TT is pretty good.  It was the first thing we checked to try and get as much air from the small intakes to the i/c and the radiator.  We have also flowed the air going out of the i/c which is something Audi started with the S4 V6 but we do have more work to do here to deal with the compromise between the integrity of the i/c and airflow as its very very close to the tire and we run the risk of coating the rear with rubber and stuff if the airflow path is too unbaffled.

AFAIK the haldex cannot be locked.  You can adjust the split with software mods to the box.   So are you suggesting that there is something that can be done if we open it?  I had never heard of that possibility and would dearly like a 65/45 fixed R/F split.

C.
  ----- Original Message ----- 
  From: QSHIPQ at aol.com 
  To: ccohen5 at compuserve.com ; larrycleung at gmail.com 
  Cc: wenoland at pacbell.net ; s-car-list at audifans.com 
  Sent: Tuesday, April 24, 2007 10:07 PM
  Subject: Re: [s-cars] Your TT posting


  As I suggested to LL, you might try running different rubber front and rear, that's legal.  The race stuff up front and something less sticky rear.  Did this on the GLH turbo with great success.  I'd also seriously consider a rear bar delete and give it a try.  When I do chassis tuning, I use a ganalyst or a gtech pro meter and a IR temp guage.  Also, make ALL the air going to the intercooler and radiator go thru it.  I have an SAE paper that shows something like 30% improvement doing nothing else to the radiator but sealing leaks.

  I actually enjoy the stock rules myself, it really makes you pay attention to things you'd otherwise just dial the boost up to overcome.

  Have you tried getting the haldex to just lock?  Remember that a locked center has ideal brake force distribution and torque follows weight distribution and turning radius both.

  I think you have room to play, and be within the rules without resorting to 50psi tire pressure.

  SJ