[s-cars] Re: wrt pushing RS2 to the edge...

[Mihnea Cotet]

Sorry, I meant "I can't but insist" but wrote "I can't but exist" instead...

Mihnea

At 18:43 10/05/2003 +0200, Mihnea Cotet wrote:
>Scott et al.,
>
>
>28 psi *does* gain over 26 or 21 in terms of torque IMHO/IME (I can't but
>exist on the Experience part, especially in tuning myself a few RS2 engines
>recently).
>
>And, I know of several RS2s running 28 psi (i.e. almost 2 Bar boost or PR)
>overboost for a massive 530-540 Nm of torque (dyno measured), while stock
>RS2 torque is 420 Nm at max. 1.4 Bar. I know 28 psi isn't efficient, but
>for torque no one needs 100% efficiency. So what does your statement of 28
>psi being almost double the factory boost levels mean? Stock AAN boost?
>Maybe, okay but what's the point? What's the point in comparing apples with
>oranges?
>
>So, sorry to insist, boost means torque and if timing is properly
>programmed (sorry to insist on that point again), 28 psi will be a lot of
>times better than 21, I've personnally BTDT many times.
>
>Then, according to several serious tuners here in Europe (what do you say
>of Dupre Motorsport's racing engine management director during the 90's?
>He's the guy that helped me with most of what I know about chip tuning),
>stock rods (including the crappy AAN units which are the worst Audi ever
>used, i.e. the thinnest) are known to break at 600 Nm crank torque, meaning
>in excess of 2.5 Bar or PR. This also means that running 30 psi (or 2.0 Bar
>or PR) won't break rods, except if the timing/fuel chip is done by an a$$
>and if knock sensor function is suppressed or the threshold raised.
>
>Furthermore, maximum boost people are stating doesn't mean anything to me
>in terms of HP, what boost levels are you guys seeing at 5500, 6000, 6500
>and 7000 RPM? This is more relevant than maximum boost you see for a few
>seconds during overboost.
>
>HTH and my 0.02 Euro,
>
>Mihnea
>
>At 12:27 10/05/2003 -0400, QSHIPQ at aol.com wrote:
>>Hmmm...  I personally think running 28psi on an S-car is silly (I'd say
>>stupid, but long nerdy posts about effective compression ratios I don't
>>need).  IMO, you are "safer" increasing the Density Ratio than the
>>Pressure Ratio.  I'd also venture to say that 28psi probably isn't gaining
>>any performance over 26psi, which means Motronic is probably saving a lot
>>of butts here.  I'd also venture to say that the difference between 24psi
>>and 26 psi is barely measureable.  I'd also venture to say that the
>>difference beyond 21 psi (RS2 equipped only) comes at a massively
>>diminishing rate of return.
>>
>>I'd further venture to say that rods are known to pop at 30psi, which
>>means the closer you get to it, the higher the danger.
>>
>>All anecdotal "evidence" so noted, 28psi is almost double the factory
>>boost levels.  For street driving, probably not there long enough to worry
>>about it.  The long straight and intense 30minute track session?  I'd be
>>worried about it.
>>
>>Boost, specifically Pressure Ratio, is only part of the equation in tuning
>>for performance gains.  Cars *can* run at maximum parameters, but small
>>hiccups in any of the ancillary systems can cause catastrophic failures
>>because of boost.  The good news Joe, is that you can respond in the
>>"takes one to know one" concept.  Specifically, if it's stupid to run
>>28psi, in reality, with no other changes, it's really no "smarter" to run
>>it with race gas.
>>
>>HTH and my .02
>>
>>Scott Justusson
>>
>>
>>In a message dated 5/10/2003 8:07:52 AM Central Daylight Time,
>>mik at info.fundp.ac.be writes:
>>
>>Joe,
>>
>>Someone stating 28 psi without race gas on an RS2 motor is stupid simply
>>doesn't know what this motor/turbo is. Period.
>>Then, you can log timing advance and IAT with VAG-COM, I don't remember
>>where exactly but you can.
>>
>>HTH,
>>
>>Mihnea
>>
>>At 05:00 10/05/2003 -0400, Robert Myers wrote:
>> >--
>> >[ Picked text/plain from multipart/alternative ]
>> >At 08:16 PM 5/9/2003 -0700, Joseph Pizzimenti wrote:
>> >
>> >>Well, this was sparked by a rather vocal argument I
>> >>had with someone about water injection recently.  I
>> >>was asking his advice and he has experience with B5
>> >>S4's and 3000GT VR-4's, etc...he basically said I was
>> >>stupid to run 28psi without race gas.
>> >>
>> >>Is there any way I can datalog ignition timing or
>> >>intake air temperature with VAG-COM?
>> >>
>> >>Joe
>> >
>> >
>> >I dunno, Joe, but I betcha you could get an answer on the VAG-COM list.
>> >
>> >Mailing-List: list VAG-COM at yahoogroups.com; contact
>> >VAG-COM-owner at yahoogroups.com
>> >
>> >
>> >
>> >
>> >____
>> >
>> >I've been wondering...  Who would Jesus bomb?
>> >
>> >Bob
>> >*****
>> >  Robert L. Myers  304-574-2372
>> >  Rt. 4, Box 57,  Fayetteville, WV 25840 USA  WV tag Q SHIP
>> >  '95 urS6 Cashmere Grey - der Wunderwagen   ICQ 22170244
>> >  http://www.cob-net.org/church/pvcob.htm
>> >*****
>> >--
>
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