The BMW UUC Digest Volume 2 : Issue 893 : "text" Format Messages in this Issue: Re: Dinan Chips Re: Dinan Chips Re: Dinan Chips Isetta restoration gone mad
---------------------------------------------------------------------- Date: Mon, 12 Dec 2005 17:05:04 -0500 From: Ben Keyes <[EMAIL PROTECTED]> To: UUC Digest <bmwuucdigest@uucdigest.com> Subject: Re: Dinan Chips Message-ID: <[EMAIL PROTECTED]> under-calling is relatively common I think. it's relatively common knowledge that the 3.2l US M3 motors were more like 250-255 as compared to the advertised 240. there have been a number of mis-steps made by Mazda (1.8l Miata & RX-8 IIRC) as well as the big to-do about the "320" hp Mustang Cobras. consequently there's little point in (or chance to get away with over-calling the numbers any more. under-calling was the norm with Japanese market cars until the last year or two with their gentleman's agreement to not exceed 280hp JIS net, which is 276hp SAE or something like that. I forget how it converts to euro DIN ponies, but it's close to ours. a new SAE testing procedure was rolled out recently & in some cases it resulted in _higher_ numbers, most prominently the new Cadillac STS-V which gained something like 25 hp to 469 or so. use of the new procedure is voluntary at this point but I think it is required for new engines on sale after some date. A friend had some dealings with people at BMW Mfg in SC and they said the "standard" figure of 15 or 18% was way too high, esp when high hp was involved (he has a Mod car). I know from personal experience at my last job that there's a significant under-calling in some of our engines, for various reasons. with the easy access to dynos which exists today, most anything new of any interest ends up on a dyno in a matter of days of going on sale. witness all the dyno runs of the new ZO6 which were posted in the first few weeks they were on the market. in those cases there's a very well defined level of loss involved in the drivetrain as well, since there is engine dyno history which can be used to baseline a particular drivetrain combination to establish a nominal correction factor. Ben former engine plant finance weasel Paul wrote: > This is just my point. BHP numbers (especially > directly from the OM) are not particuarly meaningfull. > I don't think anyone here would argue that your E46 > has only a 7% drivetrain loss. The reality, of > course, is that the BMW engine numbers are underrated > (there was a big stink recently about how Toyota was > overrating their numbers or at least "maniputulating" > them). Now, how meaningful would it be for a chip > manufacturer to then compare their chip's performance > on a chassis dyno and then converting them to to BHP > using a 18% drivetrain loss factor??? WOW, an instant > 11% performance upgrade without changing ANYTHING. ------------------------------ Date: Mon, 12 Dec 2005 15:01:59 -0800 From: [EMAIL PROTECTED] To: bmwuucdigest@uucdigest.com Subject: Re: Dinan Chips Message-ID: <[EMAIL PROTECTED]> Tire pressures affect the conversion factor. I'm willing to bet that, in general, the places that run dynos don't bother checking the customers' tire pressures before they do their runs. And I'm willing to bet that most of them don't know how to adjust for different tire pressures, even if they do check them. Depending on the type of dyno and who you ask, you can get conversion factors for BMWs ranging from 12% to 19%. Scott Miller GGC BMW CCA >Date: Mon, 12 Dec 2005 09:41:53 -1000 >From: Jay G <[EMAIL PROTECTED]> >To: bmwuucdigest@uucdigest.com >Subject: Re: Dinan Chips >Message-ID: <[EMAIL PROTECTED]> > >so i'm guessing to get higher numbers on a dyno, the tire pressures need >to be higher...any general rule as to how much tire pressure to run on a >dyno??? > >[EMAIL PROTECTED] wrote: > >>It also is not affected by tire pressures, which >>apparently is a bigger variable than one might think. >> ------------------------------ Date: Mon, 12 Dec 2005 14:49:07 -0800 From: Mark Dadgar <[EMAIL PROTECTED]> To: bmwuucdigest@uucdigest.com Subject: Re: Dinan Chips Message-ID: <[EMAIL PROTECTED]> On Dec 12, 2005, at 1:20 PM, Marco Romani wrote: > I remember when this happened and went and looked at the dynapack > and how it > is installed/used. I honestly can't say how it would damage wheel > bearings. The wrong wheel offset can and will eat wheel bearings. Is the effective wheel offset when the Dynapack is connected the same as stock? - Mark ----- [EMAIL PROTECTED] Check out my JustRacing Home Page at: http://www.justracing.com/homepage/mdadgar ------------------------------ Date: Mon, 12 Dec 2005 14:34:02 -0800 (PST) From: Matt Weimer <[EMAIL PROTECTED]> To: bmwuucdigest@uucdigest.com Subject: Isetta restoration gone mad Message-ID: <[EMAIL PROTECTED]> I thought this to be an interesting application of an Isetta chassis. http://www.microcarmuseum.com/tour/whattadrag.html Matt Weimer Hoosier Chapter __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com ------------------------------ End of [bmwuucdigest] digest(4 messages) **********
