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Re: can't get it into 1st when rolling faster than 10mph

To: mrc01@flash.net
Subject: Re: can't get it into 1st when rolling faster than 10mph
From: Bill Hamburgen 650-617-3329 FAX -3374 <billh@pa.dec.com>
Date: Mon, 08 May 2000 14:19:59 -0700
> I do heel-toe downshifting without double clutching, and heel-toe
> starts (on hills for example) all the time. My feet are so wide
> that I don't need to rotate my foot to do it. 

I'm a size 13 too, so I can relate.

> Unfortunately, adding the double-clutch to get into 1st doesn't always work.

Hmmm.  If it does work sometimes, perhaps practice might help.  Getting 
the size of the throttle blip right was key as I recall.  Too much or 
little and the gear speeds aren't matched closely enough to engage easily.  

> I suppose I should take the car in and get the transmission fixed
> since it's under warranty, but haven't gotten around to it yet.
> All the other gears shift just fine and it's rare to need 1st
> while moving, so it's been a low priority task.

Yeah, Michael.  Makes sense.  This is the sort of thing I usually like to 
get serviced just a couple of months before the warrranty runs out, in the 
hopes that the latest parts will be better than what the car was built with. 
I'm sure there are folks on the list that would know if this is a common 
problem and/or if there have been any service bulletins on it.


/Bill


> Bill Hamburgen 650-617-3329 FAX -3374 wrote:
> > 
> > Michael,  Have you tried double-clutching?  You'll probably find
> > that lugging in 2nd gives faster times, but it's nice to be able
> > to grab 1st if you really need it.
> > 
> > Just in case you're not familiar with the practice, a double-clutch
> > 2nd-to-1st downshift is done as follows:
> >   1 - push in clutch, shift 2nd-to-neutral, release clutch
> >   2 - blip throttle momentarily (to match revs in next lower gear)
> >   3 - push in clutch, shift neutral-to-1st, release clutch
> > With a little practice, it can be pretty quick.  If your pedals are
> > positioned and adjusted correctly, you can can use the ball of your
> > right foot to brake while you use the right side (or heel) to blip
> > the throttle.  This is the "heel-and-toe" manuver.
> > 
> > I used to be really good at this when I owned a 1955 Porsche with
> > a tired 1st gear synchroniser.  The car had lived the first 10
> > years and 30k miles of its life in the US Virgin Islands.
> > 4th gear was indeed virgin.
> > 
> > /Bill
> > 
> > --------------- forwarded message ----------------------
> > Date: Fri, 05 May 2000 16:24:00 -0700
> > From: "Michael R. Clements" <mrc01@flash.net>
> > Subject: Re: best line
> > 
> > Sure, the rear end ratio would be included if one is measuring
> > the total gear ratio from the crankshaft to the wheel. That would
> > be the transmission ratio multiplied by the differential ratio.
> > For example, in my RX-7 1st gear is 3.483 and 4.1, which amounts
> > to 14.2803, which means 225 ft. lbs. at the crank is converted to
> > 3,213 ft. lbs. at the wheel. Incidentally, divide that torque by
> > the wheel radius, divide by the mass of the car and you have more
> > than 1 g of acceleration in 1st gear which thanks to lofty rotary
> > redlines goes to just over 40 mph.
> > 
> > Too bad I can't get it into 1st when it's rolling anything faster
> > than 10 miles per hour.
> > 
> > --------------- end forwarded message ----------------------
>
> Michael R. Clements
> mrc01@flash.net




Bill Hamburgen - Senior Member Technical Staff
Western Research Laboratory
Compaq Computer Corporation
250 University Avenue
Palo Alto, CA 94301
        Phone:    1-650-617-3329
        FAX:      1-650-617-3374
        e-mail:   bill.hamburgen@compaq.com -or- billh@pa.dec.com 
        project:  http://www.research.compaq.com/wrl/itsy




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