Boy John that isan interesting bunch of data, the whole transmission
thing looks like less than 1% difference thowing out the T400. Looks like
this is more than academic considering the money you have spent looking for
the answer. I think you could make an argument that 1% difference is within
a margin of error, so the best choice for a particular car look for
dependability and spend your money on rear gear ratios and the motor.
Basic rule, try to run no converter if an automatic and don't consider the
T400, in most cases I would think the automatic would be the cheapest and
most dependable. If a person wanted lots of gears using "Gear Venders"
over-under drive bolted to the back of their automatic would be dynamite and
they claim to be able to handle more hp than most of us have. What do you
guys think, as if I need to ask. L> Kvach Butters
----- Original Message -----
From: John Beckett <landspeedracer@email.msn.com>
To: dahlgren <dahlgren@uconect.net>; The Butters Family <bbutters@dmi.net>
Cc: <Land-speed@autox.team.net>
Sent: Wednesday, August 30, 2000 9:18 AM
Subject: Re: Bonneville Transmissions
> Don't know if this proves Dave's point or not. Based on the data I have
> collected over the years I did some math, well a lot of math and this is
> what I come up with:
>
> Trying to keep everything constant: Drag, HP, Rear Gear, Tire size,
Optimum
> Gear Ratios, No Overdrives, Shift Points, Polar Moments of Inertia, etc.,
> this is what I found.
>
> 6-speed transmission gave me the fastest speed at the end of 5 Miles.
> 5-speed was .1 MPH slower.
> 4-speed was .2 MPH slower.
> 3-speed was .7 MPH slower - try getting optimum ratios for a 3-speed.
> 2-speed was 1.2 MPH slower.
> Powerglide w/ no torque converter was 2.4 MPH slower.
> T-400 w/ no torque converter was 4.7 MPH slower.
> T-400 with torque converter was 11.7 MPH slower.
> Don't have any info on a Lenco, but suspect it's similar to the T-400.
>
> Probably not the big numbers some were looking for but given different
> vehicles, HP, Traction, the fact that I was keeping many things constant,
> and this is math only, I think the results may actually be greater. Also
the
> difference in MPH between the 6-speed and the 4-speed may not have you
> rushing out to plop down the extra three, four or five grand for one
either.
> But if you want the ultimate!
>
> John Beckett, LSR #79, E/FCC
>
>
> ----- Original Message -----
> From: "dahlgren" <dahlgren@uconect.net>
> To: "The Butters Family" <bbutters@dmi.net>
> Cc: <Land-speed@autox.team.net>
> Sent: Wednesday, August 30, 2000 8:43 AM
> Subject: Re: Bonneville Transmissions
>
>
> > I don't mean to flame or harass on this issue but I find it very
> > interesting and a core subject to the sport of land speed racing. So
> > please don't take any of it the wrong way hopefully...This is long and
> > may beg for the 'delete' key so be warned..
> >
> > if a theory is correct it works no matter what the variables are.. So i
> > did go out and put my car in second ..drove 100 feet a valid distance in
> > my mind .. with the engine floored it was much slower than using 1'st
> > and second....car weighs 2500 lbs has about 150 hp and 170 ft lbs
> > torque..traction was not a problem in either case
> > I think your theory if it is going to work has to have unlimited
> > distance.. Acceleration does matter because if you are going faster
> > sooner then you have more distance left to achieve the peak velocity. By
> > the way the long course in my mind is only 4 miles long in the first
> > place because the only way to reach the highest AVERAGE speed over a
> > mile is to have the entry and exit speeds be as fast as the car will go.
> > A good example would be a car that enters the final mile at 250 and
> > exits at 275.. if I put more gear in the car it will accelerate to a
> > greater speed at the entrance because you have the is gearing advantage
> > for the whole 4 mile previous and will only go slightly slower at the
> > exit speed..I have been doing this since 1991 at bonneville and it works
> > every time.. the downside is 1 it is harder on the engine(more rpm) to a
> > small degree and 2 the driver hates the zero G input to the car and
> > complains about it seeming to float.. The downside to not using a
> > transmission are 1 it wastes valuable real estate waiting for the car to
> > get up to speed. 2 if there is any problem with the run there is not
> > enough distance to ever recover 3 it is very very hard on the bearings
> > to lug the engine down to a very low rpm and apply full load. it is also
> > very hard on the pistons for several reasons the most being if you have
> > a carb the main jets have no picked up yet and the engine will be very
> > lean and the high egts will hurt the engine (burned piston)..If you have
> > mechanical injection the engine will surely be fat and take a while to
> > clear out if it does not wash the rings out..If you have EFI and it is
> > tuned right the air fuel ratio will be good but now you are making even
> > more power on the slow turning crank and beating the bearings to death..
> > I really hate to blow my own horn.. but i have been racing
> > professionally since around 1975 24 hrs daytona Nascar winston cup
> > nascar Modified Bush cars..Drag races.. fastest car shootouts..won
> > zillions of races / championships / manufacturer titles / pole
> > positions..etc To be real candid if you went to every event held at
> > bonneville and set a record at every one i suspect you have still not
> > won enough....I am semi retired now as the pressure of all that every
> > day was too much for me but did learn so many tough lessons that they
> > are not forgotten.. I still consult, manufacture some parts that always
> > seem to end up on winning cars and travel around doing tune up work and
> > new product design for other companies. Do yourself a favor just for
> > laughs. Try it my way and see if you car is faster...what is to hurt by
> > running a different gear ratio for one pass or running the engine up in
> > rpm and keeping it in the power peak for a full pass???? If it is so
> > fragile that it can't stand the rpm then fix it...
> > At what RPM does your car make peak power?? peak torque??? In all my
> > years i have never seen a car that did not go faster with more torque at
> > the rear wheels, though i have seen many cars with suspension that was
> > incapable of transmitting the power(fixable) and have seen drivers that
> > would not drive and apply the torque sensibly(replaceable) and have seen
> > tires that would not hook up(selected wrong) and have seen cars that
> > were hopelessly constructed wrong(disposable).
> >
> > If you know the HP and torque #'s for your engine and the appropriate
> > rpm,very valuable info, and your car is still accelerating beyond the
> > last measured mile I am willing to bet you that if you work on the
> > gearing and shift points the car will go faster than it does now. will
> > the peak speed be greater?? maybe , maybe not.. is there a record for
> > exit speed?? not that i am aware of.. to attain peak speed in most cases
> > the car has to run about 5 to 8% beyond the rpm for peak power through
> > the entire timed distance and not be able to go very much faster at the
> > 5 than it does at the 4 for the highest average speed. you should be
> > right at the wall when you have no more power left to overcome the aero
> > drag and rolling resistance with the engine is up to speed... If the car
> > is not getting light then adding weight is worse than adding more tire
> > to get the bite to this this because the rolling penalties are less than
> > the inertia problems associated with the weight. You should be racing
> > the lightest car that does not want to fly.. I would think that anything
> > in the /CC classes can have any suspension they want. There are many
> > designs that will apply torque very softly to the tires and allow them
> > to hook up with small g loadings and do not rely on a great deal of
> > weight transfer. If spinning the tires is a problem i would look at the
> > suspension and tires way before taking power out of the car by running
> > the engine in high gear only.......
> >
> > my opinion for what it is worth or not...but a real good topic to kick
> > around..
> > Dahlgren
>
>
>
>
>
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