Bob, my dyno guy is a class winner in his Buick, with 350 ci, and he
used a slide rule like calculator to figure the quarter mile time with
slicks, and a good driver using the combo I have.
He said that it has proven very accurate for most of his customers, when
they do everything right.
He also mentioned that there was a rpm relationship with torque and hp,
that was the same for all cars, but I don't remember what it was. I
will have to call him back, and find out.
He wins, and does a lot of very fast cars in his shop, and is know as a
no BS guy, so I have a tendency to believe him.
I need to read and learn a lot more, before doing anything else right now.
Larry
Bob Palmer wrote:
>
> Larry,
>
> It's interesting that this kind of mis-information is so pervasive. The
> torque curve is definitely not what you want to use to pick the shift
> points, although there seems to be a fair number of people out there that
> seem to believe it. There are computer programs that will compute quarter
> mile times based on your dyno data, car weight, gears, etc. They all use the
> right physics as far as I know. However, a lot of "seat of the pants" racers
> seem to have lost the rabbit.
>
> Bob
>
> -----Original Message-----
> From: owner-tigers@autox.team.net [mailto:owner-tigers@autox.team.net]On
> Behalf Of Fraser, Ron
> Sent: Wednesday, February 21, 2001 8:18 AM
> To: tigers@autox.team.net
> Subject: RE: E-Mail me off the list
>
> Larry
> I'm not sure about the 80% part but I did see an explanation about
> shift points.
>
> You need to look at your engine's Torque Curve and you need to know
> what the RPM change is for each of your transmission gears. The idea was to
> shift at an RPM after peak torque that would bring you to that same torque
> value before peak torque. This uses the Max Torque of the engine to propel
> the car. This seems to make sense but I do not know if will get you down
> the track any faster. I have never drag raced, only short bursts on the
> street, so I'm no expert.
> Ron Fraser
>
> -----Original Message-----
> From: Larry Paulick [mailto:larry.p@erols.com]
> Sent: Wednesday, February 21, 2001 8:58 AM
> To: Bob Palmer
> Cc: cvaught@hawaii.rr.com; tigers@autox.team.net
> Subject: Re: E-Mail me off the list
>
> Bob, interesting point on the shift points. I understand having the
> revs in the sweet spot, but how did the 80% come about.
>
> If I have the stock motor and cam from the 90 5.0L, and its max hp is at
> 5200 rpm, the the shift point is 6500 rpm. That is quit a jump, and
> with stock valve train, mainly springs, I am sure that valve float would
> become a problem.
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