I can't take credit for some of the questions...
They were from a Engine Power tech. class in collage.
The amount of hp to turn a 350 Chevy (Yuck) without spark plugs 5000 rpm
was about 18 hp. Most of this was due to valve train springs. This was done
with a dyno by bolting two engines together. Both had straight 30 wt oil. It
was to prove that TEFLON oil additives didn't reduce hp loss the way they
claimed. There was a hp gain due to lower viscosity of the oil. This was
before Slick 50 and Slick Willy. If it took 90 hp my 2.3 Mustang with 85 hp
could not turn 7500. Most of the hp is used for accelerating from 0 to 300
rpm with cold oil. Hydrodynamics does not care what you coat the surfaces
with only the viscosity of the oil. Most of the local boys (NASCAR) use
0w -10 oil to qualify and 30w to race. And none use any oil additives ( that
they will admit). The next time you have an engine on a stand take you half
inch drill hook it up to the harmonic balancer and see if you don't get
about 3600 of that 1.5 hp drill.
Oh one more question that was on our final exam.
What is the max RPM an engine will turn ?
Doug Mallory
Charlotte NC
Where 24 gets stomped on Sunday.
From: Wright, Larry <lrw@aop.com>
To: Tigerlist * (E-mail) <tigers@autox.team.net>
Date: Thursday, October 01, 1998 4:24 PM
Subject: _More_ thinking? (plus Bonus topic)
>Lawrence R. Wright
>Purchasing Analyst
>Andrews Office Products Div. of USOP
>lrw@aop.com
>Ph. 301.386.7923 Fx. 301.386.5333
>
> Bob Palmer wrote:
>* I also found Doug's posting both thought provoking and, at
>* the same time,
>* humorous. I assume he intended it to be somewhat
>* tongue-in-cheek. In that
>* same vein, with regard to the starter motor paradox, you and
>* perhaps Doug
>* as well, may be overlooking the fact
>
>Bob, you may be overlooking the fact that I don't know what I'm talking
>about! :-)
>Jus' trying to apply a little logic to a subject in lieu of facts (I
>don't have any); Doug got me to thinking, which ain't easy.
>
>*that horsepower is equal
>* to rpm times
>* torque (divided by 5252). I would guess that a starter motor turns the
>* engine over at maybe 100 rpm. If this takes 1.5 horsepower,
>* then turning
>* the motor over at 1000 rpm takes 15 hp and at 6000 rpm takes
>* 90 hp!!
>
>So the friction changes directly proportional to rpm's? Gee knowing
>that, for _example_, air resistance increases with the square of the
>speed, I expected some more complicated answer. Hey, you sold me on the
>concept. And you just justified, in my mind, the cubic-money I spent on
>the 5-speed.
>
>* Now
>* where the hell did I put that can of Slick 50??
>*
>* Not to be taken seriously in San Diego,
>
>Another subject. Where's a good place to get an image of the sideways
>cat-head Tiger logo? I'm thinking if I blow it up and transfer it to a
>pumpkin, I'd make a neat Jack-o-lantern (I bought one of those
>micro-saws made for the purpose). Scary growling cat, plus it would be
>Tiger-related. Looking for one to download, and blow up to correct size
>on the printer.
>
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