[Land-speed] Engine Placement

[Dave Dahlgren]

Right now you are at the point where you are not fixing something that is 
broken or designed wrong and asking questions to avoid that problem. If it 
were me I would borrow a set of wheel scales and get an idea of what the 
weight distribution might be with a couple of different locations and where 
you might think the center of pressure might be as well.Avoiding the hood 
scoop would be a plus in my mind why add the drag if the weight distribution 
is not that different? Getting the center of gravity in front of the center 
of pressure with the most weight on the drive wheels would be my choice 
personally. You can have a car with 40/60 weight distribution as long as the 
center of gravity is in front of the center of  pressure..
Dave
----- Original Message ----- 
From: "Ed Weldon" <23.weldon at comcast.net>
To: "Mike Lackey" <mike_lackey at yahoo.com>; <land-speed at autox.team.net>
Sent: Sunday, January 13, 2008 2:10 AM
Subject: Re: [Land-speed] Engine Placement


> IMHO in general anything you do to help keep you going in a straight line 
> is
> the right thing to do.  This may well be contrary to what is conventional
> wisdom for cars that are built to go well around corners.  Putting weight
> forward rather than toward the center increases the polar moment of 
> inertia
> of the car which should make it harder for unbalanced aero forces to 
> rotate
> the nose into a spin.  (You know, the opposite of the trick figure skaters
> do with their arms to make themselves spin faster)  Also putting weight
> nearer the front wheel centerline will help traction for steering control.
> If this means taking weight off the rear wheels, no problem.  Add extra
> weight there.....you've got two miles to get that little GC up to speed.
> But best of all, listen to the guys who have "been there and done that".
> That's not me.....I'm an open car guy.  Frankly I doubt if you'd notice 
> the
> difference between the two options you're considering in a 135 mph gas
> coupe.  So factors other than handling may be most important.
> OK, all; the target is up.  Fire away.
> Ed Weldon
>
> ----- Original Message ----- 
> From: "Mike Lackey" <mike_lackey at yahoo.com>
> To: <land-speed at autox.team.net>
> Sent: Saturday, January 12, 2008 9:52 PM
> Subject: [Land-speed] Engine Placement
>
>
>> So, I've tried setting my engine in place to get an idea of where I want
> to put it.  As a reminder, this is an '86 Toyota Corolla that's getting a
> Yamaha R1 engine to race as an I/GC (Note: this means I've got a 
> significant
> loss of weight over the front wheels already).
>> I can either put the engine forward and low in the car, or close to the
> firewall and up a couple inches.  Putting it near the back would require a
> hood scoop, while the forward position might not need one.  I've got some
> ideas on which I'd prefer, but as I'm new at land speed racing, I wanted 
> to
> get a second opinion.  Any tips would be appreciated.  .......Thanks, Mike
> _______________________________________________