>Subject: Re: Springs for Racing
>Sent: 10/2/98 5:40 AM
>Received: 10/2/98 12:05 PM
>From: rebean@mail.hac.com
>To: rodbean@ix.netcom.com
> jangr@email.uc.edu
> atocha@globe.com.ph
> rebean@mail.hac.com
>CC: lotus-cars@lists1.best.com
> Chapman-era@autox.team.net
>
>
> Hi Andres,
>
> I'll mail this to myself at home where I have some numbers stashed in
> notebooks. I'll answer from there.
>
> Rod
>
>
>______________________________ Reply Separator
>_________________________________
>Subject: Springs for Racing
>Author: atocha@globe.com.ph at uuencode
>Date: 10/2/98 7:16 AM
>
>
>Hello Rod and Ray,
>
>Would appreciate advice on spring rates and dimensions for my S4 (Classic)
>Elan. The two tracks we race on here have some bumpy corners, but one
>circuit is smoother than the other (I can change springs if needed). It has
>been suggested that I start with 250 lb springs in front and 150 rear. The
>250 lb springs I have have an uncompressed length of 6 inches. I was
>reading
>in an old article on Tony Thompson's car that he used this combination, but
>Tony Dron found the ride too harsh (I know TT now uses a much higher rate),
>
>I will be using Dunlop vintage race tires (450).
>
>What spring rates would you suggest? How do I calculate the point when the
>coils will bind?
>
>Many thanks, and I have learned a lot from your exchange on A-arms.
>
>Regards,
>
>Andres
>Manila
Hi Andres and Ray,
Hear is what I have in my files (all Elans are S1, S1 1/2 or S2):
Used on a slalom S2 with no flares and 6" Minilite wheels (ordered with
correct offset)):
Frt: 170-175 lb./in.
Rr: 135-145 lb./in.
This combination produced some interesting handling. It was okay except
that it kept wanting to turn over (roll). Both the owner and I almost
turned it over.
Then....
The springs were changed to:
Frt: 240 lb./in.
Rr: 200 lb./in.
Also, the fenders were flared and 8" wide cast knock-off Revolution
wheels were used. I don't know what the offset was but the flares were
pretty big and the wheels filled them. This was the car that I mentioned
where the larger diameter, longer drive pins were used for the wheels.
There was no more tendency to roll over and it won several slalom
championships.
The S1 1/2 bolt-on car came before the car above. This car had no flares
and had 6" Minilites ordered with the offset required (different frt. and
rear). These wheels were probably dimensionally close to the 6"
Minilites above but there was never any tendency for this car to roll
over. I assume this is because the spring rates were different.
Unfortunately, I don't have the figures for that one.
I know there is considerable information missing here but it's all I
have. Good luck.
Rod
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