Though at times it is a pain in the neck to get operating properly (or at
all) the O.D. gives a BIG advantage in that you can have a selection of
gears (make that 2) for almost any corner. Getting the proper gear for the
individual corner will give a lot of lap time improvment in a hurry is you
can drive the beast. The twenty five pounds and the little friction losses
do add up but putting the power down by having the correct gear will more
than ,make up for it in most cases.
----- Original Message -----
From: <Gt6steve@aol.com>
To: <RodsINTOMG@aol.com>
Cc: <FOT@autox.team.net>
Sent: Wednesday, January 26, 2000 3:33 PM
Subject: Re: Racing with overdrives
> In a message dated 1/24/00 7:19:51 PM Pacific Standard Time, RodsINTOMG
> writes:
>
> << >>
> Steve,
>
> I'm curious. I can't guess why you would want to race vintage with an
> overdrive gearbox. First, they are about 25 lbs heaver than a standard
> gearbox (at least in the MGB). Do you seriously run out of gears on the
race
> tracks that you race? Do you get up into the dangerously high RPMs like
> 6,500 or 7,000 or more on the straights of the tracks that you frequently
> race?
>
>
> I have an MGB with and early standard gearbox converted to close ratio
with
> an MGA twin cam gearset. I run a 3.9 rearend on long tracks like
Thunderhill
> and either the 3.9 or the 4.3 on tracks like Sears Point with the 4.3 on
> tracks like Laguna Seca.
>
> I know that the MG car company ran very tall gears and perhaps an
overdrive
> in the early '60s at places like LeMans with the long 2 mile plus
straights.
> But vintage, where do you need it?
>
> It seems to me if you have your car camed correctly you should make most
of
> your power at the top of the RPM band (say 6,000 to 7,000) and thats where
I
> would want to be at the end of my longest straight in top gear. Simply
> adjust the final drive to do it.
>
> I'd like to hear your thoughts and those of anyone on the list on this
> subject.
> >>
> Hi Rod, Sorry it's taken me so long to respond.
> My GT6 is running a 3.89 rear which works out about perfect for most of
the
> western tracks at the end of the straightaway as you said. I'd like to be
> running a 4.11 to launch out of the tight twisties a little better. Vegas
> comes to mind as a 4.11 track. My thought was to exploit the OD as a way
to
> legally have a five speed to accomplish this. That's my official story.
> The truth?? A friend just bought a five speed cheater box for his GT6 and
> it's galling the HELL out of me to think he has an advantage.:-}}
> Thanx for your observations and take that flamesuit off. Bye, Steve
>
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