In a message dated 3/12/99 5:27:06 PM Eastern Standard Time,
gpetrola@prairienet.org writes:
> All this drivel about "GO"... With a full head of steam.
> How you gonna make thi beast heel? Or ar you gonna adopt Bugatti's
> philosphy: "I build my cars to go... Not to stop"?
>
> Heading for turn #1 at Elkhart, you'll probably have to be on the
> binders just after you pass the timing tower:)
>
> Whoa, hoss... Whoa! ....WHOA when I say "Whoa"!!!!!!!
Greg,
Neigh, neigh, my friend, stopping will NOT be a problem with this car!
First of all, it is not being built for use on a race track. If it were, the
design goals would be drastically different, and brake upgrades would be near
the top of the list. On a road race course, brake improvements are often worth
as much as horsepower improvements.
Secondly, let me ask you a question: are the brakes on your car good enough to
stop you safely at ANY legal and reasonable speed? If not, get your car off
the road, and get it off NOW - you have no business driving it and risking the
lives of others! If the brake are adequate, why would they need to be
upgraded should you decide to increase your power? Does stopping from 70 MPH
with 320 HP take better brakes than stopping the same car from 70 MPH with
only 104 HP?
Stopping distances are a function of speed, weight, and frictional forces --
horsepower does not enter into the equation. I know, I know, you're going to
say "that's true, but speed is a function of horsepower," to which I say
RUBBISH! On your way to work in the morning, look around you and see how many
cars are being driven at speeds ranging from 90 to 140 mph. If power were the
determining factor, they all would be, because just about every car on the
road has enough power to drive somewhere in this speed range.
Common sense, responsibility, and fear - not necessarily in that order - are
the primary factors in determining speed. My stock TR6 is perfectly capable
of driving through a school zone at 100 mph, but I won't drive at those speeds
in a school zone for two reasons: it's illegal, and most importantly, it's
dangerous. At any speed much above 15 mph or so, the brakes on NO car are
good enough to stop in time to keep from hitting a kid that runs out into the
street. Even if the brakes were good enough, driver reaction times aren't. 15
mph is the legal speed limit, and a reasonably safe speed limit, and I observe
it religiously (to be perfectly safe, the speed limit would have to around 1
mph or less).
When I leave my driveway, I can easily reach 60 mph with my stock TR6 before I
reach the end of the street, but I back off the go-pedal when I reach 30,
because that is the maximum safe speed for that street, and because I have to
stop at the end of the street. At 60, I wouldn't be able to stop in safely in
the distance remaining to the cross street. With the V8, I will probably be
able to reach 100, but I'll still back off at 30, for the same reasons.
Naturally, I'll hit 30 much sooner with the V8, and I'll grin a lot more doing
it, but I'll limit my speed to 30 just the same. And I'll still drive 15 mph
through a school zone.
All of the above notwithstanding, I have made major improvements to my brakes.
In the rear, I have changed the 9 inch drums with 1 3/4 inch shoes to 11 inch
drums with 2 inch shoes. In front, I have replaced the two-pot calipers with
four-pot calipers, and I will use high performance brake pads. The fronts
still won't have the stopping power of the rears, so I am adding a
proportioning valve to equalize the brakes, front to rear. (without the
proportioning valve, the rear brakes will lock up while the front brakes have
yet to reach their maximum braking force) Very shortly after the car's initial
completion, a major update to the front brakes will be added, bringing their
performance up to the level of the rear, so I can do away with the
proportioning valve. (with more powerful front brakes, they will lock up
before the rears do, eliminating the nasty business of having the rear end
swap places with the front - very disconcerning in a panic stop!) The only
reason I don't do it now is money. If it were a critical safety item, I would
just delay completion till I could afford the upgrade, but it's not.
Inadequate braking is myth number four of the top ten reasons given against
swapping in a more powerful engine. For the other ten reasons, go to:
http://members.aol.com/danmas/bottom10.htm
(yes, I know, 1 plus 10 is not 10, but the top ten list has a bonus reason
#11)
Dan Masters,
Alcoa, TN
'71 TR6---------3000mile/year driver, fully restored
'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
http://members.aol.com/danmas/
'74 MGBGT---3000mile/year driver, original condition - slated for a V8 soon
'68 MGBGT---organ donor for the '74
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