[E-Type] Larger Series I Brake Calipers

E-Type
1

OK Listers

Here is a question for you. There has been discussion about larger caliper for
the Series I E types. Everyone has been talking about enlarging both the front
and rear calipers and the effect on the master cylinders travel. Since the
front wheels/brakes do the majority of the work what would happen if you just
go with enlarged front calipers???

Cheers
Bob

2

My bet is the front would stop first.

Mike Moore
63 OTS WIP

3

Given that under light braking the braking force is going to be around
50/50, but under heavy braking it will be more like 70/30 or 80/20 then
there isn’t a lot of value upgrading the rears imho, with two caveats,
more brakes is almost always a good thing so if it isn’t expensive then
go for it, secondly the inboard brake system of IRS jags does lead to
heating of the diff seals more than an outboard rotor setup does - this
means there can be value in going to ventilated rotors (a la Gran
Turismo (US) and AP (UK)), you may need to change calipers with the
rotor change (I’m not familiar enough with their etype kits)

John> Date: Sun, 14 Mar 1999 20:18:11 EST

From: XKEJAG64@aol.com
Subject: [E-Type] Larger Series I Brake Calipers

OK Listers

Here is a question for you. There has been discussion about larger caliper for
the Series I E types. Everyone has been talking about enlarging both the front
and rear calipers and the effect on the master cylinders travel. Since the
front wheels/brakes do the majority of the work what would happen if you just
go with enlarged front calipers???

Cheers
Bob

–
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be considered flaws or defects.

4

In a message dated 3/15/99 6:35:26 PM Eastern Standard Time,
john.littler@ibm.net writes:

<< Given that under light braking the braking force is going to be around
50/50, but under heavy braking it will be more like 70/30 or 80/20 then
there isn’t a lot of value upgrading the rears imho, with two caveats,
more brakes is almost always a good thing so if it isn’t expensive then
go for it, secondly the inboard brake system of IRS jags does lead to
heating of the diff seals more than an outboard rotor setup does - this
means there can be value in going to ventilated rotors (a la Gran
Turismo (US) and AP (UK)), you may need to change calipers with the
rotor change (I’m not familiar enough with their etype kits) >>

While the vertical force on the front and rear tires varies with the
deceleration, the braking force applied to the wheels is actually fixed. It’s
determined by the dimensions of the wheel cylinder diameters as well as the
working radii of the calipers. On a '65 E-type like mine, these dimensions
result in a braking force distribution of about 61.4 percent front and 38.6
percent rear.

With modern sticky tires, an E-type could probably benefit from more like 70
percent front brake bias, so adding rear braking force will probably not do
very much good.

Csaba Csere