[TR] TR4A - Hydraulic Push Rod Advice

[Dave1massey at cs.com]

In a message dated 9/1/2011 6:30:45 PM Central Daylight Time, 
guy at genfiniti.com writes: 
> I need some advice on an annoying issue with the TR4A.
> The push-rod for the brake master is longer than the push-rod for the 
> clutch.
> As a result, the brake pedal is considerably further away from the floor 
> than
> the clutch and gas pedals, which are basically level.
> Seems like I should be able to replace the brake push-rod with a shorter
> length (to match the clutch) and be on my merry way.
> 
> However, going to shorter push-rod means a correspondently shortened 
> "stroke"
> for the brake cylinder. (Length from all-the-way out to all-the-way in, 
> will
> be less)
> So, this seems like it would have to compress more fluid per unit length, 
> thus
> making the pedal harder to push-in, but I would get more stopping power 
> per
> unit length.

You are confusing pushrod length and lever length.  A longer pushrod 
doesn't change the relationship between pedal travel and master cylinder piston 
travel.  The only thing it changes is the position of the pedal and full 
release and at full travel.  The actual stroke (full out to full in doesn't 
change and pedal pressure doesn't change.  

> 
> Out side of these items, does it matter for other reasons if I go to a 
> shorter
> push-rod for the brake cylinder?
> Has anyone had this issue?  If so, how did you solve it?

I had the same issue with the clutch master cylinder on my TR8 and I 
resolved it by installing the old pushrod and all was just fine.  And I did it 
with the master cylinder in place.

Dave