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Re: Rubber vs. Poly

To: <BrYarboro@aol.com>, <spitfires@autox.team.net>
Subject: Re: Rubber vs. Poly
From: "Nolan Penney" <npenney@mde.state.md.us>
Date: Wed, 23 May 2001 07:01:16 -0400
I think the ride degradation of switching from rubber to poly is being 
overblown a bit.  A number of my vehicles (motorcycles) have had solid metal 
bushings, and the ride was still capable of being soft and supple.  Of course 
the use of metal bushings made shock (damper) setting and spring selection more 
critical then rubber bushings would have.  

The assumption that poly is stiffer then rubber is not correct.  Both can be 
formulated to various degrees of hardness, with a great range.  While in the US 
poly is typically formed harder then rubber, this appears to not be the case in 
Europe.  Buyer beware.

As for the braided steel brake lines, in my very limited experience it made a 
significant change over the new oem type hose.  This has been described in many 
articles written on the subject by sources I respect; Grassroots Motorsports, 
etc.  In the case of my braided steel hoses, the external braiding is tight to 
the hose, hopefully aiding the internal strands to prevent the hose from 
stretching.  At least I like to think that. :-)

I would not recommend slotted or drilled rotors for street driving.  The small 
theoretical gain for spirited street driving is far more offset by the 
headaches slotting or drilling causes.  Ie increased warpage, cracking, chatter 
and such.  You would be far better off to simply buy very good brake pads from 
companies like Porterfield or Carbotech or such.  I personally find Ferodo very 
good for spirited street driving, and they are quite affordable.

You can do a dandy job of getting the front end toe set with two sewing pins 
and a tape measure.  Simply poke a pin in each tire in the tread at the rear 
(3:00 position looking at the left side tire).  Measure the distance between 
the pins.  Roll the car forward one half tire revolution so the pins are at the 
front.  Measure again.  The difference is your toe.  Adjust to specs.  Yes, I 
know the engine is in the way, but you can work with the pins a bit below the 
engine.  You could even make a stick with two risers to reach up to the pins 
from underneath.  This works quite well.  

To reduce the amount of adjusting required, carefully remove and measure the 
old tie rod end, and install the new one to the same position.  Ie distance 
from the end of the sleeve to the center of the pin.

>>> <BrYarboro@aol.com> 05/22 5:46 PM >>>

Hi Y'all
If there's any further input from the list about rubber & poly, let me know.

Are slotted and drilled rotors worth the extra bucks for "spirited" street 
driving?

Same thing for regular vs. braided brake hoses, worth the extra $?

When I replace the rack any tips re: aligning the wheels after attaching the 
tie rod ends?

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