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  #1  
Old 4th February 2011, 01:45 PM
baz-r baz-r is offline
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Default shocking question?

i have a bit of a Q to do with shocks and why we need to have this 1" extension instead of making the hole shock longer?

so 13"-9" + 1 would be replaced with 14"-10 (14"-9.5" is a std size)
this would open up the list of sutable makes and 4x gaz inc springs could be got for 247 thats 110 less

cant see any problems with the rear its the front as we would be looking at an extra half inch stroke witch could be a problem for the draglink/top ball joint

a half inch spacer at the bump stop should sort it?
what we think
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  #2  
Old 4th February 2011, 01:59 PM
fabbyglass
 
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Beats me why matey maybe just a marketing thing to cream more quids out of you...no doubt somebody will know why
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  #3  
Old 4th February 2011, 03:25 PM
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Bonzo Bonzo is offline
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Hi Barry

This is how the extensions came about came about ( This is to the best of my knowledge )

After the book was written & Roadster Number 1 had been on some real life roads, it was found that the dampers tended to reach full extension on bumpy surfaces .... Just guessing here " Full Droop !!?? ".
Sorry, clueless when it comes to suspension terminology

Chris decided the best way to counter this problem would be to add a 1" extension to the top of the damper .... This way, the original active part of the damper would remain unchanged.

Purely guessing here, I would imagine that if longer dampers were fitted, the springs lengths & rates would need to be changed to allow for the longer active part of the damper.

Chris felt that it would be unfair to expect the average builder to start messing about with the suspension geometry .... So much easier to use an " Out of the box solution ".

The way I look at it is, both Dampertec & Protec supply the roadster shocks with a 1" extension to cater for the Roadster.
I am sure that if there was a better solution available, either company would advise accoringly

Been fabricating & working on motors for year's & I will be the 1st one to admit .... I know diddly squat when it comes to suspension design & geometry

Hopefully there is some logic in there somewhere !!
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  #4  
Old 4th February 2011, 05:11 PM
baz-r baz-r is offline
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well the load will not have changed so spring rate would be the same (seems people are useing diffrent rates any way.

i did ask the guy at dampertech over the phone and he could not tell me why we need the extension instead of a longer unit. he seemed to think it was due a clearence issue from frame and bodywork.

if we where to look at what the diffrence would be between a std fitment shock with the extension and one without but longer (next size up) what would we get.
eye to eye length would be the same open.
eye to eye length would be half inch shorter (bump stop could be ajusted possibly with a simple spacer)
extra half inch stroke at shock (could be an issue for movemet at drag link).
spring seats can be ajusted so if we use the same length spring we could ajust up the seat but this might reduce the amount of running ajustment or run out of ajustment so the other option would be to use a longer spring.

what we realy need to do is get mr gibbs himself to tel us why we have the extension in the first place and why we dont just use a longer unit
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  #5  
Old 4th February 2011, 05:19 PM
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alga alga is offline
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The way I see it 14"-9.5" with the springs a touch harder would be equivalent.
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  #6  
Old 4th February 2011, 05:29 PM
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Bonzo Bonzo is offline
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Quote:
Originally Posted by baz-r View Post

what we realy need to do is get mr gibbs himself to tel us why we have the extension in the first place and why we dont just use a longer unit.
Here you go Barry Straight from the horses mouth

Item 10 Here

I have spoken to Chris in great detail at some of the shows .... Bless his cotton socks, spent a lot of time trying to cram that info into my thick skull
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  #7  
Old 4th February 2011, 05:36 PM
fabbyglass
 
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I would use 14" open length dampers then as there is a cock up somewhere.......
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  #8  
Old 4th February 2011, 08:04 PM
baz-r baz-r is offline
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here is a thort if orignaly the car was designed to run 13-9 no extension
then a 14-9.5 would still be in scope of the drag link as the orignal 13-9 would be half inch shorter fully closed position.

any one have a pic of the 1"extension type fitted with the ride hight set idealy with engine like a pinto or zetec fitted so we have an idea how far up the spring seats are set
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  #9  
Old 4th February 2011, 08:31 PM
fabbyglass
 
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If using a shock with an inch extension in the body fits then a 14" shock will fit no problem. I don't see any reason to use the more expensive option.
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  #10  
Old 4th February 2011, 09:15 PM
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Talonmotorsport Talonmotorsport is offline
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Does it not stand to reason that if the book says to use 'x' then every body goes and buys 'x' so when people do group buys and starting selling parts they just read the book and supply 'x' ?
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