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front suspension damper bump stop

Posted: 17 Oct 2014 15:45
by Paul_TR8
I am after the dimensions of the front strut damper bump stops, I plan to make a more progressive bump stop from some we have at work from development projects. The original ones are missing from the struts I have just taken apart.
Length, outside diameter and internal diameter in mm would be great. Or even better if anyone has a spare I can measure the stiffness.
Paul

Posted: 17 Oct 2014 16:23
by REPLIC8
Hi Paul,
I've just removed the original bumpstops from my struts, one was a pile of dust but I can measure the other one. I don't think it would be any good for measuring the stiffness as it will probably crumble to bits.


Image

Andy
1981 TR7 FHC

Posted: 17 Oct 2014 17:52
by REPLIC8
Sizes are as follows

Outside diameter 54mm
Inside diameter 19mm
Height 37mm

There's also a 6mm x 6mm chamfer around the top edge.

Sorry about the blurred photo.

[img][IMG]http://i473.photobucket.com/albums/rr92/REPLIC8-2008/DSCN0573_zps24c72ca2.jpg[/img][/img]

Image

Andy
1981 TR7 FHC

Posted: 17 Oct 2014 18:10
by Paul_TR8
That's perfect I can do something with the figures

Posted: 17 Oct 2014 20:10
by moodyblue
Going by the picture and the height measurement it looks like half of the bump stop has turned to dust. I remember them being much longer with a chamfered groove around the middle.

Posted: 17 Oct 2014 21:52
by Beans
<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by REPLIC8</i>

... Sorry about the blurred photo ... <hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Indeed looks like only one half of the original bumpstop ...
Image

<center>Image
<font color="blue"><i>1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
</font id="blue"><b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="3"><font color="red">My full Blog</font id="red"></font id="size3"></b></u>[/url]</b></i></center>

Posted: 18 Oct 2014 01:17
by silverseven
is the bumpstop really necessary ???

The last time I rebuilt my frt suspension, I didn't put a bumper back and honestly can't notice any difference ......
(I think it was Woody that told me not to bother??)

Ron.
ImageImageImage

Posted: 18 Oct 2014 05:25
by Paul_TR8
Beans could you measure your bump stop for me please.


The bump stop is there to stop the impact when the suspension is subjected to a large impact. It reduces what is called crash through. It us also sometimes used to help with roll, as the car corners it will push on the bump stop.

Posted: 18 Oct 2014 05:43
by trsforever
Hi Paul, I have a brand new koni bump stop, I/D 19mm, O/D 44MM, Height 55mm. Also stops internal damage to damper on full bump.
If you want to control body roll we used to fit nylon packers to the damper shaft, choose your thickness cut a circle(bump stop dia) with a hole of shaft Dia and then cut a slot about 1.5-2.0mm smaller than shaft dia and using a pair of long nose pliers you put them in and pull them out through the coils of the spring.

Regards scott.

Posted: 18 Oct 2014 06:29
by REPLIC8
<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Beans</i>


Indeed looks like only one half of the original bumpstop ...
Image



<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">

That's interesting, what's in my picture was all there was inside the gaiter on one side, the other side was full of bits and dust. Wonder what happened to the other half? I'll be replacing these along with some new dampers as the 33 year old ones on my car had no damping properties left at all. [:)]


Image

Andy
1981 TR7 FHC

Posted: 18 Oct 2014 08:16
by busheytrader
IIRC the Triumphtune poly bump stops were roughly half the length of the originals and conical in shape. I haven't seen them since I replaced the front Spax and gaiters several years ago.

These look very close to what I remember.

http://www.rimmerbros.co.uk/Item--i-UKC6729PB


Adam



Image Image

TR7 V8 DHC Jaguar Solent Blue. 9.35cr Range Rover V8, Holley 390cfm, JWR Dual Port, 214 Cam, Lumention, Tubular Manifolds, S/S Single Pipe Exh, 3.08 Rear, 200lb Spax & PolyBushes all round, Anti- Dive, Strut-Top Roller Bearings, Capri Vented Discs & Calipers, Braided Hoses, 4 Speed Rear Cylinders, Uprated Master Cylinder & Servo, AT 14" 5 Spokes or Maestro Turbo 15" Alloys, Cruise Lights, S/S Heater Pipes, Replacement Fuel Tank. No Door Stickers. Mine since July 1986, V8 from 1991 courtesy of S&S V8 conversion kit (built not bought) and big brake kit.

Posted: 18 Oct 2014 15:00
by TR Tony
Paul - speak to Roy. Somewhere he may still have an original front bump stop that I gave him some time ago. It came off my FHC & was in very good condition at the time.

Of course Roy may have trouble finding it among all his spare parts [:D]

Tony
ImageImage
<font size="1">1981 TR7 FHC Cavalry Blue
1980 TR7V8 DHC Jaguar Regency Red - sadly sold!
1977 TR8 FHC EFI Factory development car Inca Yellow</font id="size1">

Posted: 19 Oct 2014 00:04
by moodyblue
On the left is a Superpro bump stop, which I think is standard length, and on the right is a Triumphtune bump stop, the TT is 1" shorter and harder. I remember reading that the stops come into play far too early on a factory set-up, this probably explains why they crumble to dust. I've got the Superpro fitted to my red wedge but they need a trim as it bottoms out too easily, hope I can do this in situ. On my next project I'm going to fit the short TT ones with standard height uprated TT springs which should be ok. I think they're to be fitted as in the picture with the small end facing down or it might not make any difference. I'll measure them when I remember where I stored them.

Image

Posted: 19 Oct 2014 01:50
by Hasbeen
In Oz we use the Holden Commodore, [Vauxhall in the UK], in standard height 7s like my red car, & cut the same ones down to half length for lowered cars like the 8.

They do work well, so must be close to the ideal hardness, & are very cheap in Oz. Probably cheap in the UK too.

I have never seen an original. No 7 I have owned had anything but a little dust in there, & a number of struts the dust cover was split or gone anyway, so no dust retention.

Hasbeen

Posted: 19 Oct 2014 07:48
by Beans
<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Paul_TR8</i>

Beans could you measure your bump stop for me please ...<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Not possible at the moment as I haven't got a clue where I stored it (if at all ...)
I use shortened bump-stops in my cars.
Got a set of shortened conical shaped Triumph Tune bump stops many years ago ...

Image

These will be re-used on the front suspension of my current project.
They have the following dimension;
Length ± 34,5 mm
Top diameter ø51 mm
Bottom diameter ø39 mm
Internal diameter ø19,8 mm

Currently running these SuperPro bump-stops in my DHC ...

Image

<center>Image
<font color="blue"><i>1976 TR7 FHC (needs some TLC ...)
1980 TR7 DHC (my first car, a.k.a. Kermette)
1981 TR7 FHC (Sprint engined a.k.a. 't Kreng
</font id="blue"><b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="3"><font color="red">My full Blog</font id="red"></font id="size3"></b></u>[/url]</b></i></center>