bump stop lenght

[FEDUP]

Hello.
What sould the lenght of rear bump stop be for 1969 +2s i brought two progresive bump stops from p mattys a few years ago these are approx 6inches long and tapered from 1.5 dia to aprox 2.5 dia , I have adjustable spring perches and koni adjustable inserts with up rated springs of 120lbs standard lenght.Now the car is nearly finshed i noticed when fitting the rear exhaust silencer the rear suspension as only a small movement before it hits the bump stop .
Also with this type of bump stop dose it matter which way round it fits ie large dia to lotocone small diameter to shock.Also when i fitted the koni inserts the lenght of insert was shorter then the tube is it normal to place packer in bottom of tube as this is what i did which at the time seemed logical.
would appreciate any advice .
regards ian

[tcsoar]

Hi,

Dont now about your bumpstops, but you mentioned putting a packer in the tube as your Konis are slighlty shorter than the tube. I also had this with the Gaz inserts that I installed, Gaz actually supplied the spacer.

Chris.

[miked]

Ian,

If you search about bump stops (rubber spring - Eon rings a bell) you will find Rohan talking about this and as I recall he says that the old rubber one is best with a spacer. I believe the Plus two were fitted with an alloy collar to limit travel. I have couple of sets in the garage that I have salvage over the years from struts fitted to plus two's. I was not aware what the crack was until I read what Rohan said about the rubber springs being really good with the extra 20 odd mm of alloy.

I have some of the Pual Matty ice cream cone shape ones on my S4 and have the wide part to the lotocone. They feel very soft to me especailly for the heavier plus two (if they are all the same ones). I have litlte or no experience at this but I suppose it matters whether you are going to drive it hard on track and get it over onto the stops. I know mine has very little space left but they do squash up easily. Subject on its own!

Re; short inserts, you are aware it is short stroke to limit drive train angle on droop.


That all I can recall.

Mike

[rgh0]

The orginal bump stop used on the Plus 2 and Elan was an "Aeon type 505" rubber spring that was around 80 to 90 mm long. Unfortunately I dont have a new one to measure up and the ones on my cars are somewhat distorted by use so the length dimension is a best guess.

A company called Timbren in Canada now appears to be the maker of Aeon rubber springs from a web search but it does not list the type 505 rubber spring on its web site . Dont know if any of the usual suppliers still have the orignal spring or equivalent as I have not bought any new ones for a lot of years. These springs are a crucial part of the how the rear suspension works and need to be used - they are much more than just bump stops

Later plus 2 also had an alloy spacer of around 20mm thickness between the rubber spring and the top of the strut. I have attached a photo below. I included a similar thickness spacer on my Elan which I found greately improved the somewhat vicious roll oversteer you can encounter on the track with modern sticky tyres. The plus 2 does not have the same handling characterisitic due to its wider track and longer wheel base and I presume the spacer was added to help prevent bottoming out when heavily loaded


cheers
Rohan

[FEDUP]

hi
Thanks for the information i have also spoke to roy at p mattys and he advised to cut the ones they supplied down to approx 3"I then spoke to stuart at TTR, the poly bump stops the supply are approx 2" long ?.
I may still have the oringinal bump stops stored away some were so i will see what condition they are in, then make two off alloy spacer as drawing supplied by rohan .Hopefully then i will have the correct instalation .
Thanks again.
ian

[FEDUP]

hello again just thought can"t use the oringal type due to sping dia the car is set with 2.250 springs so at the moment its either TTR poly type or cutting down the univsal type from mattys .
ian