Hi,
Does anyone happen to know how tall an unmodified front bumpstop is?
Also would be good to know the internal diameter too.
Thanks.
I've just bought a pair - the ones attached to dust boot? The bump stop itself is 35mm high from the top of the dust boot and about 72mm in total length. It looks to be 55mm in diameter
Quote from: ooch on June 15, 2020, 13:51I've just bought a pair - the ones attached to dust boot? The bump stop itself is 35mm high from the top of the dust boot and about 72mm in total length. It looks to be 55mm in diameter
Yes, thats great thanks. Very helpful.
What it the internal diameter at the top of the stop? (ie the bit that stops crap getting down the strut shaft?).
The reason I am asking is that I have bought a set of dust covers and bumpstops from a fiesta which are much cheaper. (Fiesta Mk 5 2.0 2005-2008 model).
(https://i.imgur.com/MaAYfbq.jpg)
They are about 83mm tall and 55 external diameter but are a bit looser on the shaft than ideal at about 23.5 mm on the shaft of about 20mm. Knowing that they are longer, it helps me guess how much to trim them for my lowering springs.
If the MR2 ones are a tighter fit then I need to see if I can come up with something to give a better seal.
Be careful fitting non standard bunpstops, like many cars these days they are not just a bumpstop (for saving damper on huge impacts) but actually play an active roll in spring and damping rates, changing length and hardness is not a good idea!
Quote from: Topdownman on June 15, 2020, 15:42If the MR2 ones are a tighter fit then I need to see if I can come up with something to give a better seal.
What do you mean by 'a better seal'?
Quote from: Gaz mr-s on June 16, 2020, 15:40Quote from: Topdownman on June 15, 2020, 15:42If the MR2 ones are a tighter fit then I need to see if I can come up with something to give a better seal.
What do you mean by 'a better seal'?
I mean more like the rear ones which are a tight fit on the shaft and therefore stop crap coming over the top of the gaiter. I havent got any ideas how to do this though as it would ideally be tight enough on the shaft to give a better seal but loose enough to move with the bumpstop so it didnt get left behind at the top of its travel (full compression) where it would then do no good.
Since deciding to try the cheaper stops, I have found out there is a lot more to bumpstops than I thought but having bought these, I will fit them and see how I get on. All suggestions welcome!
I don't think I know anymore than you Topdown (I'm about to post my own difficulty....) but the bumpstop should sit at the top I believe, & only come into play when the suspension reaches full compression. I've bought different bits for mine front & rear too....the prices of bits for the 2 were stupid in comparison to others. I doubt the rears will compress enough to bring the bumpstops into play, not sure about my fronts yet.
If the bumpstop is going to slide down could you try a cable tie to tighten it on.?
Hopefully this picture shows my issue.
(https://i.imgur.com/Tn5MgcR.jpg)
The rear stop grips the shaft nicely although its a different design so not sure how relevant a comparison is.
On the front one, you can see what is a 3mm gap between the stop and the shaft that I assume will let mud/water/salt etc get through the gap and that isnt good obviously so I want to do all I can to stop it getting in.
I really want to try to replicate how the oem fronts work hence wanting to find out the internal diameter.
Just knowing if the fronts are a tight fit is all I really need to know.
The new boots are plastic rather than rubber and there is only 65mm of the shaft above the top of the boot with no spring/car weight on so I guess the resistance of the boot will keep the stop near the top. Perhaps some sort of washer to sit on top would do? Not sure what I could use for that though.
Good luck with your issue!
Stock ones are a nice snug fit on shaft so like you say crud cant get in there, those baggy ones as well as being probably wrong grade/hardness/length etc are also not going to do much to protect the damper shaft seals, although it could be with the long bumps that its forced up into the underside of top spring plate and seals that way, fitting it you will soon see once car is lowered onto wheels.
Personally i would just buy the right bumps stops for the job as they are such a critical part to how the suspension works, especially on front of these cars.
Thanks for the info that they are a snug fit.
I hear what you are saying but even if I bought oem ones, there is still the question of how much to trim them down for Tein springs with a 33mm drop so wont be as toyota intended in any case.
I have tried new kybs and tein springs on the car before and found it surprisingly stiff. I dint trim the bumpstops though on that ocassion so now realise that I might have been riding on the bumpstops so do want to trim them this time.
Tein used to spec how much to cut them down when using their springs but for some unknown reason stopped doing it, many find car is too firm at front if they dont cut, i cut mine down just a bit less than the drop of the springs from what i remember, might have the info somewhere or will measure what did once i get this engine in and can get in to have a look.
I did try to look up the recommended cut. The info I could find is pretty minimal but what I did find suggested a 0.8" cut on the front (20mm?) and none on the rear.
In thinking about this today I realised that when I changed the shocks last time, I used new bumpstops from MR2Ben. I dont think he uses proper oem bumpstops but ones that fit so another reason for the car feeling stiff still, apart from the non cut stops could be that they were too firm.
I will need to give this some more thought. I have plenty of time because the supplier of the Teins I have ordered has said it will take him4-5 weeks to get them!
Looking back at my posts i cut 25mm off fronts and 20mm off rears, i dont think the rear cut is really needed as its not so active, as in there is more free travel before bumpstop starts to come into play.
If you cut them it must come of the top where it butts upto spring plates, the bottom part that touches damper casing is progressive and needs to remain that way.