I need to get a set of rear shocks for my coupe and am not sure what to get, the shocks that came in it were a standard part I believe and were bottoming out. The shocks I have now are out of a hilux and are really a bit short as you have to load the suspension to install them and the have also failed. Is there a particular shock that commonly used for a lowered coupe?

I have search the net but only seem to come up with standard length replacements.

QA1 has a full range of lengths and compression.

http://www.summitracing.com/?gclid=CKKclf2piMYCFVKIfgodKR8ATg

Crumb, did you remove the bump stops? Because on a coupe they stop the shocks from bottoming out, so lowering usually does not require a shorter shock.

If you removed the bump stops, how will you control bottoming out? Shorter shocks won't solve that problem, but will allow the axle housing to slam against the chassis rail, or even worse, allow the tyre to contact the body.

I haven't removed the whole bump stop but from memory i cut 25-30 off. When i got it it was low enough that when the bump stop was complete the car would have 10mm of travel between the car and the stop with no one in the car, i haven't changed the ride height. I cut the stop and the shock bottomed out, replaced them with some hilux shocks unfamilia gave me and they are so short it makes the droop very limited. It is limited to the point that if you hit a big enough bump it will pick up the rear wheels slightly.

Really i'm just being lazy and hoping that someone has fitted a short shock that works rather than getting out and doing some measuring.

I have 35-40mm of travel between the bump stop and the body, How much travel do you need to have effective rear suspension?

I was not able to find a suitable QA1 shock. The stock coupe shocks have a compressed length of 260 mm (10.2 inch), and the only QA1 shocks that short are the double-eyelet type. Coupe requires a stud-type upper mount.

You could modify the body to accept bearing type upper mounts - reinforce the upper sheet metal. Then you could use QA1 coil-over shocks to make the rear suspension even firmer.

Quote:Race cars use a very small amount of travel for smooth tarmac. To help mitigate bottoming out they use very, very stiff springs. So there isn't much travel needed.

To be effectively smooth depends on the type of roads you travel. To be effective in not slamming the chassis, bump stops along with sufficient (firm) spring rate are required. Most cars have several inches compression travel.

I was OK with just 25 mm travel on my ute. But sometimes going over highway-to-bridge joints it shocked the whole car by coming up hard on the bump stops.

So lowering the coupe does not require a shorter shock -- whether lowering by reset spring, or lowering with blocks.

Removing or cutting down the bump stops will require a shorter shock. Once you cut about 1" (?) off the bump stops the standard shocks will start bottoming out.

One thing that will help when trimming the bump stop is to reshape it into a cone shape (as in the original) but a shorter cone. The shape helps progressively stop the suspension compared to just cutting it off flat.

Koni 80-2359 (or 80A-2359) is reportedly for 1200 Coupe with increased suspension compression due to bump stop modification. Pedders may have a compatible shock.

Im using old man emu part N43 sourced from ARB - also known as a hilux shock but theres probably heaps of different "hilux" shocks

using on both rally car and road car

i've always been happy with them, never done testing/maths of travel myself but never had a problem (although my mate with 1200 rally car spec'ed them up for his car so i assuming he did)

they require the bigger pin diameter bottom plates for the shock to mount to - from a bluebird or vanette. which is a bonus cause the stock little pin plates bend. it's also good to brace the area where the top pin mounts to the body as this starts to fatigue with also.

ARB OME are used for off-road racing here.

ARB Old Man Emu NitroCharger Shock N43 for FJ55 Toyota front. 295 mm compressed length which is longer than a stock Coupe shock (compressed length 260 mm).

interesting, perhaps i should do my own maths....

might need to modify the lower shock mount as per competition suspension manual