Damper hat to wishbone clearance

[Redmax]

Morning. I've finally made a start on my build, what with it being Christmas and all...

My damper hat is lightly fouling the upper wishbone - am I right in thinking this is only an issue in droop and it'll be OK when it's on its wheels?

Thanks

Jason

[Westfield 129]

When the car is on the ground, and properly set up, this wont be a problem. The clearance is very tight (the thickness of a credit card, actually). Make sure that you set the ride height properly (Driver installed prior to ride height adjustment) so that the spring is not disloged when the car is lifted.

In any case, the clearance is OK once the car is road ready. Just make sure that you set the ride height with the driver in the seat so that the springs are properly seated on the dampers. When you do the initial coil over installation, tighten the collar so that the spring is fully captured and slightly compressed when the damper is fully extended. You can do this by hand prior to bolting the coil over assembly to the chassis.

And if you want something better:

You can put the rear dampers on the front (they are smaller in diameter and the hats are shaller as well) with a small diameter 300 lb/in spring (same height as the larger diameter spring that you already have) and put a new small diameter damper onthe rear that would be an inch or so longer. The small diameter damper gives lots of hat clearance for the upper arm.
I have the precise measurements for custom front and rear dampers if you are interested. The benefits are an improved ride and handling. GAZ has longer small diameter dampers for the rear of the proper length if you want to stick to the OE dampers and save a few quid. Otherwise, I recommend a custom set of Protech double adjustable damperss, mounted upside down to make the adjusters easy to reach, and to keep them from the road grime.

The longer, small diameter dampers puts the chassis back to the original setup of the early chassis, which used longer dampers and had slightly more suspension travel. You will hve to cut an opening in the rear beneath the differential and the swing tree mount.

Quick note: Don't cut the steering tie rods until you are ready to set the ride height. Set the ride height FIRST, then the tie rod length (you will have to cut the tie rods and the rod ends as well). Again, driver in the car to set the front toe (tracking) and camber prior to cutting the steering tie rods and the rod ends.

Oh, and order a new "Fat Rack" if you don't already have one from your donor car. Quicker steering ratio. Much better than the sedan ratio of the later skinny rack.

[Redmax]

Thanks W129. It's reassuring that 'they all do that', but I'd be interested in the details of your custom dampers when you get a minute please. Having a bit of experience with racing Caterham spring rates, the 350lb/in springs that come as standard sounds a bit high, so I suspect there's a better job to be done there...

Cheers

Jason

[Splat]

Five pages of thread here viewtopic.php?f=4&t=175&start=30

Save yourself some bother and skip to the bottom of page 4. There you'll find the specs of the custom Protec shocks that I spent an age ithering over. Lengths, diameters and spring rates. They work.......

Merry Building......

[Westfield 129]

I concur on the damper lengths and diameters for the Protechs.

My spring rates are a bit lower, though, as the dampers are really good, and the car is light.

My recommendation is 300 lb.in. front, and anywhere from 130~150 lb.in in the rear. Splat's number is probnably pretty close for a good two up setup. It also would be good if you install a clutch type LSD, such as a TranX or 3J.

The Protech dampers have an adjustable range for each valve set, so you can "custom valve" the dampers yourself (this is a relatively simple re positining of the valve shaft to change the indesing of the adjustment knob for a lighter or heavier rate), or you can tell the nice fellows at Protech to set the damperfs for a car that weighs about 1000 lb. (I would tell the to back off the adjusters by 1.5 or 2 turns when they are set up prior to shipping). This should give a couple of clicks of adjustment for the rebound and the compression.

I mount them upside down, adjusters on top. Much easier to set up, and the ystay a little cleaner.

Or, you can use the rear dampers up front, and new, longer GAZ dampers in the rear using the same langth open and closed as the Protechs. Same springs, too.

[Redmax]

Lovely, thanks Chaps.

[Splat]

So, the holidays are over. Did you finish the build?

[Redmax]

Not quite! I've made some reasonable progress but never seem to have the right bolts or quite the right parts, so lots of unfinished jobs... Hopefully lots of stuff I've ordered over Christmas will arrive this week and I can properly tick some jobs off!

[Westfield 129]

The fasteners are divided into both metric and fractional sizes.

The suspension is all fractional, which means that you can substitute grade 8 or AN/NAS aircraft uality or Mil Spec hardware.

The body and other fasteners are metric.

I replaced all of the metric chassis bolts (there are a few) with fractional sizes so that I could limit the number of tools that I would need to service the engine, suspension and bolted on systems.

The body fasteners (windshield and other bits) are still metric.

The metric fasteners were marked when I received my last kit.

[Elva 11]

Re the damper/ wishbone clearance.
I've just pulled the front suspension down in order to fit 'our' new bushes and Protech dampers. The original Westfield o/s front damper hat has, in 5 k miles, worn a hole 4.5 mm long through the underside of the upper wishbone tube.
The ride height was all set correctly, surprised as there should be a (very small ) clearance when running normally - maybe it's all these hump back bridges down here.
No problem to weld up but would not want the hole to open up into a split.
Might be worth checking if you have the standard set up as it's not a normally visible area.