Help!! What oil and pistons for Tamiya dampers on Procat?

[kaszal]

What do these spring measurements mean?

[QuackingPlums]

I would hazard a guess that 045 refers to wire gauge (0.045") but not sure about the others. We'd need the length, diameter and pitch to get some made?

[Jay Dub]

I believe it is .045 inch wire, by the # of coils, and the length in inches.

[kaszal]

Thanks

AE springs seem a good match for the front e.g. AE blue 1.66" long / rate 4.2 and AE silver 1.3" long / rate 3.85

Are shorter springs more progressive?

[Jay Dub]

Generally speaking yes. But there is something to do with shock angle, regarding suspension progression. -Jeff

[kaszal]

Thanks for your comments. Think I got the dampers nearly sorted...

Front: 2 hole piston 1mm dia, 30wt oil, AE blue springs 4.2 rate, short Schumacher ball cups

Rear: 2 hole piston 1.3mm dia, 30wt oil, Losi yellow springs 2.0 rate

Got spacers on shock shafts to limit downtravel and both roll bars are back on. Still seems a bit hard but I'm hoping it will handle Stotfold better (astro turf track with jumps) and won't bottom out or roll too much.

Here's a video of me doing a "drop test" whatever value that is, have a look...

http://www.youtube.com/watch?v=DFlLTH4p13o

[Jay Dub]

Looks like a good starting point. However, it does look like your static damping might be a hair thick. Let us know how it works. -Jeff

[kaszal]

Thanks Jeff, is it the front that you think is a bit thick? I was thinking of opening up the pistons holes a little to 1.1mm dia. Ground clearance on these CATs isn't great so it's a bit of a compromise to get it to handle well but also cope with the bumps and jumps.

Any comments welcome, Luke

[Jay Dub]

Yeah, the front looked a little thick. This depends greatly on how bumpy the track is however. I think opening the holes a little is good, or even going to the next piston hole set (whatever that is), and trying 35 wt oil. If the track you are running on is smooth with high traction, what you have there might be perfect. If it is rough, or low traction then it may give you less steering than you might like. Not quite sure what you mean about ground clearance though, as the Schumachers have more than enough down travel (droop), and "ground clearance" should be a matter of where you set the ride height. -Jeff

[kaszal]

Thanks Jeff, I'll drill them out to 1.1mm and try 35wt. The droop is about 33mm and the ride height about 23mm, is that comparable with other CATs or buggies? Don't forget I'm not using the original dampers or springs.

I also measured the rear:front weight ratio at 58:42 so is that a little light up front?