The Rodding Roundtable
Motorhead Message Central => Rodder's Roundtable => Topic started by: Old Blue on May 07, 2010, 10:25:19 PM
Is there a way to measure shocks to get it right ? I want to order some Pro shocks for the front and back of the roadster. Speedway has them in different lengths.
I know that because of my front end design,the 4" dropped axle etc I will need a pretty short shock. The rears will be longer.
What are the guidelines regarding shock length,travel etc. ? I am doing a totally custom set-up, nothing is off the shelf except the Magnum axle so I need to know how to determine shock length and mounting angle too.
Here's some info on Pro Shocks:
Pro Shocks have been around for a long time. They advertised in the old Rodders Digest Magazines way back when.
http://www.proshocks.com/aboutus.htm
They make all kinds of shocks. Speedway sells these.
http://www.speedwaymotors.com/Pro-St...hocks,870.html
Their shock chart.
https://www.speedwaymotors.com/image...t-582SM300.gif
Larry.
determine how much travel your suspension needs. Usually a shock should have 2/3 upward travel and 1/3 down. when you have calculated that then add 1/2" extra in the up position so you can't bottom out the shock.use some sort of upward travel limiter other than the shock ,again to avoid bottoming out the shock. that should do it.
Generally shocks should be within 15 degrees of vertical to be most effective.
Quote from: "enjenjo"Generally shocks should be within 15 degrees of vertical to be most effective.
I've heard that before. What is the reason?
Is there a cutaway drawing anywhere?
Quote from: "Harry"Quote from: "enjenjo"Generally shocks should be within 15 degrees of vertical to be most effective.
I've heard that before. What is the reason?
Is there a cutaway drawing anywhere?
I better clarify this. The shock actually should be within 15 degrees to perpendicular the direction of the load. In some cases, with a pushrod suspension, that would have the shock mounted horizontal.
If the shock is mounted at 90 degrees to the load, it is most effective. This , in most cases is vertical from both the front and side view. in this position it has no effect on axle wrap, or side sway. Most front shocks are mounted this way, as the nature of the suspension, this is the only control needed. On most leaf spring suspensions the shock are angled a bit front to rear to help resist axle wrap under acceleration and braking, since these setups are not prone to side sway. On most rear control arm suspensions, three and four link, they are angled in to resist side sway. If angled more than 15 degrees, the effectiveness of the shock drop off quickly, as the shock is then mounted on the hypotenuse of a right triangle, and moves less for each inch of suspension travel.15 degrees is not too much. As you get more angle, at 90 degrees to the load, the shock would have no effect at all because it would not compress at all.