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rcjperformance
03-04-2012, 06:14 PM
Does anyone know of somewhere i can find a table or chart to show what valving number = what force/ shaft speed?

eg a 5 valve afco = 200Lbs force at 5 in/s compression and 200lbs of force at x in/s rebound?

is there any standard?

Egoracing
03-04-2012, 06:20 PM
Does anyone know of somewhere i can find a table or chart to show what valving number = what force/ shaft speed?

eg a 5 valve afco = 200Lbs force at 5 in/s compression and 200lbs of force at x in/s rebound?

is there any standard?

Best info you can get is to put your shocks on a dyno. A 5 from one company may not read what a 5 from another company reads.

rcjperformance
03-04-2012, 07:55 PM
I have the dyno, was just trying to find some number to compare against, have already found the differences between companies, and also differences between shocks of the same brand, all be the differences minor.

I have for the old carrera shocks these numbers 1 = 11, 2 = 135, 3 = 175, 4 = 220, 5 = 265, 6 = 320, 7 = 390, 8 = 475, 9 = 600, 10 = 750, 11 = 900

But without having a speed for these in rebound and compression i am only guessing

Ideally i would like what afco or pro use for their valving

powerslide
03-05-2012, 02:58 PM
i tried to find exactly what you are looking for without any success. I was helping a guy who had a afco sheet for a summer but i havent ever been able to find one. I never made any calls to companies but surely if you did that they could help you out.

MasterSbilt_Racer
03-05-2012, 04:04 PM
The shaft speeds seem to vary by application, brand, and the guy valving the shock. If you have a dyno, you can compare anything you want. Make your own table.

A RF shock on a Cup car at Daytona is going to see shaft speeds off the chart compared to one on an 86 Monte Carlo at Albany GA Motor Speedway.

MasterSbilt_Racer
03-05-2012, 04:09 PM
Keep in mind that Brand X and Brand Y, while the same at 4 in/sec, could be different at 6 in/sec.

JR. MECHANIC
03-05-2012, 11:33 PM
Call AFCO, explain what you're doing and they'll probably help ya out.

jason29a
03-09-2012, 09:04 AM
I have sheets from... Qa1, Pro, Penski, and Advanced that decribe what the valving is @ 1 in, 3in, and 6in.... They tell you for example what a 4 valve is at though those inch numbers. But as it has been stated it is merly a referrence. The different companies vary quite a bit. And they dont get into if the shock is linear, progressive, digressive, or a combo of the two. Or if the shock is big nose or small nose, meaning how quickly or slow the inch pounds increase.

So basicly there probably more hurtful than helpful. The best bet is dyno what you have, figure out what you got. And then from racing and testing, decide where you want to be. If you seek help from a shock "specialist". chose wisely, or your pocket book will be more affected than your racecar.

joedoozer
03-09-2012, 10:42 AM
Keep in mind that Brand X and Brand Y, while the same at 4 in/sec, could be different at 6 in/sec.

If that is the case is there any accuracy to trending a shock on a simple tester? Hanging a set weight and timing the rate of compression or extension.

MasterSbilt_Racer
03-09-2012, 12:21 PM
If that is the case is there any accuracy to trending a shock on a simple tester? Hanging a set weight and timing the rate of compression or extension.

I don't really think so. You will be making a comparison at very slow shaft speeds. You won't really be learning anything about the shock's behavior on the race track.

To really know what is going on, you need to know the shock's force at a number of shaft speeds that are relative to your application. You need to know the hysteresis or how it behaves when the shaft changes direction. You need to know high and low frequency response.

As Jason29A explained, we really know very little about our shocks unless we dyno them ourselves. Then we are still limited by how sophisticated the equipment is and what information we choose to analyze. We can have two sets with the same force at 6 in/sec and they can be totally different.

joedoozer
03-09-2012, 12:37 PM
Not looking to learn anything on the track. I want to trend the shock so I know when the performance is starting to drop off and its time for a rebuild.

MasterSbilt_Racer
03-09-2012, 01:23 PM
Not looking to learn anything on the track. I want to trend the shock so I know when the performance is starting to drop off and its time for a rebuild.

Ah, Ok. That might work for you on a twin tube shock.