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frontrunner
02-17-2011, 07:42 PM
Why does going from a 94 shock on lr to a 95 on left rear work better when the track dries out... I run 94 lr & 95 rr till track dries out then I run 95 lr & 94 rr. but I just wanted to know why the stiffer shock 95 works better when dry?? I always thought that the softer shock would make the lr work better but if Im wrong can smeone tell me?? Oh yea it is a muti. leafspring car... Thanks for any info

junebug
02-17-2011, 11:35 PM
this is just a guess....havent messed with leaf stuff in a while but maybe it keeps the car from wedging up on entry so fast and lets u get in the corner better.....then you can carry more speed threw the center, and thatll help it on exit....ive wondered about trying a 6or 7 compression 3-4 rebound on lr of a leaf car when tracks dry

frontrunner
02-18-2011, 07:56 PM
I am loading the rr more the with the shocks I run when it turns dry slick I think becouse I am running A 3 rebound on lf & a 75 on rf so transfering weight to the rr quicker a good Idea seems 2 be but just aking for more info..it is a muti leaf mod... Thanks for the info............

Dirtrunner35
02-18-2011, 08:09 PM
This is some great reading

Stated simply, use shocks to alter/adjust/change a condition known as, "Instantaneous, Dynamic, Diagonal" - hereinafter refered to as "IDD".

Picture a car sitting on four wheel scales. This car has absolutely equal weight distribution, so all four wheels weigh exactly the same.

Now, if you were to push down on the exact center of this car, all four wheel scales would increase equally.....everybody agree?

If I were to add shocks to the RF and LR that had high - or higher compression values, and I pushed down on the center of the car, what would happen????

That's right....The RF and LR scales would show momentary increases over the other two scales due to the resistance of the two shocks, but everything would even itself back out again after the shocks bled down, and all four wheels would be equal in weight again......OKAY???

What happened here was a change in the IDD. For just an instant, there was more diagonal - or crossweight - with the RF and LR momentarily being more heavily loaded than the other two wheels.

But, once the shocks bled down, the setup returned to the equal-wheel-weights setup.

Now, go the opposite way.....lift slightly on the car.

All four wheel scales should show equal reduction of weight on all four wheels.

Add shocks with more REBOUND to the RF and LR, then lift again.

The RF and LR scales should show a momentary, increased reduction of weight over the other two scales until the shocks allow the wheels to go into full droop.

In this case, we have, momentarily, reduced the diagonal - or crossweight - for an instant.....

......which explains - for those of you who have read the Penske shocks setup manual - the suggestion to set the car up with a slight push on turn entry, dialing it out with LR rebound.

LR rebound induces a momentary reduction of crossweight upon turn entry, but allows the suspension to return to its original setup for turn exit.....effectively giving you one diagonal - or crossweight - for turn entry and a different one for turn exit.

A reduction of RF compression would probably serve the same purpose, but I am most comfortable working with rebounds - although I WILL monkey with compression when my back is against the wall.

With the right shocks, you could actually instantaneously DECREASE the diagonal or crossweight for turn entry, and INCREASE it for turn exit - or vice-versa.

The above is an over-simplified example of how it SHOULD work, and as we all know, nothing in racing is really "simple."

But, if you can get the concept of "controlling" body roll or weight transfer out of your mind, and visualize instantaneously - and momentarily - increasing or decreasing the diagonal or crossweight for better turn entry or exit, and you SHOULD begin to grasp the concept of shock tuning....

frontrunner
02-21-2011, 04:09 PM
Anybody else have any thoughts on this tacky 75lf 75rf 94lr 95rr and for dry 763lf 75rf 95lr 94rr.. Thanks

Straight2TheFront
02-22-2011, 11:54 AM
From what I understand, when increasing the rebound on the left side, particularly the left rear, it holds the weight on the left rear longer. This will tighten the car getting in the corner and make it better when track slicks off.

frontrunner
02-22-2011, 06:53 PM
ok thanks for the info ? what does anybody think about the 763lf & 75rf for dry track... The track I run on does dry out quick.. Sooo need for slick...

Thanks for the info......

Dirtrunner35
02-22-2011, 07:48 PM
Shock wedge



......which explains - for those of you who have read the Penske shocks setup manual - the suggestion to set the car up with a slight push on turn entry, dialing it out with LR rebound. MORE REBOUND



If I were to add shocks to the RF and LR that had high - or higher compression values, and I pushed down on the center of the car, what would happen????

That's right....The RF and LR scales would show momentary increases over the other two scales due to the resistance of the two shocks, but everything would even itself back out again after the shocks bled down, and all four wheels would be equal in weight again......OKAY???

frontrunner
02-22-2011, 08:14 PM
Thank u.....Im just asking if there is any other shocks that will work for a dry track I have tried 75lf 753rf and I have tried 75lf 763rf and I have tried 763lf 75rf on dry and that seemed 2 work better. Just asking if thats it or is there more shock options that could work.. It is a banked 1/4 mile & it is a muti.. leaf just leafs not floated or anything else just leafs... Thanks again for any Info....

frontrunner
02-24-2011, 05:05 PM
btt...........