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FAH-Q
02-07-2012, 09:39 PM
when and why would you want to limit the rr travel. i know you could to keep the spring from coming unloaded but what effects will that do to the car? i also heard through racewise that you could even compress the rr a 1.5 and it would tighten car up tramendously but im not clear on how it works.

andy16
02-07-2012, 09:57 PM
imo... i limit my rr about a 1/4 inch before shock tops out. i believe that if the chassis is so upset that the r/r is unloaded enough for the spring to come unseated that there are problems like one h*ll of a rut or hole. use zip ties to keep the spring in the bottom bucket and a allstar blue teflon shock protector on the top. on my shocks it helps guide the spring and eliminates all the clanging that used to go on. also may have to trim the bottom of the shock protector 1 or 2 inch depending on how much you compress spring. i believe that if you tie up your rr too tight that you may cause the tire to skip over ruts and holes and i want all my tires touching the ground as much as possible. i limit it a 1/4 inch before shock tops out because you dont want to top out shocks could damage it. also when making a spring change i can jack up rear of chassis and rear end will hang on the l/s and r/s chains w springs unloaded. just pop your shock or spring out pop a new one in and no fumbling w two jacks and all that bs. works great for j bar changes as well. ??? If you preloaded the rr against the chain would really make a spring changer a pain in the ... unless used spanner wrench and all that. i never been to racewise but i def advice against preloading rr, in my humble opinion.

FAH-Q
02-08-2012, 12:23 AM
should you use a 14 inch rr spring or a 12 inch spring to keep it from unloading.

sj valley dave
02-08-2012, 01:19 AM
Most people I know use a 12" RR spring..no reason to use a 14" spring....

fox1162002
02-08-2012, 08:21 AM
There is a video on you tube that's shows the rr area of a 4 link car as soon as the gas is picked up and the lift bar is loaded the rr spring will be off the nut and unloaded like the lr but its only off like a 1/2 to 3/4 of an inch in the video. I've worked with chaining it but never could find a good medium spot it was either way tight or not much change. But with some R and D I think it would be able to work.

Matt49
02-08-2012, 09:39 AM
I know some folks that use a RR chain to limit the upper bar angle to keep them tighter off the corner. Personally, I think just lowering the top bar on the frame or a shock adjustment (more RR rebound) are better fixes.

andy16
02-08-2012, 04:14 PM
well i guess it mat be possible to get hooked up enough on the strait to have the rr get up on the bars like the lr but even then chaining it to keep down w the spring would limit forward traction? the only good i see from that scenario is it would stp it from slamming down back on the spring? the spring is floated on a bird cage so torque arm wouldn have a direct effect. what if you kept one spring floated and added another spring w long clamp to rear so when you got on the gas the torque would compress that rr spring ??? but i think they tried that too. tracks i run at dont have that kinda traction and the corners never really end im 99.9% sure my rr isn coming unloaded its my lf that comes unloaded when i hit the gas.

mab475
02-08-2012, 05:50 PM
There is a video on you tube that's shows the rr area of a 4 link car as soon as the gas is picked up and the lift bar is loaded the rr spring will be off the nut and unloaded like the lr but its only off like a 1/2 to 3/4 of an inch in the video. I've worked with chaining it but never could find a good medium spot it was either way tight or not much change. But with some R and D I think it would be able to work.

Do you happen to have the link to that video?

fox1162002
02-09-2012, 01:54 AM
Not right off but I searched dirt late model suspension cam and its actually a com showing the lift bar. But you see the rr birdcage and shock and spring.

mqdirtracer57
02-09-2012, 11:12 AM
I recently bought a Rocket and the RR is limited...I was curious of why. I actually thought about taking it off and limiting the LR. Just trying to keep my set-up simple

charcoal01
02-09-2012, 12:08 PM
We set it at an inch and a half drop from ride height on the rr. It's really just before the spring unloads. Tightening the chain will tighten the car up as soon as you get on the gas, it basically holds cross in the car off the corners.

MasterSbilt_Racer
02-09-2012, 03:42 PM
I recently bought a Rocket and the RR is limited...I was curious of why. I actually thought about taking it off and limiting the LR. Just trying to keep my set-up simple

I would limit the lr first to avoid shock damage, but both can also be tuning tools.

FAH-Q
02-09-2012, 09:07 PM
should i take the 14 inch spring off and put a 12 back on . and maybe use the cable to keep from unloading. we had seen videos of it coming off the seat. not as much as the lr though.

AmickRacing
02-09-2012, 09:49 PM
The 14" spring isn't really hurting anything over the 12" spring, other than it'll weigh just a little more.
Long as you're not coil binding the spring (any length), and as long as you have room on the shock body to adjust it, that's the important thing.

andy16
02-09-2012, 10:38 PM
i propose you take a look at gerald davis #28 rear suspension video. i have raced w him before in steel block bandits and he won the race. he is using a up to date chassis w up to date setups on tracks in my area. i trust him over the other video of the passmore car. nothing against the passmore but i cant tell if he is making true laps. he slows down a few times does some odd things at the time the rr is coming unseated. on all the consistent smooth laps passmore makes the spring stays loaded. gerald davis spring is 25-50% collapsed at all time. the passmore car is running a crate motor i believe also. gerald is running a limited motor w steel block. just have to apply this info to your program i guess. im still not convinced to preload the rr. i mean are you supposed to scale it with the chain on there preloaded or just supposed to do it at the track. if you just do it at the track the reason you get so tight is the more you tie down and lower the rr your also affecting your ride height. and the lower the rr is the higher the lr is. so your prob adding a lot of bite when you do this.

mab475
02-10-2012, 01:35 AM
They are preloading when the car is on jack stands with the rear hanging. When the car is setting on the ground the ride height isn't affected. Just limits how far the rr can rebound.