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View Full Version : What's Better? RF Set Up and Drive



DirtRacer9x
10-02-2014, 03:11 PM
Pinned down hard RF? Does this make it so you have no drive off or once completely tied down hard will it automatically make that point of the car a fixed pivot point for weight transfer rearward? Or, would a pop off or less rebound low speed be better? What's the difference because I've heard both being ran. Pro and Cons?

grt74
10-02-2014, 06:28 PM
I'm really not being a wise guy here even though it may seem like it,what ever it takes for it to work for you,there isn't a perfect answer for this,ill bet there won't be a lot of direct answers on this,test,test,test,but you can achieve drive with the rf pinned down

DirtRacer9x
10-02-2014, 06:37 PM
Ok so how can you achieve drive with RF pinned down? Pros and Cons over not being pinned.

Bcollins82
10-02-2014, 06:41 PM
Exactly what grt74 said. A racecar works as a package. If you just bolt on a RF with extreme rebound numbers and keep it pinned without changing anything else, you'll be wondering how a car could lose so much drive. It's all about finding what works together.

DirtRacer9x
10-02-2014, 06:51 PM
So again care to enlighten how you get drive with a pinned rf?...

Bcollins82
10-02-2014, 06:57 PM
Ok so how can you achieve drive with RF pinned down? Pros and Cons over not being pinned.

By gaining back the dynamic crossweight you just lost by traveling the RF farther and keeping it there. How do you do that? Like grt74 said, test, test, test. Pros, getting the nose down, butt up attitude in the car helps a lot of different things like weight transfer and aero. Cons, super rough tracks? Lol

big88fan
10-02-2014, 07:00 PM
You don't, its about momentum with the rf pinned over with rebound. Also just because its on the rf doesn't mean the rebound numbers are crazy high, soft spring with a bump or coil bound stack. Lots of options and no one is going to give you the direct answer to your question

Bcollins82
10-02-2014, 07:12 PM
That's true on the shock big88fan, that was just an example.

DirtRacer9x
10-02-2014, 07:31 PM
So example. Lets say you're pinned on rf. are you heavily pinned on the high and low speed stuff or just the high speed and bleed off rf with low speed? I'm trying to understand exactly these 2 different ways to do things. I know I won't get an exact answer but when doing these different set ups will you have say the RF pinned more and loner on a sweeping track vs the track that has straight always? Is the car driven strictly off of cross out of the rf and LR hike when pinned that heavy? If someone can give scenarios as to what works better and why that would be great. Just opinions at the very least.

grt74
10-02-2014, 10:08 PM
all i can say its going to be a ton of work,notes and testing is where its at,and saying that I'm learning more every day with different set ups,hell I've got 3 different rf shocks depending on what i want to do,if you quit hunting you'll find yourself in the rear

Brian Gray
10-02-2014, 10:32 PM
You are thinking way to much. Your looking for a magic bullet . they don't exhist!

Some guys like the car pinned over why? Too many reasons. Same reason some dislike it.

Listen to the car and give it what it wants. That's the honest answer.

If you want just an opinion I like my car pinned over on the rf because it gives me a feeling of stability . it may be false and at times it hinders my performance . but I fee like the cat is easier to manipulate when it is steadied on the rf. That's why I prefer this set up. Its not for everyone though and its not always fast

DirtRacer9x
10-03-2014, 02:01 PM
I'm actually looking for a reasoning. My thinking is I'd possibly want to be tied down more on a continuos radius/arc track so the car steers more positive and maintains momentum. While a track like a paper clip I'd want that thing to release and drive off harder. This is what I'm trying to figure out.

HuckleberryB4
10-03-2014, 02:38 PM
The best thing to do is try it and test your reasoning.

DirtRacer9x
10-03-2014, 02:49 PM
Or try and gather input to cut back on time which is what I'm trying to do here.

FlatTire
10-03-2014, 04:16 PM
DirtRacer9x-

I wouldn't look at it in the terms of sweeping vs. paper clip. I'd go by what I feel and what my crew chief tells me the car looks like from the middle of the turn onto the straight-a-way. I like the car laid over on the RF when I need to steer on entry to the middle usually slightly off of the throttle. When I'm ready to apply more throttle and exit, I want the RF to start rising back up to aid in forward drive. This is what works for me. We've had the RF laid over onto the straight and thought we were giving up forward drive on most nights. However, there are guys running the RF compressed all the way around the race track making good forward bite on all sorts of tracks.

Shocks, bumpstops, dual stage springs, bump stop shims all effect this. The "attitude" of the car and "timing" of these events that induce roll all play a part and thats what these guys are trying to point out. Another thing at play here is how compressed the RR is. That also helps make forward bite. Depending on what you have at the RR, you can load it greatly or not so much as you compress RF. That added to the other things you mentioned with LR hike, and cross all play a role.

Go find some pics/vids of Brandon Shepard. He runs a lot of RF pinned set ups.

There are other ways to help the RF steer better than pinning it over which involve front end geometry.

I can relate to your frustration, and the 4m tech board isn't what it once was. These cars are getting so competitive and the gains so small these days that those that are in the "know" and really understand whats going on aren't talking anymore. The cool part of that is, all that information can't be bought or gathered on some forum like this one. If you do your homework, teach yourself, and experiment, you can find gains that others don't know about.I like it that way because it rewards the guy who uses his brain, instead of the guy that uses his pocket book.

Bcollins82
10-03-2014, 04:25 PM
Or try and gather input to cut back on time which is what I'm trying to do here.

The info you are seeking is what you test yourself, and pay your shock guy and chassis builder for. Most guys on here don't mind pointing you in the right direction, but most have spent the time and effort to figure out what works best for them, so you aren't going to get very many to give specifics on a national forum. Besides that, you'll get a different answer from every person on this, because as Brian Gray told you, it is mostly about your preferences, and what your car or track needs. As far as your continuous arc vs paperclip theory, that is a generalization and an assumption. Both types of setups win on both types of tracks. You can gain your drive back having the car pinned over, but you'll have to work at it to get that drive and balance back. I will say your traction device (lift arm or pull bar), and the setup on the left side of the car is where I found the most gains having a car pinned over. Good luck!

DirtRacer9x
10-03-2014, 08:19 PM
This is the info I was wanting to hear. I'm fairly new to dirt so I'm trying to see how most set ups work on paper and why. Then what is most consistent and why with its pros and cons. I would like your thoughts on the most consistent set up. Pinned or not on rf. Consistent is what I want strictly.

setup479point2
10-03-2014, 09:02 PM
You are the wild card . Every driver and every car like different things . I had one car I worked on with 3 different drivers on the same track . Every driver required different springs and bite to get the feel they wanted , every one won races in that car . Even basic setup is different in different parts of the country , I help drivers from all over the country through this forum , what works in the south may not work in the midwest . You have to find , through running and testing , what you like , what your car likes.

DirtRacer9x
10-03-2014, 09:36 PM
I think you're not understanding the in depth I'm asking. What is the overall most consistent set up? Meaning do you even look at times every lap and over the course of the race and study why it's falling off? This is what we do on asphalt and so far I haven't seen a trend on dirt AT ALL with anyone doing this.

setup479point2
10-03-2014, 10:22 PM
I know what you want , and it doesn't exist . I have 18 drivers across the country , NO 2 are the same setup , frontrunners in multiple classes and many different chassis . For one I tie down , for another its 50/50 , for another its stiff springs , for another soft , for one its no bite , for another 300 lb. . You have to find out what YOU need . Start with what your chassis maker recommends , and go from there. When you start racing and have a problem let us know , plenty of us will help .

TALON75
10-04-2014, 01:18 AM
I have six different rf shock sets, and have used more than these six. Dirt racing variables change ten times more than asphalt, you have to change with the conditions. The consistency you want is probably unattainable, but you could try a 375-400, with a 3 compression and 8-10 rebound shock.

hpmaster
10-04-2014, 07:22 AM
I think you're not understanding the in depth I'm asking. What is the overall most consistent set up? Meaning do you even look at times every lap and over the course of the race and study why it's falling off? This is what we do on asphalt and so far I haven't seen a trend on dirt AT ALL with anyone doing this.

Dirt is pretty hard isn't it? Won on pavement faster than you have on dirt huh? I won't waste your time or mine explaining this, what you are looking for isn't attainable on dirt. Now you talking down to dirt guys while asking them for help, like we have no concept of trying to figure out why times fall off during a race is in short, NUTS. Having set up winning cars on both dirt and pavement you are exhibiting an extreme case of the first or maybe second year new on dirt buthurt syndrome "I won on pavement and SHOULD be doing better than this on dirt". No instant miracles here, sorry.

grt74
10-04-2014, 07:58 AM
I think you're not understanding the in depth I'm asking. What is the overall most consistent set up? Meaning do you even look at times every lap and over the course of the race and study why it's falling off? This is what we do on asphalt and so far I haven't seen a trend on dirt AT ALL with anyone doing this.

track changes to much on dirt,you'll have to compare it to cars that are fast on the day your there,i have a friend that runs asphalt and I've seen what they do when there practicing,in dirt its not so easy,you can be in the ballpark(or even faster for the way the track is when your practicing)but the track may not be the same when you race,were back to test,test,test,also it think your looking for some #'s,your just not going to get them,1 almost all the cars are 1/4 to 1/2" different on the rf or more and thats a factor,2 the cars are getting so equal that no one is going to give up something that is got them up front

DirtRacer9x
10-04-2014, 11:45 AM
Well I appreciate the responses. We haven't been struggling like most do that's at we computer with weekly. We're actually very good. But the select few drivers we have come out to our area especially coming up are a tick faster and times don't fall off as much as we have. There are things I've noticed is different with the few cars I can see visually. Shock wise I can see the attitude of what they're doing. Do any of you know what Bloomquist ran In the big race? Statistically I feel pretty confident to say 99% don't and haven't studied what happened that race nor know his times and have watched every lap as the car changed. He made everyone look like a fool. So if someone can relate on this level how and how our team operates feel free to message me and see if we can help one another.