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View Full Version : 4 BAR on LR and 2 BAR Spring on top RR



romeropolo
05-21-2011, 10:25 AM
I have a DW7 with this set up LR and RR shocks in front of axle 225 springs, 8-3 LR shock and 95 on RR. 1050 pull bar spring at 22 degrees. 7 inches of rake on J-Bar even with pinon. LR bottom bar 5 degrees, top bar at 22 degrees. RR bar at 0 degrees. 70 lbd of bite w/ driver...20lbs w/o driver.

Question- What changes need to be made to have more body roll to load the RR comming off the corner?

washeduptoo
05-21-2011, 12:08 PM
When we ran this set up, we ran 60-80 lr bite without the driver. Thats a lot of rake in the jbar. Try about 5in of rake with it one hole below pinion if its a 9in. The 2link rr is a normal tight set up and doesn't really add drive to the rr but its pretty good in the slick. I would also put the rr shock behind to help. Be sure that the lr axle tube will almost touch the underslung. Just some things to look at. Good luck.

cavemod
05-22-2011, 02:14 PM
how bout a 200 spr on rr with a 94 or 93-5 shock??

washeduptoo
05-22-2011, 04:50 PM
If your question was directed toward me. We ran the 200 also on rr, a little looser in and car seemed to roll over onto the rr more but it was an 11 inch spring. When we ran the 200 we didn't have as much angle in the spring either(moved perch farther toward wheel). Went to a 225 13inch spring when we moved perch.
We ran a 3030 Bilstein(off the shelf) usually on the rr, I have no experince with those shock numbers.

cavemod
05-22-2011, 05:39 PM
the intial question was about body roll and the spring and shocks he"s using tells me that he runs afco or pro or integra out of the box shocks with no custom valving.When I ran a 3 link i tried a pair of 225 on back and the thing wouldn't roll either but when i dropped to a 200 it got some roll and when the track was smooth the 3-5 was better then a straight up 94.I also agree with the angle of the spring will take away rate.This season i will be doing the same as this post 4 bar lr and clamped up rr spring on top with rr shock behind.From what I've seen this is a very succesful setup around here.GRT mods did extremely well with this setup on all types of track conditions the past couple seasons.i believe the 30/30 bilstein is a soft shock comparable to a 93.my point being I think he's to stiff in the rr shock and spring package to get any body roll.How much shock travel are you getting on the rr with the 225 and 95????Does it carry the lf???

washeduptoo
05-22-2011, 06:01 PM
My mistake, thought you were directing your question toward me, sorry. You've got good points and we were also successful with the 4-2 set. Best of luck to both of you.

romeropolo
05-22-2011, 08:17 PM
The car doesn't carry the l f at all. This what im trying to do.....what change makes this happen....I have integras on the left and pros on the right.....I get around 4 inches of travel on the rr

romeropolo
05-22-2011, 08:31 PM
The car doesn't carry the l f at all. This what im trying to do.....what change makes this happen....I have integras on the left and pros on the right.....I get around 4 inches of travel on the rr

Thank you for the info in advance....

oldtrackchamp4x
05-23-2011, 03:19 PM
I ran this setup last year and am running it again this year.The car is fast it is a DW-8. This is how my car is setup. LR 250 spring 3r 5c shock for tacky 2r 8c for slick. RR 175 spring, spring should be behind rear end, 3030 low pressure for tacky 5r 2 c for slick. 60-70 lbs LR bite w/o driver. I run the r bar in center hole when tacky, and drop to bottom hole when slick," three hole bracket". My left upper bar is one hole higher than you have yours. Jbar center of pinion with 4.5 in of rake.If all you want to do is hike the lf put bite at 100-110-lbs. with the above setup. If you want to see how the car works go to youtube and search " J D Jurad". Im in the 4x car. Good luck.

romeropolo
05-23-2011, 05:24 PM
[QUOTE=oldtrackchamp4x;1379307]I ran this setup last year and am running it again this year.


Man.... that is the info I was looking for. Did you ever try the shock behind the axle on the RR?

oldtrackchamp4x
05-23-2011, 06:42 PM
That is where it needs to be. I'm sorry, I messed up and said spring when i ment the shock. Spring on top, shock behind. Let us know how it works. Good Luck.

xxx8x
05-23-2011, 09:15 PM
On a 2 link lr spring in front rr on top. whats the best shock in front or behind on rr.OR IS IT DRIVER PREF.

romeropolo
05-23-2011, 10:24 PM
I don't know but I am going to go with 70 lbs of bite and shock behind on rr

washeduptoo
05-24-2011, 07:15 AM
The shock behind on rr will tighten car up some. Good luck.

romeropolo
05-24-2011, 11:00 AM
In the begining of this I wanted more bite coming off the corner...Im not sure if adding 50 lbs of bite and moving the shock behind on the RR will do this....but I am going to give it a shot.....this is ALOT of changes and I dont want to tune my self out of a fast car...

28m
05-25-2011, 11:45 AM
Seven words...Put the spring behind on the RR.

You will get the roll that you want and more drive coming off. Dont add the LR bite just yet. Spring on back when on the gas adds more LR bite and drvie.

You will think you have a new car. PROMISE :)

xxx8x
05-26-2011, 04:00 PM
thanks, 28m.

powerslide
05-28-2011, 06:38 PM
Seven words...Put the spring behind on the RR.

You will get the roll that you want and more drive coming off. Dont add the LR bite just yet. Spring on back when on the gas adds more LR bite and drvie.

You will think you have a new car. PROMISE :)

you will have a new car alright. it will have your left front so high up the air you wont be able to see and you will be pushing the nose across the track. this will be compounded if your pullbar travels alot.

Mosidebite
05-28-2011, 08:35 PM
Gotta agree with ^. Our Hoffman car was at it's best on the 4-2 with spring on top to keep left front from being up in the clouds. We actually used a little stiffer rr spring, a 250. With a 200 on the left rear. However used a 3 comp and a 5 reb shock to keep it over on the right rear. RR bar angle was critical to our set up, we always had to have 8 degrees in the lower to keep it from leveling out or actually neg degrees and causing a TIGHT on entry thru the center. Also with the stiffer RR spring we used a little lower rear roll center.

28m
05-31-2011, 11:41 AM
Question- What changes need to be made to have more body roll to load the RR comming off the corner?

Weird, I thought he was asking how to get more roll?

So let’s say you put the spring behind and your LF is "in the clouds", I would add pre-load to your pull bar, stiffen the spring or switch to a biscuit bar. Since your spring will drop on the RR, you might stiffen the RR spring a bit. This will keep the front down, add spring pressure to the RR adding side bite. The stiffer RR will add drive to that wheel as well. This is good because you will be adding drive to the LR by that spring dropping on the RR.

Another question has to be the type of track you run on. Heavy, slick, banked, flat?

powerslide
05-31-2011, 12:02 PM
I think your understanding is correct. only thing i will say in addition is that the spring behind on a heavy/rough track is about impossible to drive. JMO

We learn by trying so give it a try but i wouldnt spend too much time on it.


Weird, I thought he was asking how to get more roll?

So let’s say you put the spring behind and your LF is "in the clouds", I would add pre-load to your pull bar, stiffen the spring or switch to a biscuit bar. Since your spring will drop on the RR, you might stiffen the RR spring a bit. This will keep the front down, add spring pressure to the RR adding side bite. The stiffer RR will add drive to that wheel as well. This is good because you will be adding drive to the LR by that spring dropping on the RR.

Another question has to be the type of track you run on. Heavy, slick, banked, flat?

romeropolo
06-01-2011, 12:34 PM
This weekend I went with moving the LR shock behind moved the pull bar over (left) 1 inch(it was right of center 1 inch).

I race on a VERY small bull ring(VENTURA RACEWAY) with very little banking on the bottom. (which is the prefered line) I couldn't keep it down on the bottom and still had the same bite off the corner.

Next I'm going to go from 30lbs of bite to 70lbs. Any Ideas??????

washeduptoo
06-01-2011, 01:23 PM
Did you move the lr shock behind or the rr shock behind? Have you tried to reduce the rake in the jbar?

romeropolo
06-01-2011, 02:32 PM
I moved the RR shock to the rear and moved the pull bar to the left 1 inch for this weekends race and the car was tighter in and had little drive off. I still had 30 lbs of bite in it.......I am going to put 70 lbs of bite in it for the next race.

****Question is will the change give it more drive off or just make it even tighter?

charcoal01
06-01-2011, 02:49 PM
I moved the RR shock to the rear and moved the pull bar to the left 1 inch for this weekends race and the car was tighter in and had little drive off. I still had 30 lbs of bite in it.......I am going to put 70 lbs of bite in it for the next race.

****Question is will the change give it more drive off or just make it even tighter?

is the spring on the shock or is the shock separate from the spring, and the spring is on top of the axle housing?

how much lead do you have on the car and where?

oldtrackchamp4x
06-01-2011, 02:51 PM
On my car when i up the bite it is looser in and more drive off.

washeduptoo
06-01-2011, 02:53 PM
Both changes you made would make the car tighter, one on entry, other one on the gas. Increasing lr bite should loosen entry some and tighten the car off. How close are you to bottom out rf shock? Are you trying to loosen the car up some? IMO, look at the jbar rake, I recommended 5in of rake and the dw8 guy recommended 4.5in of rake. Good luck.

charcoal01
06-01-2011, 02:55 PM
On a 2 link lr spring in front rr on top. whats the best shock in front or behind on rr.OR IS IT DRIVER PREF.

depends on if you have a split valve shock or not. if its a straight 5-5 or 4-4, it wont matter as much because the axle sees the same resistance in and out. on a split valve its going to make a difference.

i ran a 4-3 on my rr, spring on top with lr spring in front, shock behind. car was a little tight in. i took the rr and moved it to the front, freed me up just enough and felt much more comfortable to me so i left it there.

theory is as the axle wraps forward on decel, it momentarily sees an increase in weight on that wheel as the shock is on the compression side, thus planting the rr a little more than the left (if shock is behind). does the reverse if you put it in front. its not a huge swing one way or the other, just a fine tuning tool.

romeropolo
06-01-2011, 04:29 PM
is the spring on the shock or is the shock separate from the spring, and the spring is on top of the axle housing?

how much lead do you have on the car and where?

On the RR....225 spring on top, 95 pro shock behind axle, 1/4 inch lead in RR. 7 inches of Rake in the J bar.

Two things I want to change is the bite and the rake. But I will make the bite change first from 30lbs to 70 lbs on the LR....if that dont give me the forward bite I want I will make the J bar change.

28m
06-01-2011, 06:49 PM
theory is as the axle wraps forward on decel, it momentarily sees an increase in weight on that wheel as the shock is on the compression side, thus planting the rr a little more than the left (if shock is behind). does the reverse if you put it in front. its not a huge swing one way or the other, just a fine tuning tool.

I agree with the last statement here..."Its not a huge swing" If you’re so tight getting in that you can’t keep the car on the bottom and your lacking forward drive...the shock placement isn’t your answer. JMO of course

J-bar won’t help drive off necessarily. It will help your entry which will let you keep momentum and ultimately make you faster... that is a lot of rake to me and is probably why the tight entry.

Too both loosen the car getting in and tighten coming off, increase your LR spring rate and decrees your RR spring rate. This will be a much more effective adjustment than shock placement but not as drastic as moving your RR spring to the back of the housing like I suggested earlier. I guess it depends on how close you are. .1 second off…move the shock .5 second off…change springs 1 second off…move the spring.

I agree with you adding more LR bite. Pretty sure your headed the right direction with that.

oldtrackchamp4x
06-01-2011, 11:16 PM
I also agree on the right rear spring being to heavy.I ran 225lr and 175 rr. Changed to 250lr. kept 175rr and the car got way better bite off. Good Luck

powerslide
06-02-2011, 01:08 PM
This weekend I went with moving the LR shock behind moved the pull bar over (left) 1 inch(it was right of center 1 inch).

I race on a VERY small bull ring(VENTURA RACEWAY) with very little banking on the bottom. (which is the prefered line) I couldn't keep it down on the bottom and still had the same bite off the corner.

Next I'm going to go from 30lbs of bite to 70lbs. Any Ideas??????

Why couldnt you keep the car on the bottom was it pushing or was it sliding the back up the track?

romeropolo
06-02-2011, 03:08 PM
Why couldnt you keep the car on the bottom was it pushing or was it sliding the back up the track?

The car sliding up the track. It was not pushing...

28m
06-03-2011, 10:59 AM
LOL, great question Powerslide...I just assumed it was pushing.

In that case, you are loose getting in or no side bite...work on that J-bar.

powerslide
06-03-2011, 04:26 PM
I would get the large split out of the jbar drop it on the frame then go from there 5in split instead of 7.
you never confirmed 9in or q/c so i am basing this off 9in. if its q/c you need to move the pinion end to reduce split.


How much trail you run?

Sounds like if he fixes entry/middle he will find alot more speed coming off.

tried a wheel spacer on lr or rf?

washeduptoo
06-03-2011, 04:57 PM
Hey powerslide, for my own knowledge what does using a spacer on the lr or rf do? Thanks

romeropolo
06-04-2011, 08:57 PM
I would get the large split out of the jbar drop it on the frame then go from there 5in split instead of 7.
you never confirmed 9in or q/c so i am basing this off 9in. if its q/c you need to move the pinion end to reduce split.


How much trail you run?

Sounds like if he fixes entry/middle he will find alot more speed coming off.

tried a wheel spacer on lr or rf?
I Just ran the heat with 80 lbs of bit and I am good to go now.....