Moving RR in

[bigk44]

Will moving the RR in (6" bs instead of 5") have the same effect as moving LR out? Tighten the car up on a slick track?

[7uptruckracer]

Yes and No they tend to leave the RR alone because it effects the car in more places then the LR. People think you want to tighten everywhere in the slick and that isn't true you don't want to overtighten your entry which that might do you need to keep the car turning in and through the middle but add drive off and the LR will do that while the RR might hurt you more elsewhere IMO

[huckleberry_hound]

Will a spacer on the left rear help in the slick?

[grt74]

Yes it will tighten the car
it will roll quicker,scotch harder
but not the same as moving the lr out,moving the lr out does two or more things,car drives straighter and adds drive because of the fact that just by adding the spacer it will drive the tire in the ground harder
put the car on jack stands and measure from the floor to the rim and then put the spacer on and measure again,it will be closer to the floor
there are other factors in there also too

[huckleberry_hound]

What size wheel spacer would be recommended? 1 inch?

[crewchief32]

I hate to tell you this but adding a wheel spacer to the lr will NOT add drive. It will tighten entry and loosen exit.

[grt74]

crew have you run one???then when you put one on why does the car drive straighter off the corner???and yes it does tighten the entry also because it moves weight from the lr to the rr,if you do no other adjustments it will tighten up the entire corner,if you dont think so or it doesnt youll need to go over your car,something is not working correctly,thats my opinion for what its worth
hound 1" is what we use 2"is a huge adjustment for us and if we need that much we work on the car somewhere else

[crewchief32]

First off the further a spring is from the contact patch of the tire the less effective the rate of that spring is and actually acts softer equaling less drive. The only reason it would drive off straighter is because of the increased roll steer you gained by putting it out there. So it sound like you need to go over your car.

[grt74]

First off the further a spring is from the contact patch of the tire the less effective the rate of that spring is and actually acts softer equaling less drive. The only reason it would drive off straighter is because of the increased roll steer you gained by putting it out there. So it sound like you need to go over your car.

if you increase roll steer the car will be looser not tighter,all im saying is try it,and do what i said above as far as measurements ect,one thing that i learned from an old man the tape measure never lies
i do agree with you that the spring is farther away from the tire but under full acceleration has little effect,
if you put the spacer on and the tire is now 1" closer to the ground (or more drop) this adds dynamic wedge and wedge = drive,also im on here to try and help thats all,not a pissing match,check me see if im wrong,im sure that im not perfect because i cant walk on water

[MasterSbilt_Racer]

Moving the lr wheel out does take weight off of it if no other adjustments are made. It also moves the center of the thrust generated by both rear tires to the left. The farther to the left that thrust is, the more the car wants to turn right.

What wins out depends on quite a few factors.

[charcoal01]

I've always found the spacer deal to make the car tighter all the way around, but mostly on exit. Never ever felt like it was looser.

[Egoracing]

MasterSbuilt_Racer did not say it made it loose he said it makes the car want to turn right, to turn right the drive of the car is toward the LR more than the RR. Put it out there far enough and the car will spin out with the rear end going to the left. Imagine a push so bad that the rear goes to the infield instead of the wall. If the driving force is to far to the right then the right rear wants go to the right and the car is called loose as the rear want to spin out to the right.

[grt74]

masters and ego thanks for helping me explain this a little better,but also if you put the car on the jack stands and then jack the rr like its loaded in the corner,then measure from the lip of the rim to the floor without the spacer,then put the spacer on and measure,i think youll find that the lip of the rim will be closer to the floor,i just used 1" as a reference,ill leave it alone now got to race tonight

[let-r-eat]

grt74. Since you race with both back wheels on the ground I don't think that LR will be down into the track any further.The motion ratio of the spacer lessens the wheel rate. The vertical axis through the center of gravity has changed and therefore will make the car tighter. That's one reason why the contact patches on one side of the race car should be aligned and adjusting offsets should be done to one side of the car in most cases.

[Egoracing]

There are not many builders if any that line up the front and rear tire tracks, typically the LR is slightly inside the LR and the RR can be WAY inside the track of the LF.

[dchamp3]

Barry Wright lines the left sides up ,but we changed ours moved left in a little.

[drtrkr244]

Adding spacer to left rear definitely tightens car through the whole corner.When you space out the left rear, you have widened the rear track, which keeps more weight on the lr on exit.This works so well Rocket and Mark Bush recommend this at all times for Rockets.

[7uptruckracer]

The LR rear Spring and Wheel spacing wise only really does anything on exit everywhere else your for the most part dealing with the handling based off body roll and hike, roll steer, as far as weights your weight is transferring rear to front and inside to outside so the LR is the big loser weight wise so the spacer doesn't really effect anything entry to middle Nearly as much as exit. I agree the Wheel spacer is an effective and useful change to tighten exit especially now that they are doing so much geometry wise to get the cars to keep turning in all conditions and the Wheel spacers eliminates as many compromises as possible which is what we are all after

[fastford]

i never run the left rear out of line with the left front, although ive tried and didnt like it, its almost like a crutch, but heres how i look at it, if you have ever rode a 3 wheeler, where the left rear tire is out farther than the front , then you know you have to lean way to the right to turn left, if you lean left any at all then even though you are turning the wheel left , its going to turn right like master built stated above , i think tracking is more important than trying to gain a little dynamic wedge by moving lft out, on todays set ups, there are a lot more ways to gain foward bite than using a spacer, JMO

[MasterSbilt_Racer]

i never run the left rear out of line with the left front, although ive tried and didnt like it, its almost like a crutch, but heres how i look at it, if you have ever rode a 3 wheeler, where the left rear tire is out farther than the front , then you know you have to lean way to the right to turn left, if you lean left any at all then even though you are turning the wheel left , its going to turn right like master built stated above , i think tracking is more important than trying to gain a little dynamic wedge by moving lft out, on todays set ups, there are a lot more ways to gain foward bite than using a spacer, JMO

I used to use spacers all the time on almost any wheel. Now I never consider it. Like you said, there are just a limitless number of things to adjust today.

[7uptruckracer]

Most all the new rockets minus the black runs it standard, I haven't really looked at all the geometry to see why. Even Mark brought its use up I know some of their newer cars look to have a lot of bar toe in and the wide front maybe it's to keep drive without adding hike if your going up your wasting thrust to go forward, who knows some of the Team Zero cars use it to I know he did say they really cracked down on making sure on the touring level the right width LR wheel was being using that its a big advantage with drive in the slick there, food for thought maybe

[Matt49]

Most all the new rockets minus the black runs it standard, I haven't really looked at all the geometry to see why. Even Mark brought its use up I know some of their newer cars look to have a lot of bar toe in and the wide front maybe it's to keep drive without adding hike if your going up your wasting thrust to go forward, who knows some of the Team Zero cars use it to I know he did say they really cracked down on making sure on the touring level the right width LR wheel was being using that its a big advantage with drive in the slick there, food for thought maybe

Additional food for thought on the Team Zero part of this...
A few years ago I was in the pits at Florence and stopped to say hello to Bloomquist. Some wheels were laying out next to the car and I noticed the EXTREME offset of the LR wheel.
I said, "My God, what offset is that wheel?". His reply..."2 inches".

[DLM06]

In my experience adding a spacer to the LR does not add drive, wedge or weight to the LR. The spacer adds side bite and reduces wedge. Whenever a spacer is added to the LR you need to add a couple of turns to get the wedge back to what it was before the spacer. As far as the LR rim being closer to the ground when the car is jacked up, that is what I would expect since, if you have wedge in the car, the LR is going to be angled toward the ground. Adding the spacer gets it closer.

Adding the spacer and increasing the side bite would be felt until the car got totally straight.

[7uptruckracer]

It was my understanding they aren't allowed to do that anymore with the actual rim and tires from Mark but IF your local track doesn't check it to try it and see how it reacts to your car. Like anything I'm sure it's a package deal. If you can use that to make your car drive straighter off the corners and hook up better then you can take some upward thrust angle out elsewhere and if your not using all that thrust and upper bar angle to hike the car and create drive you can use it to push the car forwar,d I can see where it has its place. I don't pay attention to the LR much as far as any of the dynamic wedge. Your weight is transferring away from the LR until your getting back on the car the bars and shock package are doing all the work until you pick the throttle back up and weight starts to transfer back. Just my opinion its something I use when I want to tighten only exit on some of my cars.

[Dragoon55]

I hate to tell you this but adding a wheel spacer to the lr will NOT add drive. It will tighten entry and loosen exit. Sorry, but you have this backwards. 2" wheel spacer to LR tightens exit because it gives the LR more leverage on the polar moment of the car. Essentially you are giving the LR a longer handle to effect the car with. Also adding a 2" spacer or any spacer to the RF will tighten the car through out corner. On dry/slick we usually space LR & RF together on swingarm car for best result. On 4 link I think 2" LR would be just right for tightening exit, but you can try a 1" and see if thats all you need. Now in kart racing we did the reverse in the rear, but that is a whole nother kettle of fish.
Moving the lr wheel out does take weight off of it if no other adjustments are made. It also moves the center of the thrust generated by both rear tires to the left. The farther to the left that thrust is, the more the car wants to turn right. What wins out depends on quite a few factors.This guy knows, he just calls it thrust instead of leverage.

[crewchief32]

No I definitely don't have it backwards.