Too Tigh On Entry wont rotate

[Dirtracer18]

i have a 06 blue front end rocket with the wide rf. no matter what the track condition is the car will not rotate on entry it just plows the front end. LF 550 RF 275 LR 200 RR225 Left 54.4% Rear 51.8% Cross 54.4%. Scale numbers Lf 601 rf 602 LR760 rr 537Short ltb in the 3rd hole. Llb 4th hole. Rtb middle hole. Rlb 2nd hole. Bars are standard lengths for rocket. J bar is 9 3/4 on the frame and bottom of pinion been in the middle also still no difference. Running a steel headed motor

[96racing]

Where's the j bar? Mine acts that way when it doesn't have enough angle. Rear percentage seems quite low too.

[Dirtracer18]

J bar is 9 3/4 on frame and in the bottom of the pinion

[MasterSbilt_Racer]

Any bump stops? Is the cross member still in the original place? You are likely bottoming out and that is why it pushes. Put a 400# in the rf, rescale, and see if it turns.

[Dirtracer18]

Yes have a bumpstop on the right front. Does not have a raised crossmember. I don't feel it bottom out. Haven't been on a 400 rf but have been on a 350 and 375.

[7uptruckracer]

i have a 06 blue front end rocket with the wide rf. no matter what the track condition is the car will not rotate on entry it just plows the front end. LF 550 RF 275 LR 200 RR225 Left 54.4% Rear 51.8% Cross 54.4%. Scale numbers Lf 601 rf 602 LR760 rr 537Short ltb in the 3rd hole. Llb 4th hole. Rtb middle hole. Rlb 2nd hole. Bars are standard lengths for rocket. J bar is 9 3/4 on the frame and bottom of pinion been in the middle also still no difference. Running a steel headed motor

You have 223lbs of LR Bite. That’s needs to be around 120. All that bite if you are driving in on the far that’s gonna make it push. 450 Left Front spring, 325 RF. 8 3/4 jbar middle pinion, 53.5 rear, reset all your front end and get rid of the short LRU just as basics

[CCHIEF]

Rear too light panhard bar too high @ frame rf spring too soft rr way to light...too much bite get back to a normal loose baseline with correct %...you need some lead toward the rr

[Aggressor]

go to a 250 rr

[JustAddDirt]

go to a 250 rr

That will tighten entry

[billetbirdcage]

That will tighten entry

Up to about 2 years ago, I'd whole heartily agree with that but now: There are exceptions to that and quite a few actually.

1 If you're only changing the spring and maybe resetting the coilover back to the same ride hieght, then yes most of the time that's what you're going to get.

2. However if your changing the spring and adjusting the ride height load number, then you may not get the same effect. Meaning I have a 225# spring with a static ride hieght load number of say 350# and typically traveling 2.5" from ride height. So that makes my static load 350# and my 2.5" load at 912.5, but say I do this: 250 spring with a 287.5# load number, my 2.5" number is the same 912.5#. I'll pretty much guarantee that it don't handle the same. I not only changed the ride hieght therefore right side bar angles and wheel base but also the aero on the car as well as the wedge numbers.

Like I'd said I'd agree with it for the most part but you have to take into context some of these other things because we are doing stuff completely different now and looking at things in other ways and it throws a bunch of exceptions into the old rules.

Just want to say I'd agree with justadddirt I probably wouldn't stiffen the spring in his case, but you have to know how he was going to change it. I'm going to go out on a limb and guess that I believe the OP is likely racing on a fairly flat track.

[a25rjr]

Up to about 2 years ago, I'd whole heartily agree with that but now: There are exceptions to that and quite a few actually.

1 If you're only changing the spring and maybe resetting the coilover back to the same ride hieght, then yes most of the time that's what you're going to get.

2. However if your changing the spring and adjusting the ride height load number, then you may not get the same effect. Meaning I have a 225# spring with a static ride hieght load number of say 350# and typically traveling 2.5" from ride height. So that makes my static load 350# and my 2.5" load at 912.5, but say I do this: 250 spring with a 287.5# load number, my 2.5" number is the same 912.5#. I'll pretty much guarantee that it don't handle the same. I not only changed the ride hieght therefore right side bar angles and wheel base but also the aero on the car as well as the wedge numbers.

Like I'd said I'd agree with it for the most part but you have to take into context some of these other things because we are doing stuff completely different now and looking at things in other ways and it throws a bunch of exceptions into the old rules.

Just want to say I'd agree with justadddirt I probably wouldn't stiffen the spring in his case, but you have to know how he was going to change it. I'm going to go out on a limb and guess that I believe the OP is likely racing on a fairly flat track.

Do you think most people re-set their ride heights after changing springs? I know that I never changed a spring at the track, that I had already tried it on the scales at the shop. Usually, I had a spare already set but not every time!

[billetbirdcage]

Do you think most people re-set their ride heights after changing springs? I know that I never changed a spring at the track, that I had already tried it on the scales at the shop. Usually, I had a spare already set but not every time!

Sure most do, but what I'm getting at it completely isn't the same thing.

My example above: 225 to 250 with resetting coilover nut (just for shear info here to adjust it back to the same ride height you are talking .150" of an adjustment up on the coil over nut to get it correct assuming both springs are indeed 225 and 250 and linear).

225 = #350 static load #912.5 dynamic
250 = #350 static load #975 dynamic

Mostly you changed the dynamic loads from ride height down and most likely lessened the travel on the RR.

If you did what I said with replacing the 225 with a 250 but altered the static load

250 = #287.5 static and #912.5 dynamic

I took some liberties here cause obviously these changes don't exactly mean the RR is still going to go to that imaginary 2.5" dynamic travel

All three of these are going to react differently which was the point I was making, the rate of the spring is only one factor. Again not saying anyone is wrong but depending on what you do, you are likely to get a different reaction.

[Matt49]

Is there a particular scenario where I would actually want to change the RR spring and change the static load on that spring? Would the goal be just to free entry a little while maintaining the tightness from center off under full load? But then playing devil's advocate here...aren't there easier, simpler, or better ways to achieve that?

[MasterSbilt_Racer]

Is there a particular scenario where I would actually want to change the RR spring and change the static load on that spring? Would the goal be just to free entry a little while maintaining the tightness from center off under full load? But then playing devil's advocate here...aren't there easier, simpler, or better ways to achieve that?

Ask the XR1 guys who's RR corner keeps getting lower as the night goes on and they keep carrying spring rubbers to the rr.

[7uptruckracer]

I don't personally know anyone on XR1 who are changing things there anymore, the other Rockets definitely though. I dunno what the difference is on why one and not the other. My friends running and winning on XR1 still aren't chanfing anything bc Rocket told them not too lol. Now that being said the only change I was told was recommended was being told to take rounds out the RR as an adjustment. That and the stagger. Which Maybe another topic for discussion the low stagger makes alot more sense for driving a car straight ahead then the 4" we have always just stuck with

[DEKconsulting]

Get ur lr bite down to any where between 80 to 120lbs. What is ur load numbers on ur rf with the 275 3in an 4in? Jbar needs to be 8.75 on frame and level with pinion. Right side bars in 3rd hole left side top in middle and 5th on the bottom. Might want to ho to 450 lf too. How is track condition smooth and tacky or rough and tacky. This should get u pretty neutraul in any condition

[Matt49]

Ask the XR1 guys who's RR corner keeps getting lower as the night goes on and they keep carrying spring rubbers to the rr.

Kind of makes since. Take rounds out of RR to decrease static load. Add rubbers to increase dynamic load. This would free entry and tighten middle (take a set) and then the lower RR bar angles due to ride height change should in theory make it drive harder off the LR getting off the corner.
We just keep coming up with more and more reasons to buy a spring smasher, don't we? I've been putting it off too long. Can't get good info from anybody (even those willing to help) on RF bump stops without giving them all these load numbers first and not just on RF.

[MasterSbilt_Racer]

Kind of makes since. Take rounds out of RR to decrease static load. Add rubbers to increase dynamic load. This would free entry and tighten middle (take a set) and then the lower RR bar angles due to ride height change should in theory make it drive harder off the LR getting off the corner.
We just keep coming up with more and more reasons to buy a spring smasher, don't we? I've been putting it off too long. Can't get good info from anybody (even those willing to help) on RF bump stops without giving them all these load numbers first and not just on RF.

Yeah. I got along real good for a long time with no smasher. (Just doing the math myself.) Actually got messed up this year the first time I tried to use other people's numbers and a smasher. But, I think I need one at this point.

[fastford]

I don't personally know anyone on XR1 who are changing things there anymore, the other Rockets definitely though. I dunno what the difference is on why one and not the other. My friends running and winning on XR1 still aren't chanfing anything bc Rocket told them not too lol. Now that being said the only change I was told was recommended was being told to take rounds out the RR as an adjustment. That and the stagger. Which Maybe another topic for discussion the low stagger makes alot more sense for driving a car straight ahead then the 4" we have always just stuck with

saw a track record set with less than 1 inch of stagger this year , with the rear steer thats achieved now days , less is needed to turn , plus strait away speed is usually gained.....by the way , there was a thread on here a while back about running two 29s on rear , if im not mistaken , thats what he was on....

[fastford]

Kind of makes since. Take rounds out of RR to decrease static load. Add rubbers to increase dynamic load. This would free entry and tighten middle (take a set) and then the lower RR bar angles due to ride height change should in theory make it drive harder off the LR getting off the corner.
We just keep coming up with more and more reasons to buy a spring smasher, don't we? I've been putting it off too long. Can't get good info from anybody (even those willing to help) on RF bump stops without giving them all these load numbers first and not just on RF.

that does make good since , and kinda simplifies things some......

[billetbirdcage]

We just keep coming up with more and more reasons to buy a spring smasher, don't we? I've been putting it off too long. Can't get good info from anybody (even those willing to help) on RF bump stops without giving them all these load numbers first and not just on RF.

Like MB said you can do the math and get most of the info you need, it's just slower. Now setting or adjusting to pin to pin measurements without one takes a lot more steps and is way way slower then just using a cruncher. Before we had them, even with bump stops if you have the graphs on them I could take someones 375 spring off that was traveling max of 4.125" and change it to say a 250 with a bump stop and calculate it with math and throw it on the car and usually get within a 1/8" of travel most times.

The cruncher makes life a lot faster and easier but can be done without one. It saves a lot of trips back and forth to the car (depending on what your doing) and a lot more accurate.

[a25rjr]

Like MB said you can do the math and get most of the info you need, it's just slower. Now setting or adjusting to pin to pin measurements without one takes a lot more steps and is way way slower then just using a cruncher. Before we had them, even with bump stops if you have the graphs on them I could take someones 375 spring off that was traveling max of 4.125" and change it to say a 250 with a bump stop and calculate it with math and throw it on the car and usually get within a 1/8" of travel most times.

The cruncher makes life a lot faster and easier but can be done without one. It saves a lot of trips back and forth to the car (depending on what your doing) and a lot more accurate.

So my socket on the jack under the rearend is antiquated now! :)

[Matt49]

saw a track record set with less than 1 inch of stagger this year , with the rear steer thats achieved now days , less is needed to turn , plus strait away speed is usually gained.....by the way , there was a thread on here a while back about running two 29s on rear , if im not mistaken , thats what he was on....

Agree on the less stagger for sure with the amount of rear steer we have. You really only need enough stagger to keep the tires from "scrubbing" too much in the turns. But any amount of scrubbing you eliminate in the corners gets picked back up on the straights.
I think less that traditionally accepted stagger also puts optimal camber in the rear tires. Just look at the tire wear pattern that you get when running 4 inches or more of stagger. That can't be good or at least I see room for improvement.

[fastford]

the only thing is some times that stagger does create camber in the rt rear that is beneficial , maybe its time to look at cambered axle tubes again .