LF Spring Theory

[gotdirt]

So last week I had a 500 on the left front... We won the feature, but the car was tight on corner exit on the gas as soon as I would pick up the throttle...Sometimes I would drag the brake off the corner to keep the nose of the car down till I could drive the push out. I have always thought that a softer LF spring loosens the car off the corner and of course stiffer LF tightens off. So this weekend all I did was soften the LF to a 450. Everything else the same...Same track conditions...The car had a terrible throttle push all night. 10 times worse than the week we won?? It was undrivable. I could enter the corner perfect, have the car turned to come off, but as soon as I would pick up the throttle the car would take off to the wall...Should have changed it back, but I didn't. So my question is...Did I go the wrong way with this spring?

[CCHIEF]

Something else is going on. LF spring has little to no effect on corner exit handling.

[rakracing]

lf effects getting in a lot ,not much on exit ,may have let it get off the rf a little sooner try tying down the rf a bit more if its good in and thru the middle.

[a25rjr]

You have increased the dynamic wedge with the softer spring, esp if your lf is staying tied down.

[MBR Performance]

The more you soften the LF the more you will tighten exit. The days of saying it doesn't really effect exit are gone.

[fastford]

MBR is correct, what right front set up are you on?

[gotdirt]

MBR is correct, what right front set up are you on? 375 spring....100lb compression...rebound tied down all I can...800lbs

[Kromulous]

MBR, if it tightens exit, what does it affect on entry?

[MBR Performance]

It will free your entry. However it has another effect that the closer you match the front springs the better the car will turn in on its own. I like to keep dropping the LF spring until it makes the car to free on entry then step it back up 25lbs.

[Kromulous]

Thanks, looking for more adjustments in the slick than the usual.

Will give this a try.

[CCHIEF]

With that logic a 525-550 LF spring will help eliminate your throttle push! 50# less LF spring is not going to turn your racecar into a dump truck. Way Too little info to give any kind of responsible recommendation. I'd bet the track had more moisture in it, that tends to make these cars a tick (sarcasm) tighter.

[MBR Performance]

He was already throttle tight the weekend before and lowered the LF spring even more so yes 50 pound would make it worse and possibly make it drive like a dump truck

[CCHIEF]

The LF spring is not the go to adjustment for a tight car on exit. Give up what you got car, set,track and tires. Their is so much dynamic wedge in these cars when hiked up that 50# of spring... on the least loaded corner of the car (on exit) is not where you want to be adjusting FOR EXIT! Bringing the LR bars closer together @ frame would be a much more viable adjustment.

[MBR Performance]

Bad idea to move the bars

[CCHIEF]

Yes, you are right, a heavier LF spring is the go to adjustment for tight on the gas. (sarcasm)

[CCHIEF]

Tell us why a lr bar adjustment is a bad idea. (no sarcasm)

[MBR Performance]

First I never said that a LF spring change is the "go to" adjustment for throttle tight. Second changing the rod angle has to many other effects on the car. The better option would be to remove some LR drive which would help the throttle tight condition and a lose entry condition he should also have with being so throttle tight without affecting the roll steer of the car.

[fastford]

the left front spring is not as crucial on this posters car with the rt front set up he has, but, I've found it to be a lot more significant with a soft spring/bump stop set up on rt front where there is more loading on left front..

[gotdirt]

Thanks guys... Track conditions were the same.. Track might have been a little faster the week we won?? I was really just wanting to know if I went the wrong way with the LF... And looks and feels that I did...Ill change it back... Maybe drop the wedge down, trail the rr bars 2 turns...my 4bars are already set for the car to be free...

[MBR Performance]

If your entry wasn't bad I would leave the LF spring in there and just adjust the wedge. Don't throw to many things at it because you won't know what adjustment changed the car if it doesn't work

[Aces&Eights]

So last week I had a 500 on the left front... We won the feature, but the car was tight on corner exit on the gas as soon as I would pick up the throttle...Sometimes I would drag the brake off the corner to keep the nose of the car down till I could drive the push out. I have always thought that a softer LF spring loosens the car off the corner and of course stiffer LF tightens off. So this weekend all I did was soften the LF to a 450. Everything else the same...Same track conditions...The car had a terrible throttle push all night. 10 times worse than the week we won?? It was undrivable. I could enter the corner perfect, have the car turned to come off, but as soon as I would pick up the throttle the car would take off to the wall...Should have changed it back, but I didn't. So my question is...Did I go the wrong way with this spring?

Your messing with the wrong spring, but if changing the LF made entry and center better I'd leave it alone and look elsewhere.

[CCHIEF]

Thanks guys... Track conditions were the same.. Track might have been a little faster the week we won?? I was really just wanting to know if I went the wrong way with the LF... And looks and feels that I did...Ill change it back... Maybe drop the wedge down, trail the rr bars 2 turns...my 4bars are already set for the car to be free... I would expect it to be tighter on a faster track. A stopwatch is a good tool for judging if your up to speed with the best cars that night. One thing for sure is when your out front you can let the car go where it wants to, which is almost always faster than pinching it off somewhere(all them darn moving obstacles on the track!). When your leading those following need to make a better lap time than you to get past you....and/or steal your line (make you pinch off car). Congrats on your win, hope you get more. If I can be of assistance, feel free to ask.... I'm not trolling for customers. What year make and model of car do you have? Where do you race? If you have a travel limiter on the LR bar adjustments can benefit your deal.

[Aces&Eights]

Why not just shorten the travel limiter on LR a bit?

[MBR Performance]

You do it your way and I'll do it mine.

[RCJ]

Is the track you race on high banked or flat?A Real flat track where the l/f is wanting to unload vs. a high banked track where the l/f sees more compression, will make the car react different to the same change.A l/f change can effect how the car is rotated in the center.When you go to the throttle the car is not rotated enough to get a good line off the corner.

[Kromulous]

We tried the 50lb drop on the LF, 500 to a 450 and it did what was described. Car stayed square off, and drove straight off the corner better.

Side effect was, it loosened entry in 3 a touch, and he couldn't hardly hold it on his line in the feature. 1 and 2 was fine, but that end of the track is shaped different.

Anyway, good adjustment thou, may try with some rebound added to the 5th coil, to frim up exit just a touch.

[MBR Performance]

Can you describe the problem? Was it loose on entry on or off the throttle? Was the RR trying to wash out?

[Kromulous]

Off throttle, going into 3 at Florence Speedway (North South track) i know alot of you are familiar with it. I want to say the RR was washing out a little. He said he basicly let it slide up to the wall while dropping speed until it firmed up. Then could go.

250lb RR spring.

1 and 2 was good, to a tad tight, but could drive thru it.

Gonna try a LR stack this week i think, and use this adjustment again in the feature. Were trying to learn some trail braking too, which i think will solve it. That and some rebound on the 5th shock.

[JustAddDirt]

Off throttle, going into 3 at Florence Speedway (North South track) i know alot of you are familiar with it. I want to say the RR was washing out a little. He said he basicly let it slide up to the wall while dropping speed until it firmed up. Then could go.

250lb RR spring.

1 and 2 was good, to a tad tight, but could drive thru it.

Gonna try a LR stack this week i think, and use this adjustment again in the feature. Were trying to learn some trail braking too, which i think will solve it. That and some rebound on the 5th shock.

turn 1-2 had some brown dirt up top to catch you last weekend 6/18, I was experiencing the same issue with my modified
could not get into 3 as well as 1-2. had to slow down a lot more than usual because there was no cushion left to lean on. then middle off there was some good dirt left up top. 1-2 had cushion entering and threw center and went away off 2.

[mod88s]

Krom why are you going to a LR stack?

[Matt49]

I simply want to add something to this...3 and 4 at Florence almost always end up slicker than 1 and 2. The track is situated such that 3 and 4 are at the north end and 1 and 2 are at the south. Straights basically run due north/south. We live in the northern hemisphere so 3 and 4 take direct sun ALL day while 1 and 2 are sometimes in the shade (due to banking and wall). But I bet they water the track equally...but I digress....

[Kromulous]

I watched your feature Justadddirt, your car looked the same LOL. Bad loose into 3, will trail braking help that?

Florence is oddly shaped, front stretch is basically up a small grade, and 1 and 2 looks like a motorcycle berm turn, looks narrow, and uphill. Go down the back stretch and turn 3 and 4 is in like a big bowl, back stretch is slightly downhill as well. Been a few years since i raced around it, but that's how i remember it, you notice it alot more driving a race car around there.

I like the LF spring with the 450lb in there, so just gonna work on something else to help entry in 3, and it might just be a different line, or trail braking. Right now i am thinking some rebound in the 5th coil shock for the feature.

[Kromulous]

I got some INTEL on a LR Stack from a touring guy, said thats all they run ever. More hike, and easier to keep the car up all the way around the track. If you notice them guys keep the car up all the time. We still struggle with that at times. So thats why i am trying.

[JustAddDirt]

I watched your feature Justadddirt, your car looked the same LOL. Bad loose into 3, will trail braking help that?

Florence is oddly shaped, front stretch is basically up a small grade, and 1 and 2 looks like a motorcycle berm turn, looks narrow, and uphill. Go down the back stretch and turn 3 and 4 is in like a big bowl, back stretch is slightly downhill as well. Been a few years since i raced around it, but that's how i remember it, you notice it alot more driving a race car around there.

I like the LF spring with the 450lb in there, so just gonna work on something else to help entry in 3, and it might just be a different line, or trail braking. Right now i am thinking some rebound in the 5th coil shock for the feature.

yes trail braking will help, as well as straight line braking. ( also crew told me after race I was entering corner faster than anyone) so a slower entry may help, by backing corner up a bit. I thought I was slow into corner already.

I have a smaller RF caliper so trail braking my car can be a bit tricky, it is always wanting to lead into corner which can tend to cause a loose in condition. might change caliper out when at Florence because of the sharper corner entry angle there.

[Kromulous]

LOL well from what i notice the rest of the field is dragging anchors around the track when your out front in the high groove. But yes i agree with your crew, you dont loose much speed on entry.

He is trying to learn trail braking, but i try to keep the car easier to keep hiked up for him at Florence. Another reason for the stack LR i hope.