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Kromulous
04-05-2016, 12:11 PM
We have been fighting a ill handling race car for the 1st couple races of the year and i wanted to ask if you have the LF droop travel limited to much will it make the car loose in and thru the middle?

We are fighting a loose entry / middle and not enough drive off, not matter what i change. He says the car wont firm up and go, its like he has to wait on it. Once it does get on the straight it goes but it he looses to much speed in the corner.

Also the car is shredding the rear tires, more so than usual.

Pretty much standard 4 bar set up, 225RR, 200 / 165 LR, 100lbs bite. 500 LF, 350 RF high rebound. 5th coil is 36" out with a 350lb spring and no preload.

Thanks for any help, Krom.

Matt49
04-05-2016, 12:58 PM
Limiting travel shouldn't cause what you are describing unless it is so severe that the driver is having to sling the car in to get it to turn because of no rear steer. Drivers have been known to do that and not say so and then complain about the car sliding too much.
What about your scale numbers? It almost sounds like you are high on left side weight or low on rear or a combination of the two. Spring rates, bar changes, and all the shock adjustments in the world won't help much if you've got 57% left side.

brett4
04-05-2016, 02:55 PM
what is a droop limiter????

Kromulous
04-05-2016, 02:59 PM
Same as a chain on the LR, it just limits how much the Left front tire can drop down.

Run one on the RR as well.

fastford
04-05-2016, 04:59 PM
ive never ran a limiter on lf frt, but it seems to me it could effect weight transfer to right rear, I would unhook it just to see what happens..jmo

Matt49
04-05-2016, 05:28 PM
Wow...I see now that the question was about LF limiter and my response was completely thinking about LR...

Limiting LF rebound travel I would think would not have any real effect on entry since it should be in compression. Could cause what fastford is describing from the center off though.

MasterSbilt_Racer
04-05-2016, 05:29 PM
We have been fighting a ill handling race car for the 1st couple races of the year and i wanted to ask if you have the LF droop travel limited to much will it make the car loose in and thru the middle?

We are fighting a loose entry / middle and not enough drive off, not matter what i change. He says the car wont firm up and go, its like he has to wait on it. Once it does get on the straight it goes but it he looses to much speed in the corner.

Also the car is shredding the rear tires, more so than usual.

Pretty much standard 4 bar set up, 225RR, 200 / 165 LR, 100lbs bite. 500 LF, 350 RF high rebound. 5th coil is 36" out with a 350lb spring and no preload.

Thanks for any help, Krom.

I have found that limiting the lf droop does remove some sidebite and seems to improve drive off as it slows/limits the transfer to the rr.

slmcrewchief99
04-05-2016, 06:26 PM
I totally agree with MBracer. When you tie down the left front it will improve the drive off plus it seems to help the car on entry. The car drives in extremely good. Yes there is a fine line on how high you can tie it up. At a certain point it will drive like a dump truck. If you take the cable loose completely it will free you up more so I wouldn't make that change. Pull it up just tight enough till its a pain to get the bolts out of the shock for a spring change to start. Run it and see if its better. Then tighten it up a little more if you can stand it. Personally I wouldn't go more than a 1/2 inch. Any more and we run into your dump truck problem. lol

Matt49
04-05-2016, 06:46 PM
What is being used for this that also allows for adjustability? My new MasterSbilt has a tab on the LF frame rail almost directly above the lower control arm and I assume that is what this is for.

billetbirdcage
04-05-2016, 10:08 PM
What is being used for this that also allows for adjustability? My new MasterSbilt has a tab on the LF frame rail almost directly above the lower control arm and I assume that is what this is for.

A simple round clamp that goes around the control arm with a non adjustable cable. With the clamp positioned on the lower arm directly below the cable bracket , just make the length of the cable you need for the longest drop you want. Then to reduce the drop just slide the clamp out board, thus limiting the travel.

A lot easier then messing with some sort of adjusting chain or length of tether

GRT62
04-06-2016, 09:32 AM
what would be a good starting point on tying the LF? ive heard a 1/2" before the spring unloads but was wondering what everyone else thought.

MasterSbilt_Racer
04-06-2016, 09:35 AM
what would be a good starting point on tying the LF? ive heard a 1/2" before the spring unloads but was wondering what everyone else thought.

Honestly, if you plan to do that and nothing else it is really going to depend on your car and setup. I have seen a difference in the car by simply shorening drop a half inch from letting the shock top out.

GRT62
04-06-2016, 10:18 AM
I added a lot valving on rebound to the LF shock the last time we rebuilt the shocks and it helped a lot with drive off so I was just wondering if I could get more by tying up the LF

MasterSbilt_Racer
04-06-2016, 11:28 AM
In theory, you could have enough slow speed damping that you lift the lf wheel before the shock has much a chance to extend. You would need data and or testing to answer your question for sure.

The cars are complex enough that the answer to most questions is "it depends". On the driver, track, setup, car attitude, etc, etc

RCJ
04-06-2016, 11:45 AM
To the loose problem,I would check the rear axle to see if it is bent.How much rear steer do you have?

money17
04-06-2016, 12:36 PM
Make sure im right. Start dropping lf till spring barely unloads and chain or 1inch extension on shock from ride height? Good starting point?

billetbirdcage
04-06-2016, 12:44 PM
Make sure im right. Start dropping lf till spring barely unloads and chain. Good starting point?

Personally if your wanting to try it and looking for a ball park starting spot on how much to change travel, I'd shorten the travel on the LF a 1/2" from where you are now (where the shock stops it). That won't be totally radical change and should give you an idea of what it does for you, unless the LF is staying down by it's self for the most part then you can go a more. Basically I'd shorten about a 1/2" from where you're seeing your rebound travel typically at on your cars approximate rebound travel if it isn't coming up all the way.

money17
04-06-2016, 01:21 PM
Thank you sir.

Kromulous
04-07-2016, 08:08 AM
My device basicly had it limited just about when the spring dis-engaged the shock collar.

I took it off all together, going to see what it does off, and then i will try what MB and Billet says, about a 1/2" before the shock tops out.

billetbirdcage
04-07-2016, 01:14 PM
My device basicly had it limited just about when the spring dis-engaged the shock collar.

I took it off all together, going to see what it does off, and then i will try what MB and Billet says, about a 1/2" before the shock tops out.

In case I wasn't clear, my post was to limit travel a 1/2" from what your getting if you wasn't tethering the LF at all and you was wanting to try it as money17 asked. Now with that being said: The actual point that you end up stopping it at will vary greatly between drivers, car, tracks, set ups, and etc.

You may end up anything from full droop the shock will allow to tethered almost at ride hieght, that's a huge range but there isn't a set dimension that works for everyone. Also keep in mind that the shorter you go, you may need to alter the car's set up to actually make use of it. It like anything has pluses and negatives for different situations.

Just wanted to be clear that what I posted wasn't being taken as that is the most general length that is used, just where I'd start and adjust from there and fix any issues that come up.

Also want to add that stopping it when the spring unloads which is fine, but not for comparative purposes. Even with the same brand of car, one may have a stiff LF and one may have a soft LF or have different wheel loads cause of left side weight or wedge, so one may extend 1" before unloading the spring (say stiff LF or low Left side % car) and the other car (soft LF or high left % car) may extend 2" to unload the spring from ride hieght. IMO it's better to look at travel from ride hieght and use that for comparison numbers, because obviously 1" to 2" is a big difference in tether length.

Kromulous
04-07-2016, 02:32 PM
Tops out may of been the wrong word, 1/2" from full droop or shock's max extension.

Currently were running high left-side % 54.5, and rear % is high as well, 55.5 or so. That's with 100 lbs of bite and a 500 lb LF spring.

We have a alot of rebound on the LF already, and the tether may be overkill not sure. I am interested to find out the full effects of it.

cjsracing
04-10-2016, 06:08 PM
So last night was my first race in a new Mastersbilt and I had the LF shock drop limited 1/2" from full drop.

Would this limiting on the LF cause the RR to wheel hop?

In the heat my crew said my RR was wheel hopping. In the Bmain about the half way point the car came to life and started working. While doing maintenance on the car today I discovered that the LF chain had broke and I am curious if that is when the car came to life and maybe the chain was causing issues before it broke.

billetbirdcage
04-10-2016, 06:51 PM
So last night was my first race in a new Mastersbilt and I had the LF shock drop limited 1/2" from full drop.

Would this limiting on the LF cause the RR to wheel hop?

In the heat my crew said my RR was wheel hopping. In the Bmain about the half way point the car came to life and started working. While doing maintenance on the car today I discovered that the LF chain had broke and I am curious if that is when the car came to life and maybe the chain was causing issues before it broke.

Yes, it can. That is the problem many are going to experience unless you know what your doing when you start limiting it a fair amount, however it usually doesn't show up with the small amount of limit you was doing but can happen.

fastford
04-11-2016, 10:00 AM
leave it off and go from there, jmo.....

racer2e
04-11-2016, 06:26 PM
Where can I buy the clamp to attach the tether to the lower control arm?

cjsracing
04-11-2016, 08:13 PM
racer2e 1" round weight bracket

billetbirdcage
04-11-2016, 09:01 PM
Where can I buy the clamp to attach the tether to the lower control arm?

google "split shaft collar" then just search the diameter you need for your lower control arm. Just weld a tab on it for the tether.

it even shows some Walmart carry them, so not hard to find.

racer2e
04-11-2016, 11:31 PM
Kent, I am so disappointed. I was picturing a trick Billet aluminum clamp with a double shear mount for the cable. Of course, sometimes the simplest solutions are the best.

zeroracing
04-12-2016, 10:12 AM
If it makes you feel better Kent would probably buy one, engrave a Taylormade logo in it and ship it to you for a couple hundred.

racer2e
04-12-2016, 12:39 PM
That is darn nice of him, but I am going to pass.

billetbirdcage
04-12-2016, 01:28 PM
LOL, surely that trick billet mount would make the car faster then a new tire. (sarcasm)

Kromulous
04-18-2016, 12:42 PM
Took the limiting device off, and the car responded well. Finally took off in feature.

I made other changes, so i may go back and revisit the limiter later but for now, its off.

MasterSbilt_Racer
04-18-2016, 01:13 PM
Took the limiting device off, and the car responded well. Finally took off in feature.

I made other changes, so i may go back and revisit the limiter later but for now, its off.

The car looked pretty good!

Kromulous
04-18-2016, 03:34 PM
Thanks MB, you still helping Joe this year?

He was working his way up thru there sat too.

MasterSbilt_Racer
04-18-2016, 04:18 PM
Thanks MB, you still helping Joe this year?

He was working his way up thru there sat too.

Yeah. That was a new car. First time on the track. We were pretty ill-prepared to race, but it was encouraging.

Kromulous
04-19-2016, 08:04 AM
What kinda car did he get? Looked pretty good for 1st time out really, he was working it up towards the top ten there. Seems like he got the short end on the draw and heat race, that happens.

MasterSbilt_Racer
04-19-2016, 08:23 AM
What kinda car did he get? Looked pretty good for 1st time out really, he was working it up towards the top ten there. Seems like he got the short end on the draw and heat race, that happens.

It is a Smackdown frankensteined into a Gen X by the guys in Crothersville.