Installing J&M LCA's..

[Trav4011]

My car pulls both front 18's on radials. I don't have a traction problem bud. I was clearly referring to the relocation brackets in the statement I quoted. I feel that the relocation brackets are dangerous on the highway. You get zero weight transfer and no squat which causes the tires to unload when not on a prepped track, even at 70 mph. When I launch I get front lift and rear lift which I don't think is good.

This kinda makes sense.. which is why I don't think I'm going to install them. There's no reason to.. I've eliminated wheel hop, and I'll focus on tires/springs/shocks to address improvements in traction.

Travis

 

[KJGT]

I forgot to mention that I have the Roush anti wheel hop kit (UCA) installed as well..

However, when I installed the Roush UCA, it didn't do much of anything to stop the wheel hop.

Travis

Lot of people swear the Roush UCA alone fixed the problem so who knows lol.

Its funny because because LS1 4th gens both hopped equally as bad, auto or manual, fix was torque arm bushings and LCAs. But of course there were guys that claimed no hop on stock cars.

I am waiting on the relocation brackets myself, the Roush springs did lower it a bit but it worked out with the extra blower weight in the front that dropped the front about a half inch. I may put the arms because they are here but its kind of hard to argue with a 1.59 on the stock LCAs lol.

 

[Trav4011]

Yeah, I've seen that too.. I was pissed when it didn't fix the problem on mine! lol..

How tall of a DR/slick are you running? I think the fact that I'm running on a short sidewall (26") might have something to do with it, too. On a taller tire, the sidewall absorbs more shock.

Travis

 

[KJGT]

Yeah, I've seen that too.. I was pissed when it didn't fix the problem on mine! lol..

How tall of a DR/slick are you running? I think the fact that I'm running on a short sidewall (26") might have something to do with it, too. On a taller tire, the sidewall absorbs more shock.

Travis

I am using a 265/40/18 M/T radial on the stock wheels, video in the drag racing section.

Its supposed to be 26.6" tall but I'd be surprised if it was over 26 inches, they are short.

Absolutely, a 26-28" fifteen inch wheel bias ET street, hoosier QTP or real slicks will eliminate a lof of hop because the tire absorbs a lot of it.

 

[Trav4011]

Cool.. so you're not any taller than mine. I've got 275/40-17's, and they measure around 26".

 

[KJGT]

Cool.. so you're not any taller than mine. I've got 275/40-17's, and they measure around 26".

You have a little more sidewall on a 17, still not much sidewall though. The 18" M/T really surprised me how well it hooked, it looks kinda goofy though since its on a stock 8" wheel and shorter then the front tires so i dont like street driving it with them.

Going to try the repro 10" wide rears and 305/40/18 Nittos (27.7" tall) for street driving and hope they do OK at a decent track. If not I'll use the M/Ts at the track..

 

[35anngt]

I have the ford racing LCA's. These any good?


not to thread jack. they just look so similiar to stock.

 

[RazorbackMustang]

Well, based on a couple comments here I'm going to leave the brackets off and try just the LCAs. Weather permitting I'll hit the track on the 19th and report back.

 

[908ssp]

I use the J&M LCA without relocation brackets and I am really happy. Now I am not a drag racer but like they way they stabilize the rear on the race course and street when putting the pedal down. the J&M are better suited then most as they have less binding when leaning or hitting bumps.

 

[JerryC]

My car pulls both front 18's on radials. I don't have a traction problem bud. I was clearly referring to the relocation brackets in the statement I quoted. I feel that the relocation brackets are dangerous on the highway. You get zero weight transfer and no squat which causes the tires to unload when not on a prepped track, even at 70 mph. When I launch I get front lift and rear lift which I don't think is good.

The rear lifts because the LCA's are pushing down on the rear axle. That's caused by the rotation of the rear axle, which tries to push the rear axle away from the chassis. Since the ground wont go down the car goes up. That is what you want.

 

[SlowA$$5.0]

The rear lifts because the LCA's are pushing down on the rear axle. That's caused by the rotation of the rear axle, which tries to push the rear axle away from the chassis. Since the ground wont go down the car goes up. That is what you want.

That is what you want in some situations. However, in my situation it hurts more than if helps. Thanks for your input, but I have track times to prove that they hurt more than they help. You don't want rear lift and front lift with radials and a manual. If you never transfer any weight to the tires, how do you expect it to hook to its full potential?

 

[JerryC]

That is what you want in some situations. However, in my situation it hurts more than if helps. Thanks for your input, but I have track times to prove that they hurt more than they help. You don't want rear lift and front lift with radials and a manual. If you never transfer any weight to the tires, how do you expect it to hook to its full potential?

I'm not suspension expert, but I'll give this a shot. I'm a drag race minded guy, so keep that in mind.

Ideally you don't want weight transfer or lift or drop. You want the car to go forward, any other motion is wasting time. In the real world that's going to be impossible to do.

So when the torque of the launch affects the car it wants to do a few things, rotate the rear (pinion goes up) and twist the mass of the car in direction the engine rotates. Again, all that wastes time since that energy is not being used to move the car forward.

Squat is when the car drops down in the rear over the rear tires, when this happens you are wasting energy that could be used to go forward. It also is an indication that your rear suspension is allowing the weight of the car to take up suspension travel. This does have the effect of putting more weight over the tires, but it's not the best way. As you travel forward the rear end is going to unload and rise and you may lose traction again since the weight transfer you relied upon is no longer there. The rear dropping drastically also effects front end geometry, that's not a big deal in drag racing, but I would think in turns it would be.

When the rear geometry is setup correctly, the twising of the rear uses the LCa's to push up on the chassis, forcing the rear towards the ground. If the tires hold traction the car will rise some. The front will lift as well affecting weight transfer, if you have enough traction and power you'll get the fronts off the ground. You can limit the rise of the of the car through the suspension, but on a street/strip car that will affect how the car rides. This configuration keeps pushing the rear toward the ground as long as you have power applied.

I hope that helps.

 

[S197 GT]

^ He gets it.