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Are Boss LCA's the same as GT?

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1
Just got the Boss, and I'm experiencing some axle tramp in the rear under high loads.
I think they put higher durometer bushings back there, but not sure about LCA's. How do I remedy axle tramp? This can rear it's ugly head at the track..

PS the car is bone stock, so it's not an issue of LCA angle.
 

unrealford

Mustang owner since 84
521
0
What's axel tramp?
If you meant hopping, you need to replace upper control arm. Roush and Steeda make some good ones.
 
1,022
97
Exp. Type
HPDE
Exp. Level
10-20 Years
Texas
Replacing the lowers also solves the axle hop problem. It did for me at least but I am still installing the Steeda adjustable 3rd link and installing the adjustable mount.
 
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Flyboygsxr said:
Replacing the lowers also solves the axle hop problem. It did for me at least but I am still installing the Steeda adjustable 3rd link and installing the adjustable mount.

Good to know and thanks for that info!
The track will be Mosport in Ontario. A smooth, and recently paved track.
Also Shannonville, a much lesser known track in Ontario. This one has some bumps out there.

And yes, "Axle tramp" = wheel hop. Not sure why that term stuck in my head...thought I had read it somewhere :)
What causes this phenomenon, and why do new LCA's resolve the issue? Just curious! I'm new to the solid axle stuff!
 
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unrealford said:
What's axel tramp?
If you meant hopping, you need to replace upper control arm. Roush and Steeda make some good ones.

Thanks for the info. When you suggest replacing the UCA, is it because our stock LCA's are already good pieces and that the remaining deflection is due to the UCA?
 

TMSBOSS

Spending my pension on car parts and track fees.
6,295
3,329
Exp. Type
HPDE
Exp. Level
5-10 Years
Illinois
My wheel hop issues went away when I upgraded the suspension.

FRPP LCAs along with FRPP relocation brackets, P Springs and FRPP Adjustable Pan Hard Bar. Hop is gone. Car hooks much better.
 

unrealford

Mustang owner since 84
521
0
Re: Re: Are Boss LCA's the same as GT?

boro92 said:
Thanks for the info. When you suggest replacing the UCA, is it because our stock LCA's are already good pieces and that the remaining deflection is due to the UCA?
Our factory Upper Control Arm has soft bushings designed to be efficient for track and to keep drive line noise down.
The aftermarket upper control arms are firmer reducing movement that causes hopping effect, but will induce more cabin noise.
I strictly drag race my car and the ONLY thing I changed was the UCA and I never get wheel hop even with drag radials and 1.65-1.69 60ft launches.
 

Justin

Save the dawn for your dishes!!!
Re: Re: Are Boss LCA's the same as GT?

unrealford said:
Our factory Upper Control Arm has soft bushings designed to be efficient for track and to keep drive line noise down.
The aftermarket upper control arms are firmer reducing movement that causes hopping effect, but will induce more cabin noise.
I strictly drag race my car and the ONLY thing I changed was the UCA and I never get wheel hop even with drag radials and 1.65-1.69 60ft launches.
I did the LCA's first on my boss. it didnt get rid of the wheel hop at all till I got the upper. the stock UCA is like jelly lol.
 

Senderofan

Having more fun than should be allowed..in my Boss
boro92 said:
Thanks for the info. When you suggest replacing the UCA, is it because our stock LCA's are already good pieces and that the remaining deflection is due to the UCA?

I think both the LCA's and the UCA are adequate for daily driving and a certain level of spirited driving. As Justin pointed out....the factory UCA has a very soft bushing. I was extremely surprised by this and the softness in the LCA's. My new UCA has a heim joint instead of the rubber bushing....others will have urethane. The heim joint is said to add to noise on perhaps some harshness to the ride because it's all metal. My upgraded LCA's with lowering brackets, lowering springs and UCA along with the other rear components make the rear of my Boss feel much more planted and very solid. All my other suspension components have urethane bushing ( LCA's, Swaybars ) and feel like they have a significantly less amount of deflection which makes the whole suspension seem crisper and provides more driver feedback.

You would probably be best served by replacing the LCA's and see if that solves your issue. It's not a difficult project. If, after that, your wheel hop hasn't been solved...or if you plan on lowering the suspension...I'd highly recommend upgrading the UCA and/or mount.

Good Luck,

wayne
 

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