J Man jason adkins NW OH (202 posts) Registered: 01/21/2009 08:49PM Main British Car: '61 Morris Minor panel, '70 MGB GT, '74 MGB GT MGB 1.8, unsure yet on the GTs |
Negative camber lower control arms
I found someone selling a set of these. What would their purpose be? Advantages to running them? Would they cause wheel fitment issues? Thanks
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BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6470 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Negative camber lower control arms
Might be helpful if you cut the springs to lower the car.
Jim |
mgb260 Jim Nichols Sequim,WA (2463 posts) Registered: 02/29/2008 08:29PM Main British Car: 1973 MGB roadster 260 Ford V8 |
Re: Negative camber lower control arms
They are about 1/8" longer than stock MGB lower arms and give about 2 degrees negative camber. Front tires will wear a little more inside. Help cornering a little.
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Moderator Curtis Jacobson Portland Oregon (4577 posts) Registered: 10/12/2007 02:16AM Main British Car: 71 MGBGT, Buick 215 |
Re: Negative camber lower control arms
Moss has sold these for MGB for as long as I can remember.
For the MGB, they look exactly like regular lower control arms - just slightly longer. (We're talking about just the two c-channels which bolt to either side of the spring pan. The spring pan doesn't change.) Yes, they alter cornering (for the better) but they also effect braking (slightly for the worse, at least in a straight line.) What do they do exactly? In simplified terms... as the car's body tilts sideways while negotiating a turn, and as weight load shifts from the inside front tire's contact patch to the outside front tire, and as the outside suspension compresses, and as a function of the unequal length and non-parallel arrangement of upper versus lower control arms, the wheels and tires lean over a little bit. That's called "camber change." These arms change the starting point for that camber change behavior, and subsequently the ending point. Again, in very simplified terms... you'd like the outside tire to be perfectly perpendicular to the road at all times. That's not feasible. This product might help your tires achieve perpendicularity in hard turns. |
J Man jason adkins NW OH (202 posts) Registered: 01/21/2009 08:49PM Main British Car: '61 Morris Minor panel, '70 MGB GT, '74 MGB GT MGB 1.8, unsure yet on the GTs |
Re: Negative camber lower control arms
I guess I forgot to mention what vehicle these were for but you guys figured it out.
Would these be good for a daily street driven vehicle (or even needed) or more suited for a race application? |
MGBV8 Carl Floyd Kingsport, TN (4513 posts) Registered: 10/23/2007 11:32PM Main British Car: 1979 MGB Buick 215 |
Re: Negative camber lower control arms
They are totally unnecessary (some would say undesirable) for a daily driver.
Disclaimer: I still run the stock lower A-arms on my street/autocross/track day MG. It seems to holds its own just fine without the additional negative camber. |
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ex-tyke Graham Creswick Chatham, Ontario, Canada (1165 posts) Registered: 10/25/2007 11:17AM Main British Car: 1976 MGB Ford 302 |
Re: Negative camber lower control arms
Quote: I dunno, Carl....the NASCAR boys take camber to the max. |
Moderator Curtis Jacobson Portland Oregon (4577 posts) Registered: 10/12/2007 02:16AM Main British Car: 71 MGBGT, Buick 215 |
Re: Negative camber lower control arms
In racecar set-up, one lap-time reduction strategy is to maximize exit speed from whatever corner comes immediately before the longest straight. How tight is that corner? How much banking? A racer might add or reduce static camber compared to the previous weekend's set-up to optimize that one corner's exit speed thus providing faster speed all the way down the main straight.
If the banking is different at Daytona than it is at Martinsville, for example, it makes sense that NASCAR boys probably adjust camber accordingly. One screwy up thing about MGBs is that swapping control arms is a gross adjustment. I wish someone would offer stock-length control arms except with a nifty adjustment cam mechanism at one end to facilitate fine tuning. (But maybe the adjustment should be made at the upper end. No?) Here's the important point: a racecar can't be optimized for every corner on a road racing circuit, and a car certainly can't be optimized for every corner on real world roads. You have to choose a compromise setting. (I use stock lower control arms.) |
MGBV8 Carl Floyd Kingsport, TN (4513 posts) Registered: 10/23/2007 11:32PM Main British Car: 1979 MGB Buick 215 |
Re: Negative camber lower control arms
Now Graham, somewhere in that sentence I did say daily driver.
Quote: Bill Guzman used to sell something like that. |
BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6470 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Negative camber lower control arms
So, maybe it would be helpful for something like a car that had been lowered by using shorter springs?
Jim |
Moderator Curtis Jacobson Portland Oregon (4577 posts) Registered: 10/12/2007 02:16AM Main British Car: 71 MGBGT, Buick 215 |
Re: Negative camber lower control arms
Helpful in what way?
The main negative side effect of lowering a car by fitting shorter or shortened springs is that it typically shifts the operating range of the suspension from a zone of relatively little bump steer into one where bump steer is more pronounced. Camber shouldn't significantly effect bump steer. Why do alignment shops check and adjust camber on other cars besides MGB? My perception is that suspensions and frames tend to get tweaked on potholes and/or in minor accidents. I suspect a more fully adjustable suspension might be brought back to factory spec with fewer replaced parts. |
BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6470 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Negative camber lower control arms
I was thinking that the camber change at static ride height might be brought back closer to spec that way. Since the bottom pulls in under compression a longer arm would move it back out. But it might be too much.
Anyway, drop spindles would be a better way to lower the car. Jim |
roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Negative camber lower control arms
I suspect a lot of oem designs have "some" degree of bump steer, much like different akerman amounts. Perhaps a good place to start is minimizing the bump steer ? Why not run air bags ? You get static ride height where you want it ,and tunable rising, spring rates. Seems like moving the uca, inner pivots, up/down should help in fine tuning the camber curve ? Chees, roverman.
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BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6470 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Negative camber lower control arms
About four of us have tried air bags with varying success in the MGB. The biggest problem is finding a 4" diameter bag which nobody seems to make. The 4-1/2" ones are a little tight and may chafe.
Jim |
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roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Negative camber lower control arms, bags ?
Jim and clan, might want to peep, "AirBaggit.com". At least 2 lengths of 4" dia. bags,(double and triple convolute), rated at 1k lbs. ea. At least 2 kinds of 4" dia air shocks rated at 1k lbs ea. Not an endorsement. I bought my "Healey" bags/etc., from them. Good Luck, roverman.
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BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6470 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Negative camber lower control arms
I know it says 4" on the description but they really are closer to 4-1/2. With those bags it takes a fair amount of work and even more good luck to get adequate clearance we've found. If they were just 1/4" smaller it would be ideal.
Jim |
roverman Art Gertz Winchester, CA. (3188 posts) Registered: 04/24/2009 11:02AM Main British Car: 74' Jensen Healy, 79 Huff. GT 1, 74 MGB Lotus 907,2L |
Re: Negative camber lower control arms, bags ?
Clan, First bag listed, on their site #800, 3.5" dia. 150 max psi, 1,500 lbs/axle, 6"-10" height, cost $39. ea. Onward, roverman.
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BlownMGB-V8 Jim Blackwood 9406 Gunpowder Rd., Florence, KY 41042 (6470 posts) Registered: 10/23/2007 12:59PM Main British Car: 1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS |
Re: Negative camber lower control arms
Haven't looked at that one, almost certain to be too long. Might buy one or two and try them. I already have too many "spares" lying around, it's somebody else's turn.
Jim Edited 1 time(s). Last edit at 01/04/2013 03:49PM by BlownMGB-V8. |
MGBV8 Carl Floyd Kingsport, TN (4513 posts) Registered: 10/23/2007 11:32PM Main British Car: 1979 MGB Buick 215 |
Re: Negative camber lower control arms
Bump steer? I think too much is made of the little bit of bump steer caused by lowering an MGB with shorter springs.
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