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MG MGB Technical - negative camber wishbone question?

Does anyone know the added length (in inches or mm's) that the negative wishbone arms are extended? Actually, if I knew in degrees, I could do the math. has anyone ever considerd making a kit to allow for adjustable camber and caster? It seems like it would be a relatively easy venture.
Thanks in advance.
Jeff Schlemmer

Jeff,

Frontline front has camber adjustment, midgets use top trunnion.

For Castor and Camber Hoyle front available from Doug jackson in US.

Depends on how much neg.

Paul
Paul

Jackson (mgbmga.com) sell an offset nylatron top bush, but it only alows about 1/2 dgree camber adjsutment.

The only way (in my opinion) to correctly adjust caster on a B is wedge shims inder the front crossmember or matching wedges and slots under the shouch and lower A-arm pivot mount- otherwise you preload the pivots and bind the front suspension.


That being said, I'm modifying my front crossmember so the shock mount can be moved in and out for camber adjustment,

The real downside of modern tires on the B is the lack of negaive camber gain in roll- what this car REALLY needs is a long kingpin that you can shim to get ride height you want and good negative camber gain in roll.

Lots of static negative camber is less than the best way to get good handling

Most tires want about 1/2° negative static and generate maximum grip at about 1° negative (from Race Car Vehicle Dynamics, Paul van Valkenburg, IIRC, but it's been a long time).

just a few thoughts
Greg Fast

Bill Guzman has recently started offering these, I believe.

His website is:

www.calssicconversionseng.com

Regards,

Brian
Brian Corrigan

Thanks Greg and Brian. I believe I got the info I was looking for from a picture on Bill Guzmann's website. I'll be looking forward to more input on the "ideal" alignment specs for this car. Wouldn't an adjustable lower control arm pivot give the best camber adjustment? I also like the idea of a cam bolt adjustment at the lower kingpin pivot. It doesn't seem like caster is a problem with these cars, but couldn't it be adjusted with shims between the kingpin and lower control arms? At least to a limited extent. Modifying the control arms for more shim capabilities shouldn't be that difficult, and boxing inthe ends of the control arms should strengthen them enough to prevent any flex.

Jeff Schlemmer

Jeff- Having just completed the rebuild of the B frontend and installing the neg-cambers, I ran out to the shop and measured the 2. The neg cambers are 3/16 longer on the trunnion mount holes. Seems like a guy could spot a plate and redrill an original and get the same effect for lots less money. Vic
vem myers

Vic, THANKS!!! That's the info I was looking for. I could guestimate from a picture I found on Bill Guzmann's website, and figured from his modifications it would be between 3/16 and 5/16". (His were adjustable 1-2 degrees.) The way I see it, an hour of my time still isn't worth $80.

Back I go to the world of panel-beating. My doors will fit right if it kills me!!!
Jeff Schlemmer

Jeff- Couldn't agree more with your economics. I will confess spending 1-2 hours in the 70's rebuilding light switches or fan motors. Now I can't justify the time with the current dollar cost and availability of all these little things. FWIW, I have the front end complete on the 1980 rebuild, with the neg camber wishbones, retained the 9/16 sway ( per advice earlier from a poster claiming the 3/4 bar way-amplified the understeer), reset the tow 1/16 ( one full thread it turned out), and set the bearings per Blackwood's persuasive debate earlier. With new boots, I refilled the rack with Redline and all in all, it honestly felt like power steering when I went out for the settle-in run before final trunnion nut tightening. I sand blasted everything and used a POR-like impersonator on each piece and the bare cross and wells. I used a Wagner power sprayer for the Waxoyl later as the included "pressure tip" supplied in the starter kit was just laughable and 100% unuseable ( why do they do that...Why does Peco use that goofy red paint?) As far as bang for btu invested, this has been one of the most satisfying projects to date on "This Old Car", and the frontward gams are so pretty now. Finally, I fitted rebuilt original Armstrong Dampers, having previously converted the other cars to the 1986-1988 Dodge Gabriels, and found the ride noticeably better with the stock shock. So there it is, my hands on testimonial, finally. All you guys were right afterall: The original setup is hard to beat
vem myers

Just want to comment a litle to vem:

I'm not certain I buy the concept that a larger front bar increases understeer as a global statement.

One feature of the B is that as the car rolls in a turn, the inner lower pivot is pukked inboard and the upper inner pivet is pushed outboard, in addition to suspension compression. This puts the outboard wheel in a positive camber situation, with less grip.

Depending on tire, additional front grip (reduced understeer) could be achieved with a larger front bar that reduces front body roll.

Flies in the face of all the published 'fixes', but if you think about it it makes sense. The car was designed for low grip tires- put some stickies on and you get huge front body roll. I know, I have pictures of the basically stock (revalved levers, 7/8 front bar, no rear bar, shorter stiffer springs (forgot the rate)) race car with probably 5° positive camber in a tight turn out at the club track at Las Vegas.

Best thing to do is to talk to others, think about what they say, then embrace or reject ideas based on testing.

Added a 5/8" rear bar, car got a little loose. Up to a 1" front bar, 5/8 adjustable rear bar- and the motor blew up. I'll have more information next summer
Greg Fast

Greg,

Taking this a step further assuming not RB ride height.

The neg improves front end grip which is further improved by controlling camber change with either front spring increase or arb but now with increased weight transfer at front reducing front end grip but gaining rear grip. So the improved grip at front has been transferred to rear where needed.

Then put on a rear bar that does the opposite and lifts inner rear driving wheel and gives snap oversteer ie car gets a liitle loose.

An alternative to rear arb is Frontlines traction control link, which locates rear axle but allows springs to work and you can adjust roll axis.

Certainly agree it should be based on testing and vem is happy with 9/16ths, and will await your next summer testing.

Paul
Paul Wiley

Well actually, retaining the 9/16 front, going the neg-camber wish, and shodding with 195/60, she seems to be understeering more than the stock setting before I started fooling around. However, with the lowering, rebuild ( both front and rear as of today) the car is transformed 95% of driving time. I notice the "quiver" understeer at very high speed cornering only and find if I relax the turn and slow a bit all is well.
vem myers

This thread was discussed between 20/11/2003 and 01/12/2003

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