FiA MGB Suspension Modifications; Adjustable Front Lever Arm Dampers & Rear Axle Correction Wedge

Some further modifications to my FiA MGB using parts supplied by AJ Barnard. I’ve always liked the idea of having some camber adjustment on the front of the car and these specially made dampers seem a great way to achieve this. I have tried the eccentric trunnion bushes in the past but they did not seem to work; they would turn as the suspension moved though it’s travel and change the camber on their own. ajbengineering.com/products/c...
Another part I am very excited about is the adjustable valve from the front lever arm shocks. I’ve had the adjustable dampers on the rear since I started racing and they are a great way to loosen the car up slightly in wet conditions. Hopefully these valves will allow me to do the same with the front. ajbengineering.com/products/a...
The final modification is a pinion correction wedge that fits on the rear axle. The wedge sits on top of the spring, the rubber pad, metal plate and axle sit on top. The idea with this is to bring the nose of the axle down slightly and make a better alignment with the prop shaft. This is only really required on cars that have been lowered at the rear. ajbengineering.com/products/m...
Chapters
0:00 Introduction
02:27 Preparing the front damper
06:00 Refilling the lever arm shock, I used 20wt oil, 10-15wt is recommended by AJ Barnard for road cars
08:00 Fitting the new adjustable valve
13:34 Fitting the damper to the car
26:56 Finishing the front dampers
28:44 The rear axle wedge
33:38 Re-fitting the spring shackles
39:06 Please subscribe!
I should add that I am no way endorsed/sponsored by AJ Barnard; all the parts were bought with my own money.
I'm really trying to push my KZbin channel forward for 2022, if you like the videos it would help me immensely if you would be kind enough to subscribe to my channel
Thanks to Opie Oils for all their support in 2022 www.opieoils.co.uk/

[@mpb7939]

Between you, John Twist and MGEXP all aspects of MGB repair are covered! Excellent video and your car looks great!!!

[@davidrussellwilks]

Thank you so much, I've watched many of John's Videos, I'm sure he has forgotten more about MGB's than I will ever know.

[@rodneystancliff6238]

Thank You for sharing -- As I wrote just a few minutes ago to you -- I now own a '69 MGB-GT. I will be following along watching your videos -- Especially the how - to ones for working on bringing my car back after 27 years of storage. I see the Adjustable Valve will work in the stock front shock absorber so that I will look for. I probably won't get a chance to run her on a track -- but, I like the --- tear down , cleaning , painting , reassembly and finally firing it up ----- Be Proud of what you can do , Thank You -----

[@bshnabel]

Excellent step by step informative video

[@davidrussellwilks]

Many thanks for your kind comments!

[@wallisparnell4464]

Appreciate your info, enjoy learning and know you enjoy making these.

[@davidrussellwilks]

Many thanks Wallis, glad you like them!

[@americanpatriot2422]

Outstanding video and presentation.

[@davidrussellwilks]

Many thanks for your kind message, glad you enjoyed it!

[@MGB-learning]

Another Outstanding video and presentation.

[@davidrussellwilks]

Thanks again!

[@paulbiegun]

Do thoroughly enjoy your videos and look forward to your superb battles on track! Hopefully you will show up at our home track at Road America some day! Cheers, Paul.

[@redbarchetta8782]

Nice. I may have to look into these.

[@davidrussellwilks]

I'm yet to try them out on the track but really looking forward to seeing how they perform

[@windmill1965]

Very useful video. 4:00 You reuse the cork gasket. What if it gets damaged during disassembly? Are these available?

[@davidrussellwilks]

When I looked previously I was unable to find replacement gaskets, so was always careful when I removed them. Looking this morning though it seems as though they are available now mgbhive.co.uk/product/mgb-front-shock-absorber-gasket-set/

[@MorroccoM13]

Hi David, thanks for all of the great videos you make on the MGB. I bought some new front dampers from Moss Motors and also some stiffer valves. Is it OK to just clamp the new damper in a vise and remove the existing valve and swap them or is there a more preferred way?

[@davidrussellwilks]

I think it would be worth having a bit of oil ready just to top up the shocks when you remove the valves. Use some soft jaws in the vise to hold the shocks upside down whilst you swap the valves.

[@jameseastwood4984]

Very interesting, thanks David. I used brand new lever shocks, thicker oil and an updated valve in my MGCC Speed Champ Road Going spec Sprite. To be honest they still weren't that firm, but a huge improvement over worn stock units. Is the purpose of the rear shim to move the pinion to be closer/parallel to the gear box output shaft angle to reduce the uvj error and any vibration ?

[@davidrussellwilks]

The shim at the rear is indeed to lower the nose of the diff and make the prop shaft as level as possible. I'm not quite sure what you mean by uvj error but it does give better drive off the line and stops the springs winding up so much.

[@ianrutherford7060]

Hi David ,excellent video ,could you tell me the reason for angling the differential,what’s the benefit.

[@davidrussellwilks]

Thanks for your message Ian, the idea is to stop the axle winding up on race starts; With the lowered rear springs the nose of the axle can start pointing too far upwards.

[@paulbiegun]

Just wondering if you would do an evaluation on the available caster shim kit (Moss, Costello) to lessen positive caster angle on the street driven MGB with radial tires? Or maybe a prep on alignment for street/race. Regards, Paul

[@davidrussellwilks]

It's an interesting question Paul, the castor kit is not something I have ever considered fitting; the cars races on cross-ply tyres and for me high speed stability is more important than having light steering. The car is fitted with a quick rack and I am generally very happy with how the car handles. That said the shell is a Heritage one and I was told that the rebuilt shells were adjusted to give a castor angle of 3 rather than 7, I don't know if this applied to all the shells though, mine is an early one from the mid 90's. I'd really need to try and get an accurate measurement to make sure. I can certainly make a video on car alignment, I was setting the alignment last night; I go for a slight toe OUT of around 2mm 0.3 degrees. I think a car prep video would be a good one, also covering scrutineering checks for racing. Best regards David

[@davidsmith6212]

Excellent video David. I wondered if you have any comments about pros and cons of these adjustable oil front dampers versus various gas dampers / coil over kits? I guess you are constrained to stick to originals via racing class rules? I would love someone to do the definitive top 10 of handling upgrades on the B as there is a lot of scope to spend a lot of money, but how much of it actually makes a difference….

[@davidrussellwilks]

Many thanks for your kind message David, you are quite correct that class rules dictate the use of lever arm dampers only for our cars. Having previously owned an MGB GT with the Bilstein shock conversion I would have to say that I much prefer the ride with the lever arms. However the tracks I use my car on are usually very smooth so you get get the problem with jounce or harsh handling that you might get with stiffened lever arms on a bumpy road. I think I'd start by finding out what I really want for the car, depending on what you want to achieve and where you are driving the car will influence your choice greatly. Personally, I would always refresh and check the lever arm dampers as a starting point, it's not going to give a true result if you are comparing worn out shocks to brand new ones. You can then make changes one at a time such as the anti-roll bar, shock valves etc to dial in the car the way you want it.

[@michaelmenard8913]

@@davidrussellwilks bit off track, but you mentioned placing an angled shim in the leaf springs? For traction?

[@alexandernicholas244]

Just wondering if you put a link to those adjustable valves for the front lever shocks. I’m in Australia. They look like a good thing. Would be keen to fit a pair to my fronts. I run 600Lbs front springs and 24 mm bar, so would be good to be able to tune damping . Regards. Nicholas

[@davidrussellwilks]

Thanks for your message, the adjustable valves can be found here ajbengineering.com/products/armstrong-lever-arm-adjustable-damper-valves/

[@michaelmenard8913]

So talk to me about your sway bar, I was told to reinforce the mtg area if going 7/8 and above? I came in 3rd in our Houston autocross you comented on. My 1st...

[@davidrussellwilks]

First of all congratulations on the Auto Cross! I use a 7/8 bar with the solid aluminium, mounting blocks. It's well worth reinforcing the chassis leg, mine have torn on both sides in the past. The Auto Cross certainly looks like an interesting discipline, for the track we tend to make our cars as stiff as possible but never need to make as many tight turns in a row as you do. We run with no anti-roll bar or Panhard Rod on the rear (not allowed under class rules).

[@michaelmenard8913]

@@davidrussellwilks is that area braced for your current sway bar? I did not notice in the video

[@davidrussellwilks]

Yes it is, the body shop was able to make a neat repair when the captive nuts tore through the metal. The used a thicker gauge steel, cut the old metal out and welded in the new complete with captive nuts.

[@wallisparnell4464]

Looking to see if you have any system to,prevent spring warp and hopping on acceleration?

[@stevencowan5599]

Hi David, been watching your video on modification shocks and as l live in Sunny Queensland Australia 🇦🇺 l can’t just pop around the corner and pick up a pair of arm’s 😂😂 So are you able to purchase them over the counter or you had them personally done for you. Cheers Steve 🍺🍺🍺

[@davidrussellwilks]

Thanks for your message Steve, I bought the complete damper units from AJ Barnard. ajbengineering.com/products/camber-adjustable-front-damper-unit-for-mgbs/ give them a call and see what they can do. I can probably help with a set of dampers if you need them as an exchange.

[@michaelmenard8913]

How did shimming the pinion angle work out? 3° it looked like? Do stop wheel hop?

[@davidrussellwilks]

Yes, from what I could tell. I seemed to get good drive off the line in the last race; the tyres span up slightly (but I think they are a bit old). The modification did seem worthwhile though, I will know more after more race starts.

[@michaelmenard8913]

@@davidrussellwilks fixin to put a 2.5° on mine. I have more leaves on my springs, but clamped them to almost solid. Left the rears leaves to flex though. It an old drag racing move...