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Autumn Sports Car Classic, Lancaster, NY.
Transmission Related Discussion / install overdrive switch
« Last post by Dkalel on July 02, 2020, 04:06:30 PM »
I am adding an overdrive to my 77 MGB and I was wondering about the gear shifter and how to put the overdrive switch onto the old gear knob. I saw online that they have a cap with the switch you can put on top of the shift knob. Can you switch the old top of the knob with the one with the overdrive switch? I don't have my car at home as it in the shop being worked on or I would be able to figure this out on my own or take a picture to show what kind of knob I have. Has anybody else done this? Any advice will help if you can considering I don't have the knob or pictures. The knob I have has MG on the top and the knob is leather or vinyl and I don't see any way to replace the top from what I can remember what it looks like.  I believe I will have to get a whole new knob for my car or buy an used gear lever with the overdrive switch. Any ideas?
MK II B-GTs ('67 to '75) / Re: '69 B-GT Backfiring and Losing Power
« Last post by Art on June 08, 2020, 12:27:48 PM »
Hi John,

All good advice from Joseph, but from what you're describing, I'd say to take a look at the vacuum and mechanical advance systems on the distributor.  A 69 B would be equipped with a Lucas 25D4 distributor, which is notorious for problems with the vacuum advance disc failing, often with the advance arm separating from the vacuum disk.  This can happen on the later 45D4 type, but less frequently.

The mechanical advance can't handle any hard acceleration on its own and the engines seems to bog and backfire as it tries because the timing is not advancing, just as you are describing.  I'd check the vacuum pot and the mechanical advance system (springs, weights, etc.) for damage, rust or wear

My old adage is 'if it feels like a fuel problem, it's probably an electrical problem' (and vice-versa).

This may not be the culprit, but it very much resembles gas starvation on acceleration. 

Hope that helps you.

Safety Fast!,

B roadsters rubber-bumpered ('75 to '80) / Re: 1977 MGB Bought On eBay
« Last post by Art on June 07, 2020, 09:42:08 AM »
Hi Daryl,

I agree with Phillipe.  I'm not a fan of the Stromberg, but if is in good working order, use it to help figure out what else you might need in rebuilding the car. There may be other areas you'll need to spend money on.

If it is bad and you want to replace it with something else, there are different carburetor set-ups you can install to varying degrees of cost and levels of expertise.  Get the catalogs Phillipe mentioned and you'll see the options, but below is a quick reference:

- New HIF44 - This is a single SU carb that replaces the Stromberg using the same intake and exhaust manifolds.  It's basically a bolt-in replacement that requires the installation of a manual choke kit and some throttle linkage modifications only.  Runs about $600 for the kit.  Good as any SU and minimal work to install, but still a single carb.

- Weber Downdraft - Just as it says.  Similar carb to those used in 70's and 80's European cars from the factory.  Comes as a kit with intake manifold, air cleaner and linkage parts.  Can be ordered as an automatic choke (water or electric heated) or manual choke, which you then will need to install a choke-pull kit to operate.   Also needs an exhaust manifold, as the original intake and exhaust manifolds as a single, inseparable unit.  Note the 77 has a catalytic converter tucked-up under the exhaust manifold, so depending on where you live, you may have to reinstall one or, if like NJ that doesn't require inspections for cars over 25 year old, you can use a header kit or older (pre-1975) exhaust manifold and engine pipe to eliminate.

- New HS6 set - These are new, larger carbs as used on some Triumph TR6 and other makes/models.  Kit comes with a new adapter manifold and linkages for the MGB.  Larger diameter bore and manifold runners gets more air flow into the engine.  Not cheap (about $1900 with heat shield et al), but its not much more than other options when you consider they're new (not needing to be rebuilt) and add performance.  Same deal as the Weber on the exhaust.

- OEM New or Used SU HS4 - These are the older style side-float SU carbs which can still be found both new or used.  A new HS4 kit is much less than the HS6 set-up ($1000 or near half the cost).  In both instances (new and used), the same is needed for the exhaust system as the Weber and the intakes may be equipped with different ports and attachments for old pollution controls (i.e.: PCV valve center of the intake manifold) that you may have to eliminate and plug or figure out how to install.  Also note that the flange thickness of the manifolds varies with later models, so make sure you know the year you are working with the match the exhaust manifold or header to as you find them or order new from a catalog. You also need a heat shield, so if buying used, make sure to get that or buy one from the catalogs.

- Used HIF4 - These are the later internal float SU carburetors used from about 1970-74.  At the moment, these seem to be only available used or rebuilt, though all the rebuild parts are available.* Manifolds are similar but not exactly the same as for the HS4 (see notes on pollution controls and flange thicknesses), but either carb will bolt to either intake manifold and function correctly.  I like the HIF4 because it has an internal thermal adjuster that, when it set properly and works, automatically lowers and then raises the jet to adjust the mixture as it warms.  Same manifold situation as the Weber and HS4 sets.

*On all the dual-carb set-ups, also be aware that clearance for the rear carburetor is restricted by the power brake booster.  You should use a pair of thinner 'pancake' type air cleaners (like the Stelling & Hellings type) because the stock or K&N types will not fit there. With all used carburetors, expect to have to rebuild them, so figure that cost and time into deciding which route to follow.

Hope that helps you.  Good luck with the B and keep us posted.

Safety Fast!

32nd Annual MGs on the Green, Concord, NC. .
Cars for sale / 1976 B Roadster
« Last post by amgba on May 25, 2020, 12:47:59 PM »
1976 B Roadster detailed throughout.  Repaint and interior excellent. Cylinders 135-140. Tires like new. Five chrome wires excellent condition. Front end rebuilt, undercoated and body rust treated, carbs rebuilt. Like new top, small tonneau and full tonneau. Recent service and tune up. Everything works as designed. OVERDRIVE! Needs nothing. Alexandria VA. Ed for more pics at or 703-310-4097.
Engine Related Items / Re: Block for V8 conversion
« Last post by Art on May 22, 2020, 12:52:27 PM »
I agree with Scott.  Forget about the horsepower, the 350 Chevy or 351 Ford are all iron and way too heavy for the suspension or any kind of decent handling. 

The real beauty of the original Costello/Factory MGB V8 swap was that the GM 215 CID or the Rover 3.5L (essentially the same engine) were aluminium blocks and heads, so were about the same weight as the cast iron 1.8L I-4 they replaced.  Only suspension change was to use steel-sleeved bushings on the inner control arms of the front end (still available from Moss or Victoria British catalogs).  They also tended to run cooler for the same reason.  Note that the Rover 3.5 is 'based' on the original GM engine that was used in the Buick Skylark, Oldsmobile F-85 and even the Pontiac Tempest for their first few years of production.  As a unit the GM and Rover engines are interchangeable.  They are also plentiful.  GM built nearly 3 million of them over 3 years in the early 60's and BMC used the 3.5L and a later 4.0L variant up through about 1990 in various models, including the MGR V8.

I helped a friend in Costa Rica with older Range Rovers equipped with the 3.5L V8 back in the mid 80's that were having both reliability and altitude problems.  We ditched the SU carbs, Lucas ignition, distributors and alternators for Holley or Carter 4bbls on Edelbrock or Weiand manifolds and either Crane aftermarket or stock GM HEI distributors along with Delco alternators. All bolted right in and performed really well and reliably.

Finding a Rover (or GM) and equipping it with aftermarket performance gear (all still available from performance catalogs like JEGS) can make a pretty formidable performer in an MGB.  And you lose nothing on handling due to excessive weight, like the CI V8s you're considering.  Conversion kits are available from Andy's Motorsports ( and others.  Consider using the Mustang 5 speed box conversion as well.

Safety Fast!

Use a good spray adhesive, like 3M, and insure you don't get it anywhere you don't want it. When fitting your pad, get help to maneuver it into position where you want it before pressing the pad down into the adhesive. Once down, it's not going to move. Use a plastic or wooden tool to work the edges of the material under the reinforcement under the bonnet/hood. It looks really nice and neat if you can get the pad centered between the reinforcements and then tucked neatly under them.

Scott Stuchell
Moss Part #409-008.

Ralph Littlefield
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