MGB & GT Forum

Just purchased a '77 MGB in fairly good condition. Needs a lot of work and maintenance but hey it's gonna be fun!

This MGB has been setting up for a couple years only driven occasionally and needs a lot of regular maintenance. The air filter is one of the regular maintenance items!

So I have a question. Are there any air cleaner (regulator) mods for these MGBs? The air cleaner is not attractive at all and I was wondering if there's any good modifications that can be done not only to improve it's appearance, but it's performance as well.



Edited 1 time(s). Last edit at 2015-07-29 02:51 PM by jportermm.

Personally I like these:
http://www.moss-europe.co.uk/shop-by-model/mg/mgb-c-v8/fuel-system-induction-controls/air-filtration-induction/k-n-performance-air-filtration.html

Bit pricey new IMO so I got a pair with filters on flea bay for about £50

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Bernie

"discere mutari est"

Wiring Diagrams: http://www.advanceautowire.com/mgb.pdf
Paul Hunts very useful site: http://www.mgb-stuff.org.uk
Manual for download: http://www.geomatique-liege.be/MGJP/DocumentsPDF/MGB_Workshop_Manual.pdf
UK MoT guide: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/518634/mot-inspection-manual-for-class-3-4-5-and-7-vehicles.pdf
Some basic guides: http://www.howacarworks.com/

1970 Roadster (First Reg July 10 1970). Std exhaust (Bell SS) AFAIK rest is bog standard

There is even a set on Flea bay (UK) now:

http://www.ebay.co.uk/sch/i.html?_from=R40&_sacat=0&_nkw=mgb%20air%20filters%20k%26n&rt=nc&LH_Auction=1&_trksid=p2045573.m1684

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Bernie

"discere mutari est"

Wiring Diagrams: http://www.advanceautowire.com/mgb.pdf
Paul Hunts very useful site: http://www.mgb-stuff.org.uk
Manual for download: http://www.geomatique-liege.be/MGJP/DocumentsPDF/MGB_Workshop_Manual.pdf
UK MoT guide: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/518634/mot-inspection-manual-for-class-3-4-5-and-7-vehicles.pdf
Some basic guides: http://www.howacarworks.com/

1970 Roadster (First Reg July 10 1970). Std exhaust (Bell SS) AFAIK rest is bog standard

http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=29000

Part #103 in this pic

I don't see how the ones you suggested would fit? Can the Zenith-S air filter/manifold housing be removed and fitted with something else?

The great divide strikes again

The short answer is no.

The housing is designed to control the amount of air flow and is balanced to the piston movement and the taper of the needle. There are a few people, emphasis on few, who have reground the taper of the needle to work with a different air cleaner mechanism. This process is not very well documented at this time and requires a very high degree of accuracy as the changes to the taper of the needle can be measured in thousands of an inch.

That's what I figured. I was more concerned with the regulator part in whether or not I can change that out with a nicer looking/better performing regulator.

Whoops sorry forgot you don't have proper carbs

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Bernie

"discere mutari est"

Wiring Diagrams: http://www.advanceautowire.com/mgb.pdf
Paul Hunts very useful site: http://www.mgb-stuff.org.uk
Manual for download: http://www.geomatique-liege.be/MGJP/DocumentsPDF/MGB_Workshop_Manual.pdf
UK MoT guide: https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/518634/mot-inspection-manual-for-class-3-4-5-and-7-vehicles.pdf
Some basic guides: http://www.howacarworks.com/

1970 Roadster (First Reg July 10 1970). Std exhaust (Bell SS) AFAIK rest is bog standard

As more or less stated above the single carb on your car and the air filter housing is part of a desperate attempt by MG to meet US smog requirements. The system is a bit of a sore spot for MG folk because quite frankly it's not very good. Some would say terrible. If you mess with the air filter and make it breath better then you will get more air and the car will run lean. This will only hurt performance, contribute to over heating ect. Ect. Why not tune the carb to run a little richer? Because it's a pain and the real solution assuming that you don't have to pass a smog test is to get a good set of S.U. carbs and an earlier intake and exhaust. Or if your not very bright then you could get a weber.

The Weber is not THAT bad, and the supply of SU manifolds and carbs is pretty thin. It is a big step up from the single ZS. Add an appropriately curved dizzy and you are in pretty good shape.

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Cogito ergo sum periculoso

thin? They made 13 years of them and hundreds of thousands upon thousands.
You can pick up a set of Hs4's or Hif4's any day of the week.
If he OP wants to improve performance,looks,engine breathing,throttle responce a weber is not the path.

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So where do I find these S.U. Carbs and earlier intake and exhaust (Mossmotors?) and what am I looking for? I like the idea of better performance AND better looks.

Found none at the last big swap meet. Even worse trying to get the linkages. You can buy a brand new Weber.

I agree, SU's are better than the Weber, which is far better than the late ZS. Well prepped, not leaking, jets, needles, springs, oil all just right, they are great.

Now, the Weber is a good carb. The problem in the B is the low hood does not allow a tall enough air cleaner. As supplied, I am surprised it runs over idle. Something I have made much better. Just like people who don't like SUs because they don't know how to tune them, people trash the Weber because they miss-use it. It has very good response and flows twice what the engine can handle. You can bolt it on and it works. Given a dyno and enough parts, you could tune it just as well as SUs. Or, just go EFI and get even better performance.

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Cogito ergo sum periculoso

Welcome aboard Jason P...

I had this exact same thread 8 or 9 weeks ago when I joined.

These options being thrown at you cost big freakin' bucks. The ZS gets a bad rap. I have no issue with it.

I see just as many "how do I make my weber run" and how do I make my SUs runb" threads as "how do I make my ZS run.

Someone will be along in 5 minutes to post a picture of an MG that caught fire and burned the hood.

One thing true - You can't make the ZS run right with a low flow filter element. You can take off all the smog, EGR, PCV and the hot air box. I got a chrome snorkel - looks a bit goofy till I find something better but you can also paint the air box and it won't look that bad.

However, if you have deep pockets and are so inclined the dual SU mod is actually not bad. It's just not the first thing you need to do to the car.

the next thing you will be told is you have to get rid of 100 lbs of useless weight inside the rubber bumpers and convert teh car to chrome or you will probably DIE!

Us late model folks get no respect and we gotta stick together...

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The goal - Reliable summer driver interspersed with mechanical tinkering...
Motto - "Driving fifty in the twisties..."
On Mods - It's your damn car - Do what you want. Haters gonna hate...
On SUVs - Drive your B like a soccer mom is texting her friends about how she wants to kill you...
Red Betty - http://www.mgexp.com/registry/GHN5UH418165
Bart - http://www.mgexp.com/registry/GHD4U146898G

I have a weber 32/36/dgev it works fine for me. Stable on idle, start well, ride well, no problem of performance and I'm doing about 30-33 mp/g (imp. gallon) around 25-26 mp/g (US gallon).I like the inexpensive air filter, the electric choke and it is possible to replace with a manual choke, I already have the kit.
The throttle cable is easy to setup as well. A single carb is better than 2 carbs for me; no matter how great the SU carbs could be it is one too many. This is 1.8L engine and one carb should be enough.

When I bought the car I have the choice (from the PO) to remove a weber or re-install a fresh rebuilt ZS; I chose to retain a weber over the rebuilt ZS.

Based on my previous experience with my first MGB, I put a clone of weber (motorcraft maybe from a smashed pinto, comet or vega I don't remember) which works forever.
Another alternative exists from MossMotor but it is expensive I believe:

http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=37330

Before changing the carb make sure the rest of the engine is okay (valve, head, ignition, timing chain, camshaft, compression). No matter what kind of carb you have, if the engine is tired there is nothing to do except a rebuild of engine.

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1977 MGB Red 'Victoria' and 2018 Jaguar XE 'Meghan'
All Classics:
Married, 2 children, MG MGB May to December, Jaguar the rest of the year.