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Thread: MGB smog control ????

  1. #1
    Jedi Warrior Bob Claffie's Avatar
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    MGB smog control ????

    As the 2 TR8's I had a opportunities on fell through I have started casting my line in the MGB waters. Last night while searching ebay I found several "inexpensive" MGB's any one of which would do as a project.

    My observation of these cars brings me to todays' question. Invariably this group of six or eight B's , from 1968 thru 1979, were stripped of all the smog control. No air pumps, no air rails. Why is this ? I understand that it "neatens up" the engine compartment somewhat but also makes the car nominally illegal.

    From the engineers and engine builders here, what is the rational ? Is there any substantial performance benefit ? I can't believe it takes more that 1 or 2 horsepower to run the air pump. What is the fact or fallacy behind this indiscriminate removal of equipment ?

    We have had three MGB's in the family, one with and two without and remember no significant difference in performance or reliability. Potential owner wants to know. Thanks, Bob
    Sunbeam Tiger mistake is GONE, bring on the next project !

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    Yoda TOC's Avatar
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    Re: MGB smog control ????

    Personal experience, any car with emissions in that time frame suffered from loss of power and mileage with the emissions controls of the day.
    I can tell you, but not tell you how I know, that removing cat, egr, distributor vacuum controls, air pump and injectors, made them run like the ones the year before the garbage was installed.
    I have seen (same disclaimer) air pumps taken apart, gutted, and only a shaft and bearings spinning.....cats pulled and gutted, BB's in hoses, and under air injector lines.
    How far back does Mass go on emissions testing? Up here, it's a 20-year sliding scale.

    Usually, manufacturers added stuff to existing engines, so internals were pretty much the same.
    Then they started in with swirl, combustion chambers, cams and all that rot.
    They didn't get close to making them functional until computers and fuel injection.

    We have tested internally stripped cars, and they are either the same or better on emissions in that era.

    In mid 70's, big Lincolns with 460's suddenly wouldn't get out of their own way. Seriously.
    Took one apart in the dealership once, found they had changed the timing gears, keys in different positions, marks to match.
    Ordered out 460 Police Interceptor timing set, the car would light up the wheels for half a block.

    When I was an emissions specialist, we had the papers handed to us in classes we had to attend, that California, which had stricter emissions controls than anybody else, used 10% MORE fuel for the amount of licensed vehicles than any other state in the union.

    We pulled the garbage off, fuel economy increased by about....10%.
    Go figure.

    MG's should not have had emissions devices until later than what, 70? I can't remember anymore.

    And early emissions (up through about 1970, 49-state) consisted of a PCV valve and thermactor air cleaner.
    No cats, no egr's, no air pump.

    Dave

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    Yoda TOC's Avatar
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    Re: MGB smog control ????

    I thought I still had my "bible" on emissions controls. Listed by year and make what was required. We needed it from back when we had to do "visual" inspections, before our folks listened and realized visual made no difference...it was the tailpipe.
    I do remember one other thing from those days...

    Limits were hard....you failed by .0000001%, you failed.
    Except for British cars.
    No kidding.

    British cars were exempt from the strict requirements....IF the owner had the original paperwork from importation (new or used) that stated specifically what the levels were upon acceptance for importation.

    So, of you were allowed 3% of whatever, and your car was accepted with 3.75%, that was the number they had to use for go-no go.

    Dave

  4. #4

    Re: MGB smog control ????

    Bob, I can't speak for MGB emissions devices from that era (my MGB is a UK car that never had any of them) but I've had 2 different '76 Toyota Land Cruisers -- one with all emissions stuff removed, one with all factory emissions stuff present. Don't know if it made a lot of power difference, but boy the mess of vacuum hoses and vacuum switches and 1970's computers and... had I kept the second one (with all the factory stuff) I'd have put all that stuff on a shelf.

    Utah does emissions tests by county -- and my county doesn't test. If I lived down in Salt Lake City still, I'd have gone with a car '67 or older as that's the cutoff here; no rolling cutoff, goes all the way back. May still eventually wind up with an older car so as not to worry.

    Part of me would be interested to see if my car without any emissions pieces as from the factory would pass the 1970 emissions levels. Curious, but not enough to do anything about it.
    Drew Frink -- http://www.drooartz.com
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    Yoda TOC's Avatar
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    Re: MGB smog control ????

    My 1950 Ford, flathead V-8, did just that. I still have the printout in the glovebox, 25 years later or so.

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    Great Pumpkin JPSmit's Avatar
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    Re: MGB smog control ????

    In terms of the B specifically, If my Midget is anything to go on, the emission stuff failed and/or needed to be replaced and the stuff wasn't there to replace it. I have seen a few cars with working smog kit and I understand that there are California clubs that keep engines to be swapped in for testing, but, it seems like many air pumps broke and were removed long before anyone thought about tearing out the smog stuff. Likewise, i know mine had gulp valves and charcoal canisters and ERG valves that needed replacing and/or re-setting at certain intervals - I have no idea where you could even get such things now.
    John-Peter Smit
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    Jedi Warrior Bob Claffie's Avatar
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    Re: MGB smog control ????

    I mostly agree with JP. As I reflect on our personal experience, I recall my son's MGB was "desmogged" due to necessity, his "gulp" valve failed and the air pump seized up. This may be what happened to the six MG's I chose to follow on ebay not a search for more performance or some other obscure reasoning.

    I also agree with TOC, I have no love lost with Cat converters or vacuum retarding distributors, likewise lowered compression pistons. Actually most of our LBC's are driven so little (a few thousand miles a year) that the pollution we should be saving doesn't amount to a nit in the real world..

    What triggered this thread was the across the board elimination of air pumps which ultimately may have been caused by the lack of replacement parts or their costs

    Smog testing here in Ma is only performed on cars new enough to have an OBD2 computer testing plug. I "think" there is something on the books about a visual inspection of smog equipment on older cars but I have never seen it applied. As an aside, I DO have cat converters, air pump and carbon canister on my replica cobra, as I built it before replicas were made exempt from smog testing (it actually passed a couple times) but mostly to cut down on the sound of the exhaust. Bob
    Sunbeam Tiger mistake is GONE, bring on the next project !

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    Yoda TOC's Avatar
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    Re: MGB smog control ????

    It wasn't just British cars of the era that seized up smog pumps.
    Geez, we used to change a lot of them..and the little narrow belts that drove them (specifically designed to snap when they locked).
    Taking them apart wasn't all that hard, and the innards came right out. I knew guys who cut a new shaft, put new bearings in, and re-mounted....spun just like it was supposed to.....gutted the cat....looked like it was supposed to.....plugged the retard advance.....looked like it was supposed to....jammed the Thermactor valve on the air cleaner open from the inside...no more erroneous hot-air incursions heading through Beale's Cut or climbing the Ridge Route.
    Look at the figures published for horsepower for 1967, then look at the same engine series as the years progressed.
    I did that for a guy once...he was amazed.

    Never did hear...does Mass have a fixed year or sliding scale for emissions?
    Dave

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    Yoda PAUL161's Avatar
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    Re: MGB smog control ????

    Quote Originally Posted by Bob Claffie View Post
    As the 2 TR8's I had a opportunities on fell through I have started casting my line in the MGB waters. Last night while searching ebay I found several "inexpensive" MGB's any one of which would do as a project.

    My observation of these cars brings me to todays' question. Invariably this group of six or eight B's , from 1968 thru 1979, were stripped of all the smog control. No air pumps, no air rails. Why is this ? I understand that it "neatens up" the engine compartment somewhat but also makes the car nominally illegal.

    From the engineers and engine builders here, what is the rational ? Is there any substantial performance benefit ? I can't believe it takes more that 1 or 2 horsepower to run the air pump. What is the fact or fallacy behind this indiscriminate removal of equipment ?

    We have had three MGB's in the family, one with and two without and remember no significant difference in performance or reliability. Potential owner wants to know. Thanks, Bob


    Bob, The wifes 72 MGB has all the smog equipment in place and is in perfect working order. When I restored the car back in 05, I wanted it as it came from the factory. I have driven the same year with and without the air system and can tell you, there is no difference in performance of a factory stock engine! I'm talking street engines here, without any outside high performance equipment installed. Different year engines will have a different performance scale, but for the same year, there's no change. Here's a shot of the wifes factory original 72 engine bay. Only coil is later model. PJ

    Oh, For the critics, I've known this car since new and it DID come originally with that fan on it!




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    BECAUSE OF THE BRAVE!

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    Great Pumpkin DrEntropy's Avatar
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    Re: MGB smog control ????

    Is it on backwards, Paul?!?
    '64 MGB, '67 Lotus Elan S-3 DHC,'69 Lotus Elan +2
    '78 Alfa Romeo Spider-current Daily: O=\*/=O
    '84 300D Turbo-"Diesela"-SWMBO's Daily: OO|≣|OO
    '66 Alfa Romeo GT - Upscale Yard Art: Oo=\*/=oO
    Chaos & Mayhem PTY, LTD..C.I.O. & Floor Sweepervisor

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