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MG Midget and Sprite Technical - Exhaust question

I have a 79 midget with a catalytic converter.

Since I have to replace a cracked exhaust manifold, I would prefer to go with the non catalytic pipe/manifold solution. It would appear that I can obtain a new manifold and new forepipe and eliminate the catalytic converter entirely. Does any memember have any experiences they can share? thank you.
GB Greg

Is it legal in the States to do that? I believe that in the UK if a converter was fitted as standard equipment it had to be retained. Sure someone will correct me on that if I'm wrong.
G Williams (Graeme)

In the US, each state has a different rule, some are more lax than others. In some cases, it is county by county. One of the benefits of living in a Federation: the laws/rules can vary depending on where you are in the country (you should see what the liquor laws are like!). For an OEM the rules are national, but for an owner, the rules applied are local.

Most states only require of the owner (if they require anything at all, after a certain number of years) that the performance be met (with the performance requirement usually set by the year of manufacture), not how it is met. If you live in an area where that is the rule, you can take advantage of the fact that most cars can be tuned to pass, even if only for the day of the test. The ideal way to do it is to use an O2 sensor to adjust the engine to pass, and then, if that is too lean for comfortable, long term use, to adjust it back, when you get home after the test is completed.

In general, a well tuned, well run engine will do pretty well at meeting the regs from the '70s, with only a bit of adjustment required (usually, leaning of the mixture). Things get more complicated if trying to balance NOx against CO or HC (improving one makes another worse), but the '70s regs usually have plenty of margin to find a sweet spot, even without the cat.

The key thing is that a lot of the emissions equipment is added to make sure that all engines, regardless of build variation and of customer care (or lack of) will still meet the reg. after 10 years of (hard) use. This leaves a fair bit of wiggle room for one person with a well set up engine to get a lot of their performance back, and still meet their state's rules.

Norm
Norm Kerr

Norm is essentially correct.
I live in a very rual state, less than 500,000 people. For such an old car as this.... driven so little. Manufactured during a time when change overs were common.. Its more of a ease of maintainace, cost, and simplicity. The cat is an unecessary complexity in what is considered today as an antique car. the quesiton remains... I think there were two manifolds for this year and two short pipes... I think I can swap out for the simplier manifold and simplier fore pipe...I am still unsure if that will work.. So my question is... does anyon know.
GB Greg

Go for a tubular manifold and get and exhaust to match.
when something breaks it is always the best time to upgrade!
Onno K

gee greg thanks for doing your part to kill the planet

the next time my son little timmy ask why he has to die from emphazyma and clogged longs... ill let him know there are people like you greg that dont care about sick little boys and only think of them selfs

jesus... please keep my little boy timmy safe in heaven

oh wait.... yeah, I almost forgot, I dont have a son... MY bad...your cool, polute away...hahaha

prop
Prop and the Blackhole Midget

GB GREG,
Ive never seen anyone do anything but dump the stock set up on that model.

At a minimum we used to take a crow bar and smash the ceramic honey comb out of the cc. It would just leave it a hollow tube and then just reassemble. Everyone I knew put a side or down draft weber on them with a tubular header. I may still have a header but I think its for a spitfire. Where are you in NH? The big problem with those engines as I remember was the crankshaft thrust bearings... They used to fall out and cause all sorts of havoc in the bottom end.

Anyway, Im sure you can change the exhaust header out no problems. Do you still have the smog pump on it? I think the stock carb needed the needle on the piston to be converted to an earlier model so that it could be adjusted to run richer. I cant recall.

http://www.teglerizer.com/triumphstuff/75w_carbswap.htm

This was for a triumph but is good for a read if you havent seen it. hope this helps.
Steven Devine

Steve,

Turns out, for that year, depending on which state the car was sold in... It either had or did not have a pump.. (I believe California had the pump, but no cat, for some reason).. Anyway is no pump.

Yes, I could smash the Cat out. But the cat is not the problem. A cracked manifold is,... and apparently, the interface to the forepipe between a 'standard' and 'cat' manifolds looks difference, (two bolt and donut vs. three bolt and gasket) (again at least the way it appears in the British Vic catalog) British Vic depicts two manifold options. Cat and non cat, and the bolt ups to the fore pipe appear different. I am guessing and hoping the interface to the block are the same.

I have had not bottom end problems... but then again. The beast is only a summer toy, and not driven hard.
It really was never designed for American highways (prolonged high speeds)... but is loads of fun on those winding VT and NH dirt roads. (30-50 mph.) There are never any cops, but you do have worry about the damn moose.

My wife and I have decided that MG stands for Moose Gooser.... and the Midget could easily pass under a full grown adult. Knock out the legs and you would have 1500 lbs of moose burger in you lap.
GB Greg

I don't think Norm is correct, at least not in a technical sense. He may be correct in a practical sense.

I don't think the regulations regarding emission control systems are allowed to be more lax than the federal standard in any U.S. jurisdiction, though they can be more stringent.

So, while you may be less likely to get caught removing a cat in New Hampshire than in California, I'm pretty sure it is illegal either way.

Below is a quote and link from the EPA regarding tampering and defeat devices. In this quote, CAA = Clean Air Act. This looks like a summary/intro and not the actual regulation. It is possible that a study of the regulation in detail would lead to a different conclusion, but I doubt it.

Charley

http://www.epa.gov/enforcement/air/index.html

Tampering. The CAA prohibits anyone from tampering with an emission control device on a motor vehicle by removing it or making it inoperable prior to or after the sale or delivery to the buyer. A vehicle's emission control system is designed to limit emissions of harmful pollutants from vehicles or engines. EPA works with manufacturers to ensure that they design their components with tamper-proofing, addresses trade groups to educate mechanics about the importance of maintaining the emission control systems, and prosecutes cases where significant or imminent harm is occurring.

Defeat devices. It is a violation of the CAA to manufacture, sell, or install a part for a motor vehicle that bypasses, defeats, or renders inoperative any emission control device. For example, computer software that alters diesel fuel injection timing is a defeat device. Defeat devices, which are often sold to enhance engine performance, work by disabling a vehicle's emission controls, causing air pollution. As a result of EPA enforcement, some of the largest manufacturers of defeat devices have agreed to pay penalties and stop the sale of defeat devices.

C R Huff

and yet eatting refried beans at lunch, is perfectly legal...proof that obama hates an oder free ohmerika

prop
Prop and the Blackhole Midget

GB GREG
Well, Are you just over the border or in the white mountians! I do know where the oldest junkyard in America is! Lexington Mass... Wow its almost time to throw the Brits outta here again... Every year the same thing. Yould think theyd let them win one just to be fair! Anyway theres a late model Midget in there...If you think its worth your time let me know.
Im not sure what the asking for a price is but I could find out if your looking to go that route.

CR Huff
Why does the same conversation always appear, should my car be equiped with smog junk... California Bla bla bla...Look this is the east coast not cali..
I dont care what the other states are doin.. Last time I went to get my inspecton sticker the kid said something about my turn signals were out! I told him great they didnt become an option until 2 production models later. He said fine and I was good to go.
He put the newsticker on and vrooom I was outta there I of coarse I fixed them right away. I have a 1958 MGA,the kid doing the inspection was 18. My car was 37 years older then he was. He had no Idea. If you cant get people to check the lights, what makes you think there going to climb under your car to get dirty just to see if inside your catalytic converter the honey comb is still there. Never gonna happen out here....Most dont even know they were supposed to havem. Sorry to rant,
Im just saying my piece out loud and dont mean to offend.
I just get a little worried the EPA will vote my hobby in to illegality!
Steven Devine

Steven,

I don't know why the same conversation always appears. I'm not the one who brought it up. You can take that up with Graeme and Norm.

What does a 58 MGA have to do with a conversation about the legality of removing a cat? It didn't come with one in the first place, so it would be a pretty good trick to remove it.

I didn't say that you on the east coast would get caught without a cat. I just said that my interpretation is that the east coast can't make it legal to remove it.

Charley
C R Huff

Hey Charley,
Didnt mean to get you riled, In Massachusetts if the vehicle is over 15 years old, It doesnt get smogged tested. They do safety checks only.
Lights,wipers,horn,mirrors,tires,handbrake.

They do not look for output ratios of exhaust gases. Hence no reason to look at the catalytic converters.

All I meant was a car out here that old may as well be a spaceship because most inspection station usually are unfamiliar
with older vehicles.

I have several times been told my car needs new ball joints in the front end....I always say they certainly would be new... as the car has king pins...they are always baffled.

Anyway, thats my story and Im stickin to it.

Have a good one....whatever it may be!
Steven Devine

guys,

While I appreciate the CAT comments.... In New Hampshire, with an antique vehicle, now not driven much more than 1000 miles a year, if that... registered as an antique... the cat question is rather moot. If I install tubular headers the cat is goes.... So forget the cat.

Back to the exhaust header. Ok I got the old cracked one off. The engineer (dare I call him/her that) who placed those bolts underneath the exhaust manifold should be taken out and shot. Back to my origional question, according to Brit Vic, there appears to be two different manifolds for the 1500 engine...Can anyone answer 75-76 and 77-79 WHY and HOW they are different?

It would also appear that my EGR valve may be unsalvagleable.. I hear removing it and plugging the manifold may result in pinging... Any feed back on that?
GB Greg

This thread was discussed between 12/03/2013 and 18/03/2013

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