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MG MGB GT V8 Factory Originals Technical - California Convertors?

I'm in the early stages of planning out a conversion. I was curious if anyone out there has gone through the whole California referee ordeal to make their car legit in California. I'm curious as to what emissions componants are being used to pass inspection. I would like to figure out what headers, catalytic convertors, exhaust system I should be looking into.

1978 MGB (3 working cylinders:)


1978 MGB for convertion in Ca. Forget it, buy a mustang
...a brand new It'll be cheaper.

Not really a money issue, plus I love my MGB. The only part I hated about it was almost getting killed getting onto the highways out here due to short ramps and the whimpy 4 banger engine. Plus having to drive in the slow lane at 3500 rpm on the highway is not really fun highway driving. That combined with the fact that I don't like mustangs or just about any other American car.

I own just about 2 SD1's worth of parts, one of which is completely functional and I believe I'm short one bell housing if I want to keep from scavenging the working vehicle. The MGB is a nice California rust free vehicle in need of only minor dent work and better suspenion to be a beautiful vehicle.

Anyone got anything positive to share?

1 1978 MGB
1.7 1980 SD1's

You may wish to consider efi. The N/A spec hot wire type was designed to run cats after about '90. Must you pass emissions for a contemporary car, or for the year of your B?

Goto and search the mailing archives. I seem to remember there being a long thread about this on the V8 mailing list. A quick search for California turned up quite a few messages.

Michael Hartwig

Thanks for the info. I found the thread from Scott Pontius, whom I have been in contact with. He has a similar 78 Fed EFI conversion and is dealing with many of the issues I am sure to face. The biggest problem seems to be the use of manifolds, since the refs want you to keep the original stock SD1 manifolds with EGR valve, O2 sensors and catalytic convertors. He mentioned you may be able to get a waiver for the manifolds if they deem them unavailable in a parts check. Considering how few SD1s that were CA legal made it here, they may be hard pressed to find these with the proper emissions fittings. I plan on contacting the CA refs and trying to get an unavailable waiver for these parts if at all possible before trying to fits new tubes with the fed emissions equipment.


Hi Chris.
I'm back from vacations guess where? California
sorry i was so negative about your project but dealing with Ca emissions will do that to you.
The good news is with enough time and money anithing can be done, well having 2 SD-1s helps a lot because that is the way you want to go. The referee will check standarts for the donor car in your case 1980 SD1, it has to be fuel injected (CA cars were all fuel injected as were TR8s) The main problem is going to be the exhaust manifolds if you have them you could fit them with major surgery to the frame rails,Maybe even fabricate a tube frame rail around the exahust the main porpuse is get them in once you get them in the EGR comes out from the drivers side manifold, the oxigen sensors and catalitic converters bolt rigth to the manifolds. Dont forget that they will also check for the apropiate trans that came with the car (SD1 5 speed or TR7/8 5 speed). Keep all emissions original to the car (abdsortion cannisters etc.) and all engine emissions of donor car. well good luck let us know of your progress (i have some SD1 parts in my colection just in case)

I have had several people recommend trying to use the original SD1 cast iron manifolds, but using 2 of the left hand manifolds since they angle inwards at about 45 degrees. I've also had several people tell me that they will still hit the rails. I guess I'll have to wait for my engine to come back from the rebuild shop and do some fitting tests to see exactly what I'm up against. I sent for the Heritage build info on the SD1 so that I can prove the engine number matches my vehicles VIN and that the donor vehicle states CA emissions, thus it should be an exceptable CA engine to CA car engine swap as long as I can get around the manifold issue. I also had someone suggest using block huggers drilled to accept the EGR valve, and O2 sensors and then submitting for a CARB aftermarket approval since they are just headers. I'll have to due some serious research into what that would entail though. Probably if its like most CA bs it is unfeasible. But it would make future conversions much easier for others in this state.

Chris Schwerzler

This thread was discussed between 05/08/2000 and 20/08/2000

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