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Removing all smog equipment and my heater

RobSelina

Jedi Warrior
Offline
Well, I started removing the heater and the smog system today. I want to clean up the engine bay a little, simplify it to the point that I understand it /ubbthreads/images/graemlins/hammer.gif and hopefully free up some parasitic HP and maybe a little gas mileage.

Anyway, the factory shop manual has helped me figure it out for the most part, but if anyone has any advice after doing it themselves I'd like to hear it.

A few specific questions so far:
1 - should I bother having a distributor vac advance?
2 - do I re-route the two lines that go into the heater so they're connected to each other? I believe that's the procedure if I'm reading things right....


BTW, it's a 75 MG 1500.

Thanks,
Rob /ubbthreads/images/graemlins/thumbsup.gif
 
don't know #1, but for #2 i think yo ucan just plug the outlet (outlet) portion from the heater and stop it with the valve - or plug it there. connecting the two hoses would kind of negate the whole minimalistic approach you've got going. i say plug them where they start (just a capped piece of pipe hose-clamped inside a short hose would do fine.

possible drawbacks though - you will lose the last ditch effort to cool your engine if the radiator fails to do the job. you could always remotely mount your heater core /ubbthreads/images/graemlins/smile.gif lol
 
I didn't notice that the connection is already made D-OH! That takes care of that.....

New question - what on earth is the size and thread pitch for the plugs that need to replace the Air Manifold? They seem to be fine thread 11mm which I thought was odd.....
 
Rob, the threads are 7/16"x 20. SAE #4 plugs work wonderfully, as the cone on the end matches the flare on the internal tube, and no washer is required. #4 AN plugs will work, too, just make sure to use the steel plugs, and not aluminum.
Jeff
 
Rob:

You can also remove the heater feed pipe from the water pump on a 1500. It's about 2 feet long and runs along the right side of the engine about half way down, under the manifolds....screws into the back of the water pump. If you remove it, a standard plumbing pipe plug will fit it (I forget what size).
If you are not driving in bumper to bumper trafffic or chugging around at 1500 RPM in third gear, you can delete the vacuum advance with no change in performance.
 
cool 7/16" x 20 did the trick on the air manifold. I'll get some plugs next time I'm in town. Now to find bolts that fit in the EGR line on the exhaust manifold and the intake....
 
Rob - A smart guy (also from New Mexico) once said "The first rule of tinkering is 'save all the parts'".

Okay, Aldo Leopold was talking about the environment but the message is the same here -- many states (including next door in Arizona) still smog test all post-1966 cars. You should probably save everything you take off against the day when you or someone else might have to restore the emissions equipment.

BTW, my TR4 never had a heater, on those the factory just used the plumbing plugs Nial mentioned to plug the water pump outlet and head inlet.
 
yea, i'm saving all the smog equipment, bumpers, etc. If I ever have an issue, we move, I sell it, etc I think having those parts will make matters a lot easier....
 
This upgrade was very worthwile! The increase in power is substantial, and the run on problems and backfiring issues I had are gone. It's like a new car, it has so much more 'go' and the engine just feels smoother and happier.

I think the new found breathing ability has put a strain on the fuel pump though...it died on me today. I'm starting a enw thread about that one though /ubbthreads/images/graemlins/smile.gif
 
Just thought I'd post a couple of pics of the engine bay...it seems so empty now! I still need to do quite a bit of finish work, but it's comming along...

mg11.JPG


mg12.JPG
 
i have my equipment out to paint the engine bay - now because of you i'm not putting it back in. . . instead of the carbon can i'm thinking of making a little toolbox from extra sheet metal laying around. i figure good for 'on the fly' fixes and good duct tape storage bin, lol.

good job rob
mike
 
Hey Mike - I like the little underhood tool kit idea! trunk space is at such a premium in these cars...
 
i think i'm doing my floorpans with black diamond plate, the scraps would do nicely - i bet i could sell them on ebay if come up with a good design, but would end up in jail for requiring the deletion of emmissions equipment, lol. keep an eye on my 'progress' forum about the switch from the 1500 to 1275 and i'm sure you'll see future discussion about it.
 
keeping my eye on it /ubbthreads/images/graemlins/smile.gif

I'm probably going to do a rotary conversion at some point, but not for a while. I want to see what I can do with the 1500 first /ubbthreads/images/graemlins/smile.gif
 
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