Spitfire '80 Spit Emissions Removal Info

[kritter]

Hello, all. A noob here for sure. I've read where all the emissions stuff put on later model Spits significantly effected performance. Assuming I don't need to meet state emissions standards given it's age, can all this stuff be removed? Does anyone have (or know of) DIY info for this? Thanks for reading.

 

[Mark Jones]

Removing the air pump and rail does improve performance since you are no longer wasting hp to turn the pump. There's no reason to remove the charcoal canisters or the catalytic converter.

I can't remember if I followed a set-by-set proceedure when I removed the emission equipment from my 80. I think I just went ahead and removed it and plugged the holes in the head where the air rail had been.

 

[TR3driver]

It's true that removing the air pump improves things a bit, but don't expect it to magically turn it into a non-smog motor. There are a lot of other, deeper changes involved, including compression ratio, camshaft, carburetion, manifolds, etc.

Also don't forget that smog laws sometimes change; you could have to pass a smog check in the future. So save anything you take off, and try not to do anything that can't be easily reversed.

 

[tosoutherncars]

Removing the air pump and rail does improve performance since you are no longer wasting hp to turn the pump. There's no reason to remove the charcoal canisters or the catalytic converter.

I agree about the charcoal canister... but did the Spits of this era come with the Zenith CD150, same as the Midget 1500? If so, the water choke often sticks open, causing it to run way rich, and (if left uncorrected) causing the cat to clog, often leading to engine fires. Less traumatic, but more common, due to the carb's placement directly above the cat, would be vapour lock and hot-starting problems.

I would lean more toward correcting the root of the problem... but getting rid of the cat, if legal, does have a possible upside, with that particular engine & carb combo.

 

[Mark Jones]

Yes, the Spitfire has the same Stromberg setup and what you say is true. Also, as happened to my Spitfire, one of the screws in the carb's choke assembly can come out and drip gas onto the cat and start a fire.

Getting rid of the emission equipment does improve performance. But what made the biggest difference was to rid of the Stromberg setup and put a twin HS4 setup and heat shield on; auto choke problem solved. Now the car can actually get out of its own way.

 

[swift6]

I would lean more toward correcting the root of the problem... but getting rid of the cat, if legal, does have a possible upside, with that particular engine & carb combo.

FYI, In the US, regadless of where you live, removing a catalytic converter or any manufacturer installed emissions device is illegal. It may not be enforced but it is actually a Federal offense, not just city, county or state. Just because it is not enforced does not make it legal. Just keep that in mind when altering any emission set up.

 

[TR3driver]

FYI, In the US, regadless of where you live, removing a catalytic converter or any manufacturer installed emissions device is illegal. It may not be enforced but it is actually a Federal offense, not just city, county or state.