absence of emissions equipment?

[bandoni]

Hi all i noticed on my 78 280z that all the emissions equipment has been removed ie cat converter, air pump, and diverted valve. my question is will the absence of these components make my z run better or worse?

[beandip]

The air pump being removed wont make any difference , other than eliminating the resistance to turn the pump. The other things being removed should result in a HP gain as the engine should run better. However you will not be able to pass emissions testing. It all depends on tuning. I have a couple of friends that have eliminated almost all of the sensors and emission related equipment on there 280s and they run vary well. I believe one, one a 79ZX passed emission testing also. I think he is still running a cat. though. the computers were modified in some way though. Gary

[bandoni]

The air pump being removed wont make any difference , other than eliminating the resistance to turn the pump. The other things being removed should result in a HP gain as the engine should run better. However you will not be able to pass emissions testing. It all depends on tuning. I have a couple of friends that have eliminated almost all of the sensors and emission related equipment on there 280s and they run vary well. I believe one, one a 79ZX passed emission testing also. I think he is still running a cat. though. the computers were modified in some way though. Gary

oh i don't have to worry about it passing emissions since i don't have emissions in my county. it's good to know that it is not harming anything though.

[Arne]

No harm to the car, but I seriously doubt that there is any real performance improvement on an otherwise stock L28. That being the case, it might be better for the environment to plan to re-install at least the converter.

Just my opinion, others may disagree.

[e_racer1999]

No harm to the car, but I seriously doubt that there is any real performance improvement on an otherwise stock L28. That being the case, it might be better for the environment to plan to re-install at least the converter.

Just my opinion, others may disagree.

agreed

[bandoni]

No harm to the car, but I seriously doubt that there is any real performance improvement on an otherwise stock L28. That being the case, it might be better for the environment to plan to re-install at least the converter.

Just my opinion, others may disagree.

it's not exactly stock, it has a k&n cai, headers, exhaust, and according to the previous owner a upgraded cam. but i take that as a grain of salt as theres no proof towards it.

[Walter Moore]

It is common in areas where there is no mandatory emission testing for people to remove the emission control stuff in an attempt to improve performance.

I suspect that it does improve the performance somewhat, if done correctly, but remember that it is still illegal.

There has been talk from time to time about setting up remote air pollution monitors along interstate entrance ramps, sort of like photo radar traps, to catch people with seriously excessive emissions. I know that putting all that stuff back on would be expensive, and a hassle.

[sblake01]

78 280Z's don't have air pumps. Only the California cars had cats. I don't have a clue what a 'diverted valve' is.

[Tony D]

Chances are you didn't gain anything at WOT (peak power) since every single device you mentioned has absolutely nothing going on at 'full power' levels on the engine i.e. "Wide Open Throttle".

Actually, chances are good the only thing accomplished was increasing emissions drastically at partial throttle and cruise conditions, where the engine spends most of it's time anyway.

Unless the engine has the fuel curves reworked, removing the emissions equipment will do nothing for WOT performance. It's the fuel delivereed compared to the air ingested that makes power. The remover of the devices didn't do anything substantial enough to increas airflow, nor fuel flow, so no more power will be had.

I dynoed my car before and after a CAI kit, and compared with a K&N filter in the stock box, I could not quantify any power gain whatsoever on back-to-back series of three runs within 20 minutes on a Mustang Dyno.

I think the restriction of the element is what gives you power, and it's the differential between the stock paper element and the K&N gauze element that gives the power anybody sees from a CAI. Hell, the 280Z already has an air cleaner in the same spot as the CAI filter---it's already got CAI! As long as that black snorkle-muffler thing is not on the inlet to the stock filter box!