bad accerlation why?
 

ok whenever the car is still cool it accerlates pretty good. but after driving it some distance it like tightens up and doesnt accerlerate that good. anyone have a problem like this. its an 87 na with an intake and hollowed cats and 5th & 6th ports tied down.

I have the same problem and thought a lot about it. I concluded that there can be various reasons. First is the air-fuel ratio, this is probably to lean when the engine is hot. (When the engine is cold the computer makes the air-fuel richer) Air-fuel ratio is (among others) controlled by the O2 sensor and TPS (so replace the O2-sensor and adjust you're TPS). I've did that but didn't notice much difference

- Another reason could be bad compression which could be worse on a hot engine than a cold engine (because of the heat the parts differ in size) Just today I bought a bottle ATF and I got a set of old spark-plugs ready so I'm gonna give the ATF-trick a try soon. ( Just waiting for a foggy day to keep the neighbours from complaning)

- Yet an other reason could be clogged cats, i don't know why but I notice the differ in acceleration much less now I have gutted my pre-cats. I did notice an overall performance gain though.

- Vacuum leak. I sprayed varnish-based anti-moist all over the intake and tubing hoping to cure vacuum-leaks (not sure if there were any, but just in case) and this also seemed to make a big difference in power.

( All this is why I like my car so much, I can experiment with it and I understand what I'm doing and how it works. )

Marco.