So i searched around and couldnt find anything that quite fit my problem.

i have a 1982 280zx na m/t. i have just installed a new set of MSA 3-2 headers, and the msa exhaust from thezstore.com and everything seems to be running fine. however, i feel like it has more torque when not under hard acceleration. the car with the windows closed and the tops on smells like exhaust with a powerful scent of unburned fuel. i dont know what the cause of this is.

the fuel filter is new, there is no fuel leaks in any of the lines, the injectors are working great, the intake/exhaust gasket and the valve cover gasket are brand new.

i have adjusted the valves (which were tight) and seems to run well now but i fear it may be running rich because of the smell and the power. is it worth it to clean the silicone out of the idle fuel/air ratio adjustment screw and try there?

to be clear- the car is neither faster nor slower with the new headers and exhaust installed. there has been no change in power, except that the powerband seems to have moved north and it seems to have better torque while driving conservatively.

is there anything you guys might know about these cars that might help me adjust it and get better power? should i have expected any power increase with these headers/exhaust?

 

From this thread yesterday: https://www.zdriver.com/forums/280zx...ng-cams-35232/

Most performance upgrades do minimal "upgrading" by themselves. In combination with other upgrades, they can have a major effect.

So you installed a less restricting exhaust... but didn't do anything to the intake, so it's virtually still the same voume of air flowing through the motor, just a different pressure coming out.

As for the exhaust smell, are you still running a cat?

 

no, no cat. straight through. but do all z's have lethargic acceleration when under full throttle? i mean, it isan n/a, but my 0-60 time is 12.4 seconds instead of the stock 9~ seconds.

 

The lack of a cat is the reason. We had a lengthy discussion about it here: https://www.zdriver.com/forums/280zx...hickens-34206/

As for the lack of power...

Have you checked your timing?
Spark plugs? (and read the plugs?)
Wires?
Sensors and connections? (AFM & CHTS are the main ones)
Compression check?

The stock n/a should still pull pretty good up to 4500-5000 rpm... nothing like the turbo though.

 

have you checked the carbon canister to see if fuel is coming out of there?

 

Problem solved. my timing was advanced about 14 degrees too far.

new problem. i ran to the drag strip with it for giggles on friday night. everything ran fine, and near the end of the night, while waiting for them to clean the track, (a awd truck broke his front axle which sheared off the oil filter, spraying oil 1000ft down the track) i shut the engine off and went to hang out.

when i came back, i turned the engine on, which worked fine, but none of my interior lights would turn on, the engine bay light wouldn't turn on, the warning light, no dash lights and the tachometer would not operate. my speedometer has never worked, so no news there. the car ran fine, drove it home and turned it off in the garage, vowing to take a look at it the next day, thinking it was a fuse.

the only fuse that was fried was the horn relay/inspection light fuse. so i replaced that, went to turn the car on, and lo and behold, it has trouble starting, once started it bogs hard when you try to rev it, and when it does rev, the interior lights get super bright, the tach moves, but not following the actual rpm sound, and a high pitch whine comes through the stereo speakers, which is off. (could be coming through the "lights are on" voice box though, i didnt check exactly where the sound is coming from.)

the alternator and battery are new. the battery is very new, and the alternator is a napa rebuild, less than 2 months old, and probably 30 miles on it.

 

Sounds like you have a bleed in your wiring. Electrical can be so fun. lol Time to get out the wiring diagrams, and start troubleshooting. I did fix my power mirrors last night. Turned out to be my switches were burned out. So that is one more thing that is fixed electrical wise in my Z. More to go. lol