Snorkelface

I finally got the car started, but I'm have a hard time determining if it's running on all 8 cylinders.

This was the first start after the car has been sitting for 4 years. I changed the oil, new cap& rotor, and new spark plugs. I just want to make sure it's right before putting the turbo exhaust back in as I have to pull it to get to the plugs. Can anyone listen to this and determine that? I can get the cam specs if needed in the morning.

Thank you!

Snorkelface

The cam is an Ultradyne CHS290/290-14NR, 232/232@.050.

Could anyone give a listen to the attachment in the first message and give feedback? Or, is there some other way I can verify that all are firing?

hrcslam

Take an ir thermometer and measure the header temps at each cylinder ($15 at Harbor Frieght or Lowes). They should all be hot (200+°F). You'll want to do this anyway to adjust your individual fuel injector trims in the tune for idle and part throttle. You want them all to be as close as possible.

Snorkelface

Ah, that's a great idea! I'll go pick one of those up. The headers getting warm in general world at least tell me whether it's firing.

Second question: Do I risk damaging anything by running just the headers while it's sitting and idling? I don't want to put all the turbo piping back in under the car until I know everything is working in the motor and I won't need to get to the plugs or plug wires again.

hrcslam

Long tube headers? Possibly. Usually it's not a problem, but depends on how good your tune is and if you keep it in open loop. It may run very very rich in closed loop.

Turbo manifolds? Yes. It can very well melt your valves.

Snorkelface

I have a turbo, but they're like mid length. It sounded like they were all firing, so I hooked up the piping. Thanks for the info!

hrcslam

The answer I gave has to do with how the exhaust flows. Without a full exhaust behind the turbo manifolds the exhaust wont scavenge. That causes the hot air to linger. Long tubes don't have that issue because of how they flow (you can run these open with a proper tune and never harm the engine). Anything else needs at least the Y-Pipe.

SS RRR

iTrader: (2)

No, because of the cam that thing is basically firing cylinders at a time when idling. Bring the RPM up 1500 to 2000 and then try and listen. The other thing you can do is if you can get it to keep idling, pull one injector off at a time and see if the idle changes.

Snorkelface

Arrange, thank you for the tips and the information guys!