Finished the new motor install.

My #5 and #6 cylinders had red hot primaries after 30 mins of idling at 2000 rpm.

Its a 383 btw and I have no cats.

Any ideas?

 

Just occurred to me, I forgot to tell the engine builder that these were comp R lifters.

Could an overtightened intake or exhaust valve causing a lean condition?

 

Fixed it.

For anyone else having this problem, the rockers were too tight.

New engine and the engine builder tightened the rockers down to zero lash but once the engine fired up, the lifters pumped up and kept the exhaust valves open.

Resulted in a poor idle as well.

Took me 1.5 hrs to jack up the car, disconnect the alt, re-lash all the valves to finger tight, lock them, re-assemble the car and put it on the ground.

 

Glad to hear you got it fixed...

Just out of curiosity, why did you need to jack up the car to work on the vavle lash? I would think that would make it harder, or maybe it's just me, I hate reaching into the engine bay with it up on ramps...

 

I had to turn the crank with a torque wrench to put every cylinder at TDC when I lashed it.

 

Oh yeah I forgot about that step... I am planning on installing RR's in a few weeks so I guess I should have remebered that

 

Why not just set it while the engine is running? Thats how i was taught to do it.

 

Ouch. A remote starter would work 10x faster...or unplug the coil wire and do it from inside the car.

Mike

 

So many people to help me crank over the engine but no one to tell me I had to re-lash the valves lol.

Didn't occur to me at the time to disconnect the coil.

 

were you getting any backfires out the intake and low vaccuum? See my idle is "ok" but if I blip throttle i get a backfire out intake and the motor is running lean and I have low vaccuum

 

Do you still have cats?

I had none of those symptoms.

CHeck to make sure your plug wires are wired up correctly.