I have an L05 350 that I swapped from TBI to carburetor. It is an edelbrock 1406. Ever since I did the swap, however, my engine has been running at 4K RPM at idle in park gear. I made sure the gaskets are al completely sealed, there are no gaps whatsoever, but I’m still getting bluish smoke out of the exhaust and high rpm’s. What’s going on?

 

Well:

This means that your "tach" (pointer-wavy thing in the dash) reads about 4 times what the engine is running at. I'd bet it pegs the instant you touch the gas pedal too. Not to worry, it's garbage like just about all the rest of those "sporty trim packages" in these cars. They weren't accurate to begin with when they were new, and they all fail just like yours, EVERY ONE OF EM, by reading WWWWWWWWAAAAAAAAAAYYYYYYYYYYY high. Ignore it and pay attention to some actual test equipment instead. When you get an actual believable measurement, adjust your car accordingly.

Valve guide seals most likely. Same as every other high-mile small block Chevy. Change em out. Not hard, not $$$, just do it.

 

Is there any way to do the valve seals without pulling the heads? Also it’s an aftermarket tach hooked up to the distributore itself, so I think it’s reading right.

 

Does the engine sound like it's revving 4k RPM?

The aftermarket tach is probably set for 4 cylinder mode but a 2k idle would be to high too.

 

Of course. About 90% of all valve guide seals are installed with the heads in the car. (speaking strictly for myself) Quite simple really. Once you get past the "it's hard" and "I didn't think you could do that" CRAP we'll be happy to help you out with it. Any idiot, EVEN ME, can do it; so I'm sure somebody [forrest_gump]smaaaarrrrrt[/forrest_gump] like you can do it too. Probably twice as fast as I can.

I think IT'S NOT.

A L05 sitting in Park or Neutral with the throttle WIDE EFFFFING OPEN will barely do 4k. I think either it's defective or it's set up wrong. Especially if it PEGS the instant you actually hit the throttle. If it idles at 4k, and you go to take off from a stop, should read AT LEAST 7000, if not more. Altogether impossible for a TBI motor. Which you didn't mention that, leading me to suspect that ... maybe ... it does.

 

yes. when it was idling with the TBI on it was reading around 900, and it was relatively quiet. as of right now its super loud from both the engine itself and the exhaust.