How smooth does a stock turbo motor run?

[flattype]

My engine idles kind of rough (many mods larger than stock cam also). I dont know if theres any stock ones left but do they ide smooth (engine not shaking back and forth too much) Mine runs really good doesnt seem to have a miss just idles a bit rough, nature of the beast? Thanks Eric

 

[1970gsx]

Broken motor/trans mounts?

 

[bison]

They dont have balance shafts in them, have offset crankpins, and are not balanced at 50% like a v-8. They are underbalanced and only are completely balanced in one plane. The rubber mounts are suppose to absorb some of the imbalance on these engines. If you feel it in the car i suggest you get a new set of GM engine mounts.

 

[Ormand]

A stock engine with a stock cam doesn't idle that well, but it's not really rough. With an aftermarket cam, they are pretty smooth, but not as smooth as a V8, or as one of the latest V6s. And like the man says, bad engine mounts will make them worse.

 

[441120]

Stock engines had a slight "rough" idle, when you look at the engine it shakes a little. A friend of mine had his engine done with bigger cam, not sure the size but pretty radical, his engine looked like it wanted to jump out of the car
He had all new mounts and all, it's just 6 cylinders making 8 cyl horsepower :biggrin:

 

[flattype]

Stock engines had a slight "rough" idle, when you look at the engine it shakes a little. A friend of mine had his engine done with bigger cam, not sure the size but pretty radical, his engine looked like it wanted to jump out of the car
He had all new mounts and all, it's just 6 cylinders making 8 cyl horsepower :biggrin:

Thanks thats what I needed to know.

 

[Ormand]

The Buick turbo 6 makes "V8" power by using lots of boost, NOT high rpm. A cam with lots of overlap is not the right cam for the turbo V6- it will make it run rough, and it will make less power than if it had a turbo cam. But as they say- whatever floats your boat.

 

[VadersV6]

Mine idled rough as hell when I bought it. Turned out it was running on 4 cylinders most of the time. Being totally pshycotic about tuning details and little odds and ends like every source of a possible vacuum leak, ignition components, fueling, exhaust leaks you cant hear but are there, sensors that are adjusted perfect and function properly, learning how to tune right, has made all the difference in the world. It idles much smoother now. It barely shakes now, wheras before it was like a harley motor running on 1 cylinder.
As far as that cam goes, if you increase duration by opening the intake valve early and increasing overlap, you are throwing alot of power in the dumpster by using that kind of cam in a forced induction motor. Increase duration by keeping the intake valve open longer...closing it later after bottom dead center. You'll get this by going with a wide lobe separation and low overlap. Big lift cams are pointless unless your heads can flow alot past stock valve lift levels....but dont memorize what we say...UNDERSTAND.

 

[Lee_Burough]

After vacuum leaks, a modern chip made the most improvement in engine idle for me in the three LC2 engined cars I've owned.

 

[flattype]

Very helpfull posts..... Anyone else?

 

[441120]

Still running stock cam :biggrin: Any replacement won't be much bigger, hope to never need one.

 

[GN owner]

The stock engine should idle smoothly. When I first bought my car the engine would not idle smoothly. The problem was traced to a defective O-ring for the #2 injector. Another problem I had was the engine would not idle smoothly and would rock from side to side periodically. This was cured when I installed another set of injectors. Apparently the set I originally had was sticky or partially clogged. The chip can make a difference so make sure that it is burned for your combo. Also insure that you don't have a flaky MAF sensor. The way I troubleshoot this is to swap it out for a known good one. Hope that helps!