ive been hearing that the more horsepower i try to get out of my 350, the worse its going to idle. what exactly makes for this poor idle?

 

That all depends on what you do to the engine. What you're referring to is a rough idle being a by-product of a radical cam. If you leave the cam alone and do other enhancements, you're not going to get that type of an idle. But some of us like a rough (poor, lumpy) idle! And you can get cams that will give better performance, yet still retain a fairly normal idle.

 

If you find a cam with the highest lift, but shortest duration you can find, then you'll get good power at the low end, and mid range. You'll also retain a good smooth idle, and only suffer a bit on the very high rpm range.
Like Camaro 69 said, some of us love the sound and feel of a big lumpy cam!

 

I don't know who told you that but tell the that the ZR1 makes 632hp and purrs like a kitten. Again its all in the cam.

 

A rough idle is more a result of overlap than anything else. You can spread the LSA with a big profile and still get a decently smooth idle, but what's the point? If hardware isn't falling off from vibration, it's not a hotrod.

 

Yup the LSA on a Vette is probably around 117* vs the 110* on the cam in my 383.

 

The cam in my 427 is 114 degree separation, and although it's 284/284 .528" lift, it idles pretty smooth and still makes great HP. The one I'm putting in the Austin's 327 is 234/234 at .50, advertised duration 292/292, with .488 lift and 114 sep. I'm using 1.6 roller rockers so the end lift should be over .500". Hopefully it will be nice and lopey!

 

I now have a SB 427 in my 77 with a 650 lift, 260/266 at 50 cam on a 108 LSA. It is my work car on most days, and on weekends I shoe it with Hoosier Quick Time Pros, drive 10 miles to the track, race it, and drive 10 miles home. I'm not trying to jack this thread or pat myself on the back, but am emphasizing that things can get pretty gnarly in the cam department and still be tolerable, depending on the sanity of the driver.

 

Well that all seems pretty logical. Thanks.

By the way I love the car1971bb427! I especially love the color! My body shop guy is welding on a new roof pannel for me and then all the body work will b done for my 70. I was thinking cortez silver with the black stripes but I really can't decide. How did you decide? Have any suggestions?

 

the cam in my 468 is 112 LSA with 248/248 @.50, 285/285 adv dur, and .660 lift. I have 1.8 roller rockers and it has a nice lope to it but its not super rough and still pulls good vacuum