whats the advantages or dis advantages of advancing the chain

Say instead of setting the timming chain at 0 I was to set it at 4* advance what would be the probulems it would creat and or what would be the advantages of it??
I know this is an open fielded post.. but lets see.. the probs the guy is having is it won't idel very well and it has a stall when he steps on it eather from a stop or when moving slowly ( I told him sounds like accelator pump but with all the other issues he is having I'm not sure).. With the way he has it set up in "N" its Idling at 1500rpm.. Would the timming chain set at 4* advance cause it to be realy lopy at a normal idle...
Thanks
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Advancing a cam will increase the low end and take some off the top. Not a lot, but some. If anything, it should help the idle. Problem sounds more like a huge vacuum leak.
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Thanks Ckelly
Thats kind of what I was thinking ... Vacuum leak...
I'll pass it on..
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