This looks like a simple minor upgrade to do, but units seem rather expensive for such a minor increase in HP.

First off, is there any difference between the throttle body on a 2002 LS6 and the LS1?

I've heard rumors of idle problems with aftermarket throttle bodies. Is this an issue with particular brands?

Any brands or models best stayed away from?

Is bigger better?

When a throttle body is said to be "ported" exactly what does that mean as being different from the stock body?

Is polished the insides of the throttle body worth the effort?

Has anyone replaced their throttle body and wished they hadn't?

Thanks.

 

No difference.
Idle issues have been found to occur when the 'lip' in front of the throttle blade is malformed or decreased in size due to excessive porting.
A ported throttle body implies a stock(GM) throttle body, so that model is what most will start with. There are vendors that port and polish the stock throttle body and do a good job. If you stay stock sized I have heard good things about the Shaner.
IMHO not on a stock motor. Some have used the BBK 80mm over stock and have had good results.
The shape of the stock throttle body throat is conical in shape. When one is ported the shape is changed to more of a bell to admit more air at the mouth and try to increase it's velocity as it passes the throttle blade more like a velocity stack.
Not really, but some of the castings in the throat are really nasty and cleaning them up will have a very slight effect on turbulence. Not sure if it is significant enough to help overall performance but it looks nice.
The $64 question. I ported and polished mine and although I don't believe I gained that much, 3-5hp, and made my idle transitions a little flakier, I am glad I did it, although I don't think I would have paid for one to be done for me. Throttle response did improve and although the SOTP was inconclusive, I like to think it helped. And while I was at it, I polished the outside of the tb and it made my motor look a little better.

 

From what I've seen going with a 90 mm TB and LSX intake manifold doesn't seem to be worth it - although I'm tempted. I haven't found any good dyno comparisons yet.

There is an interesting article in the March issue of Corvette Fever - installed a 78 mm Callaway billet TB on a 2000 FRC with head/cam, headers and honker intake already installed. Base line: 419.2 rwp, 393.3 rwt.

After the Callaway TB install: 224.2 rwp, 402.2 rwt. The big improvement was in the torque numbers at low rpms.

I would expect about the same from the other 78-80 mm aftermarket billet TBs, maybe a little less from the stock ported TB.

 

IF YOU WENT WITH BIG HEADS AN A CAM THEN I WOULD GO WITH A 90/90 FAST INTAKE. DO NOT FORGET THE HADERS. THEN IT SHOULD BE FINE.

 

I ported and polished mine myself and I think it helped quite a bit.