Hi Everyone, Ive spent many many hours/days researching with the result of lots of knowledge but still no prevail to a solid plan. Sorry if some of this is repetitive but I am looking for a straight forward answer. I have also read all of the Sticky's for knowledge as well. Anyways its winter and I want to make the car a little funner for this coming summer.

I have a 2000 T/A LS1 M6. Im assuming I have the 241 heads but I havent verified that yet so they may be the 853's or whatever the earlier heads were.

My goal is to make 400hp or close to it, im not going to be bummed if it only makes 385 or 390 but that 400hp would be awesome!!! I do want to keep this on a budget but the funds are available if I need to spend them... I only want to make 400Horse not 500+ and the 400 sounds pretty easily attainable on a small budget. This will be my summer daily driver as I cannot resist driving it compared to driving my Grand Prix GT. So I want to keep it very streetable with the decent fuel mileage I already get out of it (28-30 mpg highway) I know its a muscle machine and fuel mileage really is not my concern but it sure is nice if I can maintain it.

Currently the car has a
-Borla (tuneable) cat back
-Lid
-the rest is stock except for the Tick Master and clutch.

Planned already is(awaiting purchase/install):
-LS6 Intake
-Ported/polished stock Throttle body
-Long tube headers
-Cat less Y-pipe most likely 2.5"
-A dyno tune by a reputable shop

Above is my original plan but I really want close to that 400hp and if I do the above and go through all the time for the tune and can only get 350hp or so out of it im gonna be bummed and wish I did cam/heads as well and I will end up doing that and go through the whole tuning process again which why do things twice.

So I have been doing lots of research and sounds like my above plans may not quite get me to or close to the 400hp OR WILL IT??? (please answer)

So to get me there it will be heads and Cam to add to the above power adders. When I bought the car I really wanted to leave it unmolested and leave it factory but that idea fizzled out. But Like I said above I want to keep it street and daily driver friendly. I dont want to mess around with surging and bucking while just cruising or hard starts and not looking for a hugely choppy idle. Id like to maintain the 800rpm idle and be able to cruise the parking lot with little hassle. I dont want to regret my cam choice with wishing that I wouldve went bigger or regret that I wish I wouldve went smaller. Ive listened to youtube videos and sounds like the Torquer 2 is real popular and streetable and honestly that one is almost too choppy at idle for me but I know that there would NOT be one day that I would hate it either. So is this what everyone would suggest for a cam to attain my 400hp goal (with the above add ons and heads if need be)??? (please answer) or is there another cam out there that may not be quite as choppy that will easily get me to my goal (tick performance, comp cams, speed shop cams)???

Next would be heads:
will my stock heads with the cam and above add ons get me to the 400 hp range?? (please answer) Or should I upgrade. I do not want to spend $1200+ on heads... the most im willing to pay is $500 on heads whether that is on some 243's or a port and polish on the ones that came with the car. But why spend the money if the ones already on it will get me to the 400hp mark. But I would hate to already be so far into dissassembly and get it together and to the dyno and I only pull 360hp out of it and if I wouldve done heads then I would have hit the 400Hp mark. So which direction should I go with the not any more than $500 budget for heads? (please answer) Should I purchase 243's since they are going quite cheap and possibly port and polish those? or should I take my 241's (assuming) and port and polish those?? or should I just leave the heads alone all together and be confident that with the cam and above power adders that I will hit the 400hp mark?? (or close to it)

When do the cam I will be doing springs and push rods with the knowledge that the factory ones are just barely sufficient for factory components.

My plan was Beehive springs and just hardened push rods.

Lets say I went with that Torquer 2 cam would I have to change lifters or rockers? Are the push rods going to have to be a different length from the factory push rods... I know These are questions I can ask Texas Speed but maybe someone knows off the top of their head???

So to get my 400 Horse what out of all the stuff above is needed and not needed or is it perfect? What brand/size springs would you suggest?

So will this list get me to the 400hp?
-LS6 Intake
-Ported/polished stock Throttle body
-Long tube headers
-Cat less Y-pipe most likely 2.5"
-A dyno tune by a reputable shop
-Lid
-Cat back Borla
*im assuming not so will the addition of a cam (torquer 2 or other suggestions) get me there?
*or will I need the heads too to get me there??? If so what do you all suggest I do with the heads... Port/Polish my stock ones on the car? Get 243's or will I have to port polish those as well? Any other suggestion for heads that isnt far off from $500 budget for heads? or will my 241's or the 243's get the job done?

-Will I need to do a cam to hit my goal?
-Will I need heads with the cam to hit my goal or will stock heads do it?
-Is the torquer 2 the most suggested cam for what I want (not too choppy, easily streetable/parking lots/daily driver, maintain fuel mileage, 400HP) or is there another off the shelf cam that will better suit my needs and hit that 400hp?
-I will do all the work myself
-Daily driver, will prob never see the drag strip and if so just on a Street legal Wed. night but prob. not but may see a pull here and there if some hot shot wants to test a F-body or if I just have the need for speed.

Thank you for the help everyone!!