what next?

Hello...i've got  '05 z-71 with a 5.3 in it....so far i've added a K n N cold air kit (cold air box and tube), JBA headers, flowmaster force 2 exhaust, MSD wires, and superchip's programer (running 91 octane performance mode).  i'm wondering what is next on the fairly simple but above bolt-on power adders are next in my quest for power.  i'm not looking to get boost or spray...or anything that's going to require havint the engine sripped (ie- cam) . i was thinking of looking around for a intake manifold or maybe a under drive pulley system.. any suggestions? i've seen or heard of people running different ratio rockers...anyone know of that?

curiously, how's that superchip doing for you? I'm looking at getting a tuned PCM from Nelson Performance 

Not sure if you have e-fans being you got an 05 but that along with adding a e water pump would free up some ponies .

Also, I?m running the ASP underdrive pulley.  If you go this route, you need to beef up your ALT

what about a transgo shift kit?

don't really need a shift kit due to the ability to change the shift firmness with the superchips programmer. i'm looking more into a throttle body spacer.  as for the fans...i've already got a pair of electric fans so the water pump i don' t think is taking that much power as far as the ost per HP goes.  who knows...maybe i'll just drop a 75 shot of NOS on it lol

95highline said:

don't really need a shift kit due to the ability to change the shift firmness with the superchips programmer. i'm looking more into a throttle body spacer.  as for the fans...i've already got a pair of electric fans so the water pump i don' t think is taking that much power as far as the ost per HP goes.  who knows...maybe i'll just drop a 75 shot of NOS on it lol

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all a throttle body spacer does is make noise

well...some time has passed and more thought into what next for my mods...i don't wanna put to many aftermaket parts into the engine because it's still under warrenty and if i blow the bottom end i can see huge dollars dissapearing (cam, higher compression pistons, etc) so i'm thinking getting a set of stock heads and giving them a PnP job along with a 5 angle valve job and then following them up with a set of SLP 1.8 ratio rockers.  i'm wondering if what kind of gains i could expect or weither it's worth while as i've been told the 5.3 heads are a good flowing head to start with.  I am also wondering what stock head would be a good replacement over the ones i currently have same with intake manifolds.  I don't want to make HP in the high RPM but i would like to keep the max HP in the mid range RPM.  My engine is a 5.3  "t" code i beleive

That valve job and those rockers will entirely void your engine warranty, likely the transmission and front/rear ends as well.

If you're concerned since you still have a warranty, you need to stop messing around with it, seriously.  If you encounter a problem as it is now, you need to put a stock tune back on there.

let me change something...i'm not overly concerned with the warrenty as far as it goes. it's just if i the engine ends of blowing they usually replace the least amount of parts  as needed. so most likely they would re-use the heads and intake befor they re-use the cam or connecting rods. plus with useing stock parts (stock ported heads) it's also not as obvious.

To open it up/replace heads, they're gonna find the rockers.

They'll find evidence of the head swap as well.

Very simply, that warranty on the engine is toast the moment you put those items in, and you're ricking trans and drivetrain.

So you need to decide, since you've now stated it both ways, you care about the warranty and you don't care about the warranty.

ok, lets assume i forget the warrenty and drop a set of ported heads  with the rockers. what would be the best stock design head and would it really be worth the effort for the HP produced?

95highline said:

ok, lets assume i forget the warrenty and drop a set of ported heads  with the rockers. what would be the best stock design head and would it really be worth the effort for the HP produced?

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No.  stock 5.3 heads flow fine.