IMO like I did once your gonna put new springs and lifters on the heads get some new ones like 243s are a good choice or mill them a bit. And for intake id recommend the tbss/nnbs intake manifold.

 

sorry bud again im a back yard guy lol...wats imo tbss/nnbs? Sorry man im new to the ls world...better with carbs haha

 

No worries man Tbss = trailblazer ss . Nnbs = newer body style silverados the 07-12. Id highly recommend one of those manifolds they work great on 2000-2006 trucks you can pick one up on here for a decent price of 300 with the 87mm throttle body that come on them which is way better than the 78mm ones that come on the trucks stock. It'll help that baby breathe much better

 

Awesome thank u

 

Is it still possible or good to put a throttle body spacer on even if i get the nbss/tbss intake and you say its a 87mmhuge but all i can find are 80,85,90mm

 

On the throttle body spacer I personally wouldn't run it because I've heard there just a waste of money? And the 87mm throttle bodys came on the truck manifolds so for say if someones selling a nnbs manifold and it comes with the TB it'd end up being a 87. If its off a tbss those came with the 90mm. Heck id reccommend if you could do a 90mm it be better

 

https://www.performancetrucks.net/fo...%24200-513410/

There was a thread on here of a person that put one on and dyno proved it to give about 15 or more HP which is pretty good.

 

It was only 07-12 that they came on....just i looked for after market and theres nothing haha

 

07-12 for the silverados n I think the same year tahoes come with it to. For after market checkout FAST (fuel air spark technology) they have some good quality ones. Were you gonna run a bigger throttle body bro?

 

your better off going with a TBSS or NNBS intake over the fas... its not worth the money IMO