git_sum

iTrader: (10)

Ok i need some advice as to what i need to do with my heads and valvetrain. I recently purchased a stock set of 5.3 liter heads (casting #862) and i have a TSP228R cam, TSP chromoly 7.4 pushrods, ported ls6 oilpump, rollermaster double timing chain set, and Patriot Gold spring kit. I'm also gonna buy a new set of comp lifters and arp head studs. All of this is going in a 99 A4 Trans-am with 84,000miles.

I need to know what size intake and exhaust valves i should run with my cam. I thought about going 2.055/1.60 but i've read that the 2.055 valves will be to big for a stock displacement engine and that i should use 2.02's instead. Does anybody know anything about this? Also i don't know if it matters but i plan on running a 100hp wet shot of nitrious down the road.

Second of all what else am i gonna need to go with the heads since i'm basically starting from scratch. I've heard i have to change the exhaust valve seats. Where do i get those and what's the best ones to use? Also should i go with an aftermarket rocker arm, and what brand would you suggest for my application?

What would you guys suggest for the buildup? Any and all advice will be appreciated and taken into consideration.

66deuce

iTrader: (1)

if it was me,i would go with 2.02 int. 1.57 exh.,then you don't have to change the seats.if your heads have a lot of miles on them,you will probably need new valve guides.loose guides will rob you of power and can lead to a broken valve especially if your going to pound on the motor,as most of us do.i would stick with the stock style rocker arm,IMO the power gains don't justify the money spent.

git_sum

iTrader: (10)

So if i went with the 1.60 exhaust i'd have to change the seats? Wouldn't it be better to use the bigger exhaust valve since i'm gonna run the nitrious later?

git_sum

iTrader: (10)

Where can i buy new vavle seats and guides?