Valvetrain question.

Ok so i just put a set of gtp heads on my 89 gt. :nice:While a had it apart i went ahead and installed an e303 cam(stock rockers(100k miles) and pushrods). When i fired it up it ran and idles fine but it sounds like someone is tapping on the valve cover with a hammer. :notnice:I removed the v.c. and rechecked the torque specs on them(25 ft/lbs) but the problem persisted. Whats the deal. The noise dissappears after about 2500rpm(dunno if it goes away or i just cant hear it over exhaust) do these heads require longer pushrods? are my lifters not pumping up? little help would be great.
thanks
-saphirestang89
 
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the torque specs on the valve covers is 25 right? b/c if you meant rockers, then i'm pretty sure they're measured in in/lbs (that's the voice of experience talking from when my friend snapped off three RR boldts! ha!)

um, is the noise in one spot or all over?
 
One way to figure that out is remove your valve cover and verifiy oil is coming out of all of the rockers. If you see oil coming from all but one rocker then its a bad lifter not pumping oil. For this you might want to place rags on the manifolds and dont rev the engine just let it idle.

getas a little messy if you rev it.
 
with reusing old parts, especially valve train parts, you want to put them back in the same way they came out. did you make sure not to turn any of them around or put them back in the same order?

I would think its a lifter not doing its job. But you described the noise as a hammering... bad lifters/rockers should sound more like a tapping no? And they would def be harder to hear with the engine at higher RPMs, so it is one of your valve T parts over there...
 
ummm I know they say toque everything to spec but those should be self adjusting rockers. When I had those I always just snugged them down tight and never had a problem. Sounds like a bad lifter or bent pushrod. I would replace them all if it a bad lifter, so you dont have to keep taking the intake off. Would save money in the long run. Replace the pushrods too they are cheap and a good investment.