Thread: Valvetrain tuning ?

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+Advancing the cam on first install
+Higher Ratio Rocker arms for more lift
+Adjusting the lash (tighten or loosen) to advance the Valve opening

I will be doing some valvetrain work on my 383 stroker soon. my cams has a max lift just under .50 and is a very "streetable" cam. my questions are...

...How will these changes affect my overall power curve. my understanding is that most will hurt my low end power. but will "greatly" increase my high rpm power.

...Any comments or concerns i should have before doing this.Is it even worth it and will the changes be noticeable.

... this car will be a weekend warrior with only a few visits to the strip

get the right cam off the bat then there not much need playing with much of this stuff i used 600+ LIFT on the street you can play with some of this stuff but for the street you may not see a big gain in it .you valve springs and rocker guid slots in heads if no guids must be checked for a bigger rocker .push rods will need to be the right length at mid lift if lets say you have stamp rockers to a roller or different make of rocker arm so new push rods as well when moving a rocker swap. moving the cam your going to need to get at the cam EZ so you a front cover that can do that . as well as taking the front off the engine every time . piston to valve will need to be checked as well as the cam will not hit rods as this is a 383 rods do come in to play. a gear set that will lt you move it 2 at a time and you will need to know were cam is now .there is lot of things to play with before working on this stuff you can do .take to much lash away and you can over heat the valves and cup them . rods can hit on the cam if not check when cam is moved running the engine on a dyno could he you weed threw some of this

I would agree 100% with what Pat has said and will add a few other comments---

First with a close to stock cam for a street driven car, none of this will result in much change--you will need to get upwards upper .600-800 lift cam before you need to start to do this---First off you have to check for camshaft/connecting rod clearance for several degrees advance/retard from straight up timing( so you will know the limits of advancing /retarding cam) And to do this on an assembled engine in a car pretty much gets you to the point that a Jessel belt drive with the long water pump is needed--also any cam advancining/retard necesstates an reset of the ignition timing(unless crank trigger)
Heads, springs,valves,lash caps, guide plates/slots/rocker alignment--all need to be set up for the lift of the cam plus checking for valve /piston clearance at advance/retard limits
Changing valve lash is pretty much limited to a thou or 2 because of limits of cam lash ramps and types of cylinder head/block materials(alum-iron)
Rocker ratios should be utilised that are highest ratios possible