302 H.o. Efi Valve Adjustment W/1.6 Rockers?

DM87GT

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Jun 17, 2014
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Hello, Can anyone tell me if there is a valve adjustment on GT40P heads I recently installed on my 302? My 302 is a H.O. engine with fuel injection. I was told there is no valve adjustment because my heads are the pedestal mount type. Was told to torque the nut on the 1.6 rocker arm down to 23-25 ft. lbs. Nothing else is needed. I was told that the roller lifter has to be seated on the flat spot on the cam, then torque the rocker arm nut to it's required torque. Is this information correct or what is the proper method to do the above mentioned? Any help is greatly appreciated. Thank you
 
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Doesn't matter about being on the flat side of the cam. If they're pedestal mount, there is no possible adjustment. Crank em to 25 ft/lbs and that's it.

Ouch, some bad advise there. Yes pedestal mounts need to be adjusted properly. The main difference bewtween them and stud mount is they use shims to achieve proper preload, swipe and height. Follow the rocker manufacturer's installation instructions for preload and torque.

For example, here is Crane's installation

http://www.cranecams.com/uploads/instructions/453e_.pdf
 
He's swapping to gt40s, not building 3000 horse drag motor. Might as well stick a plate in the lifter valley, put 4 bolt mains in it, main girdle and fill it with cement. Crank em to 25 ft/lbs. Done it with several cam and head swaps. Including exactly what your doing. Especially when you probably won't even see 6200, which is only 3600 for the valve train. I twisted my set up to 7000. On a full rebuild in my garage. People tend to over kill with small horse engine builds.
 
He's swapping to gt40s, not building 3000 horse drag motor. Might as well stick a plate in the lifter valley, put 4 bolt mains in it, main girdle and fill it with cement. Crank em to 25 ft/lbs. Done it with several cam and head swaps. Including exactly what your doing. Especially when you probably won't even see 6200, which is only 3600 for the valve train. I twisted my set up to 7000. On a full rebuild in my garage. People tend to over kill with small horse engine builds.

With that mind set. Why even bother to torque the heads, or install all of the intake bolts? I mean....it's just a junk 302, right? You don't need to build a 3,000-horsepower race engine in order to use your head! He's not talking about factory stamped steel rockers here. You can't just randomly crank down a set of aftermarket roller rockers and call it a day....you gotta measure. All heads, rockers, pushrods and gaskets are not created equal. Throw a little wear in there, a new valve job, or a decking for trueness and you could see as much as .060-.080 between valve heights.

Throw them on without measuring and you could end up with the roller tip out of the centreline of the valve....causing excessive valvetrain wear and movement.

Worse still...you may end up with ether too much, or not enough lifter pleload. That'll leave ya with valve train noise, missing RPM, lost horsepower, or in worst case a bent pushrods, or piston to valve contact.

Don't just crank em down....measure them up and use the shims if need be!!! Go out and buy a $10 set of feeler gauges and put them to work. Don't be "that guy".
 
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Michael Yount’s valve adjustment procedure

Here's an easy way to determine this. Start with the #1 cylinder. Rotate the engine with a ratchet on the crank bolt clockwise. Watch the #1 pushrods. First the exhaust pushrod will rise and fall signaling what would be the exhaust valve opening and closing if the rocker were on. As it closes the intake pushrod will rise -- keep rotating clockwise until the intake pushrod falls and is level with the exhaust pushrod - both at the same height. Both lifters are now on the base circle of the cam - both valves would be closed if the rockers were on.

Now, install both rockers. Tighten the bolts with one hand while rocking the rocker with the other hand - continue until you reach the point where you can't 'rock' the rocker any more because there's no gap on the valve stem end or the pushrod end. You are at zero lash - i.e. - no gaps. Stop tightening just as you reach this point.

Now, put your torque wrench on the bolt and tighten it to 18-20 ft-lbs while counting the number of turns it takes to reach the torque. You should hit the torque within 1/4 to 1 turn of the bolt. If it takes more than 1 turn, use a shim to raise the rocker -- each .030" shim will reduce the number of turns to torque by about 1/4 turn. If you reach the torque in less than a 1/4 turn, or you have trouble reaching zero lash even at full torque, then you'll either need longer pushrods, or to CAREFULLY remove some material from the bottom of the rocker fulcrum. Using the procedure described above, you will work through the remaining 7 pairs of rockers. If you follow the firing order, it will minimize the manual cranking you have to do to get the lifters on the base circle of the cam prior to installation of the next pair.

When I first went through mine, 13 of them took no shims; 3 of them took 1 .030" shim. Upon cranking it up, one or two of them sounded a bit noisier than I thought was right, so with the engine hot, I pulled the upper off, and the valve covers, and went through the installation procedure again. That time, 11 of them took no shims; 4 of them took one .030", and one of them took one .060" shim. And they were very quiet running.

Good luck with it.
__________________
Michael Yount - K'ville,TN 82 Volvo 242w/5.0L; 2000 Suzuki Bandit 1200
 
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I understand that. But on hydraulic especially; Crower and Howards Cams both say just take it to zero lash and tighten down the poly lock. On hydraulic, you want the plunger to bleed all the way out. Which gives more accurate valve events with high rpms.