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Need help. No compression.

Old Jul 17, 2005 | 06:53 PM
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Default Need help. No compression.

This weekend I put a set of AFR 205s on the car, as well as morel hydralic lifters. Got everything back together today, go to fire it up, no compression. Pull the valve covers, the springs are compressed. I'm like, wtf. I was thinking somehow the pushrod might be too long, so I tossed in a set of 7.35s, still no compression. If i turn the motor over with the rocker arms loose (not torqued) there is compression.

I was under the impression I could run stock rockers with the morels, was I wrong?

The parts involved are as follows:

AFR 205s as cast w/ the valvesprings AFR sends out assembled.

7.35 hardened pushrods

stock rockers

Morel hyd roller lifters

220/220 581/581 110lsa lunati grind

Those are the only components that could be involved in the problem, I believe

Any ideas on what I have going wrong?
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Old Jul 17, 2005 | 07:33 PM
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Anyone know what rockers will work with the morels? Obviously I either need shorter pushrods or shimmed rockers etc.
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Old Jul 17, 2005 | 07:47 PM
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How much taller are the Morel lifters as compared to stock? If they are "slightly" larger, I would think they would eventually bleed down to acheive zero lash. I think the only thing you can do now is get an adjustable pushrod, find correct valvetrain geometry (do a search, there are very detailed instructions posted elsewhere) then measure the pushrod and order accordingly.
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Old Jul 17, 2005 | 07:48 PM
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I just did a quick check and there is no mention of a height difference on the morel lifters. Are you sure you put the pivot support plates under the rockers, I remember stories of folks leaving those out and winding up with a problem like yours.
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Old Jul 17, 2005 | 09:29 PM
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It's your cam! It's too small!
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Old Jul 17, 2005 | 10:53 PM
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I was pretty sure I could use close to stock pushrod length, especially since my heads aren't milled and I'm using MLS gaskets, but apparently things aren't working out. I'm just wondering if I should solve the problem by using a shorter pushrod or by raising the rocker with an adjustable setup and shims.
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Old Jul 18, 2005 | 07:48 AM
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If everything is still stock dimensions, then you shouldn't need custom stuff.
Somebody made a good point about the plate that goes under all the rockers. Still there?

How long did you let the engine sit after tightening the rockers? Maybe they just need time to bleed down some? When you install adjustable rockers, they tell you to wait 30 minutes after each 1/4 turn.

With the lobe on the base of the circle, just how much does it compress the spring when you tighten it down?
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Old Jul 18, 2005 | 08:58 AM
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The plate is there. I torqued everything down to 22ft/lbs and let it sit for a few hours.
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Old Jul 20, 2005 | 07:11 PM
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Morels are indeed taller than stock lifters. I used an adjustable pushrod and will be using 7.300 pushrods.
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Old Jul 20, 2005 | 08:04 PM
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Sweet! Hope it works out for you!
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