I have been having trouble with the valve train on my L05 350 TBI. I blew a head gasket on it and while the heads were off I had 2.02" intake and 1.6" stainless valves with high performance 110# double valve springs and 1.6 ratio roller tip rockers. Also had heads machined for guide plates and .045 taken off the head for increased compression. I then put ARP screw in studs in the beast. I had been running a Compucam 2050 in the thing for the last 5 years with the following specs. 216* intake /228* exhaust @.050 also .454/.480 lift with the original 1.5 ratio rockers and 112 degrees lobe separation.

Now for the problem. Ongoing for about 1k miles it has bent a few pushrods. I have had different people look at it. Used different brand hardened pushrods and nothing helped. Now it has worn off one lobe of my cam completely and one of the others is bending pushrods instantly. I have another lifter that is refusing to pump oil even though I have great oil pressure. I can't seem to get any of the valves adjusted correctly now. What is it? The engine ran great for the first 200-300 miles.

I have a set of roller lifters, pushrods and cradle from an Iroc (my block has the setup to run the roller cam) and I recently purchased an LT1 cam from ebay which from Vaders specs he posted the other day has slightly less duration and more lift than my now dead compucam.

Is my problem that the valve springs are binding (which is what I am leaning towards) or is my valves lightly hitting the piston. I really don't want to pull these freaking heads again. I am just trying to get this engine to run through the winter.

What valve springs do you recommend to go with the LT1 cam with 1.6 ratio roller tip rockers? Note: I do not want to remove the head to machine for larger springs. Is there a way that I can check my springs for binding while the old stuff is still in there.

It is just this kind of crap that makes me recommend to most inexperienced people to buy crate motors instead of building there own. I have rebuilt 4 car motors and several motorcycles but when it comes to changing from factory specs my stuff starts turning to **** the deeper I go.

 

Did you have the valve guides milled down? It sounds to me like the retainers are running into the top of them at full lift. Very common on later model heads. The Vortec heads do this at around .480 of lift; you have a good bit more than that. Pop a valve spring off of a valve with a bent pushrod and look closely at the bottom of the retainer and the top of the valve guide; I'll bet you'll see the imprint left by the problem.

Don't worry about the whole "crate" motor thing; even if somebody else (even in some other city!) had taken those same parts and assembled them, the act of bolting it to a crate still wouldn't have fixed it.

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"So many Mustangs, so little time..."
ICON Motorsports

 

My retainers don't lip out over the valve spring like the stock retainers did. I changed them to a flat top style retainer.

 

Thshpe of the top of the retainer has nothing to do with the issue at hand...

Take a valve spring off, and look at the underside of the retainer in the center. See if it has been hitting the top of the valve guide. The retainer has the part that sticks downward into the center of the spring, and the valve guide sticks upward into the center of the spring. The clearance between the top of the valve guide and the bottom of the retainer is what you need to find out about.

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"So many Mustangs, so little time..."
ICON Motorsports

 

Thanks will do.