Wierd popping noise...

[WayFast84]

But from reading about coil bind its basically to much lift for the springs right? If it is coil bind should I replace the springs or should I change the rockers if I can get away with it.

Originally Posted by LTs1ow

Dude, all you have to do is pull the 12 or whatever bolts to pull off the intake. The rocker is already off anyway so thats easy enough, borrow a SR lifter from that friend of yours and check it out. Simple, and much cheaper than having the whole valvetrain fail on you.

been there done that. At this point I would rather pay some one to fix this car so I don't have to keep chasing after it.

These heads where just machined and put back on by a shop that new the problem, You would think they would have checked all this stuff.

[LTb1ow]

Fixed, dunno why I said SR.

[WildBillyT]

Originally Posted by WayFast84

But from reading about coil bind its basically to much lift for the springs right? If it is coil bind should I replace the springs or should I change the rockers if I can get away with it.



been there done that. At this point I would rather pay some one to fix this car so I don't have to keep chasing after it.

These heads where just machined and put back on by a shop that new the problem, You would think they would have checked all this stuff.

What do you mean by "machined"? What exactly was done?

[WayFast84]

I believe they where decked. They wanted to make sure the cylinder heads were true before they put them back on.

I came to the conclusion that as soon as the shop finds out whats wrong with it I'm going to be changing to 7/16 rocker arms and 1.5 rockers to go along with it..

[WildBillyT]

Originally Posted by WayFast84

I believe they where decked. They wanted to make sure the cylinder heads were true before they put them back on.

I came to the conclusion that as soon as the shop finds out whats wrong with it I'm going to be changing to 7/16 rocker arms and 1.5 rockers to go along with it..

Was that all? Do you remember the jegs part number for the heads?

[WayFast84]

809-12558060

Thanks for taking all this time to help me out. I appreciate it.

[WildBillyT]

WF:

That's GM PN 12558060, as below.

http://www.sdparts.com/product/12558...Assembled.aspx

I am not trying to get you to chase a unicorn but I am trying to figure out if your heads were modified enough to handle a higher lift cam. In my uneducated opinion it looks like you are running too much lift for stock Vortecs with a spring change, and it sounds like that's what you have. Post a close up pic of the top of your cylinder heads/valve springs if you can.

[bubba428]

hmmmmm what piston are you running in that? did you check the V-P clearance??? I can't quite grasp why this is happening. I'm running a .525/.546 lift cam on a set of #416 heads off a 305 I found in the junk yard that has 2.02/1.60 put in and .550 lift clearance. I've revved this to 6k without a peep from the valvetrain. did you replace your rocker nuts or give 'em the ol' sledge whack? I noticed that with the intake I put on my build that on one side the intake bolt goes too far into the head and actually hits the push rod, it mangled the hell outta my push rod. maybe you have a similar compatibility issue????

[WayFast84]

I think thats what it is bill. I beleive I told the machinist to use the springs that wouldnt require modifications to run higher lift and he used a different set of springs. Now in order for these to be modified to run more lift will the heads have to be taken off?

[bubba428]

not necessarily... if your real careful about it you can get a set of springs rated for higher lift with the same diameter ans stock and just swap the springs. but DON'T drop the valve

[WildBillyT]

Originally Posted by WayFast84

I think thats what it is bill. I beleive I told the machinist to use the springs that wouldnt require modifications to run higher lift and he used a different set of springs. Now in order for these to be modified to run more lift will the heads have to be taken off?

WF:

You need to talk to your machinist. Really. Anything on here is speculation. Maybe he did use a set of springs that allow you to run the cam you want. I don't know what you have. I know you know of the NastyZ post since you quoted it. I also know it's a huge thread that's tough to read through in its entirity. But at least get very familiar with the first 3-5 pages of it.

Anyway, If you DO need to do the modification the heads need to come off.

Read this, but remember it may be a few years old and there may be new parts out that make it easier:

http://www.chevyhiperformance.com/ho...458/index.html

[WayFast84]

If this is the reason I would rather have the camshaft replaced with something smaller and much more mild. If I measure for coil bind I can tell the exact lift my set up can take?