Hey guys

I have a set of Supertech 75's installed. Installed the cams into the head and the cams won't turn a full rotation.

Springs dont appear to be binding. They cant really be installed wrong. All the keepers went in fine.

Had the lash adjusters out and in oil. Could they be over expanded?

 

well theres nothing eles to stop the cams from turning.
R u using stock cams??

 

ZZP stage 2.

We put them in a head with stock springs and they worked fine.

 

The supertechs will be way stiffer and make it harder to turn the cams. U try aplying more force to turn them?

 

Yup. Snapped 4 of the rockers on one side.

 

theres something else going on here.... take the cams out and inspect the springs. also check the spring to head clearences. the springs sometimes hit the casting

 

all the springs dont make any contact with the head. The outter springs are not being compressed all the way. It is hard to see but I dont believe the inner springs are also being collapsed. The seat for the inner spring was installed.

 

was the head on the engine

 

Head with the supertech springs is on the engine. The cylinder the the lobes were pushing down, we made sure the piston was at the bottom.

The head with the factory springs was on the bench

 

no matter what cylinder you have at the bottom you will always have 2 at the top so I would say the reason why it wont turn over is the valves hitting the pistons if you want to rotate the cams then put the pistons(all 4) in the middle of the stroke

 

i have to agree with mr b if everything iI said checks out. If you broke rocker rollers you will be lucky to have not of bent valves

 

cams do not have gears or chain installed, we we are only moving one cam at a time. This way we are only opening one set of valves.

 

that doessent matter because if any of the pistons where still too high then you can still contact them.

I mean if a motor stops you should never force it just back it off and asses what it going on before you do damage

 

and if a piston is at tdc you will smack the piston with a valve these are interference engines

bingo was his name o

 

Yup... Your cams are 120* out, to get them in phase, you will need to go BDC or half stroke depend on with 1/3 rotation you are stuck in

 

oh god bless your soul dwarrick

 

How would the valves hit?

Regardless head is off the car. No marks on pistons. No bent valves. Re assembles and tested on bench. Cams still not turning.

 

The cam will make it about 75% to the tip of the cam before it jams.

Happens both on bench and on veh.

We tired with all the pistons in the middle of their stoke so it would be impossible for the valves to hit anyways.

Only thing I can think of is the Year of the head is unknown since bought used off mongo. I don't think any changes to the head happened though the LSJ years thou

 

sounds like theirs a fitment issue with the springs.... did a machinest do all of the work and a valve job?

 

the only other couple of things that would keep the cams from rotating is coil bind or the retainer hitting the valve guide

I ran the zzpstg2 cams with no problem of binding or hitting

 

It has to be something with the springs. They were installed when they head got a valve job, port and polish.

Think I'm gonna swap then for a set of ZZP or werks ones

 

werks ones are made here locally. I can set you up with um when your ready if that's the route you want to go.

 

Found out the problem.

After a few weeks of just not caring I went back to the car to find the problem. I know it is something in the valves/springs as I tired everything else.

Took the springs off to check for problems. The seats for the inner seats were installed upside down. I guess it would cause the inner springs to compress flat and stop the cam.

Removed them all and installed the right way and cams turn as they should.

Just as I get all excited to finally get things back together, my brand new timing chain has a twisted link. FML

 

Good deal