Ticking Valve Train

[88gt40]

Need some help, I have had issues with my valve train. It's been ticking, so I pulled the valve covers and found the pushrods were to short. I used a pushrod length checker and found that the ones in it were 6.243", the checker had me at 6.252. I ordered 6.272, I installed them and they still tick. I installed new 1.6 roller rockers also, it did quiet down some but not completely. I read that u are suppose to add .20-.40 for preload, but I measured them when the lifter was all the way down. After putting the rocker in and new pr I torque them to 20ftlbs. So now nothing is loose now and the pushrods are all still at zero lash even after I ran the hell out of it. So where is the ticking coming from, checked for exhaust leaks and found none. So any advice would help, it has to be simple. One thing is I did not build this engine I bought the car like it is. 306 gt40 heads intake and comp cam 270. 24lb injectors, and bbk cold air intake. Is it possible that it has timing gears? Would they make this racket, is there anyway to find out without tearing down the front?

 

[88LX5.Oh]

Gear driven timing set will make a whine like a supercharger, not a ticking

 

[Grabbin' Asphalt]

Any chance bad/old lifters causing them to not pump up??

 

[88gt40]

That's what I was thinking, I may go that direction next. I need to pull the intake anyway, have a stripped hole to repair. While I'm in there I will change the lifters

 

[Strype]

Call me if you need some help. I'm working on my window.

 

[Maryland Stang]

Need some help, but I measured them when the lifter was all the way down.

Yes, you do need help. Are you saying the lifter was compressed or that the lifter was on the base circle of the cam?

 

[Strype]

Here is the car just for reference:
http://www.stangnet.com/mustang-forums/threads/wierd-5-0.869155/#post-8736651

I remember guys from long ago telling me that GT40 heads will work with stock 5.0 pushrods, but they aren't exactly the correct length and they'll tick. I think this is exactly that problem.

 

[88gt40]

I rotated the engine all the way to the flat spot on the cam.

 

[mikestang63]

not to sound like an azz, but are you using a hydraulic lifter when measuring for the pushrod? That will always give an incorrect reading. You need to either use a solid lifter or convert over a hydraulic one. It is also very important to check both the intake and exhaust valve. Here is a good reference point for you

http://forums.corral.net/forums/5-0...ng-around-about-measuring-pushrod-length.html

 

[Gearbanger 101]

Try using this as a guide...

http://www.fordracingparts.com/download/instructionsheets/FordInstShtRocker_Arm_11_30_10.pdf

I don't recall you saying what brand/kind of rocker arms you were using?

 

[88gt40]

I'm using scorpion 1.6 roller rockers pedestal mount.