Got a good one...AL heads + roller rockers = runs like crap.

[Mustang5L5]

Yeah that's exactly the case. 10+ hours with no food or drink gets to you and i think that's how we missed it.

Gonna pull the valve covers and start over with the rockers.

What's a good method to insure that the lifters are fully pumped up before we start this? WOuld a couple cranks before pulling the vc's work or would the tension from the springs (if a valve is open) cause it to bleed down in the 10-15 mins it takes us to get down to them??

 

[bluevenom867]

Yeah that's exactly the case. 10+ hours with no food or drink gets to you and i think that's how we missed it.

Gonna pull the valve covers and start over with the rockers.

What's a good method to insure that the lifters are fully pumped up before we start this? WOuld a couple cranks before pulling the vc's work or would the tension from the springs (if a valve is open) cause it to bleed down in the 10-15 mins it takes us to get down to them??

Pull the coil wire off the ignition and loosen the locks.Then crank it and do what I posted above.

 

[Mustang5L5]

Got it...thanks

 

[5spd GT]

I know you quite possibly figured out your problem...but just to clarify things...you want to tighten when the valve is completely closed...

Even with my cam, when I follow the "stud mounted" adjustment procedure a valve (like you were seeing) is still slightly open. Just sometimes you have to spin it just a bit further than the instructions if that makes sense. I keep a hand on the rocker I'm going to adjust and push down on it to make sure the lifter didn't catch in it's bore and keep the rocker/rod/lifter up and make you think it is on the base circle.

Simply put, make sure it is on the base circle. It needs to be on a "no rise" point when you go to tighten them.

Also tighten them 1/2 once you spin the pushrod and feel tension. I think a full turn is just a bit much, especially for high rpm's...

Yep, just because they are stud mounted rockers does not mean you need hardened pushrods. That is due to the guideplates...and the rubbing that takes place...

good luck! Seems like you got it...

 

[Mustang5L5]

Sucess!!

Turns out the rockers were adjusted fine.

It was an incorrect lower intake gasket that allowed a 1/16" gap which created a HUGE vacuum leak. We found it spraying carb cleaner around the engine.

Luckily local speed shop had correct gaskets. We also measured and ordered the correct pushrods for our application.

Engine sounds strong, runs great and car is much faster than before. Thanks everyone