Re-Tourque heads
- Thread starter Hu Ryde
- Start date
myclone
Donating Member
Depends on what head gaskets youre using. If they say no retorque needed then I wouldnt bother. If they dont say anything about retorque Id retorque em after one heat cycle.
How to torque head bolts is another lengthy subject that prolly has as many opinions as there are ppl to ask.
How to torque head bolts is another lengthy subject that prolly has as many opinions as there are ppl to ask.
V6 Kompressor
New member
Opinion... why yes.... It is ALOT of work to get to the head bolts in order to retorque them, but it can't hurt... I would set the torque wrench to the max recommended setting and go over all the bolts in the proper sequence once. If you use fel-pro's you're not supposed to have to retourque them.... If anything, you need to re-tourque the lower intake manifold, occasionally, because it is aluminum and they are usually bolted to a set of Iron heads (Different expansion rates). If you ever run the engine hot, I would check them then, for sure...
I've done head swaps and motor builds on a dozen small-block Chevys, using only Fel-Pros and GM head gaskets. They are composition head gaskets that do not need to be re-torqued. I've never retorqued any heads and I've never had a blown head gasket.
Might be different for a high-psi Sy motor, but I doubt it. You've got 5 bolts around each cylinder clamping the head down. It is pretty reliable.
Might be different for a high-psi Sy motor, but I doubt it. You've got 5 bolts around each cylinder clamping the head down. It is pretty reliable.
Jesse, on the advice of ARP, using their head bolts, I torqued my aluminum LT1 heads to 90 pounds. I thought, "What the hell, I plan on using nitrous." Used N20 for only 4 races, but everything is fine 3 years later. Though I now believe that 90 ft/lbs is unnecessary. 65(stock) or even 75(with good bolts) is plenty.
nightdiver
Active member
Head gaskets has nothing to do with the amount of torque
The numbers we are given comes from the bolt strength it self
Here is the story:
In 1988 i went to Germany and staied by one of the biggest gasket factories
ELRING DICHTUNGSWERKE
After 3 months in the research department one of the things i learned is the bolt story...here it is
They take a new bolt and torque it in a tester/reader machine
This way they can see how much power they put and how much they receive untill the bolt brakes
There is the elastic and the plastic area on the diagramm
After years of tests they found that the point that we must torque the bolts is inside the first plastic area.
The elastic area is when we torque a bolt and then remoove it back and it has the same lengh
The plastic area is when the streching beggins
When someone torques the bolts more than specified it looses the elasticity and the bolt doesnt have the strengh to hold the head down
When someone torques more a head down with stronger bolts the liner or bore will not be in a good shape any more
This is the way they decide how much they will torque a head
We tested several engines on the stands ,specialy for big trucks, and i know the Germans do the perfect job everywhere
I hope i helped a little.
The numbers we are given comes from the bolt strength it self
Here is the story:
In 1988 i went to Germany and staied by one of the biggest gasket factories
ELRING DICHTUNGSWERKE
After 3 months in the research department one of the things i learned is the bolt story...here it is
They take a new bolt and torque it in a tester/reader machine
This way they can see how much power they put and how much they receive untill the bolt brakes
There is the elastic and the plastic area on the diagramm
After years of tests they found that the point that we must torque the bolts is inside the first plastic area.
The elastic area is when we torque a bolt and then remoove it back and it has the same lengh
The plastic area is when the streching beggins
When someone torques the bolts more than specified it looses the elasticity and the bolt doesnt have the strengh to hold the head down
When someone torques more a head down with stronger bolts the liner or bore will not be in a good shape any more
This is the way they decide how much they will torque a head
We tested several engines on the stands ,specialy for big trucks, and i know the Germans do the perfect job everywhere
I hope i helped a little.