The HG thang

[Supracentral]

You should do what makes you comfortable. I understand my view on this will be controversial but that how I feel. As long as the fasteners are installed correctly there should be no need for it and my experience has borne that out. Does ARP even say do it? Last time I checked they said to incrementally torque on installation which is what I've always done.

Never done a retorque on 30+ motors I've built, never had a problem. I think the issue with some is most of the time when the head studs or bolts loosen up over time after the re torque is due to the aluminum being annealed from previous over heat. Often over looked when putting back together.

This is pretty much my experience. We never ever did retorques on 1,500+ RWHP drag motors.

If you chase the threads, use the proper lube and torque in increments as described you won't have problems. Do it right the 1st time and you won't have to worry about it.

 

[CyFi6]

It has to do with the head gasket type/material, and the manufacturer will tell you if a retorque is required. The 7m Felpro gasket is a "permatorque" type and does not require a retorque, but its easy enough that I do it on my car.

 

[stevenr816]

I've never retorqued either. With felpros or mhg. All my motors are still running to this day as well as 35psi on my dsm.


Sent from my iPhone using Tapatalk

 

[3p141592654]

Re-torque seems to be one of those "religious" things. I never do it, and when I have bought a new car the manufacture has never told me to bring it back later so they can re-torque it. That said, do what you like, I doubt it can hurt anything either. Cleanliness probably plays a role in any scenario where bolt tension is claimed to have shifted.

 

[CyFi6]

Just a few examples I found where a retorque is required.

Ford retorque procedure
http://www.fordscorpio.co.uk/manual/engines/tdi/TDICHBolts.pdf
"Retorque cylinder head bolts
Before carrying out the following operation,
allow the engine to warm up for about 20
minutes and then allow the cylinder heads
to cool down to about 40°C."

Edleborck instructions
http://static.speedwaymotors.com/pdf/325-1115.pdf
"A re-torque is necessary after engine warm-up and complete cool-down. A re-torque
after each of three (3) hot-cold cycles is recommended for normally aspirated engines, and a re-torque after each of five (5) hot-cold cycles
is recommended for forced induction (blown) applications."

GM instructions
http://www.chevroletperformance.com/_res/pdf/installation_guides/small_blocks/zz383/ZZ383_Engine.pdf
"Cylinder head bolt (sequenced). Re-torque bolt after running engine for 10 hours."

Some kind of outboard motor
http://www.marinemechanic.com/merc/headtorque-135-220-EN_15.pdf
"It is necessary to retorque the cylinder head bolts on
the previous style blocks after the outboard has been
run the first time.
Warm the block completely by running the outboard
1/2 to 1 hour. Allow the block to cool for 2 hours. Retorque
the cylinder head bolts when the engine is
cold. Follow the torque sequence and do one bolt at
a time. Loosen the bolt 1/4 turn and retorque it to 30
Ft. Lbs. (40.7 N·m)."

Trickflow heads
http://static.trickflow.com/global/images/instructions/tfs-dp-18.pdf
"A cold re-torque after the initial break in period is
required to maintain head gasket integrity and combustion
seal."

Ford Racing instructions
http://www.jegs.com/InstallationInstructions/300/397/397-M-6049-C460.pdf
"A cold re-torque after the first running at temperature is
mandatory to maintain head gasket integrity and combustion seal."

Just to show that retorques are absolutely necessary/mandatory on some head gasket designs.

 

[jetjock]

And yet nowhere will you find it required on aircraft engines where the crankcase is even held together by the cylinders. Then again there's no gasket involved. You're right about one thing though: it's not about the fasteners.

 

[f00g00]

And there I go getting suckered into buying used arp bolts.
Sunavabitch.

Damn, that means you didn't get the cool ARP sticker.
Before I went 1J I went through several 7MGE's all because of HG problems. The last one I put in lasted over 2 years after re-torquing to 72 foot pounds then it got thrown out after the 1J swap.

 

[o1supra]

I replaced my BHG with a felpro gasket from autozone and reused my factory head bolts torqued them down to 80 according to the needle dial that was over a year ago never had a problem with it. Now I use it as a daily driver but i dont abuse it i just drive it and enjoy it. So if your just going to drive it it'll be fine if your going to race it boost it or something like that you might have a different outcome but as for me mine is still rolling with no problems. knock knock [thats me knocking on wood] LOL good luck!!!!!!!