I might have torqued my heads wrong but is it really going to matter?

[evil666]

I finished torqing the stock iron heads on the car but, I might have done a mistake but I don't really know if it is going to matter much. The head bolts that I am using are the ARP and this is the way I torqued them using the stock GM head gaskets. I started torqing at 55 lbs and went up by increments of 5 lbs a shot and ended off with 83lbs to end off, for EX: 55-60-65-70-75-80-83. Today I rememberd that once I read that I should have torqued the heads at 25 lbs to start off then go to 50 and so on. What I would like to know is if the way I did it is really bad or it won't really matter?

Thanks for any info to my question.
Marco.

86 Grand National t-top (59900km)
stock long block,stock suspension, red stripe convertor, te44, smc alk injection, 24lbs boost, 94 octane, hooker cat back with dyno max ultra flow muffers, tomco 30lbs injectors, dynotech stage 4 street chip, thdp, mease 24 row IC, Ron Custom max boost brake module, MT drag radials (275/50/15) 3800lbs race weight with driver. (Torque convertor not locked)
BEST E/T
60FT=1.52
1/8= 7.38
I/4= 11.74
MPH=113
BEST MPH= 114

 

[Jerryl]

..... I started torqing at 55 lbs and went up by increments of 5 lbs a shot and ended off with 83lbs to end off, for EX: 55-60-65-70-75-80-83. Today I rememberd that once I read that I should have torqued the heads at 25 lbs to start off then go to 50 and so on. What I would like to know is if the way I did it is really bad or it won't really matter?

I am certainly no HG expert (and don't want to become one ) but would think it should be ok. Everything else followed to a "T"?

 

[Squid4life]

I think most say to go 25 to 50 then to final because they do not want you to go straight to final spec the first swing because you may end up deforming the gasket or pinching it. I would think 25-50-spec is their idea of "minimum increments" and you just went one step higher starting out with. I would say you are fine. I have seen plenty of NA motors go straight to spec, no steps and they were fine. (and I know someone will comment NA is not turbo'ed )

 

[buickboy]

All I can say is you have a very patient wife or girlfriend. Most would be sticking their head out the garage door and saying "are you done yet"? You should be just fine with the HG's. That must of taken a while.

Mitch

 

[Squid4life]

maybe that is why he did it in such small increments, to stay in the garage LONGER than really necessary. Good idea!

 

[VadersV6]

The exact sequence isnt always as important as people believe. As long as you start with the centermost bolt, and spiral your way outward, it's good to go. As far as the force increment goes, the smaller, the better. This is because of bolt stretch. You can torque to 25, wait a couple hours, go back, and the torque will be at 20. Not only did the bolt stretch, but the bolt rotated a bit counterclockwise...this is cause when you torqued it, the bolt not only stretched, but twisted. You wait awhile, and the bolt will untwist, and stretch. we used to torque the rod caps on all our race engines by measuring stud stretch. Torque numbers were not important. I would always recommend using new head bolts every time the heads come off, because on some engines, the manufacturer uses stretch to yield bolts. Its like a coat hanger that was bent just far enough to permanently deform. Once that has happened, that deformed spot has lost most of its strength and it cant be bent back or be restored. You torque the heads down, and before you know it, you've lost a head gasket because the permanently damaged head bolts you decided to re-use, stretched ALOT and you lost all your torque. They stretch alot because the metal had been altered permanently the first time they were torqued. Unless you're using top notch hardware, toss the head bolts in the trash and buy new, high quality head bolts or better yet, studs.

 

[evil666]

The exact sequence isnt always as important as people believe. As long as you start with the centermost bolt, and spiral your way outward, it's good to go. As far as the force increment goes, the smaller, the better. This is because of bolt stretch. You can torque to 25, wait a couple hours, go back, and the torque will be at 20. Not only did the bolt stretch, but the bolt rotated a bit counterclockwise...this is cause when you torqued it, the bolt not only stretched, but twisted. You wait awhile, and the bolt will untwist, and stretch. we used to torque the rod caps on all our race engines by measuring stud stretch. Torque numbers were not important. I would always recommend using new head bolts every time the heads come off, because on some engines, the manufacturer uses stretch to yield bolts. Its like a coat hanger that was bent just far enough to permanently deform. Once that has happened, that deformed spot has lost most of its strength and it cant be bent back or be restored. You torque the heads down, and before you know it, you've lost a head gasket because the permanently damaged head bolts you decided to re-use, stretched ALOT and you lost all your torque. They stretch alot because the metal had been altered permanently the first time they were torqued. Unless you're using top notch hardware, toss the head bolts in the trash and buy new, high quality head bolts or better yet, studs.

Vader I am not sure if I understood you right but if I did this is what I understood, if I was using new head bolts there should be no problem with the way I torqued my heads and if this is the case I did use new ARP head bolts.

Thank you everyone for giving me your opions.
Marco

86 Grand National t-top (59900km)
stock long block,stock suspension, red stripe convertor, te44, smc alk injection, 24lbs boost, 94 octane, hooker cat back with dyno max ultra flow muffers, tomco 30lbs injectors, dynotech stage 4 street chip, thdp, mease 24 row IC, Ron Custom max boost brake module, MT drag radials (275/50/15) 3800lbs race weight with driver. (Torque convertor not locked)
BEST E/T
60FT=1.52
1/8= 7.38
I/4= 11.74
MPH=113
BEST MPH= 114

 

[750H.P.V6]

Not exactly.

What you're doing by applying a torque to the bolt is attempting to achieve the correct stretch on the fastner. Torque is an approximation at best and will depend on the friction between the bolt threads and the hole, as well as the underside of the bolt head and the washer and will be different depending on the friction coefficient of the lube/sealer you use. If you torque your heads to their full spec (lets say 80ft lbs) and mark the bolt heads then come back later the torque might be less than originally but the bolts don't back off. The gasket usually compresses. Too small of torque increments can work against you because a 5psi difference may not be able to overcome the friction between the fastner threads etc. to make the bolt rotate. As stated don't re-use torque to yield fastners.

Neal

The exact sequence isnt always as important as people believe. As long as you start with the centermost bolt, and spiral your way outward, it's good to go. As far as the force increment goes, the smaller, the better. This is because of bolt stretch. You can torque to 25, wait a couple hours, go back, and the torque will be at 20. Not only did the bolt stretch, but the bolt rotated a bit counterclockwise...this is cause when you torqued it, the bolt not only stretched, but twisted. You wait awhile, and the bolt will untwist, and stretch. we used to torque the rod caps on all our race engines by measuring stud stretch. Torque numbers were not important. I would always recommend using new head bolts every time the heads come off, because on some engines, the manufacturer uses stretch to yield bolts. Unless you're using top notch hardware, toss the head bolts in the trash and buy new, high quality head bolts or better yet, studs.

 

[750H.P.V6]

Guy's,

I re-read what I had written above and where I wrote 5psi I should have written 5 ft lbs. I must have boost on the brain.

Sorry for any confusion

Neal

 

[VadersV6]

Yeah I guess all those years of actually seeing it happen on thousands of race motors I machined and built was just a big illusion while trapped in the matrix. Damn Agent Smith lied to me me again.
All things being the same....oil under the head of the bolt, threads being clean, gasket being compressed.....this phenomenon does happen. So take your time with the torquing sequence.

 

[750H.P.V6]

Sounds like.

Neal

Yeah I guess all those years of actually seeing it happen on thousands of race motors I machined and built was just a big illusion while trapped in the matrix.

 

[Lee Thompson]

yes

I'm on your team Neal.