Wanted to post this in the drag forum since I really am looking for some opinions from serious racers here and not just the average 250whp stock motor with head studs.

Was talking to a guy who runs an X275 drag radial car making huge power (OHC Ford mod motor now with an f1x on it)... he suggested I try a method beyond my normal just hand tight studs into block and 3 step torque down in sequence to a final value, done.

He suggested burnishing if new studs. Snug them in the block 10# or so of torque. Go through in sequence torquing them in 3 steps just like normal. Once all are at final value though, he said 1 by 1 go through (in sequence) and loosen up each head stud till no torque on them then in a smooth continuous even pull, pull it back to your final value. Doing this for each in sequence. Then just go over them to ensure they are at final value. Done. (This would be with 12mm ARP's with ultra torque moly to 90ft lbs final)

Anyone use a method like this? Hopefully it is not a silly question, just happened to have the head off for another reason and was suggested I try this method when putting it back together. Seems everyone has a little different method but never seen it talked about much on here.

 

Factory specs are two steps.

 

Its not a factory spec motor or factory tty bolt anymore. ARP recommends a 3 step process as standard for their head studs and I am curious about a variation to it like I described in my OP.

 

I use a process very similar to that. I was only making 420hp last year, but i know of others that do it that way also.

 

I use L19 studs...35,70,105...in a smooth non stop motion on each sequence. If I keep lifting I will switch to H11's.

 

Golden eagle head studs use about the same process.

 

With the use of metal headgaskets I like to use a process of going to the first stage torque, loosen all, first stage torque, loosen all, first stage torque, 2nd stage, and final torque. This allows you to crush the headgasket fully and get a more accurate final torque value. Ive yet to ever run into a problem.

I was using GE b16 headstuds on my SR20 motor and 36 lbs of boost, 650whp and never lifted the head. Cosworth headgasket btw.

I use this process on all head studs and with the use of metal gaskets, obviously using the torques recommended for the each different brand stud. Havent had any issues.

On my current build im on a sleeved and stepped deck block with Mazworx 1/2" headstuds and OEM VET metal headgasket. Ill be doing the same process just using the given values by Mazworx.

 

Thanks for the replys so far, appreciate it. I know it is a kind of basic question for this forum but I want to make sure I am using the best method to get accurate torque on the studs.

Hrm good info to know. Just looked their installation process .pdf, it does very similar to this it seems but instead of doing it on the last step they are doing it on the 2nd.

 

Torque the nuts down in four equal steps 20 40 60 80 and then heat cycle the engine getting the thermostat to open, let it cool down overnight then re torque if needed, job jobbed.

 

spoolie where did u get your l19s at and what are h11?

 

i go 2 steps.
20lb then straight to tq specs

 

blueprint racing was making L19 b series studs i believe

 

This may be how you do it, but in reality it's best to do hot-torques for the final check. You'd be surprised at the difference between the two. Check with the stud MFG and see what they recommend. I use AEBS and do hot-torques. No problems yet and I'm on a Benson sleeved block w/ no orings.

 

............and you fellows are correct, except running E85 fuel is higher pressures and head lift is a big problem when in higher boost levels. That's why I run better studs.

 

Can anyone else back up this statement? I didn't know this....

 

Also curious what others think about that.

For reference this is on a f22 SOHC that was previously made 613whp/ 514wtrq on leaded 112 (6265 billet) tuned by Tony1... some changes have been made to accomidate switching to e98, getting retuned (again by Tony) in the not so distant future.

 

I call bs... where did you come up with this.

 

Damn right, cylinder pressure is cylinder pressure regardless of what fuel you make it with.

 

Not an F, But 89mm GE step decked H
Follow ARPs insructions, but on final I go 5 over, then go through rotation backwards twice more @ final TQ.


At around 200 miles or so I go through them again..


Has worked for me so far.

 

Looks like I may just stick with what I know, not real comfortable with the new process. Tried it after the first step @ 30 ft lbs, loosened it back up, and then back to 30 ft lbs... but when loosening all it did was back out the stud from the block itself and make me snug it back into the block/ start again.