Arp head bolt install

[Brigsy]

Evening all.

Quick one regarding arp head stud install on the F4R. Ive read the arp instructions and it says lube up with arp lube, wind hand tight into the block, and torque down to 105ft/lb in 3 stages compared to the usual angle tighten that is specced with stock bolts.

Is it as simple as that? Reason i ask, is when i removed the head from the previous engine, the nuts were not mega tight. Well did not seem to be 105ft/lb tight, and i seen a head that had cracked around the head bolts ages ago, so dont want to be that person who f***s it up as got a few quid in the head.

Any advice appreciated.

Cheers.

 

[NorthloopCup]

I fitted some of these on @Tom Johnson ‘s engine build, and I’m pretty sure I followed the arp instructions mate.

 

[Brigsy]

Spot on, cheers mate. Its my first go with arp head studs. I was not expecting the old way of torquing down, reminds me of doing the r5gtt head bolts so thought it was best to confirm.

Next question, 11mm socket, or imperial? They both seem to fit OK. I take it that imperial is right, with them being american.

 

[JamesBryan]

11mm or 7/16ths are pretty close, but I'd use imperial if you have it.

Would probably do 35-75-105.

Once it's been left for a bit at full torque, you could check again at 105, since the headgasket will have compressed a tiny bit.

 

[Brigsy]

Good shout. I was thinking about doing first 35 then let it settle for a few mins, check torque is still 35 then go last 2 stages.

Its a pain on these once cam cover is on cant get to head bolts. On the older stuff ive always checked torque after run in.

 

[JamesBryan]

Good shout. I was thinking about doing first 35 then let it settle for a few mins, check torque is still 35 then go last 2 stages.

Its a pain on these once cam cover is on cant get to head bolts. On the older stuff ive always checked torque after run in.

Yeah could do that as well at the first stage tbh.

Being able to re-torqe after run in would be ideal wouldn't it 😅

 

[Robbie Corbett]

I haven't fitted them for years but on the last engine I used them in the recommendation from an engine builder was to retorque after a few heat cycles and they did indeed take a little extra - not much.

ARP state that you should not need to do a retorque but advise that with some gaskets you might have to and that the retorque should be done with the engine cold.

 

[Donny_Dog]

Seems a high torque value. Not that I know otherwise.
Saxo was 60. Which seemed on the low side, but confirmed with pug1off. Strange.

 

[JamesBryan]

Seems a high torque value. Not that I know otherwise.
Saxo was 60. Which seemed on the low side, but confirmed with pug1off. Strange.

Roughly 140nm, not that bad.

 

[Donny_Dog]

Roughly 140nm, not that bad.

Say what... 60ft/lb is around 80nm no?
Theyre holding my head down, but less torque than a wheel nut.

 

[Robbie Corbett]

Say what... 60ft/lb is around 80nm no?
Theyre holding my head down, but less torque than a wheel nut.

He means Brigsys setting. 105 ft.lb comes out at 140ish Nm.

 

[Brigsy]

I guess 105ft/lb isnt a million miles over the oem stretch to yeild bolt torque when they are angle tightened.

 

[JamesBryan]

Yeah sorry, meant the 105ftlbs.

Factory bolts won't be far off 140nm by the time you've angled them 180°

 

[Brigsy]

Seems a high torque value. Not that I know otherwise.
Saxo was 60. Which seemed on the low side, but confirmed with pug1off. Strange.

I thought it seemed like a lot but now ive sat down and thought about it, its prob not too bad.

60ft/lb not too bad, Similar to what i do the 12.9 high tensile gtt head bolts up to. Book figure is 44ft/lb on stock bolts from memory.

 

[Robbie Corbett]

Sounds like 6 uggers from a Milwaukee M12 or 4 from an M18. Make sure you cali rate your uggers.

 

[Ferdinand]

From when i rebuilt my series 2a landrover engine the best results i decided on based on research for head bolts is torque in 3-4 stages wait about 30min between each stage. Heat cycle the engine once and retorque when cold and then after about a week of being driven daily(so 7 heat cycles) retorque again.
But yeah if its abit of a b**ch to remove the valve cover that might not be practical. That was also deciced based on the type of gasket i was used, if i remeber correctly it was a steel gasket with composite layers on each side.

140nm seems entirely reasonable.

 

[Brigsy]

All went smoothly on install thanks for the advice everybody.

Ive uploaded the arp instructions on here for anybody if they are needed in the future