23 replies to this topic

[Kerrin]

Right, thanks for the replies.

Head re-torqued to 50ft/lb and each nut gave about another 1/2 turn to torque.

Also re-set tappets as they were all slightly tight with the head tightening down on the pushrods.

Cheers

[blacktulip]

if its a 998 you shouldnt go much over 40ft/lbs as you run the risk of damaging the fire ring. 60ft/lbs seems excessive IMO

[Kerrin]

Ok

Just checked all 3 of my haynes manuals and the newer two say 50ft/lb and the oldest one says 42ft/lb

The torque list in the FAQ says 42ft/lb.

mine are done to 50.

My motor is a 1380 with about 10.5:1 compression

Edited by Kerrin, 10 March 2009 - 11:12 PM.

[blacktulip]

you should be ok with that

[bigmotherwhale]

i just wanted to point out to prawn, that the guy probably meant newton meters not foot pounds as 60nm is 44 foot pounds which is about right, if you did torque to 60 foot pounds id bet you have completely screwed the block and cylinder head in the process they would need to be skimmed and possibly the block rebored as it would distort. that is if the studs didnt strip the threads from the block.

[mini7boy]

i just wanted to point out to prawn, that the guy probably meant newton meters not foot pounds as 60nm is 44 foot pounds which is about right, if you did torque to 60 foot pounds id bet you have completely screwed the block and cylinder head in the process they would need to be skimmed and possibly the block rebored as it would distort. that is if the studs didnt strip the threads from the block.

maybe unnecessary to say so now, but:

1) the amount of torque to use depends on the type of lube, if any, used. The differences are great: 60 lbs/ft with motor oil, 40 lbs/ft with ARP moly lube.

2) re-torquing only requires trying to tighten the nuts further without loosening them

3) given the large number of forum items pertaining to head gasket failures, it should be obvious that serious care is needed when preparing the block/head surfaces, using quality gaskets and torquing them properly with some form of lube.

4) lots of people get away without re-torquing, but re-torquing shows you care and is likely to increase the chances for success.

[bigmotherwhale]

you NEVER torque a head gasket to 60 lbs/ft even with engine oil on the threads the highest it should ever be is 50lbs/ft,
you really think engine oil is that bad as a lubricant?! thats 20lbs/ft difference! you will break your fire ring lol

just because you can torque to 65lbs.ft doesnt mean you should, i take it that we are talking about arp head stud kit here? not the standard ones?

Edited by bigmotherwhale, 11 March 2009 - 01:18 PM.

[Prawn]

look, guys, I don't want to start any arguements, the instructions, written by ARP, that came in the box with my studs, said to use 60lbft with engine oil, and the guy at the rolling road said the same.

I'm not confusing LBft and Nm, I did exactly as I was told. It's running fine, so I don't see the problem. I'm not going to do it again, but I did exactly as the ARP instructions said so, so if my block/head are damamged, I shall be writing a nice letter to ARP asking them to fix it

[mini7boy]

look, guys, I don't want to start any arguements, the instructions, written by ARP, that came in the box with my studs, said to use 60lbft with engine oil, and the guy at the rolling road said the same.

I'm not confusing LBft and Nm, I did exactly as I was told. It's running fine, so I don't see the problem. I'm not going to do it again, but I did exactly as the ARP instructions said so, so if my block/head are damamged, I shall be writing a nice letter to ARP asking them to fix it

in case you haven't already, look at the ARP website and look at the technical materials they have prepared to guide people in using their fasteners. They are obviously at the top of engine fastener technology and you are using their product. So why would you take the advice of a bunch of hobbyist engine builders?

I got it wrong initially because I didn't read your note carefully enough to see you were using motor oil as a lube. I have only ever installed ARP bits, both head nuts and rod bolts, using the ARP moly lube. So, I foolishly assumed that everyone does. WRONG !!! Then I corrected my self by quoting the ARP factory literature that said only 40 lbs/ft for use with ARP lube and 60 lbs/ft with motor oil.

I'll admit that's a big difference, but the folks at ARP know their stuff and have no reason to lie.

For future use, I would recommend that anyone using ARP fasteners use the ARP lube. You paid a lot of money for the fasteners, so why would you want to cheap out on the lube?

In the U.S., ARP lube costs less than 3 quid for more than enough to build one Mini engine. For about 5 quid, you will have enough for at least 2-3 engines. At prices like this, why screw around?