Torque head bolts past spec for big boost ?

[princesledalot]

I noticed if iI ran 17 + lbs boost I was loosing coolant so I'm wondering if I should retorque my head bolts tighter than the Yamaha specs. I have the Powderlites headshim with a half gasket on each side.

 

[Boyko]

Twisting up your bolts more will strech them and then thay get week and then you should replace them. You might want to try molly lube and factory specs????
The best idea is some good bolts, problem solved, peace of mind and just wait for snow.

 

[princesledalot]

Thanx for the reply, I did use the moly when I put it together. I should have used the Ti bolts I guess.

 

[Boyko]

Twisting up your bolts more will strech them and then thay get week and then you should replace them. You might want to try molly lube and factory specs????
The best idea is some good bolts, problem solved, peace of mind and just wait for snow.

 

[snowy1]

get some heavy duty cromemoly studs, and then you can tork them tighter with out stretching the studs,

 

[Anonymous]

ARP

I torqued them to 45 ft-lbs....

 

[Turbo Tim]

I noticed if iI ran 17 + lbs boost I was loosing coolant so I'm wondering if I should retorque my head bolts tighter than the Yamaha specs. I have the Powderlites headshim with a half gasket on each side.

I tightened mine slightly past Mcx specs , (maybe 4 ft pds.past) ....I split the factory head gasket , cleaned all the factory sealer off to where they were bare metal.Then I sprayed both sides of each half of the gasket with copper spray (several coats).Also sprayed the shim on both sides.Placed the shim between both halves. No probs. Running at 17 psi.

 

[powderlites]

Head bolts

We have guys running 23 PSI boost on Apex with stock bolts and head spacer?
On first torque is 14 try 17/18 instead with lube.

 

[TWIN TURBO]

Don't use moly and don't over torque stock studs your just going to stretch them like someone previosly said. Install oversize studs like ARP and torque them to their specs.

 

[Anonymous]

Don't use moly and don't over torque stock studs your just going to stretch them like someone previosly said. Install oversize studs like ARP and torque them to their specs.

My arp studs were not any bigger than stocker, just not the same alloy!

 

[TWIN TURBO]

There are larger diameter studs avialible but even the studs you have are probably better, alloys do make a difference.

 

[snowy1]

the arp studs should be larger than stock, I have installed 2 sets and they were both larger than stock, tell them you want heavy duty studs for 1999-2001 r1 motor they are the same as the rx1.

 

[Anonymous]

Only thing I had to do was to cut them a little because they were too long (R1)..

By bigger, I assumed you meant you had to oversize the hole... and I did not resized any of the holes!

 

[snowy1]

no I did not have to over size the stud holes, the center recessed area between the threads on the stock studs is not recessed on the arp,s they are the same diameter all the way top to bottom. and you should not have to shorten the studs. if you had to shorten them they may be the wrong studs.

 

[4strokes are better than2]

where are you getting the arp studs from