Aftermarket Head Bolts

[machzrobbie]

Has anyone had any problems with the aftermarket head bolts out there - specifically on APEX. Ive got one that keeps pushing coolant out the coolant bottle only under hard riding(boost) - no coolant leaks, no overheating, and will hold pressure for days.

First time I put it together I figured it was stock head bolts, so we installed new gaskets, a set of head bolts and reused the original shim. Right away it pushed coolant again, so I took it down, resurfaced head, checked for cracks, new shim and gaskets. Measured block and made sure it was straight, this time it made it 300+ trail miles and then started pushing coolant again. Someone mentioned today that there was a problem with a certian headbolt out there, just want to know if anyone else had any problems like this.

This is not my sled, I did mine the same with the ARP head studs and have had zero issues with mine running same boost.

 

[Blue shadow]

Check were the bolts go down in the block .They some time crack on the outside of the block.When the arp studs are not back off about 1/2 turn and you tork to much they crack .

 

[machzrobbie]

Check were the bolts go down in the block .They some time crack on the outside of the block.When the arp studs are not back off about 1/2 turn and you tork to much they crack .

Already checked there - its ok, thanks for the sugestion

 

[Wildman]

Do the head bolts in question have coarser threads than the others you have used? We ran into this problem last year on a sled. The head studs we purchased were from a different company. Needless to say we changed back to the finer thread Arp's and no problems since.

 

[machzrobbie]

Do the head bolts in question have coarser threads than the others you have used? We ran into this problem last year on a sled. The head studs we purchased were from a different company. Needless to say we changed back to the finer thread Arp's and no problems since.

These bolts were originally for a RX1 motor and were cut down for the Apex - I believe they are the ones that MPI was selling. They were supplied by a local performance shop to the owner of the sled. I usually get my stuff from Hurricane but he was closed down over the Christmas/Newyears holidays when the first head gasket went and these were supposed to be just as good.

 

[rxrider]

Get the ARP studs. I have them at 60Nm, no leaks.
Before you tork them down, do you add moly lube to the threads and all meeting surfaces? Very important. Tork in sequence and in steps like 20Nm 35Nm 50 Nm then 60Nm, loosen the nuts 1/4 turn and retork to 60Nm. You most likely know this already but just to be sure.... To add clamping force the bolts need to stretch a spesific percentage or else they will not clamp the head down properly. I did not cut down the studs, I added both the ARP washers and the stock washers to prevent the nuts to bottom out on the stud... if they are not cut down enough you may tork the nut to spec without adding enough clamping force and the head, it's possible.

 

[machzrobbie]

Get the ARP studs. I have them at 60Nm, no leaks.
Before you tork them down, do you add moly lube to the threads and all meeting surfaces? Very important. Tork in sequence and in steps like 20Nm 35Nm 50 Nm then 60Nm, loosen the nuts 1/4 turn and retork to 60Nm. You most likely know this already but just to be sure.... To add clamping force the bolts need to stretch a spesific percentage or else they will not clamp the head down properly. I did not cut down the studs, I added both the ARP washers and the stock washers to prevent the nuts to bottom out on the stud... if they are not cut down enough you may tork the nut to spec without adding enough clamping force and the head, it's possible.

ARP's were spun in the bolck today with locktite - and the seld will be back together tomorrow - hopefully for the last time!

 

[rxrider]

Forgot to say I used red loctite in the block and let it harden for a day, 24 hours should be enough tho. The studs should be only be torked very lightly into the block, then left for 24 hours to let the loctite harden before torking down the head.
I actually only torked the head to 20Nm the first day, the work my way up to 60Nm the next day. If the bolts slips when torking you will have to redo the procedure.... or risk the block

Hope you will not encounter more problems, downtime sucks when there is snow :-(

 

[dirk_03]

My cousin(an engine builder) said that I should use red loctite and then torque them right away to have the threads pull tight and have the loctite fill the back of the threads. Rather than letting the loctite dry with no tension on them. He felt as though this would be best. And that is what I did. of course I am not running huge boost but have not had it push any coolant out.

 

[rxrider]

Actually I ment I torked the bolts to 20Nm and let the loctite harden overnight, got the procedure from Hurricane where I bought the ARP studs. Then I torked the head down at 20Nm the next day, didn't have the time to finish her off had to finish the head tork procedure the day after

 

[machzrobbie]

The sled was out for its first test ride tonight and so far so good!! It'll be out all weekend so I should know soon. Bolts were red locktited in and set for 24 hrs and torqued to Hurrican's specs. This is the first one I've had any problems with and the only difference is the head bolts originally used. All the others were back together and out the door. I just finished a complete motor rebuild yesterday on another one with a hurricane block, JE 10:1 pistons on a stage 1 S/C @ 10# - it was out all day and only complaint was the amount of fuel being used!

 

[jabber800]

How did the supercharged apex with the 10 to 1 pistons perform at 10 lbs boost. I'm building an Apex right now using the same pistons and hoping to run 10 lbs aswell. Only thing I'm not sure about is whether I should port the heads or not? Any thoughts?

 

[zross1]

I personally let the red loctite set for a couple of days. Doing this I just pulled 50 ft/lbs on the studs with arp lube. . Needless to say my teeth were grited amoung other parts of my anatomy when doing it

 

[machzrobbie]

How did the supercharged apex with the 10 to 1 pistons perform at 10 lbs boost. I'm building an Apex right now using the same pistons and hoping to run 10 lbs aswell. Only thing I'm not sure about is whether I should port the heads or not? Any thoughts?

The porting will make more HP if done properly - the problem we're having right now is with the GEMS - it has a real rich stumble at around 6000 RPM where it goes from vacum to boost. I had the same problem on mine, but I'm using a boondocker and actually had to take fuel out of this spot. With the GEMS you cannot pull fuel. I talked to Matt at MPI and he says its a problem with the S/C and GEMSwhen decompressed.

 

[rxrider]

For that reason I low the RB3 and MCX controllers. They have mapping capabilities for TPS vs Boost and Boost vs Fuel. You will be able to tune around problem areas easily.