There's no need to locktite the 12 bolts surrounding the edge of the plenum because they stay torqued. If you're going to use locktite, use the lower adhesive verison. There's no need to go with something really strong. Tommorrow I'll check and see how much the center bolts have loosen over the course of 2.5 days. I'll probably retorque the bolts to 90 in/lbs and see how that holds.

 

Okay, so last night I rechecked the bolts after two days and numerous heat cycles. The last time I torqued the bolts, I kicked up the torque to 70 in/lbs. When I checked the bolts last night, 3 were still torqued to 70 in/lbs and 3 were about 1/10 of turn loosen or at around 60 in/lbs. It looks like 70-75 in/lbs may be the ideal torque range.

 

Hi Dave,

I would have responded earlier but didn't surf across this thread untill now.

During the material selection process I intentionally wanted a material that would not be hard. The material is strong but it also has a moderate amount of elastic compliance. The softness will allow conformity for good hermetic sealing.

As you have noticed, the supports will essentially yeild enough to conform to the torque level as applied by the bolts. Thermal cycling is almost like an annealing process to allow the plastic to set. So when you torque it down cold, it is under stress. After a thermal cycle, the stress relieved but the spacer is still strong and will support the plenum from vacume/pressure cycles. The material KSI and support area makes it good for 1800 lbs force.

As a result, you don't need to retorque the bolts. The main criteria is maintaining a good seal and that is accomplished within the first torq application.

 

So even if the bolts loosen to say 30in/lbs, you shouldn't retorque them down? What about the loctite idea, any concern you would have regarding that?

 

The bolts never actually "loosen" or move. So you don't need to retorque them. Loctite is optional.

 

So what amount of torque do you recommend? 60 in/lbs doesn't seem to do the job when torquing down the center bolts on a cold manifold. Is the 60 in/lbs recommendation incorrect and should have been 100 in/lbs? 70-75 in/lbs seems to be doing the job. By the way, the spacer is sweet. Perfect fit, easy install, no compromises, and good power.

 

50 to 75 is fine for the 6 center bolts. It really only needs to be enough to hold everything sealed and in place. The bolts on the outer perimiter are what can use the 100 in torq spec.

 

Like I said in my thread reviewing the mrev, I don't have a torque wrench, so I just hand-tightened the upper plenum with a nut driver. I checked over the weekend, and none had moved(that I could tell). I checked again this evening, with the same results.

 

Update

After 10 days of use, I rechecked the torque on the 6 center bolts and they were still holding 75 in/lbs. For my car, that appears to be the necessary torque required to the hold the bolts.

 

I checked my bolts, last night. After torquing the 6 center bolts twicw after the first initial time . . . All 6 bolts are holding at 60 inch-lbs. The last time I torqued them was some 2 weeks ago.

 

where can you purchase loctite?

 

At any autostore.

I wouldn't bother with it though. I think Hydrazine is right in that the plastic spacers heat cycle and after a while they stop cycling which allows you to get the bolts perfectly torqued. Mine are still at 75 in/lbs and holding fine.

 

Tonys instructions are your bible on install of his
spacer. Installed mine with the motor totally cold
and used a highend torq wrench. Damn thing beeps
when you've reached the correct setting. No problems with MotorDyne here!!